Yamaha DT 125 X Re 2005 Manual de Reparatie Www.manualedereparatie.info

SERVICE MANUAL

DT125RE 1D01-AE1

DT125X2005

DT125RE/X1D01-1D02/2C81

SERVICE MANUAL© 2005 Yamaha Motor España, S.A.

1st Edition, January 2005All rights reserved. Any reprinting orunauthorized use without the written

permission of Yamaha Motor España, S.A. is expressly prohibited.

Printed in Spain.

EAS00001

EAS00002

NOTICEThis manual was produced by the Yamaha Motor España S.A. primarily for use by Yamaha dealersand their qualified mechanics. It is not possible to include all the knowledge of a mechanic in onemanual. Therefore, anyone who uses this book to perform maintenance and repairs on Yamahavehicles should have a basic understanding of mechanics and the techniques to repair these typesof vehicles. Repair and maintenance work attempted by anyone without this knowledge is likely torender the vehicle unsafe and unfit for use.Yamaha Motor España S.A is continually striving to improve all of its models. Modifications and sig-nificant changes in specifications or procedures will be forwarded to all authorized Yamaha dealersand will appear in future editions of this manual where applicable.

NOTE:

Designs and specifications are subject to change without notice.

TECHNICAL PUBLICATIONSYAMAHA MOTOR ESPAÑA, S.A.

EAS00004

IMPORTANT MANUAL INFORMATIONParticularly important information is distinguished in this manual by the following.

The Safety Alert Symbol means ATTENTION! BECOME ALERT!YOUR SAFETY IS INVOLVED!

Failure to follow WARNING instructions could result in severe injuryor death to the motorcycle operator, a bystander or a person chec-king or repairing the motorcycle.

A CAUTION indicates special precautions that must be taken toavoid damage to the motorcycle.

A NOTE provides key information to make procedures easier or cle-arer.

tt

ss WARNING

CAUTION

NOTE :

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HOW TO USE THIS MANUALThis manual is intended as a handy, easy-to-read reference book for the mechanic. Comprehensiveexplanations of all installation, removal, disassembly, assembly, repair and check procedures arelaid out with the individual steps in sequential order.

The manual is divided into chapters. An abbreviation and symbol in the upper right cor-ner of each page indicate the current chapter.Refer to “SYMBOLS”.

Each chapter is divided into sections. The current section title is shown at the top of eachpage, except in Chapter 3 (“PERIODIC CHECKS AND ADJUSTMENTS”), where the sub-section title(s) appears.

Sub-section titles appear in smaller print than the section title.

To help identify parts and clarify procedure steps, there are exploded diagrams at the startof each removal and disassembly section.

Numbers are given in the order of the jobs in the exploded diagram. A circled number indi-cates a disassembly step.

Symbols indicate parts to be lubricated or replaced.Refer to “SYMBOLS”.

A job instruction chart accompanies the exploded diagram, providing the order of jobs,names of parts, notes in jobs, etc.

Jobs requiring more information (such as special tools and technical data) are describedsequentially.

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SYMBOLSThe following symbols are not relevant toevery vehicle.

Symbols to indicate the subject of eachchapter.

General information Specifications Periodic checks and adjustments Chassis Engine Cooling system Carburetor(s) Electrical system Troubleshooting

Symbols 10 to 17 indicate the following.

10 Serviceable with engine mounted11 Filling fluid12 Lubricant13 Special tool14 Tightening torque15 Wear limit, clearance16 Engine speed17 Electrical data

Symbols 18 to 23 in the exploded diagramsindicate the types of lubricants and lubrica-tion points.

18 Engine oil19 Gear oil20 Molybdenum-disulfide oil21 Wheel-bearing grease22 Lithium-soap- based grease23 Molybdenum-disulfide grease

Symbols 24 to 25 in the exploded diagramsindicate the following.

24 Apply locking agent (LOCTITE®)25 Replace the part

CHKADJ

ENG

CARB

TRBLSHTG

SPEC

CHAS

COOL

ELEC

GENINFO

New

11

13

16

18

21

24

10

12

15 17

25

20

23

19

22

14

SPEC 2SPECIFICATIONS

CHKADJ 3

PERIODIC CHECKS ANDADJUSTMENTS

CHAS 4CHASSIS

ENG 5ENGINE

COOL 6COOLING SYSTEM

CARB 7CARBURETOR

ELEC 8ELECTRICAL SYSTEM

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TABLE OF CONTENTS

TRBLSHTG 9TROUBLESHOOTING

GENERAL INFORMATION GENINFO 1

GENINFO

1

GENINFO

CHAPTER 1GENERAL INFORMATION

MOTORCYCLE IDENTIFICATION ……………………………………………1-1FRAME SERIAL NUMBER ……………………………………………………1-1ENGINE SERIAL NUMBER……………………………………………………1-1

IMPORTANT INFORMATION …………………………………………………1-2PREPARATION FOR REMOVAL ……………………………………………1-2ALL REPLACEMENT PARTS …………………………………………………1-2GASKETS, OIL SEALS AND O-RINGS ……………………………………1-2LOCK WASHERS/PLATES AND COTTER PINS……………………………1-2BEARINGS AND OIL SEALS …………………………………………………1-3CIRCLIP …………………………………………………………………………1-3CHECKING THE CONNECTIONS……………………………………………1-4

SPECIAL TOOLS …………………………………………………………………1-5

GENINFOMOTORCYCLE IDENTIFICATIONS

1-1

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GENERAL INFORMATIONMOTORCYCLE IDENTIFICATIONFRAME SERIAL NUMBERThe frame IDENTIFICATION number isstamped onto the steering head pipe.NOTE:The frame serial number is used to identify themotorcycle and therefore it can be used for theenrollment in the face of the competent autho-rity.

ENGINE SERIAL NUMBERThe engine serial number is stamped ontothe left side of the crankcase.NOTE:The first three digits of this number identifies“the model; the other digits indicate the num-ber” of production of the unit.

NOTE:Design and specifications may change withoutnotice.

GENINFOIMPORTANT INFORMATION

1-2

IMPORTANT INFORMATIONPREPARATION FOR REMOVAL AND DISASSEMBLY1. Before removal and disassembly, remove all

dirt, mud, dust and foreign material.2. Use only the proper tools and cleaning

equipment.Refer to the “SPECIAL TOOLS”.

3. When disassembling, always keep matedparts together. This includes gears, cylin-ders, pistons and other parts that havebeen “mated” through normal wear. Matedparts must always be reused or replaced asan assembly.

4. During disassembly, clean all of the partsand place them in trays in the order ofdisassembly. This will speed up assemblyand allow for the correct installation of allparts.

5. Keep all parts away from any source of fire.

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REPLACEMENT PARTSUse only genuine Yamaha parts for all replace-ments. Use oil and grease recommended byYamaha for all lubrication jobs. Other brandsmay be similar in function and appearance, butinferior in quality.

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GASKETS, OIL SEALS AND O-RINGS1. When overhauling the engine, replace all

gaskets, seals and O-rings. All gasket sur-faces, oil seal lips and O-rings must be cle-aned.

2. During reassembly, properly oil all matingparts and bearings and lubricate the oil seallips with grease.

GENINFOIMPORTANT INFORMATION

1-3

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BEARINGS AND OIL SEALSInstall bearings and oil seals so that the manu-facturer’s marks or numbers are visible. Wheninstalling oil seals, lubricate the oil seal lipswith a light coat of lithium-soap-based grease.Oil bearings liberally when installing, if appro-priate. Oil seal

CAUTION

Do not spin the bearing with compressedair because this will damage the bearingsurfaces.

Bearing

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CIRCLIPSBefore reassembly, check all circlips carefullyand replace damaged or distorted circlips.Always replace piston pin clips after one use.When installing a circlip , make sure thesharp-edged corner is positioned oppositethe thrust that the circlip receives. Shaft

GENINFOCHECKING THE CONNECTIONS

1-4

EAS00026

CHECKING THE CONNECTIONSCheck the leads, couplers, and connectors forstains, rust, moisture, etc.1. Disconnect:• lead• coupler• connector

2. Check:• lead• coupler• connector

Moisture Dry with an air blower.Rust/stains Connect and disconnectseveral times.

3. Check:• all connections

Loose connection Connect properly.

NOTE:

If the pin on the terminal is flattened, bendit up.

4. Connect:• lead• coupler• connector

NOTE:

Make sure all connections are tight.

5. Check:• continuity

(with the pocket tester)

NOTE:

• If there is no continuity, clean the terminals.• When checking the wire harness, perform

steps (1) to (3).• As a quick remedy, use a contact revitalizer

available at most part stores.

Pocket tester90890-03112, YU-3112

GENINFOSPECIAL TOOLS

1-5

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SPECIAL TOOLSThe following special tools are necessary for complete and accurate tune-up and assembly. Useonly the appropriate special tools as this will help prevent damage caused by the use of inappro-priate tools or improvised techniques. Special tools, part numbers or both may differ depending onthe country.When placing an order, refer to the list provided below to avoid any mistakes.

Tool No. Tool name / Usage Illustration

90890-01312 Fuel level gauge

This gauge is used to measure the fuel level in the float chamber.

90890-03113 Engine tachometer

This tool is needed for detecting engine rpm.

90890-04086 Universal tool of subjection of the clutch

This tool is used to immobilize the clutch during the assembly or disassembly of theblockade nut of the clutch.

90890-01701 Sheave holder

This tool is used for holding the secondary sheave.

90890-01362 Flywheel puller

For removing the flywheel.

90890-01304 Piston pin puller

This tool is used to remove the piston pin.

90890-01325 Radiator cap tester90890-01352 Adaptor

These tools are used for checking the cooling system.

GENINFOSPECIAL TOOLS

1-6

Tool No. Tool name / Usage Illustration

90890-01135 Crankcase separation tool

This tool is used to remove the crankshaft or separate the crankcase.

90890-01274 (1) Cranckshaft intalling tool-01275 (2) Crankshaft pin -01278 (3) Adapter(M12)

90890-01326 T-Handle

This tool is used for holding the damperrod holder when removing or installing the damper rod holder.

90890-01367 Fork seal driver weight-01381 Fork seal driver attachment

This tool is used when installing the fork seal.

90890-01403 Ring nut wrench

This tool is used to loosen and tighten the steering ring nut.

90890-03112 Pocket tester

These instruments are invaluable for checking the electrical system.

SPEC

2

SPEC

CHAPTER 2SPECIFICATIONS

GENERAL SPECIFICATIONS …………………………………………………2-1ENGINE SPECIFICATIONS……………………………………………………2-4CHASSIS SPECIFICATIONS …………………………………………………2-6ELECTRICAL SPECIFICATIONS ……………………………………………2-8

CONVERSION TABLE …………………………………………………………2-10

GENERAL TIGHTENING TORQUE SPECIFICATIONS ……………………2-10ENGINE ………………………………………………………………………2-11CHASSIS ……………………………………………………………………2-11

COOLANT FLOW CHART ……………………………………………………2-13

LUBRICATION POINTS AND LUBRICANT TYPE …………………………2-14ENGINE ………………………………………………………………………2-14CHASSIS ………………………………………………………………………2-15

CABLE ROUTING ………………………………………………………………2-16

SPECGENERAL SPECIFICATIONS

2-1

SPECIFICATIONSGENERAL SPECIFICATIONS

Model DT125RE DT125X

Model code 1D01/1D02 2C81

Dimensions:Overall lenght 2210mm 2139mmOverall width 795mm 1121mmOverall height 1200mm 1200mmSeatheight 900mm 886mmWheelbase 1415mm 1396mmMinimum ground clearance 300mm 271 mmMinimum turning radius 2100mm 2016mm

Basic weight:With oil and full fuel tank 126kg 134 kg

Engine:Engine type: 2 strokes, liquid cooledInduction system Reed valveCylinder arrangement Forward-inclined single cylinderDisplacement 124cm3

BorexStroke 56,0x50,7Compression ratio 6,7:1Maximum power 11kW /8000rpmMaximum torque 13Nm/8000rpmIdle speed 1250~1450r/minStarting system Electric starterLubrication system Yamaha Autolube

Oil type or grade:Engine oil 2T motor oil (JASO grade FC)Total amount 1,3LTransmission oil Type SE motor oilPeriodic oil change 0,75L (0,79 us. qt.)Total amount 0,8L (0,85 us.qt.)

Radiator capacity:Total amount (including all routes) 0,92LCoolant reservoir capacity 0,30L

Air filter: Wet type element

FuelType Regular unleaded gasoline

Fuel tank capacity: 10,7LReserve 1,8L

Carburetor:Type/quantity TM28-92 / 1

Manufacturer: MIKUNI


2-2

Model code 1D01/1D02 2C81Spark plug:

Type BR8ESManufacturer NGKSpark plug gap 0,7~0,8mm (0,0276~0,03315in)

Clutch type Wet, multiple discTransmission:

Primary reduction system Helical gearPrimary reduction ratio 71/22(3,227)Secondary reduction system chain driveSecondary reduction ratio 57/16(3,563)Transmission type Constant mesh, 6 speedOperation Left foot operation

Gear ratio:1ª 34/12(2.833)2ª 30/16(1.875)3ª 24/17(1.412)4ª 24/21(1.143)5ª 22/23(0.957)6ª 18/22(0.818)

Chassis:Frame type: Semi double cradle Semi double cradleCastor angle 27º 24,5°Trail 107mm 73,1 mm

Tire:Type With tube With tubeSize

Front 80/90-21 48P 120/70-17 58HRear 110/80-18 58P 140/70-17 66H

Manufacturer Michelin /T63 Pirelli/ Sport DemonCold tire pressure:

Front 0~90kg 150kPa (1.5kgf/cm2) 180kPa (1.8kgf/cm2)Rear 0~90kg 175kPa (1.75kgf/cm2) 200kPa (2.0kgf/cm2)Front 90~178kg 175kPa (1.75kgf/cm2) 180kPa (1.8kgf/cm2)Rear 90~178kg 200kPa (2.0kgf/cm2) 200kPa (2.0kgf/cm2)

Off road riding:Front 150kPa (1.5kgf/cm2)Rear 175kPa(1.75kgf/cm2)

Brakes:Front brake type Single disc brake Single disc brake

230mm diameter 298 mm diameterFront brake operation Right hand operation Right hand operationRear brake type Single disc brake Single disc brake

220mm diameter 220 mm diameterRear brake operation Right foot operation Right foot operation

Suspensions:Front Telescopic forkRear Swingarm (monocross suspension)

Shock absorber:Front Coil-air spring/Oil damperRear Coil and gas spring/Oil damper


2-3

Model code 1D01/1D02 2C81

Wheel travel:Front wheel travel 270mm(10.63in) 200mm (7,87in)Rear wheel travel 260mm(10.24in) 230mm (9.05in)

Electrical:Ignition system CDICharging system AC MagnetoBattery type GT6B-3Capacity 12V 6Ah

Headlight: bulb type

Bulb wattage x quantity:Headlight 12V60W/55W x 1Tail/Brake light 12V21W/5W x 1Turn signal indicator light

Front 12V10W x 1Rear 12V10W x 1

Meter LED

Control lights:“OIL” 12V3W X 1“TURN” 12V3W X 1“NEUTRAL” 12V3W X 1“HIGH BEAM” 12V3W X 1“LOW BEAM” 12V3W X 1

Amperages:Principal fuse 15A


2-4

Item Standard Limit

Cylinder head:Warpage limit * Lines indicate 0,03mm

straightedge measurement.

Cylinder:Bore size 56.00~56.02mm ***Taper limit 0.05mm ***Out of round limit 0.01mm ***

Piston:Piston size “D” 55.950~55.955 ***Measurement point* 10mm ***Piston to cylinder

clearance 0.045~0.050mm 0.10mmPiston Offset 0.5mm ***

Piston ring:Type Keystone ***Dimensions(BxT): * *Top ring 1.2x2.4mm ***2nd ring 1.20x1.89mm ***End gap (installed): * *Top ring 0.30~0.45mm ***2nd ring 0.30~0.45mm ***Side clearance: * *Top ring 0.02~0.06mm ***2nd ring 0.035~0.070mm ***

Cooling system:Radiator capacity (including all routes) 0.92L ***Reservoir tank capacity 0.3L *Radiator cap opening pressure 75~105kPa ***

(0.75~1.05kgf/cm2)Radiator core width 110mm ***Radiator core height 280mm ***Radiator core thickness 32mm ***Water pump type Single-suction centrifugal

pump

ENGINE


2-5

Item Standard Limit

Crankshaft:

Crank width “A” 57.90~57.95mm ***Runout limit “C” *** 0.03mmBig end side clearance “D” 0.2~0.7mm ***Small end free play “E” 0.026~0.040mm ***

Clutch:Friction plate thickness 2.9~3.1mm 2.7mmQuantity 7pcs ***Clutch plate thickness 1.05~1.35mm 0.05mmQuantity 6pcs ***Clutch spring Free lenght 34.5mm ***Quantity 5pcs ***Minimum free lenght 32mm ***Push rod bending limit 0.15mm ***

Transmission:Main axle runout limit *** 0.08mmDrive axle runout limit *** 0.08mm

Carburetor:Type TM28-92/1 ***ID Mark 1DO ***Main jet #210 ***Air jet 0.7 ***Jet Needle position 5J40-2 ***Needle jet Q2M (#939) ***Pilot outlet 0.6 ***Pilot jet #17.5 ***Bypass1 1.6 ***Air screw turns 1/4 ***Valve seat size 2.8 ***Starter jet 1 #40 ***Power jet #60 ***Float height 15.5~16.5mm ***Fuel level 1.5~2.5mmIdling speed 1250~1450r.p.m

Air filter:Type Wet element ***Oil type/grade Foam air filter oil or ***

SAE10W30SEReed valve:Valve thickness 0.5mm ***Valve stopper height 8.8mm *** Valve bending limit 0.5mm ***

Lubrication system:Autolube pump * *Color code Dark blue ***Minimum stroke 0.15~0.20mm ***Maximum stroke 1.85~2.05mm ***Minimum output 0.38~0.50cm3 ***Maximum output 4.65~5.15cm3 ***Pulley adjusting mark autoadjustable ***


2-6

CHASSIS

Item Standard Limit

Model code 1D0 2C81 1D0 2C81Front wheel:

Type Spoke wheels Spoke wheelsRim Size 21x1.60 17 x 3.00Rim Material Steel SteelFront wheel travel: 270mm 270mmMax. Radial wheel runout 1mm 1mmMax. Lateral wheel runout 0.5mm 0.5mm

Rear wheel:Type Spoke wheels Spoke wheelsRim size 18x1.85 17x3.50Rim material Steel SteelRear wheel travel 260mm(10.24in) 260mm(10.24in)Max. Radial wheel runout 1mm(0.04in) 1mm(0.04in)Max. Lateral wheel runout 0.5mm(0.02in) 0.5mm(0.02in)

Front disc brake:Thickness 230.0x3.5mm 230.0x3.5mmBrake pad lining thickness-inner 6mm 4.1mm 0.8mm 0.5mmBrake pad lining thickness-outer 6 mm 6 mm 0.8mm 0.8mmMaster cylinder inside diameter 11mm 11mmCaliper cylinder inside diameter 34.93mm 34.93mmRecommended fluid DOT 4 DOT 4

Rear disc brake:Thickness 220.0x4.5mmBrake pad lining thickness-inner 5.6mm 1.0mmBrake pad lining thickness-outer 5.6mm 1.0mmMaster cylinder inside diameter 12.7mmCaliper cylinder inside diameter 30.16mmRecommended fluid DOT 4

Steering system:Steering type Ball and taper roller

bearingBearing size (quantity)Upper 22pcs (0.1875in)

Front suspension:Front fork travel 270mm 200 mmFork free lenght 503mm 503mmSpring rate K1 3.1N/mm 3.1N/mmSpring stroke K1 0~270mm 0~270mmOptional spring available No NoRecommended oil Fork oil 10W Fork oil 10WQuantity 495cm3 495cm3

Level 165.5mm 165.5mm


2-7

Item Standard Limit

Model code 1D0 2C81 1D0 2C81Rear suspension:

Type Swingarm Swingarm(link suspension) (link suspension)

Rear shock absorber assemby travel 93mm 87 mmSpring free lenght 245mm 250mmInstalled lenght 230mm 244mmSpring preload (spring lenght) Hard/Soft Hard/Soft

(220/235mm) (234/249mm)Spring rate K1 68.6N/mm 117.80N/mmSpring stroke K1 0~93mm 0~87mmOptional spring available No NoEnclosed gas/air pressure (STD) 150kPa 150kPa

(15kgf/cm2) (15kgf/cm2)Tightening torque spring preload 20~25Nm 20~25Nm

Drive chain:Type/Manufacturer 428V2/DAIDO 428V2/DAIDOLink quantity 134 134Drive chain slack 45~55mm 25~40mm

(1.77~2.16in) (0.98~1.57in)

Front lever brake/Rear brake pedal:Free play front lever brake 2~5mmBrake pedal free play 15mm

GENINFOGENERAL SPECIFICATIONS

2-8

ELECTRICAL

Model 1D01/1D02 2C81System voltage 12 V

Ignition system:Ignition system type C.D.I.Ignition timing (B.T.D.C.) ((º)) 17 /1500r/minAdvancer type Digital

C.D.I.:Magneto model/manufacturer F4FU/YAMAHAPick up coil resistance((ohm)) 310±20%W/R-W/LSource coil resistance ((ohm)) 730±20%B/R-G/WSource coil resistance ((ohm)) 600±20%G/L-G/WCDI unit model/manufacturer 1D0 /YAMAHA

Ignition coil:Model/Manufacturer 3RW/YAMAHAPrimary coil resistance ((ohm)) 0.23±20%Secondary coil resistance ((ohm)) 7.9±20%

Spark plug cap:Material ResinResistance ((k ohm)) 5

A.C. Magneto:Model/Manufacturer F4FU/YAMAHAStandard output 14V170W5000r/minCoil resistance ((ohm)) 0.6±20%W-W

Regulator:Regulator type Semi conductor-short circuitModel/Manufacturer SH629B-11/SHINDENGENNo load regulated voltage 14.1~14.9V

Rectifier:Rectifier capacity 25AWithstand voltage 200V

Battery:Battery type GT6B-3Battery voltage/Capacity 12V6Ah

Bulbs (voltage/wattage x quantity)Headlight type Bulb typeHeadlight bulb type Halogen H4Headlight 12V60W/55Wx1Auxiliary light 12V5Wx1Brake/tail light 12V21W/5Wx1Front flasher light 12V10Wx2Rear flasher light 12V10Wx2Meter light LED

GENINFOGENERAL SPECIFICATIONS

2-9

Indicator lightNeutral indicator light 12V3Wx1Turn indicator light 12V3Wx1Oil level indicator light 12V3Wx1High beam indicator light 12V3Wx1

Starting system:System type Electric starter

Starter motor:Model/Manufacturer 3MB / MoricPower output 0.2kWArmature coil resistance 0.0315~0.0385<ohm> 20ºCBrush overal lenght 5X7X7<Limit> 3,5Brush spring force 4.9N ±20%<Limit> 3.92NCommutator diameter 17.6mm<Limit> 16.6mmMica undercut (depth) 1.35mm

Starter relay:Model/Manufacturer 1D0/JIDECOAmperage 180ACoil resistance 4.2 - 4.6<ohm> 20ºC

Horn:Horn type PlaneQuantity 1Model/Manufacturer YF-12/NIKKOMax. Amperage 3APerformance 105~113db/2m

Turn signal relay:Relay type Full transistorModel/Manufacturer FE218BH/DENSOTurn signal blinking frequency 75~95cyl/minWattage 10Wx2+3.4W

Oil level gauge:Model/Manufacturer 3XP/ASTI

Starting citcuit cutt-off relay:Model/Manufacturer 25G/OMRONCoil resistance 100<ohm>±10%

Headlight relay:Model/Manufacturer 25G/OMRONCoil resistance 100<ohm>±10%

Side stand relay: BUILT IN CUT OFF RELAY

Thermostat switch:Model/Manufacturer 4BA/DENSOTemperature setting 120±3<degree>

Servo motor:Model/Manufacturer 3XP/MATSUSHITA

Amperage for fuses:Main fuse 15ASpare fuse 15A

SPECCONVERSION TABLE /

GENERAL TIGHTENING TORQUES SPECIFICATIONS

2-10

EAS00028

CONVERSION TABLEAll specification data in this manual are listedin SI and METRIC UNITS.Use this table to convert METRIC unit data toIMPERIAL unit data.

Ex.METRIC MULTIPLIER IMPERIAL** mm x 0.03937 = ** in2 mm x 0.03937 = 0.08 in

CONVERSION TABLE

METRIC TO IMPERIALMetric unit Multiplier Imperial unit

m•kg 7.233 ft•lbTightening m•kg 86.794 in•lb

Torque cm•kg 0.0723 ft•lbcm•kg 0.8679 in•lb

Weight kg 2.205 lbg 0.03527 oz

Speed km/hr 0.6214 mph

km 0.6214 mim 3.281 ft

Distance m 1.094 ydcm 0.3937 inmm 0.03937 in

cc (cm3) 0.03527 oz (IMP liq.)Volume, cc (cm3) 0.06102 cu•inCapacity lt (liter) 0.8799 qt (IMP liq.)

lt (liter) 0.2199 gal (IMP liq.)

kg/mm 55.997 lb/inMisc. kg/cm2 14.2234 psi (lb/in2)

Centigrade 9/5 + 32 Fahrenheit (°F)(°C)

EAS00029

GENERAL TIGHTENING TORQUESPECIFICATIONSThis chart specifies tightening torques forstandard fasteners with a standard ISO threadpitch. Tightening torque specifications forspecial components or assemblies are provi-ded for each chapter of this manual. To avoidwarpage, tighten multi-fastener assemblies ina crisscross pattern and progressive stagesuntil the specified tightening torque is rea-ched. Unless otherwise specified, tighteningtorque specifications require clean, dry thre-ads. Components should be at room tempera-ture.

A: Width across flatsB: Thread diameter

A BGeneral tightening

(nut) (bolt)torques

Nm m • kg10 mm 6 mm 6 0.612 mm 8 mm 15 1.514 mm 10 mm 30 3.017 mm 12 mm 55 5.519 mm 14 mm 85 8.522 mm 16 mm 130 13.0

SPECDEFINITION OF UNITS

2-11

TIGHTENING TORQUESENGINE

TighteningThread torque

Part to be tightened Q’ty size Nm m•kg Remarks

Spark plug 1 M14x1.25 20 2,0

Cylinder head Nut 5 M8x1.25 22 2,2

Cylinder Stud bolt 9 M8X1.25 13 1,3 LOCTITE screw glue

Nut 4 M8x1.25 28 2,8

Power valve holder, Valve cover Cap seal

Bolt 6 M5x0.8 7 0,7

Power valve pully Bolt M6x1.0 10 1,0

Thermostat valve cover Screw 3 M6x1.0 8 0,8

Housing cover Screw 2 M6x1.0 8 0,8

Drain bolt (Housing cover) 1 M6x1.0 10 1

Radiator Bolt 2 M6x1.0 8 0,8

Radiator cap stopper Screw 1 M5x0.8 5 0,5

Oil pump Screw 2 M5x0.8 5 0,5

Carburetor joint Bolt 4 M6x1.0 8 0,8

Air filter Screw 2 M6x1.0 5 0,5

Exhaust pipe Nut 2 M8x1.25 18 1,8Stud bolt 2 M8x1.25 10 1 LOCTITE

screw glue

Bolt 3 M6x1.0 8 0,8

Transmission Oil Drain Bolt 1 M8x1.25 15 1,5

Crankcase cover (left) Screw 6 M6x1.0 5 0,5

Crankcase cover (right) Screw 6 M6x1.0 8 0,8

Oil pump cover Screw 3 M6x1.0 5 0,5

Crankcase Screw 12 M6x1.0 8 0,8

Oil Seal Holder Screw 1 M8x1.25 16 1,6

Cover Screw 2 M6x1.0 8 0,8

Kick Crank Bass Nut 1 M12X1.0 70 7

Clutch Spring Bolt 5 M5x0.8 6 0,6

Plate cover Screw 2 M6x1.0 10 1

Drive Sprocket Nut 1 M16X1.0 60 6

Tachometer housing Bolt 1 M6x1.0 5 0,5

Stopper lever Bolt 1 M6x1.0 14 1,4 LOCTITE screw glue

Shift pedal Bolt 1 M6x1.0 15 1,5

Thermo unit

Rotor 1 ~ 15 1,5Nut 1 M12x1.25 80 8

SPECDEFINITION OF UNITS

2-12

CHASSIS

TightenedThread torque

Parts to be tightened size Nm m•kg Remarks

Engine stay (Top) and frame M10 30-35 3,0-3,5

Cylinder head stay (Top) and frame M10 30-35 3,0-3,5

Bottom screw (front) engine and frame M10 60-78 6,0-7,8

Bottom screw (front) engine to swingarm M10 30-35 3,0-3,5

Steering nut M25 120-155 12,0-15,5 Steering must turn smoothly and without free play

Fuel cock lever M6 5~8 0,5~0,8

Upper bracket and meter holder M6 5~8 0,5~0,8

Rear bolt fuel tank to frame M6 7,5-12 0,75-1,2

Footrest security pins — Completely bend

Front brake holder M10 2~3 0,2~0,3

Front brake pipe M10 23-37 2,3-3,7

Handlebar holder bolts to handlebars M8 5~8 0,5~0,8

Main switch M6 7~12 0,7~1,2 Security allen bolt(with central pin)

Top holder bolts to suspension tubes M8 12~28 1,2~2,8

Sidestand nut M8 20-32 2,0-3,2

Rear brake lever M8 7,5-12 0,75-1,2

Rear master cylinder to holder M6 7,5-12 0,75-1,2

Brake pipe bolt M10 23-37 2,3-3,7

Security pin rear brake lever to pump — Completely bend

Pivot shaft M15 80-100 8,0-10,0

Swingarm to connecting arm M13 45-70 4,5-7,0

Connecting arm relay arm M13 45-70 4,5-7,0

Relay arm to frame M13 45-70 4,5-7,0

Damper to frame M10 30-35 3,0-3,5

Damper to relay arm M10 30-35 3,0-3,5

Swingarm end bolts — 2~4 0,2-0,4

Driven sprocket M8 32-37 3,2-3,7

Rear wheel axle nut M17 80-100 8,0-10,0 Check that the pin is bent

Front brake caliper to outer tube M10 31-49 3,1-4,9

Front wheel axle M15 45-70 4,5-7,0

Exhaust to cylinder head M8 15-20 1,5-2,0

Exhaust assy 1 to central exhaust pipe M8 8~12 0,8-1,2

Central exhaust pipe to muffler M8 8~12 0,8-1,2

Muffler and central pipe to frame holder M8 38-42 3,8-4,2

Clutch lever pivot nut M6 5~8 0,5-0,8

Front brake pivot lever nut M6 5~8 0,5-0,8

Front brake lever adjusting nut M6 5~8 0,5-0,8

Security nuts M6 7,5-12 0,75-1,2

Chain puller M6 18-28 1,8-2,8

shift shaft nut M6 8~12 0,8-1,2

Rear footrest holder M8 17-22 1,7-2,2

Bottom bolts inner holder to tube M8 20-25 2,0-2,5

SPECCOOLANT FLOW CHART

2-13

COOLANT FLOW CHART

Water pump Crankcase cover Crankcase Cylinder

Cylinder head

Bypass hose Thermostatic valve(Thermostatic valve)

Outlet hose Radiator Inlet hose

Coolant cold (Less than 65°C (149°F))Coolant hot (165°(149°F) or more)

SPECLUBRICATION POINTS AND LUBRICANT TYPES

2-14

EAS00031

ENGINE

Lubrication points (part name) Lubricant Type

Oil seal lips (All) Apply lightweight lithium-soap base grease

O-Rings (All) Apply lightweight lithium-soap base grease

Bearing retainer

Crankshaft bearings (Left and center) Apply engine oil

Needle bearings (Connecting rod) Apply engine oil

Main axle bearings Apply gear oil

Drive axle bearings Apply gear oil

Push lever bearings Apply gear oil

Crank pins Apply engine oil

Piston rings - piston pins and pistons Apply engine oil

Power valve holder Apply lightweight lithium-soap base grease

Impeller shaft (water pump) Apply gear oil

Warm shaft (Autolube pump) Apply engine oil

Kick idle gear Apply gear oil

Kick axle Apply gear oil

Primary driven gear (clutch housing) Apply gear oil

Push rod Apply gear oil

Push lever axle Apply gear oil

Sliding gear (Transmission) Apply molybdenum disulfide grease

Free movement gear (Transmission) Apply molybdenum disulfide grease

Guide bar (Shift forks) Apply gear oil

Crankcase mating surfaces Yamaha bond no.4

SPECLUBRICATION POINTS AND LUBRICANT TYPES

2-15

EAS00032

CHASSIS

Lubrication points (part name) Lubricant Type

Ball bearing (Steering shaft) Apply lightweight lithium-soap base grease

Bearing (Steering shafts) Apply lightweight lithium-soap base grease

Oil seal clutch to lever Apply lightweight lithium-soap base grease

Clutch lever axle free play Apply lightweight lithium-soap base grease

Throttle guide bar Apply lightweight lithium-soap base grease

Oil seal throttle wire to guide Apply lightweight lithium-soap base grease

Front brake lever axle free play Apply lightweight lithium-soap base grease

Footrests free play Apply lightweight lithium-soap base grease

Rear footrests free play (ball and axle) Apply lightweight lithium-soap base grease

Swingarm axle to frame Apply lightweight lithium-soap base grease

Relay arm to swingarm Apply lightweight lithium-soap base grease

Connecting rods Apply lightweight lithium-soap base grease

Engine holder to cylinder head Apply lightweight lithium-soap base grease

Rear brake lever pivot Apply lightweight lithium-soap base grease

Sidestand pivot Apply lightweight lithium-soap base grease

Oil seal lip (front wheel) Apply lightweight lithium-soap base grease

Front wheel axle outer surface Apply lightweight lithium-soap base grease

Oil seal lip (rear wheel) Apply lightweight lithium-soap base grease

Rear wheel axle outer surface Apply lightweight lithium-soap base grease

SPECCABLE ROUTING

2-16

CABLE ROUTING

Clutch wire Right turn signal lead Left turn signal lead Throttle cable Indicator light wire lead Meter wire lead Headlight bulb wire Handle wire lead (right)

A Cover with cap after connecting wires.B Route the installation between lower brac-

ket and headlight bottom holder.C Clamp connection wire.

A

B

C

SPECCABLE ROUTING

2-17

CABLE ROUTING

Master cylinder Front brake hose Wire throttle Clutch sw wire lead SW handle wire lead (left) Clip A.I.S. Pipe overflow Pipe to air filter Pipe I License light wire lead Oil gauge

A Turn the hose to obtain the desired angle.B Route clutch wire first for the inside, after

route the throttle wire.C Clamp handle wire lead (L).D Clamp handle wire lead (R).E Clamp pipe overflow to the frame clamp.F Hold hoses on chassis clamp.G Cover with cap after connecting wires.H Route brake/tail light wire through rear

mudguard hole.I Clamp rear turning light wire (R) and

tail/brake lights wire to frame clamp.J Route the following cables through the

frame bracket:rear turning signal wire (R), rear turning sig-nal wire (L), tail/brake wire, license lightwire.

B

D E

C

F

G J H

A

I

SPECCABLE ROUTING

2-18

CABLE ROUTING

Main switch wire lead Pipe overflow Ignition coil Horn Flasher relay Air vent hose Fuel pipe Oil pipe

A Route speedometer cable to frame guide.B Route pipe overflow behind engine holder.C Screw ground wire and rectifier with the

same bolt.D Pipe overflow pass behind oil hose.E Route carburetor breather hose between

rear shock absorber and swingarm.F Route pipe overflow between rear shock

absorber and swingarm.

C

A

B

D E F

SPECCABLE ROUTING

2-19

CABLE ROUTING

Front brake hose Clutch wire Ignition coil Throttle wire Therm switch Sidestand switch wire lead Oil hose

A Route brake hose through the guide.B Clamp clutch wire.C Guide wire (chassis): SW handle wire lead

(R), SW handle wire lead (L), clutch SWwire lead, front stop SW wire lead, wirethrottle, wire clutch.

D Insert installation clip to frame hole.E Route clutch wire through the guides.F Connect ground on the front part of the

coil. Install screw and wire terminal.G Cover thermo-switch with cap.H Insert connector to frame clamp (X3).I Install clamp with open part to the upper

side. Route pipe overflow and pipe Ithrough clamp.

J Route sidestand switch through brackets.The lead must have no slack at distance“X”.

K Route oil hose through clamp under thebattery.

L Route sidestand switch through the lowerpart of the air filter.

A

D

C I

F H

E

G

L

K

J

B

x

CHKADJ

3

CHAPTER 3PERIODIC CHECKS AND ADJUSTMENTS

INTRODUCTION/PERIODIC MAINTENANCE/LUBRICATION …………………3-1

ENGINE ……………………………………………………………………………3-2Y.P.V.S. CABLE ADJUSTMENT ………………………………………………3-2IDLE SPEED ADJUSTMENT …………………………………………………3-3THROTTLE CABLE FREE PLAY ADJUSTMENT……………………………3-4CARBURETOR CABLE FREE PLAY ADJUSTMENT ………………………3-5AUTOLUBE PUMP STROKE ADJUSTMENT ………………………………3-6AUTOLUBE PUMP AIR BLEEDING …………………………………………3-6SPARK PLUG INSPECTION …………………………………………………3-7IGNITION TIMING CHECK ……………………………………………………3-8ENGINE OIL LEVEL INSPECTION …………………………………………3-9TRANSMISSION OIL LEVEL INSPECTION ………………………………3-11TRANSMISSION OIL REPLACEMENT ……………………………………3-11CLUTCH ADJUSTMENT ……………………………………………………3-12AIR FILTER CLEANING………………………………………………………3-16CARBURETOR JOINT INSPECTION ………………………………………3-18FUEL LINE INSPECTION ……………………………………………………3-18CHECKING THE CRANKCASE BREATHER HOSE ………………………3-18EXHAUST SYSTEM INSPECTION …………………………………………3-19ENGINE OIL LINE INSPECTION ……………………………………………3-19COOLANT LEVEL INSPECTION ……………………………………………3-19COOLANT REPLACEMENT…………………………………………………3-20COOLING SYSTEM INSPECTION …………………………………………3-23

CHASSIS …………………………………………………………………………3-24FRONT BRAKE ADJUSTMENT ……………………………………………3-24REAR BRAKE ADJUSTMENT ………………………………………………3-24BRAKE FLUID INSPECTION ………………………………………………3-25BRAKE PAD INSPECTION …………………………………………………3-27BRAKE LIGHT SWITCH ADJUSTMENT …………………………………3-27BRAKE HOSE INSPECTION ………………………………………………3-28DRIVE CHAIN SLACK ADJUSTMENT ……………………………………3-28DRIVE CHAIN LUBRICATION ………………………………………………3-30STEERING HEAD ADJUSTMENT …………………………………………3-30FRONT FORK INSPECTION ………………………………………………3-32REAR SHOCK ABSORBER ADJUSTMENT ………………………………3-33TIRE INSPECTION……………………………………………………………3-34WHEEL INSPECTION ………………………………………………………3-36CABLE INSPECTION AND LUBRICATION ………………………………3-37

ELECTRICAL ……………………………………………………………………3-39BATTERY INSPECTION ……………………………………………………3-39FUSE INSPECTION …………………………………………………………3-42HEADLIGHT BULB REPLACEMENT ………………………………………3-43HEADLIGHT BEAM ADJUSTMENT ………………………………………3-44

CHKADJ

CHKADJ

INTRODUCTION/PERIODIC MAINTENANCE/LUBRICATION INTERVALS

3-1

PERIODIC CHECKS AND ADJUSTMENTSNOTE:• The annual checks must be performed every year, except if a kilometer-based maintenance is performed instead.• From 30000 km, repeat the maintenance intervals starting from 6000 km.• Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools, data and tech-

nical skills.

ODOMETER READING ANUAL( x 1.000 km) CHECK

No ITEM CHECK OR MAINTENANCE JOB 1 6 12 18 24

1 * Fue line Check fuel hoses and vacuum hose for cracks or damage. √ √ √ √ √

2 Spark plug • Check condition.√ √• Clean and regap.

• Replace. √ √

3 Air filter element • Clean. √ √• Replace. √ √

4 Clutch • Check operation.√ √ √ √ √• Adjust.

5 * Front brake • Check operation and adjust brake lever √ √ √ √ √ √free play.

• Replace brake shoes. Whenever worn to the limit

6 * Rear brake • Check operation, fluid level and vehicle √ √ √ √ √ √for fluid leakage.

• Replace brake pads. Whenever worn to the limit

7 * Brake hoses • Check for cracks or damage. √ √ √ √ √• Replace. Every 4 years

8 * Wheels • Check runout, spoke tightness and for damage. √ √ √ √

• Tighten spokes if necessary.

9 * Tires • Check tread depth and for damage.• Replace if necessary. √ √ √ √ √• Check air pressure.• Correct if necessary.

10 * Wheel • Check bearing for looseness or damage. √ √ √ √bearings

11 * Swingarm • Check operation and for excessive play. √ √ √ √• Lubricate with lithium-soap-based grease. Every 24,000 km

12 Drive chain • Check chain slack.• Make sure that the rear wheel is properly aligned. Every 500 km and after washing• Clean and lubricate. the motorcycle or riding in the rain

13 * Steering • Check bearing play and steering for roughness. √ √ √ √ √bearings • Lubricate with lithium-soap-based grease. Every 24,000 km

14 * Chassis • Make sure that all nuts, bolts and screws √ √ √ √ √fasteners are properly tightened.

15 Sidestand • Check operation. √ √ √ √ √• Lubricate.

16 * Sidestand • Check operation. √ √ √ √ √ √switch

17 * Front fork • Check operation and for oil leakage. √ √ √ √

18 * Shock absorber • Check operation and shock absorber √ √ √ √assembly for oil leakage.

19 * Rear suspension • Check operation. √ √ √ √relay arm and • Lubricate with lithium-soap-based grease. √ √connecting arm pivoting points

20 * Carburetor • Check starter (choke) operation. √ √ √ √ √ √• Adjust engine idling speed.

21 Engine oil • Change. √ When the oil change indicator light comes on(every 3,000 km)

• Check oil level and vehicle for oil leakage. Every 3,000 km √

22 * Autolube pump • Check operation. √ √ √ √• Bleed if necessary.

23 Transmission oil • Check oil level. √ √ √ √ √ √• Change. √ √

24 * Cooling system • Check coolant level and vehicle for coolant leakage.

√ √ √ √ √

• Change. Every 3 years

25 * Throttle grip • Check operation and free play.housing and • Adjust the throttle cable free play if necessary. √ √ √ √ √cable • Lubricate the throttle grip housing and cable.

CHKADJY.P.V.S. CABLE ADJUSTMENT

3-2

2

1

ENGINEY.P.V.S. CABLE ADJUSTMENT1. Remove• pulley cover (power valve)

2. Turn on the main switch

NOTE

If the Y.P.V.S. Doesn’t operate, refeer to the“Y.P.V.S. SYSTEM” in CHAPTER 9

3. Check• alignment mark

Not aligned Adjust the Y.P.V.S. Cables

4. Adjust• Y.P.V.S. Cables

Adjustments steps:• Loosen both locknuts and turn in both

adjusters .• Insert a pin [fl 0,16 in.)] through the aligning

indent in the pulley and into the hole to lockthe pulley.

• Turn both adjusters, counterclockwise sothat the cable free play becomes zero mm(zero in.) with fingers.

• Turn both adjusters 1/4 turn clockwise.• Tighten the locknuts.

• Turn on the main switch and check taht thealignment mark is aligned.If not, rpeat the above steps.

5. Install• pulley cover (Power valve)

1

Locknuts:8 Nm (0,8 m•kg, 5,8 ft•lb)

1 Locknuts:7 Nm (0,7 m•kg, 5,1 ft•lb)

2

1

3

CHKADJIDLE SPEED ADJUSTMENT

3-3

IDLE SPEED ADJUSTMENT1. Adjust:• engine idle speed

EAS00054

ADJUSTING THE ENGINE IDLING SPEED

NOTE:

Prior to adjusting the engine idling speed, theair filter element should be clean, and the engi-ne should have adequate compression.

1. Start the engine and let it warm up for seve-ral minutes.

2. Connect:• engine tachometer

(onto the spark plug lead of cylinder #1)

3. Check:• engine idling speed

Out of specification Adjust.

4. Adjust:• engine idling speed

a. Turn the pilot screw in or out until it islightly seated.

b. Turn the pilot screw out the specified num-ber of turns.

c. Turn the throttle stop screw in directiona or b until the specified engine idlingspeed is obtained.

5. Adjust:• throttle cable free play

Refer to “ADJUSTING THE THROTTLECABLE FREE PLAY”.

Engine tachometer90890-03113

Engine idling speed1250 ~ 1450 r/min

Direction a Engine idling speed isincreased.

Direction b Engine idling speed isdecreased.

Throttle cable free play (at theflange of the throttle grip)

3 ~ 5 mm (0,11 ~ 0,18 in)

Pilot screw setting1/4 turns out

2

1

(a)

(b)

CHKADJADJUSTING THE THROTTLE CABLE FREE PLAY

3-4

EAS00058

ADJUSTING THE THROTTLE CABLE FREEPLAY

NOTE:

Prior to adjusting the throttle cable free play,the engine idling speed and carburetor synch-ronization should be adjusted properly.

1. Check:• throttle cable free play a


2. Adjust:• throttle cable free play

Handlebar sidea. Loosen the locknut .b. Turn the adjusting nut in direction a or

b until the specified throttle cable free playis obtained.

c. Tighten the locknut.

ss WARNING

After adjusting the throttle cable free play,start the engine and turn the handlebar tothe right or left to ensure that this does notcause the engine idling speed to change.

Throttle cable free play (at theflange of the throttle grip)

3 ~ 5 mm (0,11 ~ 0,19 in)

12

Direction a Throttle cable free playis increased.

Direction b Throttle cable free playis decreased.

CHKADJ

ADJUSTING THE THROTTLE CABLE FREE PLAY/CARBURETOR CABLE FREE PLAY ADJUSTMEN

3-5

CARBURETOR CABLE FREE PLAYADJUSTMENT

NOTE:

Before adjusting carburetor cable, throttlecable free play should be adjusted.

1. Pull back the adjuster cover.

2. Check:• carburetor cable free play a

Out of specification adjust

3. Adjust:• Caburetor free play

Adjustment steps:• Loosen the locknut • Turn the adjuster in or out until the

correct free play obtained.

• Tighten the locknuts

4. Push in the adjuster cover.

Carburetor Cable Free Play:1,0 mm (0,04 in)

Turn in Free play is increased.Turn out Free play is decreased.

2

3

CHKADJ

AUTOLUBE PUMP STROKE ADJUSTMEN/AUTOLUBE PUMP AIR BLEEDING

3-6

AUTOLUBE PUMP STROKE ADJUSTMENT1. Remove:• Autolube pump cover

2. Adjusting markNot aligned Adjust the Autolube Pump

3. Adjust• Autolube pump

The adjusting marks a and b has to matchwhen the throttle cable free play ends.

Adjustment steps:a. Loosen the locknut b. Turn the adjuster until the correct adjust-

ment is obtainedc. Tighten the locknut.

AUTOLUBE PUMP AIR BLEEDING

NOTE:

The Autolube pump and delivery lines must bebleed on the following ocasions:• Setting up a new motorcycle out of the

crate.• Whenever the oil tank has run dry.• Whenever any portion of the engine oil sys-

tem is disconnected.

1. Remove:• autolube pump cover

2. Fill:• oil tank

Yamaha il 2T or Air-Cooled2 Stroke Engine Oil

1

(a) (b)

1

1

1

CHKADJ

AUTOLUBE PUMP AIR BLEEDING/CHECKING THE SPARK PLUG

3-7

3. Air blled:• pump case and/or oil pipe

Air bleeding steps• Remove the bleed cap • Start the engine.• Keep the oil running out until air bubbles

dissapear.• Keep the engine running at about

2.000r/min for two minutes or so• When air bubbles are expelled completely,

install the bleed cap.

NOTE:

Place a rag or oil pan under the autolube pumpto catch the oil.

EAS00060

CHECKING THE SPARK PLUG1. Disconnect:• spark plug cap

2. Remove:• spark plug

CAUTION

Before removing the spark plug, blow awayany dirt accumulated in the spark plug wellwith compressed air to prevent it fromfalling into the cylinder.

3. Check:• spark plug type

Incorrect Change.

4. Check:• electrode

Damage/wear Replace the spark plug.• insulator

Abnormal color Replace the spark plug.Normal color is medium-to-light tan.

5. Clean:• spark plug

(with a spark plug cleaner or wire brush)

Spark plug type (manufacturer)BR8ES (NGK)

1

CHKADJ

CHECKING THE SPARK PLUG/CHECKING THE IGNITION TIMING

3-8

6. Measure:• spark plug gap a

(with a wire Thickness gauge)Out of specification Regap.

7. Install:• spark plug

NOTE:

Before installing the spark plug, clean thespark plug and gasket surface.

8. Connect:• spark plug cap

EAS00064

CHECKING THE IGNITION TIMING

NOTE:

Prior to checking the ignition timing, check thewiring connections of the entire ignition sys-tem. Make sure all connections are tight andfree of corrosion.

1. Remove:• crankcase cover (left)

2. Connect:• timing light• engine tachometer

(onto the spark plug lead of cylinder #1)

Spark plug gap0,7-0,8mm (0,0276-0,03315in)

Spark plug20Nm (2,0m·kg, 14ft·lb)

Timing light90890-03141

Engine Tachometer90890-03113

CHKADJ

CHECKING THE IGNITION TIMING/ENGINE OIL LEVEL INSPECTION

3-9

3. Check:• ignition timing

a. Start the engine, warm it up for severalminutes, and then let it run at the specifiedengine idling speed.

b. Check that the stationary pointer is withinthe firing range on the generator rotor.Incorrect firing range Check the ignitionsystem.

NOTE:

The ignition timing is not adjustable.

4. Install:• Crankcase cover (left)

ENGINE OIL LEVEL INSPECTION1. Check• oil level

oil level low Adjust sufficient oil

Engine idling speed1250-1450 r/min

Recommended oil:Yamaha Oil 2T or Air Cooled 2stroke Engine Oil

Oil Tank Capacity:1,3 L

CHKADJENGINE OIL LEVEL INSPECTION

3-10

0

km/h

4060 80

100

120

130

20

y

0 0 0 0 1 5

0 0 0 8

b j

z N

CAUTION

Always use the same type of engine oil;mixing oils may result in a harmful chemicalreaction and lead to poor performance.

“OIL” Indicator light

OIL WARNING LIGHT CHECKING METHOD

Main Switch “ON”

Gears in “NEUTRAL”

Oil warning indicator light does not come on

Refeer to CHAPTER 8“SIGNAL SYSTEM”

Oil warning indicator light come on

Shift into gear

Oil warning indicator light does not come on

Oil warning indicator light come on

Supply engine oilEngine oil level and electrical circuit are OK

1

CHKADJ

TRANSMISSION OIL LEVEL INSPECTION/TRANSMISSION OIL REPLACEMENT

3-11

TRANSMISSION OIL LEVEL INSPECTION1. Inspect:• transmission oil level

Oil level low Add sufficient oil

Transmission oil level steps:• Place the machine on a level surface.• Warm up the engine for several minutes and

stop it.• Visually check the oil level through the level

window .

NOTE:

• Check the oil level just one minute afterstopping the engine.

• The oil should e confirmed between maxi-mum and minimum marks.

• If the oil level is lower, add sufficient oil toraise it to the proper level.

• Do not add any chemical additives.Transmission oil also lubricates the clutchand additives could cause clutch slippage.

• Be sure no foreign material enters thecrankcase.

TRANSMISSION OIL REPLACEMENT1. Warm up the engine for several minutes.2. Place a container under the engine.3. Remove:• oil filler cap • drain pulg

drain transmission oil.

NOTE:

Drain the transmission oil with the motorcycleslightly inclined to the right.

4. Inspect:• gasket (Drain plug) • O-Ring (oil filter cap)

Damage Replace

Recommended oil:SAE10W30 Type SE Motor Oil

13

2

1

2

2

CHKADJ

TRANSMISSION OIL REPLACEMENT/ADJUSTING THE CLUTCH CABLE FREE PLAY

3-12

5. Install:• Drain plug

6. Fill:• Crankcase

CAUTION

• Do not add any chemical additives.Transmission oil also lubricates theclutch and additives could cause clutchslippage.

• Be sure no foreign materials enters thecrankcase.

7. Install:• Oil filler cap

8. Inspect:• Oil leaks• Oil level

NOTE:

Wipe off any oil spilled on the crankcase.

EAS00078

ADJUSTING THE CLUTCH CABLE FREEPLAY1. Check:• clutch cable free play


2. Adjust:• clutch cable free play

Handlebar sidea. Loosen the locknut .b. Turn the adjusting bolt in direction a or

b until the specified clutch cable free playis obtained.

Clutch cable free play (at the endof the clutch lever)

10-15mm (0,34-0,59in.)1 2

3

Spark plug15Nm (1,5m·kg, 11ft·lb)

Recomended oil:SAE 10W30 Type SE Motor Oil

Periodic oil change:0,75L

CHKADJADJUSTING THE CLUTCH CABLE FREE PLAY

3-13


NOTE:

If the specified clutch cable free play cannotbe obtained on the handlebar side of thecable, use the adjusting nut on the engineside.

Engine sidea. Loosen the locknuts .b. Turn the adjusting bolt in direction a or

b until the specified clutch cable free playis obtained.

c. Tighten the locknuts.

Mechanism adjustment1. Remove:• Brush guard

2. Loosen:• Locknuts

3. Turn the adjusters .

4. Drain:• Coolant

Refeer to the “COOLANT REPLACEMENT”section.

5. Disconnect:• Outlet hose (radiator)

6. Remove:• Screw (Water outlet pipe)

Direction a Clutch cable free play isincreased.

Direction b Clutch cable free play isdecreased.

Direction a Clutch cable free play isincreased.

Direction b Clutch cable free play isdecreased.

1 1

1 2

1

2


3-14

7. Disconnect:• Autolube pump cable • Autolube pump hose

Refer to the “AUTOLUBE PUMP CABLEAND HOSE” section in the CHAPTER 4.

8. Drain:• Transmission oil

Refer to the ”TRANSMISSION OIL REPLA-CEMENT” section.

9. Remove:• Return spring • Bolt (master cylinder) • Brake pedal • Crankcase cover (Right)

10. Adjust:• Adjuster (push rod=1)

Adjustments steps:• Loosen the locknut • Move the push lever toward the front

with you finger until it stops.• With the push lever in this position turn the

adjuster to align the mark on the endof the push lever with the mark (protube-rance) on the crankcase.

• Tighten the locknut .

11. Install:• crankcase cover (right)• brake pedal• return spring

Locknut8 Nm (0,8 m • kg, 5,8 ft • lb)

Screw (crankcase cover):8 Nm (0,8 m • kg, 5,8 ft • lb)

Drain plug (Oil):15 Nm (1,5 m • kg, 11 ft • lb)

Drain plug (coolant):10 Nm (1,0 m • kg, 7,2 ft • lb)

Screw (brake pedal):20 Nm (2,0 m • kg, 14 ft • lb)

2

1

2

1 3

4

12

3

5

4


3-15

NOTE:

• When installing the crankcase cover, engagethe autolube pump drive gear with its drivengear as slowly turn the autolube pump shaft.

• Tighten the screws (Crankcase cover) instage, using a crisscross pattern.

• Before installing the brake pedal apply thelithium soap base grease to the brake pedalpivot shaft.

12. Install:• Gasket (Autolube pump cover)

13. Connect:• Autolube pump hoses • Autolube pump cable

14. Install:• Screw (Water outlet pipe)

15. Connect:• Outlet hose (Radiator)

16. Adjust:• Clutch cable free play

Refer to the “Cable free play adjustment”section.”

17. Install:• Brush guard

18. Fill:• CrankcaseRefer to the “TRANSMISSION OIL REPLA-CEMENT” section.

19. Fill:• Radiator • Reservoir tank (radiator)

Refer to the “COOLANT REPLACEMENT”section.

Screw (Water outlet Pipe)8 Nm (0,8 m • kg, 5,8 ft • lb)

Recommended oil:SAE10W30 Type SE Motor Oil

Periodic Oil Change0,75 L

Total amount:0,92 L

1

2

3

1

1

CHKADJ

ADJUSTING THE CLUTCH CABLE FREE PLAY/CLEANING THE AIR FILTER ELEMENT

3-16

20. Air bleeding:• Autolube pump

Refer to the “AUTOLUBE PUMP AIR BLEE-DING section.

21. Install:• Autolube pump cover

EAS00089

CLEANING THE AIR FILTER ELEMENT

NOTE:

On the bottom of the air filter case is a checkhose . If dust or water or both collects in thishose, clean the air filter element and air filtercase.

1. Remove:• Side cover (left)

2. Remove:• air filter case cover screws • air filter assembly

Slide out guide together with element

3. Clean:• air filter element

(with solvent)

ss WARNING

Never use low flash point solvents, such asgasoline, to clean the air filter element.Such solvents may cause a fire or an explo-sion.

NOTE:

After cleaning, gently squeeze the air filter ele-ment to remove the excess solvent.

Screw (autolube pump cover)5 Nm (0,5 m • kg, 3,6 ft • lb)

1

1

1

1

CHKADJCLEANING THE AIR FILTER ELEMENT

3-17

CAUTION

Do not twist the air filter element whensqueezing it.

4. Check:• air filter element

Damage Replace.

5. Apply the recommended oil to the entiresurface of the air filter element and squeezeout the excess oil. The air filter elementshould be wet but not dripping.

6. Install:• air filter element• air filter element (to element guide)

NOTE:

Install the washer with its bent fringeupwards as shown.

• Air filter assembly.Slide in guide to air case.

CAUTION

Be sure to insert the element guide into thefilter case with its handle located closeto you, and also pay attention to the sealsponge for damage.

7. Install:• Side cover (left)

Recommended oilSAE10W30

1

1 2

1

2

CHKADJ

CARBURETOR JOINT INSPECTIONS /FUEL LINEINSPECTION/CHECKING THE CRANKCASE BREATHER HOSE

3-18

CARBURETOR JOINT INSPECTION1. Inspect:• Carburetor joint

Crack-damage ReplaceRefer to the “REED VALVE” section in chap-ter 7 for replacement

2. Check the tightening torque of the carbure-tor joint securing bolts.

FUEL LINE INSPECTION1. Inspect:• Fuel hose

Cracks-damage replaceLoose connection Connect properly

EAS00098

CHECKING THE CRANKCASE BREATHERHOSE1. Check:• crankcase breather hose

Cracks/damage Replace.Loose connection Connect properly.

CAUTION

Make sure the crankcase breather hose isrouted correctly.

Bolt (Carburetor joint)8 Nm (0,8 m • kg, 5,8 ft • lb)

1

1

CHKADJ

EXHAUST SYSTEM INSPECTION/ENGINE OIL LINEINSPECTION/ COOLANT LEVEL INSPECTION

3-19

FULL

LOW

EXHAUST SYSTEM INSPECTION1 .Inspect:• Gasket (exhaust pipe) • Joint (Silencer)

Damage ReplaceExhaust gas leakage Repair

• Exhaust pipe • Silencer

Cracked/Dent/Damage Repair or replace

2. Tighten:• Exhaust pipe• Muffler

ENGINE OIL LINE INSPECTION1. Remove:• Autolube pump cover

2. Inspect:• Oil hose • Oil delivery hose

Cracks-damage replaceLoose connection Connect properly


COOLANT LEVEL INSPECTION1. Place the machine in a level surface.2. Remove:• Side cover (left)

3. Inspect:• Coolant level

Coolant level is under “Low” level line Add soft water (tap water). Coolant reservoir tank.

Nut (Exhaust pipe)18 Nm (1,9 m • kg, 13 ft• lb)

Screw (Muffler Joint)10 Nm (1,0 m • kg, 7,2 lb • ft)

Bolts 10 Nm (1,0 m • kg, 7,2 lb • ft)

Screw (autolube pump cover)7 Nm (0,7 m • kg, 5,1 ft • lb)

4

2

7

1

53

1

2

1

2

CHKADJ

COOLANT LEVEL INSPECTION/CHANGING THE COOLANT

3-20

ss WARNING

Do not remove the radiator cap when theengine is hot.

CAUTION

Hard water or salt water is harmful to theengine parts; use boiled or distilled water ifyou can’t get soft water.

4. Add:• Soft water (tap water)

Until the coolant level reaches “FULL” levelline.

5. Install:• Side cover (Left).

EAS00105

CHANGING THE COOLANT1. Remove:• side covers (left and right)• exhaust pipe.

2. Disconnect:• coolant reservoir hose

3. Drain:• coolant

(from the coolant reservoir)4. Remove:• radiator cap

ss WARNING

A hot radiator is under pressure. Therefore,do not remove the radiator cap when theengine is hot. Scalding hot fluid and steammay be blown out, which could causeserious injury. When the engine has cooled,open the radiator cap as follows:Place a thick rag or a towel over the radia-

Reservoir tank capacityTotal

0,30 LFrom “LOW” to “FULL” Level

0,24 L

FULL

LOW

1

CHKADJCHANGING THE COOLANT

3-21

tor cap and slowly turn the radiator capcounterclockwise toward the detent toallow any residual pressure to escape.When the hissing sound has stopped, pressdown on the radiator cap and turn it coun-terclockwise to remove.

The following procedure applies to all of thecoolant drain bolts and copper washers.5. Remove:• coolant drain bolt (engine)

(along with the copper washer)6. Drain:• coolant

(from the engine and radiator)7. Check:• copper washer (coolant drain bolt-engi-

ne )8. Install:• coolant drain bolt (engine)

9. Connect:• coolant reservoir hose

10. Fill:• cooling system

(with the specified amount of the recom-mended coolant)

Handling notes for coolantCoolant is potentially harmful and should behandled with special care.

ss WARNING

• If coolant splashes in your eyes, tho-roughly wash them with water and con-sult a doctor.

• If coolant splashes on your clothes,quickly wash it away with water and then

Coolant drain bolt (engine):10Nm (1.0 m·kg, 7,2lb·ft)

Recommended antifreezeHigh-quality ethylene glycol anti-freeze containing corrosion inhi-bitors for aluminum engines

Mixing ratio1:1 (antifreeze:water)

QuantityTotal amount

0,92 L (0,81 Imp qt, 0,97 US qt)Coolant reservoir capacity

0,30 L (0,26 Imp qt, 0,32 US qt)From minimum to maximum levelmark

0,24 L (0,21 Imp qt, 0,25 US qt)

1

2

1

CHKADJCHANGING THE COOLANT

3-22

with soap and water.• If coolant is swallowed, induce vomiting

and get immediate medical attention.

CAUTION

• Adding water instead of coolant lowersthe antifreeze content of the coolant. Ifwater is used instead of coolant check,and if necessary, correct the antifreezeconcentration of the coolant.

• Use only distilled water. However, if disti-lled water is not available, soft watermay be used.

• If coolant comes into contact with pain-ted surfaces, immediately wash themwith water.

• Do not mix different types of antifreeze.

11. Install:• radiator cap

12. Fill:• coolant reservoir

(with the recommended coolant to themaximum level mark a )

13. Install:• coolant reservoir cap

14. Start the engine, warm it up for severalminutes, and then stop it.

15. Check:• coolant level

Refer to “CHECKING THE COOLANTLEVEL”.

NOTE:

Before checking the coolant level, wait a fewminutes until the coolant has settled.

16. Install:• Exhaust pipe• Side covers (left and right)

FULL

LOW

Nut (Exhaust pipe):18 Nm (1,8 m • kg, 13 ft • lb)

Bolt (Stay):10 Nm (1,0 m • kg, 7,2 ft • lb)

Screw (Muffler Joint):10 Nm (1,0 m • kg, 7,2 ft • lb)

(a)

31

1

CHKADJCOOLING SYSTEM INSPECTION

3-23

COOLING SYSTEM INSPECTION1. Inspect:• radiator • inlet hose • outlet hose • water outlet pipe

cracks-damage ReplaceRefer to the “COOLING SYSTEM” sectionins CHAPTER 6.

1

4

CHKADJ

ADJUSTING THE FRONT BRAKE/ADJUSTING THE REAR BRAKE

3-24

EAS00108

CHASSISADJUSTING THE FRONT BRAKE1. Check:• brake lever free play


2. Adjust:• brake lever free play

a. Loosen the locknut .b. Turn the adjusting bolt in direction a or

b until the specified brake lever free play isobtained.


ss WARNING

A soft or spongy feeling in the brake levercan indicate the presence of air in the brakesystem. Before the vehicle is operated, theair must be removed by bleeding the brakesystem. Air in the brake system will consi-derably reduce braking performance andcould result in loss of control and possiblyan accident. Therefore, check and, if neces-sary, bleed the brake system.

CAUTION

After adjusting the brake lever free play,make sure there is no brake drag.

EAS00111

ADJUSTING THE REAR BRAKE1. Check:• brake pedal position

(distance a from the top of the rider foo-trest to the top of the brake pedal)Out of specification Adjust.

Brake lever free play (at the end ofthe brake lever)

2 ~ 5mm (0,08 ~ 0,20in)

Direction a Brake lever free play isincreased.

Direction b Brake lever free play isdecreased.

12

3

Brake pedal position (below thetop of the rider footrest)

15 mm (0,6 in)

(a)(b)

1

CHKADJ

ADJUSTING THE REAR BRAKE/CHECKING THE BRAKE FLUID LEVEL

3-25

2. Adjust:• brake pedal position

a. Loosen the locknut .b. Turn the adjusting bolt in direction a or

b until the specified brake pedal position isobtained.

ss WARNING

After adjusting the brake pedal position,check that the end of the adjusting bolt pro-trudes 2 mm (0,08 in) from the bottom of theset nut.


ss WARNING

A soft or spongy feeling in the brake pedalcan indicate the presence of air in the brakesystem. Before the vehicle is operated, theair must be removed by bleeding the brakesystem. Air in the brake system will consi-derably reduce braking performance andcould result in loss of control and possiblyan accident. Therefore, check and, if neces-sary, bleed the brake system.

CAUTION

After adjusting the brake pedal position,make sure there is no brake drag.

3. Adjust:• rear brake light switch

Refer to “ADJUSTING THE REAR BRAKELIGHT SWITCH”.

EAS00115

CHECKING THE BRAKE FLUID LEVEL1. Stand the motorcycle on a level surface.

NOTE:

• Place the motorcycle on a suitable stand.• Make sure the motorcycle is upright.

Direction a Brake pedal is raised.Direction b Brake pedal is lowered.

2

1

1

FRONT A

3-26

2. Check:• brake fluid level

Below the minimum level mark Addthe recommended brake fluid to the properlevel.

A Front brakeB Rear brake

ss WARNING

• Use only the designated brake fluid.Other brake fluids may cause the rubberseals to deteriorate, causing leakageand poor brake performance.

• Refill with the same type of brake fluidthat is already in the system. Mixingbrake fluids may result in a harmful che-mical reaction, leading to poor brakeperformance.

• When refilling, be careful that water doesnot enter the brake fluid reservoir. Waterwill significantly lower the boiling pointof the brake fluid and could cause vaporlock.

CAUTION

Brake fluid may damage painted surfacesand plastic parts. Therefore, always cleanup any spilt brake fluid immediately.

NOTE:

In order to ensure a correct reading of thebrake fluid level, make sure the top of thebrake fluid reservoir is horizontal.

Recommended brake fluidDOT 4

1

REAR

CHKADJCHECKING THE BRAKE FLUID LEVEL

B

CHKADJ

CHECKING THE FRONT AND REAR BRAKE PADS/ADJUSTING THE REAR BRAKE LIGHT SWITCH

3-27

EAS00119

CHECKING THE FRONT AND REAR BRAKEPADSThe following procedure applies to all of thebrake pads.1. Remove:• Rubber plug

2. Operate the brake.3. Check:• front brake pad• rear brake pad

Wear indicators almost touch the brakedisc Replace the brake pads as a set.Refer to “REPLACING THE FRONT BRAKEPADS” and “REPLACING THE REARBRAKE PADS” in chapter 4.

A Front brakeB Rear brake

4. Install:• Rubber plug.

EAS00128

ADJUSTING THE REAR BRAKE LIGHTSWITCH

NOTE:

The rear brake light switch is operated bymovement of the brake pedal.The rear brake light switch is properly adjustedwhen the brake light comes on just before thebraking effect starts.

1. Check:• rear brake light operation timing

Incorrect Adjust.2. Adjust:• rear brake light operation timing

a. Hold the main body of the rear brakelight switch so that it does not rotate andturn the adjusting nut in direction a orb until the rear brake light comes on at theproper time.

1

1

FRONT

REAR

1

2

Direction a Brake light comes onsooner.

Direction b Brake light comes onlater.

A

B

CHKADJ

CHECKING THE FRONT AND REAR BRAKE HOSES/ADJUSTING THE DRIVE CHAIN SLACK

3-28

EAS00131

CHECKING THE FRONT AND REAR BRAKEHOSESThe following procedure applies to all of thebrake hoses and brake hose clamps.1. Check:• brake hose

Cracks/damage/wear Replace.2. Check:• brake hose clamp

Loose Tighten the clamp bolt.3. Hold the motorcycle upright and apply the

brake several times.4. Check:• brake hose

Brake fluid leakage Replace the dama-ged hose.Refer to “FRONT AND REAR BRAKES” inchapter 4.

EAS00139

ADJUSTING THE DRIVE CHAIN SLACK

NOTE:

The drive chain slack must be checked at thetightest point on the chain.

CAUTION

A drive chain that is too tight will overloadthe engine and other vital parts, and onethat is too loose can skip and damage theswingarm or cause an accident. Therefore,keep the drive chain slack within the speci-fied limits.

1. Stand the motorcycle on a level surface.

ss WARNING

Securely support the motorcycle so thatthere is no danger of it falling over.

NOTE:

Both wheels should be on the ground withouta rider on the motorcycle.

2. Move the rear wheel several times and findthe tightest position of drive chain.

CHKADJADJUSTING THE DRIVE CHAIN SLACK

3-29

3. Check:• drive chain slack a


4. Remove:• cotter pin

5. Loosen:• wheel axle nut

6. Adjust:• drive chain slack

a. Loosen both locknuts.b. Turn both adjusters in direction a or b

until the specified drive chain slack is obtai-ned.

NOTE:

• To maintain the proper wheel alignment,adjust both sides evenly.

• Push the rear wheel forward to make surethere is no clearance between the swin-garm end plates and the ends of the swin-garm.

c. Tighten the wheel axle nut to specification.

d. Tighten the locknuts to specification.

7. Install:• cotter pin

ss WARNING

Always use a new cotter pin.

CAUTION

Do not loosen the wheel axle nut after tigh-tening it to the specified torque. If the groo-ve in the wheel axle nut is not aligned withthe cotter pin hole in the wheel axle, tightenthe nut further until they are aligned.

Drive chain slack25 ~ 40 mm DT125X

(0,9842 ~ 1,5748 in)45 ~ 55 mm DT125RE

(1,7716 ~ 2,1653 in)

Wheel axle nut90 Nm (9.0 m • kg, 65 ft • lb)

Direction a Drive chain is tightened.Direction b Drive chain is loosened.

1

2

CHKADJ

LUBRICATING THE DRIVE CHAIN/CHEEKING AND ADJUSTING THE STEERING HEAD

3-30

09

*9

2/

61

*0

13

9

VTLD

E0

61

00

00

00

00

5

83

dB

(A) -

40

00

min

-1

EAS00142

LUBRICATING THE DRIVE CHAINThe drive chain consists of many interactingparts. If the drive chain is not maintained pro-perly, it will wear out quickly. Therefore, thedrive chain should be serviced, especiallywhen the motorcycle is used in dusty areas.This motorcycle has a drive chain with smallrubber O-rings between each side plate.Steam cleaning, high-pressure washing, cer-tain solvents, and the use of a coarse brushcan damage these O-rings. Therefore, useonly kerosene to clean the drive chain. Wipethe drive chain dry and thoroughly lubricate itwith engine oil or chain lubricant that is suita-ble for O-ring chains. Do not use any otherlubricants on the drive chain since they maycontain solvents that could damage the O-rings.

EAS00146

CHECKING AND ADJUSTING THE STEERING HEAD1. Stand the motorcycle on a level surface.

ss WARNING


NOTE:

Place the motorcycle on a suitable stand sothat the front wheel is elevated.

2. Check:• steering head

Grasp the bottom of the front fork legs andgently rock the front fork.Binding/looseness Adjust the steeringhead.

3. Remove:• side covers, seat, fuel tank, main switch

protector.Remove handlebar from its position.Remove handle crown.

4. Adjust:• steering head

Recommended lubricantEngine oil or chain lubricant sui-table for O-ring chains

CHKADJCHEEKING AND ADJUSTING THE STEERING HEAD

3-31

a. Remove the lock washer , the upper ringnut , and the rubber washer .

b. Loosen the lower ring nut and then tigh-ten it to specification with a steering nutwrench.

c. Loosen the lower ring nut completely,then tighten it to specification.

ss WARNING

Do not overtighten the lower ring nut.

d. Check the steering head for looseness orbinding by turning the front fork all the wayin both directions. If any binding is felt,remove the lower bracket and check theupper and lower bearings.Refer to “STEERING HEAD” in chapter 4.

e. Install the rubber washer .f. Install the upper ring nut .g. Finger tighten the upper ring nut , then

align the slots of both ring nuts. If neces-sary, hold the lower ring nut and tighten theupper ring nut until their slots are aligned.

h. Install the lock washer .

NOTE:

Make sure the lock washer tabs sit correctly inthe ring nut slots.

5. Install:• Install handle crown• Install Handlebars• Install side covers, seat, fuel tank, main

switch protector.

Steering nut wrench90890-01403

Lower ring nut (initial tighteningtorque)

35 Nm (3.5 m • kg, 24.8 ft • lb)

Lower ring nut (final tightening tor-que)

4 Nm (0.4 m • kg, 2.8 ft • lb)

Nut Cap120 ~ 155 Nm (12.0 ~ 15.5m•kg,85.3 ~ 110.1 ft•lb)

3

12

4

CHKADJ

CHEEKING AND ADJUSTING THE STEERING HEAD/CHECKING THE FRONT FORK

3-32

6. Measure:• steering head tension

NOTE:

Make sure all of the cables and wires are pro-perly routed.

a. Point the front wheel straight ahead.b. Install a plastic locking tie loosely around

the end of the handlebar as shown.c. Hook a spring gauge onto the plastic loc-

king tie.d. Hold the spring gauge at a 90° angle from

the handlebar, pull the spring gauge, andthen record the measurement when thehandlebar starts to run.

e. Repeat the above procedure on the opposi-te handlebar.

f. If the steering head tension is out of speci-fication (both handlebars should be withinspecification), remove the upper bracketand loosen or tighten the upper ring nut.

g. Reinstall the upper bracket and measurethe steering head tension again as descri-bed above.

h. Repeat the above procedure until the stee-ring head tension is within specification.

i. Grasp the bottom of the front fork legs andgently rock the front fork.Binding/looseness Adjust the steeringhead.

EAS00149

CHECKING THE FRONT FORK1. Stand the motorcycle on a level surface.

ss WARNING


Steering head tension200 ~ 250 g

CHKADJ

CHECKING THE FRONT FORK/ADJUSTING THE REARSHOCK ABSORBER ASSEMBLY

3-33

2. Check:• inner tube

Damage/scratches Replace.• oil seal

Oil leakage Replace.3. Hold the motorcycle upright and apply the

front brake.

4. Check:• front fork operation

Push down hard on the handlebar severaltimes and check if the front fork reboundssmoothly.Rough movement Repair.Refer to “FRONT FORK” in chapter 4.

EAS00156

ADJUSTING THE REAR SHOCKABSORBER ASSEMBLY

ss WARNING


Spring preload

CAUTION

Never go beyond the maximum or minimumadjustment positions.

1. Adjust:• loosen the locknut • adjust the spring preload

a. Adjust the spring preload with a ring nutwrench.

b. Turn the adjusting ring in direction a or b .

Ring nut wrench90890-01268

Direction a Spring preload is increa-sed (suspension is harder)

Direction b Spring preload is decrea-sed (suspension is softer).

Adjusting positionsMinimum Standard Maximum220 mm 230 mm 235 mm

(b) (a)

21

CHKADJ

ADJUSTING THE REAR SHOCK ABSORBERASSEMBLY/CHECKING THE TIRES

3-34

2. Tighten:• Tighten the locknut

EAS00164

CHECKING THE TIRESThe following procedure applies to both of thetires.1. Check:• tire pressure

Out of specification Regulate.

ss WARNING

• The tire pressure should only be checkedand regulated when the tire temperatureequals the ambient air temperature.

• The tire pressure and the suspensionmust be adjusted according to the totalweight (including cargo, rider, passengerand accessories) and the anticipatedriding speed.

• Operation of an overloaded motorcyclecould cause tire damage, an accident oran injury.

NEVER OVERLOAD THE MOTORCYCLE.

Tire air pressure (measured on cold tires):DT125RUp to 90 kg (198 lb):

Front:150 kPa (21,8 psi) (1,5 kgf/cm2)

Rear:175 kPa (25,4 psi) (1,75 kgf/cm2)

90 kg (198 lb) to maximum load:Front:

175 kPa (25,4 psi) (1,75 kgf/cm2)Rear:

200 kPa (28,9 psi) (2 kgf/cm2)Maximum load*:

178 kg (392 lb)DT125XUp to 90 kg (198 lb):

Front:180 kPa (26,1 psi) (1,8 kgf/cm2)

Rear:200 kPa (28,9 psi) (2 kgf/cm2)

90 kg (198 lb) to maximum load:Front:

180 kPa (26,1 psi) (1,8 kgf/cm2)Rear:

200 kPa (28,9 psi) (2 kgf/cm2)Maximum load*:

180 kg (396 lb)* Total weight of rider, passenger, cargo and

accessories

CHKADJCHECKING THE TIRES

3-35

ss WARNING

It is dangerous to ride with a worn-out tire.When the tire tread reaches the wear limit,replace the tire immediately.

2. Check:• tire surfaces

Damage/wear Replace the tire.

Tire tread depth Sidewall

ss WARNING

• Do not use a tubeless tire on a wheeldesigned only for tube tires to avoid tirefailure and personal injury from suddendeflation.

• When using tube tires, be sure to installthe correct tube.

• Always replace a new tube tire and a newtube as a set.

• To avoid pinching the tube, make surethe wheel rim band and tube are cente-red in the wheel groove.

• Patching a punctured tube is not recom-mended. If it is absolutely necessary todo so, use great care and replace thetube as soon as possible with a goodquality replacement.

ss WARNING

• After extensive tests, the tires listed belowhave been approved by Yamaha MotorEspaña, S.A. for this model. The front andrear tires should always be by the samemanufacturer and of the same design. Noguarantee concerning handling characteris-tics can be given if a tire combination otherthan one approved by Yamaha is used onthis motorcycle.

Minimum tire tread depth1.6 mm (0.04 in)

1

2

Tube wheel Tube tire onlyTubeless wheel Tube or tubeless tire

CHKADJ

CHECKING THE TIRES/CHECKING AND TIGHTENING THE SPOKES

3-36

ss WARNING

• New tires have a relatively low grip onthe road surface until they have beenslightly worn. Therefore, approximately100 km should be traveled at normalspeed before any high-speed riding isdone.

• After a tire has been repaired or repla-ced, be sure to tighten the tire air valvestem nut and locknut to specifica-tion.

EAS00169

CHECKING AND TIGHTENING THESPOKESThe following procedure applies to all of thespokes.1. Check:• spoke

Bends/damage Replace.Loose Tighten.Tap the spokes with a screwdriver.

NOTE:

A tight spoke will emit a clear, ringing tone; aloose spoke will sound flat.

Tire air valve stem (front wheelonly)

Valve stem lock nut1.5 Nm (0.15 m•kg, 1.1 ft•lb)

Front tire

ManufacturerModel Size

DT125RE MICHELIN T63 80/90-21 48PDT125X PIRELLI Sport Demon 120/70-17 58H

Rear tire

ManufacturerModel Size

DT125RE MICHELIN T63 110/80-18 58PDT125X PIRELLI Sport Demon 140/70-17 66H

1

CHKADJ

CHECKING AND TIGHTENING THE SPOKES/CHECKING AND LUBRICATING THE CABLES

3-37

2. Tighten:• spoke

(with a spoke wrench)

NOTE:

Be sure to tighten the spokes before and afterbreak-in.

EAS00170

CHECKING AND LUBRICATING THECABLESThe following procedure applies to all of theinner and outer cables.

ss WARNING

Damaged outer cable may cause the cableto corrode and interfere with its movement.Replace damaged outer cable and innercables as soon as possible.

1. Check:• outer cable

Damage Replace.2. Check:• cable operation

Rough movement Lubricate.

NOTE:

Hold the cable end upright and pour a fewdrops of lubricant into the cable sheath or usea suitable lubricating device.

2~3.5 Nm (0.2~0.35 m•kg,1.42~2.49 ft•lb)

Recommended lubricantSAE 10W30 Motor Oil

CHKADJ

LUBRICATING THE LEVERS AND PEDALS/LUBRICATING THESIDESTAND/LUBRICANTING THE REAR SUSPENSION

3-38

EAS00171

LUBRICATING THE LEVERS AND PEDALSLubricate the pivoting point and metal-to-metal moving parts of the levers and pedals.

EAS00172

LUBRICATING THE SIDESTANDLubricate the pivoting point and metal-to-metal moving parts of the sidestand.

EAS00174

LUBRICATING THE REAR SUSPENSIONLubricate the pivoting point and metal-to-metal moving parts of the rear suspension.



Recommended lubricantMolybdenum disulfide grease

CHKADJELECTRICAL SYSTEM

3-39

EAS00178

ELECTRICAL SYSTEMCHECKING AND CHARGING THEBATTERY

ss WARNING

Batteries generate explosive hydrogen gasand contain electrolyte which is made ofpoisonous and highly caustic sulfuric acid.Therefore, always follow these preventivemeasures:• Wear protective eye gear when handling

or working near batteries.• Charge batteries in a well-ventilated

area.• Keep batteries away from fire, sparks or

open flames (e.g., welding equipment,lighted cigarettes).

• DO NOT SMOKE when charging or hand-ling batteries.

• KEEP BATTERIES AND ELECTROLYTEOUT OF REACH OF CHILDREN.

• Avoid bodily contact with electrolyte as itcan cause severe burns or permanenteye injury.

FIRST AID IN CASE OF BODILY CONTACT:EXTERNAL• Skin <—> Wash with water.• Eyes <—> Flush with water for 15 minu-

tes and get immediate medical attention.INTERNAL• Drink large quantities of water or milk

followed with milk of magnesia, beatenegg or vegetable oil. Get immediatemedical attention.

CAUTION

• This is a sealed battery. Never removethe sealing caps because the balancebetween cells will not be maintained andbattery performance will deteriorate.

• Charging time, charging amperage andcharging voltage for an MF battery aredifferent from those of conventional bat-teries. The MF battery should be chargedas explained in the charging methodillustrations. If the battery is overchar-ged, the electrolyte level will drop consi-derably. Therefore, take special carewhen charging the battery.

CHKADJCHECKING AND CHARGING THE BATTERY

3-40

NOTE:

Since MF batteries are sealed, it is not possi-ble to check the charge state of the battery bymeasuring the specific gravity of the electroly-te. Therefore, the charge of the battery has tobe checked by measuring the voltage at thebattery terminals.

1. Remove:• Rear side cover (right)• Battery cover

2. Disconnect:• battery leads

(from the battery terminals)

CAUTION

First, disconnect the negative battery lead, and then the positive battery lead .

3. Remove:• battery

4. Check:• battery charge

a. Connect a pocket tester to the battery ter-minals.

NOTE:

• The charge state of an MF battery can bechecked by measuring its open-circuit vol-tage (i.e., the voltage when the positive bat-tery terminal is disconnected).

• No charging is necessary when the open-circuit voltage equals or exceeds 12.8 V.

b. Check the charge of the battery, as shownin the charts and the following example.

Examplec. Open-circuit voltage = 12.0 Vd. Charging time = 6.5 hourse. Charge of the battery = 20 ~ 30%

5. Charge:• battery

Positive tester probe positive batteryterminal.

Negative tester probe negative batteryterminal.

1 2

CHKADJCHECKING AND CHARGING THE BATTERY

3-41

ss WARNING

Do not quick charge a battery.

CAUTION

• Never remove the MF battery sealingcaps.

• Do not use a high-rate battery chargersince it forces a high-amperage currentinto the battery quickly and can causebattery overheating and battery platedamage.

• If it is impossible to regulate the char-ging current on the battery charger, becareful not to overcharge the battery.

• When charging a battery, be sure toremove it from the motorcycle. (If char-ging has to be done with the batterymounted on the motorcycle, disconnectthe negative battery lead from the bat-tery terminal.)

• To reduce the chance of sparks, do notplug in the battery charger until the bat-tery charger leads are connected to thebattery.

• Before removing the battery charger leadclips from the battery terminals, be sureto turn off the battery charger.

• Make sure the battery charger lead clipsare in full contact with the battery termi-nal and that they are not shorted. Acorroded battery charger lead clip maygenerate heat in the contact area and aweak clip spring may cause sparks.

• If the battery becomes hot to the touchat any time during the charging process,disconnect the battery charger and letthe battery cool before reconnecting it.Hot batteries can explode!

• As shown in the following illustration, theopen-circuit voltage of an MF batterystabilizes about 30 minutes after char-ging has been completed. Therefore,wait 30 minutes after charging is com-pleted before measuring the open-circuitvoltage.

Charging method using a variable-current(voltage) chargerCharging method using a constant voltagecharger6. Install:• battery

7. Connect:• battery leads

(to the battery terminals)

CHKADJ

CHECKING AND CHARGING THE BATTERY/CHECKING THE FUSES

3-42

CAUTION

First, connect the positive battery lead ,and then the negative battery lead .

8. Check:• battery terminals

Dirt Clean with a wire brush.Loose connection Connect properly.

9. Lubricate:• battery terminals

10. Install:• Battery cover• Rear side cover (right)

EAS00181

CHECKING THE FUSESThe following procedure applies to all of thefuses.

CAUTION

To avoid a short circuit, always set the mainswitch to “OFF” when checking or repla-cing a fuse.

1. Remove:• Rear side cover (right)

2. Check:• fuse

a. Connect the pocket tester to the fuse andcheck the continuity.

NOTE:

Set the pocket tester selector to “<OHM><MLT> 1”.

b. If the pocket tester indicates “<INF>”,replace the fuse.

Recommended lubricantDielectric grease

Pocket tester90890-03112

1 2

CHKADJ

CHECKING THE FUSES/REPLACING THE HEADLIGHT BULB

3-43

3. Replace:• blown fuse

a. Set the main switch to “OFF”.b. Install a new fuse of the correct amperage

rating.c. Set on the switches to verify if the electrical

circuit is operational.d. If the fuse immediately blows again, check

the electrical circuit.

ss WARNING

Never use a fuse with an amperage ratingother than that specified. Improvising orusing a fuse with the wrong amperagerating may cause extensive damage to theelectrical system, cause the lighting andignition systems to malfunction and couldpossibly cause a fire.

4. Install:• Rear side cover (right).

EAS00182

REPLACING THE HEADLIGHT BULB1. Remove front cowling2. Disconnect:• Couplers

3. Remove headlight bulb cover 4. Remove the headlight bulb holder accor-

ding to the drawing, then remove the defec-tive bulb

ss WARNING

Since the headlight bulb gets extremely hot,keep flammable products and your handsaway from the bulb until it has cooleddown.

Fuses Amperage rating Q'tyMain 15A 1

Reserve 15A 1

2

1

2

1

CHKADJ

REPLACING THE HEADLIGHT BULB/ADJUSTING THE HEADLIGHT BEAM

3-44

5. Install:• headlight bulbNew

Secure the new headlight bulb with theheadlight bulb holder.

CAUTION

Avoid touching the glass part of the head-light bulb to keep it free from oil, otherwisethe transparency of the glass, the life of thebulb and the luminous flux will be adverselyaffected. If the headlight bulb gets soiled,thoroughly clean it with a cloth moistenedwith alcohol or lacquer thinner.

6. Install:• headlight bulb holder

7. Install:• headlight bulb cover

8. Connect:• Front cowling

EAS00184

ADJUSTING THE HEADLIGHT BEAM1. Adjust:• headlight beam (vertically)

a. Loosen screws and b. Adjust the headlight verticallyc. Tighten screw and

2

1

CHAS

4

CHAPTER 4CHASSIS

FRONT WHEEL …………………………………………………………………4-1REMOVAL ………………………………………………………………………4-2INSPECTION……………………………………………………………………4-3INSTALLATION …………………………………………………………………4-5

REAR WHEEL ……………………………………………………………………4-7REMOVAL ………………………………………………………………………4-8INSPECTION……………………………………………………………………4-9INSTALLATION …………………………………………………………………4-9

FRONT AND REAR BRAKE …………………………………………………4-11BRAKE PAD REPLACEMENT ………………………………………………4-13CALIPER DISASSEMBLY ……………………………………………………4-18MASTER CYLINDER DISASSEMBLY………………………………………4-19INSPECTION AND REPAIR …………………………………………………4-23ASSEMBLY ……………………………………………………………………4-27AIR BLEEDING ………………………………………………………………4-35

FRONT FORK ……………………………………………………………………4-37REMOVAL ……………………………………………………………………4-38DISASSEMBLY ………………………………………………………………4-38INSPECTION …………………………………………………………………4-40ASSEMBLY ……………………………………………………………………4-41

STEERING HEAD AND HANDLEBAR ………………………………………4-45REMOVAL ……………………………………………………………………4-46INSPECTION …………………………………………………………………4-49INSTALLATION ………………………………………………………………4-50

REAR SHOCK ABSORBER AND SWINGARM ……………………………4-55HANDLING NOTES …………………………………………………………4-57NOTES ON DISPOSAL ………………………………………………………4-57REMOVAL ……………………………………………………………………4-57INSPECTION …………………………………………………………………4-62SIDE CLEARANCE ADJUSTMENT…………………………………………4-62INSTALLATION ………………………………………………………………4-64

DRIVE CHAIN AND SPROCKETS ……………………………………………4-66REMOVAL ……………………………………………………………………4-67INSPECTION …………………………………………………………………4-68INSTALLATION ………………………………………………………………4-70

CHAS

CHASFRONT WHEEL

4-1

CHASSISFRONT WHEEL

Hub Bearing Collar Oil Seal Rim Spoke

Cap Collar Dust cover10 Wheel axle11 Cap12 Gear unit (speedometer)

58 Nm (5,8 m • kg, 42ft•lb)

DT125RE

A Tire Size:80/90-21 48P

B Rim Size:21x1.60

C Rim Runout Limit:Vertical:

1,0 mm (0,08 in)Lateral:

0,5 mm (0,02 in)

Basic weight: DT125RE DT125XWith oil and full fuel tank 126 kg 134 kg

Maximum load* 178 kg (392 lb) 180 kg (396 lb)

Cold tire pressure

Up to 90 Kg (198 bf) load* 150kPa 180Kpa(1,5kgf/cm2)(21,8psi) (1,8kgf/cm2)(26,1psi)

90kg (198lbf)~Maximum load 175kPa 180Kpa(1,75kgf/cm2)(25,4psi) (1,8kgf/cm2)(26,1psi)

Off-road riding 150kPa —(1,5kgf/cm2)(21,8psi)

DT125X

A Tire Size:120/70/17 58H

B Rim Size:17x3.00



0,5 mm (0,02 in)

CHASREMOVING THE FRONT WHEEL

4-2

EAS00519

REMOVING THE FRONT WHEEL

1. Stand the motorcycle on a level surface.

ss WARNING


NOTE:

Place the motorcycle on a suitable stand sothat the front wheel is elevated.

2. Remove:• Cable holder (speedometer)

3. Disconnect: • Speedometer cable

4. Loosen: • Nuts (Axle holder)

5. Remove:• Front wheel axle• Front wheel • Gear unit (speedometer) • Spacer collar

NOTE:

Do not apply the brake lever when removingthe brake caliper.

2

1

3

2

1 3

CHASCHECKING THE FRONT WHEEL

4-3

EAS00526

CHECKING THE FRONT WHEEL1. Check:• wheel axle

Roll the wheel axle on a flat surface.Bends Replace.

ss WARNING

Do not attempt to straighten a bent wheelaxle.

2. Check:• tire• front wheel

Damage/wear Replace.Refer to “CHECKING THE TIRES” and“CHECKING THE WHEELS” in chapter 3.

3. Check:• spokes

Bends/damage Replace.Loose Tighten.Tap the spokes with a screwdriver.

NOTE:

A tight spoke will emit a clear, ringing tone, aloose spoke will sound flat.

4. Tighten:• spokes

NOTE:

After tightening the spokes, measure the frontwheel runout.

5. Measure:• front wheel radial runout• front wheel lateral runout

Over the specified limits Replace.

Front wheel radial runout limit1 mm (0.04 in)

Front wheel lateral runout limit0.5 mm (0.02 in)

2~3.5 Nm (0.2~0.35 m•kg,1.42~2.49 ft•lb)

1

Tire air valve stem locknut1.5 Nm (0.15 m•kg, 1.1 ft•lb)

CHASCHECKING THE FRONT WHEEL

4-4

6. Check:• collars

Damage/wear Replace.

ss WARNING

• After mounting a new tire, ride conserva-tively for a while to become accustomedto the “feel” of the new tire and to allowthe tire to seat itself properly in the rim.Failure to do so could lead to an accidentwith possible injury to the rider or dama-ge to the motorcycle.

• After a tire has been repaired or repla-ced, be sure to tighten the tire air valvestem locknut to specification.

7. Check:• wheel bearings

Front wheel turns roughly or is loose

Replace the wheel bearings.• oil seals


8. Replace:• wheel bearings • oil seals

a. Clean the outside of the front wheel hub.b. Remove the oil seals with a flat-head

screwdriver.

NOTE:

To prevent damaging the wheel, place a ragbetween the screwdriver and the wheel surfa-ce.

c. Remove the wheel bearings with a generalbearing puller.

d. Install the new wheel bearings and oil sealsin the reverse order of disassembly.

NewNew

CHASCHECKING THE FRONT WHEEL/INSTALLING THE FRONT WHEEL

4-5

CAUTION

Do not contact the wheel bearing inner raceor balls. Contact should be made only withthe outer race.

NOTE:

Use a socket that matches the diameter ofthe wheel bearing outer race and oil seal.

EAS00542

INSTALLING THE FRONT WHEEL1. Lubricate:• wheel axle• wheel bearings• oil seal lips• speedometer drive gear• speedometer driven gear

2. Install:• speedometer gear unit

NOTE:

Make sure the speedometer gear unit and thewheel hub are installed with the two projec-tions meshed into the two slots respectively.

3. Install:• front wheel

NOTE:

Make sure the slot in the speedometer gearunit fits over the stopper on the outer tube.

Recommended lubricantLithium-soap-based grease

1

7

1

CHASINSTALLING THE FRONT WHEEL

4-6

4. Tighten:• wheel axle

• Nut (Axle holder):

ss WARNING

Make sure the brake cable is routed pro-perly.

CAUTION

Before tightening the wheel axle nut, pushdown hard on the handlebar several timesand check if the front fork rebounds smo-othly.

45~70 Nm (4.5~7.0 m•kg, 33~51.3 ft•lb)

7.5~12 Nm (0.75~1.2 m•kg,5.5~8.8 ft•lb)

CHASREAR WHEEL

4-7

REAR WHEEL

Hub Collar Bearing Oil Seal Rim Spoke Cap

Driven Sprocket Bolt10 Nut11 Collar12 Dust Cover13 Collar14 Oil Seal

15 Chain puller16 Chain puller17 Wheel axle18 Washer19 Nut20 Drive chain

90 Nm (9,0 m • kg,65ft•lb)

DT125RE

A Tire Size:110/80-18 58P

B Rim Size:18 x 1,85

C Rim Runout:Vertical:


0,5 mm (0,02 in)

Basic weight: DT125RE DT125XWith oil and full fuel tank 126 kg 134 kg

Maximum load* 178 kg (392 lb) 180 kg (396 lb)

Cold tire pressure

Up to 90 Kg (198 bf) load* 175kPa 200Kpa(1,75kgf/cm2)(25,4psi) (2,0kgf/cm2)(28,9psi)

90kg (198lbf)~Maximum load 200kPa 200Kpa(2,0kgf/cm2)(28,9psi) (2,0kgf/cm2)(28,9psi)

Off-road riding 175kPa —(1,75kgf/cm2)(25,4psi)

DT125X

A Tire Size:140/70-17 66H

B Rim Size:17x3.50



0,5 mm (0,02 in)

CHASREMOVING THE REAR WHEEL

4-8

EAS00561

REMOVING THE REAR WHEEL1. Stand the motorcycle on a level surface.

ss WARNING


NOTE:

Place the motorcycle on a suitable stand sothat the rear wheel is elevated.

2. Remove:• rear brake caliper protection

NOTE:

Do not depress the brake pedal when remo-ving the brake caliper.

3. Loosen:• bolts (swingarm end).

4. Remove:• wheel axle nut • wheel axle• rear wheel

NOTE:

Push the rear wheel forward and remove thedrive chain from the rear wheel sprocket.

1

2

1

1

CHASINSPECTING THE REAR WHEEL/

INSTALLING THE REAR WHEEL

4-9

INSPECTING THE REAR WHEEL1. Inspect:• Rear wheel axle

Refer to the “FRONT WHEEL - INSPEC-TION” section.

2. Inspect:• Wheel hub • Dust covers (Bearings) • Wheel


3. Measure:• Wheel runout


4. Check:• Wheel bearings


5. Check:• Wheel balance


EAS00572

INSTALLING THE REAR WHEELWhen installing the rear wheel, reverse theremoval procedure. Note the following points:1. Lubricate:• wheel axle • wheel bearings• oil seal lips

2 4

13

2

4

3 2

2 3

1

CHASINSTALLING THE REAR WHEEL

4-10

2. Adjust:• Drive chain slack a

• Refer to the “DRIVE CHAIN SLACKADJUSTMENT” section in CHAPTER 3.

3. Tighten:• wheel axle nut • bolts (swingarm end)

Drive chain slack:DT125RE 40~55mm (1,77~2,16in.)DT125X 25~40mm (0,98~1,58 in.)


80~100Nm (8.0~10.0 m•kg,58.7~73.3 ft•lb)

30 Nm (3 m•kg, 22 ft•lb)

1

CHASFRONT AND REAR BRAKE

4-11

FRONT AND REAR BRAKE

Master cylinder cap Diaphragm Master cylinder kit Master cylinder

Brake hose Brake caliper Pad spring Piston

Piston seal10 Dust seal11 Brake pad12 Brake disc

26 Nm (2,6 m • kg, 19ft•lb)

D USE NEW ONE

6 Nm (0,6 m • kg,4,3ft•lb)

18 Nm (1,8 m • kg, 13ft•lb)

D USE NEW ONE

20 Nm (2,0m•kg,14ft•lb)

35 Nm (3,5 m • kg, 25ft•lb)

D USE NEW ONE

A Brake Fluid Type:DOT 4 or DOT 3

B Brake pad Wear Limit:0,8 m (0.03 in.)

C Brake Disc Wear Limit:3mm (0.12 in.)

CHASFRONT AND REAR BRAKE

4-12

Reservoir tank cap protec-tor

Reservoir tank cap Inner cap Diaphragm Reservoir tank Reservoir hose

Master cylinder Master cylinder kit Brake hose10 Brake caliper11 Piston12 Piston seal

13 Dust seal14 Shim15 Pad spring16 Brake pads17 Brake disc

A Brake Fluid Type:DOT 4 or DOT 3

B Brake pad Wear Limit:0,8 m (0.03 in.)

C Brake Disc Wear Limit:4mm (0.16 in.)

18 Nm (1,8 m • kg, 13ft•lb)

D USE NEW ONE6 Nm (0,6 m • kg,4,3ft•lb)

D USE NEW ONE26 Nm (2,6 m • kg,19ft•lb)

10 Nm (1,0 m • kg, 7,2ft•lb)

4 Nm (0,4 m • kg,2,9ft•lb)

D USE NEW ONE

CHASREPLACING THE FRONT BRAKE PADS

4-13

EAS00579

CAUTION

Disc brake components rarely requiredisassembly.Therefore, always follow these preventivemeasures:• Never disassemble brake components

unless absolutely necessary.• If any connection on the hydraulic brake

system is disconnected, the entire brakesystem must be disassembled, drained,cleaned, properly filled, and bled afterreassembly.

• Never use solvents on internal brakecomponents.

• Use only clean or new brake fluid for cle-aning brake components.

• Brake fluid may damage painted surfa-ces and plastic parts. Therefore, alwaysclean up any spilt brake fluid immedia-tely.

• Avoid brake fluid coming into contactwith the eyes as it can cause seriousinjury.

FIRST AID FOR BRAKE FLUID ENTERINGTHE EYES:• Flush with water for 15 minutes and get

immediate medical attention.

EAS00581

REPLACING THE FRONT BRAKE PADS

NOTE:

When replacing the brake pads, it is notnecessary to disconnect the brake hose ordisassemble the brake caliper.

1. Loosen:• retaining bolt (caliper body)

2. Turn:• brake caliper counterclockwise

2

2

1

CHASREPLACING THE FRONT BRAKE PADS

4-14

3. Remove:• brake pads • brake pad springs

4. Measure:• brake pad wear limit a

Out of specification Replace the brakepads as a set.

5. Install:• brake pad springs • brake pads

NOTE:

Always install new brake pads and a newbrake pad spring as a set.

a. Connect a clear plastic hose tightly tothe bleed screw . Put the other end of thehose into an open container.

b. Loosen the bleed screw and push the brakecaliper pistons into the brake caliper withyour finger.

c. Tighten the bleed screw.

d. Install new brake pads and a new brake padspring.

Brake pad wear limit0.8 mm (0.03 in)

Bleed screw6 Nm (0.6 m•kg, 4.3 ft•lb)

1

1

2

CHASREPLACING THE FRONT BRAKE PADS/

REPLACING THE REAR BRAKE PADS

4-15

6. Lubricate:• retaining bolt

CAUTION

• Do not allow grease to contact the brakepads.

• Remove any excess grease.

7. Install:• retaining bolt


Below the minimum level mark a Addthe recommended brake fluid to the properlevel.Refer to “CHECKING THE BRAKE FLUIDLEVEL” in chapter 3.

9. Check:• brake lever operation

Soft or spongy feeling Bleed the brakesystem.Refer to “BLEEDING THE HYDRAULICBRAKE SYSTEM” in chapter 3.

EAS00583

REPLACING THE REAR BRAKE PADS

NOTE:

When replacing the brake pads, it is notnecessary to disconnect the brake hose ordisassemble the brake caliper.


18 Nm (1,8 m•kg, 13ft•lb)

FRONT

a

1

CHASREPLACING THE REAR BRAKE PADS

4-16

1. Remove:• Protector (caliper body) • Retaining bolt • Turn the caliper body counterclockwise

2. Remove:• brake pads • brake pad springs • Shim (brake pad)

3. Measure:• brake pad wear limit a

Out of specification Replace the brakepads as a set.

4. Install:• brake pad shims

(onto the brake pads)• brake pad springs• brake pads

NOTE:

Always install new brake pads, brake padshims, and a brake pad spring as a set.

a. Connect a clear plastic hose tightly tothe bleed screw . Put the other end of thehose into an open container.

b. Loosen the bleed screw and push the brakecaliper pistons into the brake caliper withyour finger.

c. Tighten the bleed screw.



2

1

1

2

CHASREPLACING THE REAR BRAKE PADS

4-17

5. Lubricate:• Retaining bolt (Caliper body)

6. Tighten:• Retaining bolt (Caliper body)

7. Check:• brake fluid levelBelow the minimum level mark Addthe recommended brake fluid to the properlevel.Refer to “CHECKING THE BRAKE FLUIDLEVEL” in chapter 3.

8. Check:• brake pedal operation

Soft or spongy feeling Bleed the brakesystem.Refer to “BLEEDING THE HYDRAULICBRAKE SYSTEM” in chapter 3.

18 Nm (1,8 m•kg, 13ft•lb)

1

1

CHASDISASSEMBLING THE FRONT BRAKE CALIPER

4-18

EAS00618

DISASSEMBLING THE FRONT BRAKECALIPER

NOTE:

Before disassembling the brake caliper, drainthe brake fluid from the entire brake system.

1. Remove:• union bolt • copper washers • brake hose

NOTE:

Put the end of the brake hose into a containerand pump out the brake fluid carefully.

2. Remove:• Retaining bolt (caliper body) • Brake pads • Pad springs

Refer to the “BRAKE PAD REPLACE-MENT” section.

3. Remove:• Caliper body • Caliper bracket

4. Remove:• Caliper piston • Clip• Dust seal• Piston seal

2 1

2

1

2

1

2

CHASDISASSEMBLING THE FRONT BRAKE CALIPER/

DISASSEMBLING THE REAR BRAKE CALIPER

4-19

a Blow compressed air into the brake hosejoint opening a to force out the piston fromthe brake caliper.

ss WARNING

• Cover the brake caliper piston with a rag.Be careful not to get injured when thepiston is expelled from the brake caliper.

• Never try to pry out the brake caliper pis-ton.

b. Remove the clip using a thin screwdriver

CAUTION

• When removing the clip, take care not todamage the dust seal and caliper body.

c. Remove the brake caliper piston seals.

EAS00626

DISASSEMBLING THE REAR BRAKECALIPER

NOTE:

Before disassembling the brake caliper, drainthe brake fluid from the entire brake system.

1. Remove:• Protector (Caliper body) • Union bolts • Copper washers• Retaining bolt (Caliper body)

NOTE:

Put the end of the brake hose into a containerand pump out the brake fluid carefully.

2. Remove:• Brake pads • Shim (brake pads) • Pad springs


4

1 23

3

1 2

(a)

CHASDISASSEMBLING THE REAR BRAKE CALIPER

4-20

3. Disconnect the dust boot and then pullout the caliper body from the guide shaft on te caliper bracket .

4. Remove:• Rear wheel

Refer to the “REAR WHEEL” section.• Caliper bracket

5. Remove:• Caliper piston • Dust seal • Piston seal

a. Blow compressed air into the brake hosejoint opening a to force out the piston fromthe brake caliper.

ss WARNING

• Cover the brake caliper piston with a rag.Be careful not to get injured when thepiston is expelled from the brake caliper.

• Never try to pry out the brake caliper pis-ton.

b. Remove the brake caliper piston seals.

3

12

(a)

CHASDISASSEMBLING THE FRONT BRAKE MASTER

CYLINDER

4-21

EAS00588

DISASSEMBLING THE FRONT BRAKEMASTER CYLINDER

NOTE:

Before disassembling the front brake mastercylinder, drain the brake fluid from the entirebrake system.

1. Remove:• Brake switch • Brake lever • Return spring (brake lever)

NOTE:

When removing the brake switch push theswitch hook using a suitable rod, then pull itout.

2. Pull back the brake hose cover from themaster cylinder.

3. Remove:• Union bolt • Cooper washers

4. Remove:• Bracket (master cylinder)• Master cylinder

23

1

23

1

CHASDISASSEMBLING THE FRONT BRAKE MASTER

CYLINDER/DISASSEMBLING THE REAR BRAKE MASTERCYLINDER

4-22

5. Remove:• Cap (master cylinder) • Diaphragm• Dust boot• Circlip• Master cylinder kit

NOTE:

To collect any remaining brake fluid, place acontainer under the master cylinder and theend of the brake hose.

DISASSEMBLING THE REAR BRAKEMASTER CYLINDER1. Remove:• Brake hose guides

2. Loosen:• Union bolt

3. Remove:• Cotter pin • Washer • Cotter pin • Screw (Reservoir tank • Bolts (master cylinder) • Master cylinder

(with brake hose and reservoir tank)

1

8

7

7

6

1

CHASDISASSEMBLING THE REAR BRAKE MASTER

CYLINDER/CHECKING THE FRONT AND REAR BRAKECALIPER

4-23

4. Remove:• Brake hoses • Reservoir tank • Circlip • Push rod• Master cylinder kit

5. Remove:• Cap (reservoir tank) • Inner cap (reservoir tank) • Diaphragm

NOTE:

To collect any remaining brake fluid, place acontainer under the master cylinder and theend of the brake hose.

EAS00630

CHECKING THE FRONT AND REAR BRAKECALIPER

Recommended brake component replacement schedule

Brake pads If necessaryPiston seals Every two yearsBrake hose Every four yearsBrake fluid Every two years and

whenever the brake isdisassembled

1

35

2

CHASCHECKING THE FRONT AND REAR BRAKE CALIPER

4-24

1. Check:• brake caliper piston

Rust/scratches/wear Replace thebrake caliper piston.

• brake caliper cylinder Scratches/wear Replace the brakecaliper assembly.

• brake caliper body Cracks/damage Replace the brakecaliper assembly.

• brake fluid delivery passage(brake caliper body)Obstruction Blow out with compressedair.

ss WARNING

Whenever a brake caliper is disassembled,replace the piston seals.

2. Check:• Caliper body • Caliper bracket

Cracks/damage Replace.• Oil delivery passage (caliper body)

Blow out with compressed air.• Slide collar (caliper body) • Guide shaft (caliper bracket)

Rust/wear/damage Replace.• Slider boot caliper body) • Dust boot (Guide pin - bracket)

Cracks/damage Replace.A FrontB Rear

B

A


4-25

3. Check:• Master cylinder

Wear/scratches Replace the caliperassembly.

• Master cylinder body Cracks/damage Replace.

• Oil delivery passage (caliper body)Blow out with compressed air.A FrontB Rear

4. Check:• Master cylinder kit Scratches/Wear/Damage Replace.

A FrontB Rear

5. Check:• Reservoir tank

Cracks/damage Replace.• Diaphragm (Front) Wear/damage Replace.

6. Check:• Brake hoses

Cracks/wear/damage Replace.

7. Measure:• Brake pads (thickness) a

Out of specification Replace.

Wear indicator


1 1

2

1


4-26

NOTE:

• Replace the pad spring as a set if padreplacement is required.

• Replace the pads as a set if either if foundto be worn to the wear limit.

8. Inspect:• Brake disc

Galling/damage Replace.

9. Measure:• Brake disc deflection

Out of specification Inspect wheelrunout. If wheel runout is in good condition, repla-ce.

• Brake disc thickness Out of specification Replace.

Dial gaugeA FrontB Rear

Maximum deflection:0.15mm (0.006in.)

Minimum thickness:Front: 3.0mm (0.12in.)Rear: 4.0mm (0.16in.)

Bolt (brake disc):20 Nm (2.0 m•kg, 14ft•lb)Use LOCTITE®

1

CHASASSEMBLING AND INSTALLING THE FRONT AND

REAR BRAKE CALIPER

4-27

ASSEMBLING AND INSTALLING THEFRONT AND REAR BRAKE CALIPER

ss WARNING

• Before installation, all internal brakecomponents should be cleaned andlubricated with clean or new brake fluid.

• Never use solvents on internal brakecomponents as they will cause the pis-ton seals to swell and distort.

• Whenever a brake caliper is disassem-bled, replace the brake caliper pistonseals.

Front brake1. Install:• Master cylinder kit • Circlip • Dust boot

2. Install:• Master cylinder

NOTE:

• Install the master cylinder bracket with the“UP” mark facing upward.

• Tighten first the upper bolt, then the lowerbolt.

3. Install:• Return spring (brake lever) • Brake lever • Brake switch

NOTE:

Apply lithium soap base grease to the brakelever pivot.

FRONT

23

1

1

2 3 1

Recommended brake fluidDOT 4

Bolts (Master cylinder bracket):9 Nm (0.9 m•kg, 6.5ft•lb)


REAR BRAKE CALIPER

4-28

4. Install:• Piston seal • Dust seal • Clip • Caliper piston

ss WARNING

Always use new piston seal and dust seal.

CAUTION

Install the clip into the slot on the caliperbody correctly.

5. Install:• Caliper bracket

6. Install:• Pad springs• Brake pads


7. Install:• Caliper body

NOTE:

Apply the lithium soap-base grease onto thecaliper guide shaft and retaining bolt.

CAUTION

• Take care no to allow the brake pads tobe smeared by grease.

• Wipe off any unnecessary grease thatcomes out of place.

Caliper bracket:35 Nm (3.5 m•kg, 25ft•lb)

Retaining bolt (Caliper body):18 Nm (1.8m•kg, 13ft•lb)

1

2


REAR BRAKE CALIPER

4-29

8. Install:• Copper washers • Brake hose • Union bolt

CAUTION

When installing the brake hoses to the cali-per and master cylinder lightly touchthe brake pipe with the projections onthem.

ss WARNING

• Proper hose routing is essential to insu-re safe machine operation. Refer to“CABLE ROUTING”

• Always use new copper washers.

9. Fill:• Master cylinder tank

CAUTION


ss WARNING



• When refilling, be careful that water doesnot enter the brake master cylinderreservoir. Water will significantly lowerthe boiling point of the brake fluid andcould cause vapor lock.

Union bolt:26 Nm (2.6m•kg, 19ft•lb)

Recommended brake fluid:DOT 4

2

3

1

3


REAR BRAKE CALIPER

4-30

10. Bleed:• brake system

Refer to “AIR BLEEDING” section.11. Check:• brake fluid level

Below the minimum level mark a Addthe recommended brake fluid to the properlevel.Refer to “BRAKE FLUID INSPECTION” inchapter 3.

”Lower” level line.

12. Install:• Diaphragm • Cap (Master cylinder)

13. Adjust:• Front brake lever free play

Refer to the “FRONT BRAKE ADJUST-MENT” section in chapter 3.

Screw (Master cylinder):2 Nm (0.2m•kg, 1.4ft•lb)

Free play:2~5mm (0.08~0.20in)

12

(a)

2

1

3


REAR BRAKE CALIPER

4-31

ASSEMBLING AND INSTALLING THEFRONT AND REAR BRAKE CALIPER1. Install:• Master cylinder kit • Push rod • Circlip • Dust boot • Brake hoses • Cooper washers • Union bolt • Reservoir tank

NOTE:

At this time, teporarily tighten the union bolt

ss WARNING

Always use a new cooper washer

2. Install:• Master cylinder • Reservoir tank • Pin • Washer • Cotter pin • Brake hose guides

NOTE:

Apply the lithium-soap base grease to the pin.

ss WARNING

Always use a new cotter pin.

3. Install:• Piston seal • Dust seal • Caliper piston

ss WARNING

Always use new piston seal and dust seal

Bolt (Master cylinder):10 Nm (1.0 m•kg, 7.2 ft•lb)

Screw (Reservoir tank):4 Nm (0.4 m•kg, 2.9 ft•lb)

8

7

6

5

1

234

2

166


REAR BRAKE CALIPER

4-32

NOTE:

When installing the caliper piston , be sure tohave it’s open end facing the caliper cylinder

4. Install:• Caliper bracket • Rear wheel

Refer to the “REAR WHEEL INSTALLA-TION” section.

NOTE:

Be sure the boss on the swingarm correctlyengages with the locating slot on the caliperbracket.

5. Install:• Pad springs • Brake pads • Shim


6. Install:• Caliper body

NOTE:

Apply the lithium-soap base grease onto thecaliper guide shaft and retaining bolt

CAUTION

• Take care not to allow the brake pads tobe smeared by grease.

• Wipe off any unnecessary grease thatcomes out of place.

Retaining Bolt (Caliper body):18 Nm (1.8 m•kg, 13 ft•lb)

1

1

1 2 3


REAR BRAKE CALIPER

4-33

7. Install:• Cooper washers • Brake hose • Union bolt • Protector (Caliper body)

CAUTION

When installing the brake hoses to the cali-per and master cylinder , lightly touchthe brake pipe with the projections onthem.

ss WARNING

• Proper hose routing is essential to insu-re safe machine operation. Refer to“CABLE ROUTING” section.

• Always use new cooper washers.

CAUTION


ss WARNING



• When refilling, be careful that water doesnot enter the brake master cylinderreservoir. Water will significantly lowerthe boiling point of the brake fluid andcould cause vapor lock.

Union Bolt:26 Nm (2.6 m•kg, 19 ft•lb)

Recommended brake fluid:DOT 4If DOT 4 is not avaliable DOT 3can be used.

4

3

1

2


REAR BRAKE CALIPER

4-34

9. Bleed:• brake system

Refer to “AIR BLEEDING” section.


Below the minimum level mark Addthe recommended brake fluid to the properlevel.Refer to “BRAKE FLUID INSPECTION” inchapter 3.

”Lower” level line.

11. Install:• Diaphragm • Inner cap (Reservoir tank) • Cap (Master cylinder)

12. Adjust:• Rear brake pedal height (a)

Refer to the “REAR BRAKE ADJUST-MENT” section.

13. Adjust:• Drive chain slack (a)

Refer to the “DRIVE CHAIN SLACKADJUSTMENT” section in chapter 3.

Pedal height:15mm (0.95in)Below top of footrest.

Drive chain slack:DT125RE 40~55mm (1,77~2,16in.)DT125X 25~40mm (0,98~1,58 in.)

REAR

1

1

CHASBLEEDING THE HYDRAULIC BRAKE SYSTEM

4-35

EAS00134

BLEEDING THE HYDRAULIC BRAKE SYSTEM

ss WARNING

Bleed the hydraulic brake system whene-ver:• the system is disassembled.• a brake hose is loosened, disconnected

or replaced.• the brake fluid level is very low.• brake operation is faulty.

NOTE:

• Be careful not to spill any brake fluid orallow the brake master cylinder reservoir orbrake fluid reservoir to overflow.

• When bleeding the hydraulic brake system,make sure there is always enough brakefluid before applying the brake. Ignoring thisprecaution could allow air to enter thehydraulic brake system, considerably lengt-hening the bleeding procedure.

• If bleeding is difficult, it may be necessaryto let the brake fluid settle for a few hours.Repeat the bleeding procedure when thetiny bubbles in the hose have disappeared.

1. Bleed:• hydraulic brake system

a. Fill the brake fluid reservoir to the properlevel with the recommended brake fluid.

b. Install the diaphragm (brake master cylinderreservoir or brake fluid reservoir).

c. Connect a clear plastic hose tightly to thebleed screw .

A FrontB Rear

d. Place the other end of the hose into a con-tainer.

e. Slowly apply the brake several times.f. Fully pull the brake lever or fully press down

the brake pedal and hold it in position.g. Loosen the bleed screw.

1

2

A

B

CHASBLEEDING THE HYDRAULIC BRAKE SYSTEM

4-36

NOTE:

Loosening the bleed screw will release thepressure and cause the brake lever to contactthe throttle grip or the brake pedal to fullyextend.

h. Tighten the bleed screw and then releasethe brake lever or brake pedal.

i. Repeat steps (e) to (h) until all of the air bub-bles have disappeared from the brake fluid inthe plastic hose.

j. Tighten the bleed screw to specification.

k. Fill the brake fluid reservoir to the properlevel with the recommended brake fluid.Refer to “CHECKING THE BRAKE FLUIDLEVEL”.

ss WARNING

After bleeding the hydraulic brake system,check the brake operation.


CHASFRONT FORKS

4-37

FRONT FORKS

Cap bolt O-ring Spacer Spring seat Fork spring Inner fork tube

Damper rod Oil lock pieces Circlip10 Dust seal11 Oil seal

12 Washer13 Slide bush14 Outer fork tube15 Axle holder16 Fork boot

C USE NEW ONE

23 Nm (2,3m•kg,17ft•lb)

30 Nm (3,0 m • kg, 22ft•lb)

A FOR OIL (EACH):CAPACITY:

495 cm3

GRADE:FOR OIL 10W OR EQUIVALENT

OIL LEVEL:165.5mm

Below the top of inner tubefully rebounded withoutfork spring

62 Nm (6,2 m • kg, 45ft•lb)

10 Nm (1,0 m • kg, 7,2ft•lb)

LT

B FOR SPRING:MINIMUM FREELENGTH:

503mm

C USE NEW ONE

CHASREMOVAL/DISASSEMBLY

4-38

REMOVAL

ss WARNING

Support the motorcycle securely so there isno danger of it falling over.

1 Elevate the front wheel by placing a suitablestand under the engine.

2. Remove:• Brake caliper assembly

3. Loosen:• upper bracket pinch bolt • cap bolt • lower bracket pinch bolt

ss WARNING

Before loosening the upper and lower brac-ket pinch bolts, support the front fork leg.

4. Remove:• front fork leg

DISASSEMBLY1. Remove:• Clamps (Upper and lower )• Fork boot

2.Remove:• Cap bolt • Spacer • Spring seat • Fork spring

1

3

2

1234

21

3

CHASREMOVAL/DISASSEMBLY

4-39

3. Drain:• Fork oil

4. Remove:• Retaining clip

Use a thin slotted head screwdriver• Washer

CAUTION

Take care not to scratch the inner tube

5. Remove:• Bolt (Damper rod) • Cooper washer

NOTE:

Hold the damper rod to loosen the bolt(Damper rod) by the T-handle and theHolder

6. Remove:• Damper rod • Rebound spring

(Out of inner fork tube )

Damper rod holder90890-01388

T-handle90890-01326

1

2

2

1

3

12

CHASDISASSEMBLY/CHECKING THE FRONT FORK LEGS

4-40

7. Remove:• Inner fork tube

a. Hold the front fork leg horizontally.b. Securely clamp the brake caliper bracket ina vise with soft jaws.c. Separate the inner tube from the outer tube

by pulling the inner tube forcefully but care-fully.

CAUTION

• Excessive force will damage the oil sealand bushing. A damaged oil seal or bus-hing must be replaced.

• Avoid bottoming the inner tube into theouter tube during the above procedure,as the oil flow stopper will be damaged.

EAS00656

CHECKING THE FRONT FORK LEGSThe following procedure applies to both of thefront fork legs.

1. Check:• inner tube • outer tube Bends/damage/scratches Replace.

ss WARNING

Do not attempt to straighten a bent innertube as this may dangerously weaken it.

2. Measure:• spring free length a


Spring free lengthDT125RE 503mm (19.8 in)DT125X 501mm (19.7 in)

1

2

CHASCHECKING THE FRONT FORK LEGS/ASSEMBLING

THE FRONT FORK LEGS

4-41

3. Check:• damper rod • piston ring

Damage/wear Replace.Obstruction Blow out all of the oil pas-sages with compressed air.

• rebound spring Damage Replace.

4. Check:• cap bolt O-ring


EAS00659

ASSEMBLING THE FRONT FORK LEGSThe following procedure applies to both of thefront fork legs.

ss WARNING

• Make sure the oil levels in both front forklegs are equal.

• Uneven oil levels can result in poor hand-ling and a loss of stability.

NOTE:

• When assembling the front fork leg, besure to replace the following parts:- inner tube bushing- outer tube bushing- oil seal- dust seal

• Before assembling the front fork leg, makesure all of the components are clean.

1. Install:• damper rod assembly

CAUTION

Allow the damper rod assembly to slideslowly down the inner tube until it pro-trudes from the bottom of the inner tube. Becareful not to damage the inner tube.

23

1

1

2

CHASASSEMBLING THE FRONT FORK LEGS

4-42

2. Lubricate:• inner tube’s outer surface

3. Tighten:• damper rod assembly bolt

NOTE:

While holding the damper rod assembly withthe damper rod holder and T-handle, tightenthe damper rod assembly bolt.

4. Install:• outer tube bushing

(with the fork seal driver weight and forkseal driver attachment)

5. Install:• washer• oil seal

(with the fork seal driver weight and forkseal driver attachment)

CAUTION

Make sure the numbered side of the oil sealfaces up.

Recommended lubricantFork oil 10W or equivalent

62 Nm (6.2 m•kg, 45 ft•lb)LOCTITE®

Damper rod holder90890-01388

T-handle90890-01326

Fork seal driver weight90890-01367

Fork seal driver attachment90890-01381


4-43

NOTE:

• Before installing the oil seal, lubricate itslips with lithium-soap-based grease.

• Lubricate the outer surface of the inner tubewith fork oil.

• Before installing the oil seal, cover the topof the front fork leg with a plastic bag 2 toprotect the oil seal during installation.

6. Install:• oil seal clip

NOTE:

Adjust the oil seal clip so that it fits into theouter tube’s groove.

7. Install:• dust seal

(with the fork seal driver weight)

8. Fill:• front fork leg

(with the specified amount of the recom-mended fork oil)

Fork seal driver weight90890-01367

Quantity (each front fork leg)DT125RE 0.495 LDT125X 0.6 L

Recommended oilYamaha fork and shock oil 10Wor equivalent

Front fork leg oil level (from thetop of the inner tube, with theinner tube fully compressed andwithout the fork spring)

DT125RE 165.5 mm (6.52 in)DT125X 140mm (5.52 in)


4-44

NOTE:

• While filling the front fork leg, keep itupright.• After filling, slowly pump the front fork legup and down to distribute the fork oil.

9. Install:• spring • spring seat • spacer • cap bolt

NOTE:

• Install the spring with the smaller pitchfacing up.

• Before installing the cap bolt, lubricate itsO-ring with grease.

• Temporarily tighten the cap bolt.

4

3

2

1

CHASSTEERING HEAD AND HANDLEBARS

4-45

STERING HEAD AND HADLEBARS

Handlebar Handlebar grip (Right) Handlebar grip (Left) Handlebar holder (Upper) Handlebar crown Ring nut

10 Cover11 Bearing race12 Headlight stay

A TIGHTENING STEPS•Tightening ring nut

35Nm to 40Nm (3.5 to 4.0 m•kg, 25.6 to 29.3 ft•lb)•Loosen it fully•Retighten it

3Nm to 5Nm (0.3 to 0.5 m•kg, 2.2 to 3.6 ft•lb)

120 to 155 Nm (12 to 15,5 m • kg,88 to 110 ft•lb)

12 to 28 Nm (1,2 to 2,8 m • kg,8,8 to 20,5 ft•lb)

120 to 155 Nm (12 to 15,5 m • kg,88 to 110 ft•lb)

CHASREMOVAL

4-46

REMOVAL1. Elevate the front wheel by placing a suitable

stand under the engine.

ss WARNING

Securely support the motorcycle so there isno danger of falling over

2. Remove:• Front wheel

Refer to the “FRONT WHEEL REMOVAL”section.

• Front forkRefer to the “FRONT FORK REMOVAL”section.

3. Remove:• Bolts (front fender)• Front fender • Washers

4. Remove:• Headlight cover • Headlightn lens unit

5. Disconnect:• Headlight lead• Auxiliary light lead

6. Disconnect:• Flasher light leads

2

3

21

1

CHASREMOVAL

4-47

0

km/h

4060 80

100

120

130

20

y

0 0 0 0 1 5

0 0 0 8

7. Remove:• Flasher lights (left and right) • Brake hose guide

(From left side only)8. Disconnect:• Speedometer cable

9. Remove:• Bands

10. Disconnect:• Meter leads• Handlebar switch leads• Main switch leads• Flasher relay leads

11. Remove:• Bands • Master cylinder assembly

12. Remove:• Brush guard

13. Disconnect:• Clutch cable

(from clutch cable pivot)14. Remove:• Meter assembly

1

23

1

1

4

CHASREMOVAL

4-48

15. Loosen:• Screws (throttle cable housing)

16. Remove:• Handlebar holders • Handlebars

NOTE:

For completely removal of the handlebar, besure to clear the throttle cable housing

17. Remove:• Flange nut • Handlebar crown

18. Remove:• Lock washer • Ring nut 1 • Ring nut 2 • Cover

NOTE:

Remove the ring nut using the Ring Nutwrench

ss WARNING

Support the lower bracket so that it maynot fall down

Ring Nut Wrench:90890-01403

1

1

2

12

12

34

CHASREMOVAL/INSPECTION

4-49

19. Remove:• Bearing cover • Ball race (Top-Upper) • Ball bearing (22pcs)

INSPECTION1. Wash the bearing in solvent.2. Inspect:• Bearings • Bearing races

Pitting/Damage Replace• Dust seal

Wear/Damage Replace

Bearing race replacement steps:• Remove the bearing races on the head

pipe using a long rod and the hammeras shown.

• Remove the bearing race on the steeringstern using the floor chinsel and thehammer as shown.

• Install the new dust seal and races.

NOTE:

• Always replace bearings and races as a set• Replace the dust seat whenever the stee-

ring head is disassembled.

CAUTION

If the bearing race is fitted not squarly, thehead pipe could be damaged

3. Inspect:• Handlebar crown • Under bracket

with steering stemCracks/Bend/Damage Replace

2

1

2

1

2

CHASINSPECTION/INSTALLATION

4-50

4. Inspect:• Handlebar

Cracks/Bend/Damage Replace

ss WARNING

Do not attempt to straighten a bent handle-bar as this may dangerously weaken thehandlebar.

Handlebar replacement steps:• Remove the hadlebar grip and handlebar

switch (Left) and lever holder.• Install the lever holder and handlebar

switch (Left) to a new handlebar.• Apply a light coat of an adhesive for rub-

ber on the left handlebar end.• Install the handlebar grip.

NOTE:

Wipe off any excess adhesive with a clear rag

ss WARNING

Leave the handlebar intact until the adhesi-ve becomes dry enough to make the gripand handlebar stuck securely.

INSTALLATIONReverse the “REMOVAL” procedures.Note the following points

1. Lubricate:• Bearing races • Bearings

2. Install:• Ball bearings

NOTE:

Be sure the balls has the same size and thequantity is correct (22pcs)

Lithium Soap Base Grease

2

11

CHASINSTALLATION

4-51

3. Install:• Ball race (Upper-Lower)• Bearing cover • Under bracket• Ring nut

ss WARNING

Hold the under bracket until its secured

4. Tighten:• Ring nut

Tightening steps:• Tighten the ring nut using the Ring Nut

Wrench

NOTE:

Set the torque wrench to the right nut wrenchso that they form a right angle

• Loosen the ring nut fully• Retighten the ring nut using the Ring Nut

Wrench

ss WARNING

Avoid over tightening

5. Install:• Handlebar crown • Flange nut (Steering stem)

NOTE:

Temporarily tighten the flange bol.

Ring Nut Wrench:90890-01403

Ring Nut (Initial tightening):35Nm to 40Nm (3.5 to 4.0 m·kg,25.6 to 29.3 ft·lb)

Ring Nut (Final tightening):3Nm to 5Nm (0.3 to 0.5 m·kg, 2.2to 3.6 ft·lb)

2

1

2

1

CHASINSTALLATION

4-52

6. Install:• Meter assembly

7. Install:• Front fork

Refer to the “FRONT FORK INSTALLA-TION” section.

NOTE:

In this stage, temporarily tighten the pinchbolts (Handlebar crown).

8. Tighten:• Flange nut (Steering stem) • Pinch bolts (Handlebar crown)

NOTE:

• Install the brake hose guide to the left sideonly.

• On the left side, install the flasher lighthaving a chocolate color lead. Next, installthe other flasher light with a dark greencolor lead.

Bolt (Meter assembly):5Nm to 8Nm (0.5 to 0.8 m·kg, 3.6to 5.8 ft·lb)

Pinch Bolt (Under Bracket):20 to 25Nm (2.0 to 2.5 m·kg, 14.6to 18.3 ft·lb)

Flange nut (Steering stem):120 to 155 Nm (12 a 15.5 m·kg,88to 110ft·lb)

Pinch bolt (Handlebar crown):12 to 28 Nm (1.2 to 2.8 m·kg, 8.80to 20.5ft·lb)

1

2

1

CHASINSTALLATION

4-53

9. Install:• Handlebar• Handlebar holders

NOTE:

The handlebar should be installed in the posi-tion assigned by the position mark

CAUTION

First tighten the bolts on the front side ofthe handlebar holder, and then tighten thebolts on the rear side.

NOTE:

Before installing the handlebar onto the hand-lebar crown, apply a light coat of lithium soapbase grease onto the handlebar end and installthe throttle housing to the handlebar.

10. Install:• Brake master cylinder

NOTE:

• Install the master cylinder bracket with the“UP” mark facing upward.

• Tighten first the upper bolt, then the lowerbolt.

11. Install:• Clutch cable

NOTE:

Apply a light coat of lithium soap base greaseonto the clutch cable end

Bolt (Handlebar holder):12 to 28 Nm (1.2 a 2.8 m·kg, 8.80to 20.5ft·lb)

Bolts (Master cylinder bracket):5 to 8 Nm (0.5 a 0.8 m·kg, 3.6 to5,8ft·lb)

CHASINSTALLATION

4-54

12. Install:• Headlight lens unit

13. Install:• Front wheel

Refer to the “FRONT WHEEL INSTALLA-TION” section.


Refer to the “CLUTCH ADJUSTMENT”section in chapter 3.

Front wheel axle:80 to 100 Nm (8.0 a 10.0m·kg,58.6 to 73.3ft·lb)

Axle security bolts:7.5 to 12 Nm (0.75 to 1.2 m·kg,5.5 to 8.8.5ft·lb)

Free play:2~3mm (0.08~0.12in)

3

1 2

CHASREAR SHOCK ABSORBER AND SWINGARM

4-55

REAR SHOCK ABSORBER AND SWINGARM

Rear shock absorber assembly Spring Bush

A SPRING PRELOAD (INSTALLED):FOR DT125RE

STANDARD LENGTH:230 mm

MINIMUM LENGTH:220 mm

MAXIMUM LENGTH:235 mm

30 to 35 Nm (3,0 to 3,5 m • kg,22 to 25,6 ft•lb)

A SPRING PRELOAD (INSTALLED):FOR DT125X

STANDARD LENGTH:244 mm

MINIMUM LENGTH:234 mm

MAXIMUM LENGTH:249 mm

CHASREAR SHOCK ABSORBER AND SWINGARM

4-56

Swingarm Relay arm Connecting arm Chain case Chain guard Chain guide Collar

Bearing Oil seal10 Bush11 Plain washer12 Shim13 Thrust cover

45 to 70 Nm (4,5 to 7 m • kg,33 to 51,3 ft•lb)

45 to 70 Nm (4,5 to 7 m • kg,33 to 51,3 ft•lb)

80 to 100 Nm (8 to 10 m • kg,58,6 to 73,3 ft•lb)




CHASHANDLING THE REAR SHOCK ABSORBER/DISPO-SING OF A REAR SHOCK ABSORBER/REMOVING

4-57

EAS00686

HANDLING THE REAR SHOCK ABSORBER

ss WARNING

This rear shock absorber contains highlycompressed nitrogen gas. Before handlingthe rear shock absorber, read and makesure you understand the following informa-tion. The manufacturer cannot be held res-ponsible for property damage or personalinjury that may result from improper hand-ling of the rear shock absorber.• Do not tamper or attempt to open the

rear shock absorber.• Do not subject the rear shock absorber

to an open flame or any other source ofhigh heat. High heat can cause an explo-sion due to excessive gas pressure.

• Do not deform or damage the rear shockabsorber in any way. Rear shock absor-ber damage will result in poor dampingperformance.

EAS00688

DISPOSING OF A REAR SHOCKABSORBERGas pressure must be released before dispo-sing of a rear shock absorber. To release thegas pressure, drill a 2 ~ 3-mm hole through therear shock absorber at a point 15 ~ 20 mmfrom its end as shown.

ss WARNING

Wear eye protection to prevent eye damagefrom released gas or metal chips.

EAS00690

REMOVING THE REAR SHOCK ABSORBERASSEMBLY1. Stand the motorcycle on a level surface.

ss WARNING


CHASREMOVING THE REAR SHOCK ABSORBER

ASSEMBLY

4-58

NOTE:


2. Remove:• Bolt (Connecting arm swingarm)

(from swingarm side)

3. Remove:• Bolt (Shock absorber Lower)

ss WARNING

When removing the lower bolt hold theswingarm so that it does not drop down-wards when the lower bolt is removed.

4. Remove:• Bolt (Shock absorber Upper)

5. Remove:• Rear shock absorber

NOTE:

Pull up the swingarm, then remove the rearshock absorber, through between the swin-garm and relay arm

1

21

1

CHASREMOVING THE SWINGARM ASSEMBLY

4-59

REMOVING THE SWINGARM ASSEMBLY

ss WARNING

Securely support the motorcycle so there isno danger of falling it over

1. Elevate the rear wheel by placing a suitablestand under the engine.

2. Remove:• Rear shock absorber

Refer to the “REAR SHOCK ABSORBER”section.


Refer to the “REAR WHEEL REMOVAL”section.

4. Remove:• Brake hose guides • Mud guard

5. Remove:• Protector (Brake caliper) • Brake caliper assembly

6. Remove:• Chain case • Chain guide • Chain guard

3

1

2

21

1


4-60

7. Check:• Swingarm free play

Inspection steps• Check the tightening torque of the pivot

shaft (swingarm) securing nut

• Check the swingarm side play by moving itfrom side to side.If side play noticeable, check the innercollar, bearing, bushing and thrust over, oradjust the shim.

• Check the swingarm vertical movementby moving it up and down.If vertical movement is tight, binding orrough, check the inner collar, bearing, bus-hing and thrust cover or adjust the shim.

8. Remove:• Pivot shaft • Swingarm

9. Remove:• Connecting arm

Nut (Swingarm-Pivot shaft):80 to 100Nm (8 to 10 m·kg; 58.6to 73.3lb·ft)

Side play (At the end of the swin-garm):

1mm (0.04in)1

1

1


4-61

10. Remove:• Relay arm

11. Remove:• Chain protector

12. Remove:• Thrust covers • Inner collars (Swingarm) • Inner collars (Connecting arm) • Inner collar (Relay arm)

1

21

4 22

1

3

CHASCHECKING THE REAR SHOCK ABSORBER

ASSEMBLY

4-62

EAS00695

CHECKING THE REAR SHOCK ABSORBERASSEMBLY1. Check:• rear shock absorber rod

Bends/damage Replace the rear shockabsorber assembly.

• rear shock absorberGas leaks/oil leaks Replace the rearshock absorber assembly.

• springDamage/wear Replace the rear shockabsorber assembly.

• bushingsDamage/wear Replace.

• dust sealsDamage/wear Replace.

• boltsBends/damage/wear Replace.

EAS00707

CHECKING THE SWINGARM1. Check:• swingarm

Bends/cracks/damage Replace.

2. Check:• pivot shaft

Roll the pivot shaft on a flat surface.Bends Replace.

ss WARNING

Do not attempt to straighten a bent pivotshaft.

3. Wash:• pivot shaft• dust covers• spacer• washers• bearings

Recommended cleaning solventKerosene

CHASCHECKING THE SWINGARM

4-63

4. Check:• dust covers • spacer • washers • oil seals

Damage/wear Replace.• bearings

Damage/pitting Replace.

5. Check:• connecting arms • relay arm


6. Check:• bearings • oil seals

Damage/pitting Replace.

1 34

2

24 3 1

1

1

29 8

2

1

1

2

CHASCHECKING THE SWINGARM/INSTALLING THE

SWINGARM

4-64

7. Check:• spacers

Damage/scratches Replace.

EAS00711

INSTALLING THE SWINGARM1. Lubricate:• bearings• spacers• dust covers• pivot shaft

2. Install:• relay arm

• connecting arms

NOTE:

Install the connecting arm front bolt fromthe right.

3. Install:• rear shock absorber assembly• rear wheel

Refer to “INSTALLING THE REAR SHOCKABSORBER ASSEMBLY” and “INSTA-LLING THE REAR WHEEL”.

45 to 70 Nm (4.5 to 7.0m•kg, 33to 95.5ft•lb)

Recommended lubricantMolybdenum disulfide grease

45 to 70 Nm (4.5 to 7.0m•kg, 33to 95.5ft•lb)

CHASINSTALLING THE SWINGARM

4-65

4. Adjust:• drive chain slackRefer to “ADJUSTING THE DRIVE CHAINSLACK” in chapter 3.

Drive chain slackDT125RE 40~55mm (1,77~2,16in.)DT125X 25~40mm (0,98~1,58 in.)

CHASDRIVE CHAIN AND SPROCKETS

4-66

DRIVE CHAIN AND SPROCKETS

Drive sprocket Chain joint Drive chain


A DRIVE CHAINB TYPE

428V2C No. OF LINKS

134D DRIVE CHAIN SLACK DT125RE

45~55mm(1,77~2,16in)

E DRIVE CHAIN SLACK DT125X25~40mm(0,984~1,575in)

CHASREMOVING THE DRIVE CHAIN

4-67

REMOVING THE DRIVE CHAIN1. Stand the motorcycle on a level surface.

ss WARNING


NOTE:


2. Remove:• Crankcase cover (left)

3. Straighten:• Lock washer tab

4. Loosen:• Nut (drive sprocket)

NOTE:

When loosening the drive sprocket nut, applythe rear brake pedal and transmission gear tothe 6th position.

5. Remove:• Clip (master link) • Plate (master link) • master link • O-rings • Drive chain

6. Remove:• Chain guide • Drive sprocket


Refer to the “REAR WHEEL REMOVAL”section.

12

3

4

4 2 1

1

1

CHASREMOVING THE DRIVE CHAIN/CHECKING THE DRIVE

CHAIN

4-68

8. Remove:• Chain guide rollers (Upper and lower)

EAS00709

CHECKING THE DRIVE CHAIN1. Measure:• ten-link section a of the drive chain

Out of specification Replace the drivechain.

2. Check:• drive chain

Stiffness Clean and lubricate or repla-ce.

3. Clean:• drive chain

a. Wipe the drive chain with a clean cloth.b. Put the drive chain in kerosene and remove

any remaining dirt.c. Remove the drive chain from the kerosene

and completely dry it.

Ten-link drive chain section limit(maximum)

120 mm (4.72 in)

CHASCHECKING THE DRIVE CHAIN

4-69

CAUTION

This motorcycle has a drive chain withsmall rubber O-rings between the drivechain side plates. Never use high-pressurewater or air, steam, gasoline, certain sol-vents (e.g., benzine), or a coarse brush toclean the drive chain. High-pressure met-hods could force dirt or water into the drivechain’s internals, and solvents will deterio-rate the O-rings. A coarse brush can alsodamage the O-rings. Therefore, use onlykerosene to clean the drive chain. Don’tsoak drive chain in kerosine more them tenminutes. O-ring is damage by kerosine.

4. Check:• O-rings

Damage Replace the drive chain.• drive chain rollers

Damage/wear Replace the drive chain.• drive chain side plates

Damage/wear Replace the drive chain.Cracks Replace the drive chain andmake sure the battery breather hose isproperly routed away from the drive chainand below the swingarm.

5. Lubricate:• drive chain

6. Check:• drive sprocket• rear wheel sprocket

More than 1/4 tooth a wear Replacethe drive chain sprockets as a set.Bent teeth Replace the drive chainsprockets as a set.

b Correct Drive chain roller Drive chain sprocket


CHASINSTALLING THE DRIVE CHAIN

4-70

EAS00713

INSTALLING THE DRIVE CHAIN1. Lubricate:• drive chain• master link <NEW>

2. Install:• drive chain • drive sprocket • washer • drive sprocket nut

NOTE:

While applying the rear brake, tighten the drivesprocket nut.

3. Install:• master link • O-ring • master link plate

(with a drive chain cutter)

CAUTION

Never install a new drive chain onto worndrive chain sprockets; this will dramaticallyshorten the drive chain’s life.

4. Adjust:• drive chain slack

Refer to “ADJUSTING THE DRIVE CHAINSLACK” in chapter 3.


60 Nm (6.0 m•kg, 43 ft•lb)

Drive chain slack DT125RE45 ~ 55 mm (1.77 ~ 2.16 in)

Drive chain slack DT125X25 ~ 40 mm (0.984 ~ 1.575 in)

4

2

3

1

2

3

CHASINSTALLING THE DRIVE CHAIN

4-71

CAUTION

A drive chain that is too tight will overloadthe engine and other vital parts, and onethat is too loose can skip and damage theswingarm or cause an accident. Therefore,keep the drive chain slack within the speci-fied limits.

ENG

5

CHAPTER 5ENGINE

ENGINE REMOVAL……………………………………………………………………5-1SIDE COVERS …………………………………………………………………5-1COOLANT ………………………………………………………………………5-1TRANSMISSION OIL …………………………………………………………5-1EXHAUST PIPE ………………………………………………………………5-2CARBURETOR …………………………………………………………………5-2AUTOLUBE PUMP CABLE AND HOSE ……………………………………5-2CLUTCH CABLE ………………………………………………………………5-3Y.P.V.S. CABLES ………………………………………………………………5-3RADIATOR HOSE………………………………………………………………5-4LEADS …………………………………………………………………………5-4DRIVE CHAIN …………………………………………………………………5-5

ENGINE DISASSEMBLY…………………………………………………………5-6CYLINDER HEAD, CYLINDER AND PISTON ………………………………5-8CLUTCH, PRIMARY DRIVE GEAR AND BALANCER GEAR ……………5-8CLUTCH PUSH LEVER………………………………………………………5-11SHIFT SAHFT AND STOPPER LEVER ……………………………………5-11MAGNETO ROTOR …………………………………………………………5-12REED VALVE …………………………………………………………………5-12CRANKCASE (RIGHT) ………………………………………………………5-13SHIFTER, TRANSMISSION AND BALANCER WEIGHT …………………5-14CRANKSHFT …………………………………………………………………5-15POWER VALVE ………………………………………………………………5-15AUTOLUBE PUMP ASSEMBLY ……………………………………………5-16

INSPECTION AND REPAIR……………………………………………………5-17CYLINDER HEAD ……………………………………………………………5-17CYLINDER AND PISTON ……………………………………………………5-18PISTON RINGS ………………………………………………………………5-19PISTON PIN AND BEARING ………………………………………………5-21CLUTCH ………………………………………………………………………5-21PRIMARY DRIVE ……………………………………………………………5-24TRANSMISSION AND SHIFTER ……………………………………………5-25SHIFT SHAFT AND STOPPER LEVER ……………………………………5-27CRANKSHAFT ………………………………………………………………5-27AUTOLUBE PUMP …………………………………………………………5-28POWER VALVE ………………………………………………………………5-29CRANKCASE …………………………………………………………………5-30

ENGINE ASSEMBLY AND ADJUSTMENTS ………………………………5-31AUTOLUBE PUMP …………………………………………………………5-31POWER VALVE ………………………………………………………………5-33CRANKSHAFT AND BALANCER …………………………………………5-35TRANSMISSION AND SHIFTER ……………………………………………5-36CRANKCASE (RIGHT) ………………………………………………………5-39REED VALVE …………………………………………………………………5-40MAGNETO ROTOR …………………………………………………………5-41STOPPER LEVER AND SHIFT SHAFT ……………………………………5-43CLUTCH PUSH LEVER………………………………………………………5-46BALANCER GEAR, PRIMARY DRIVE GEAR AND CLUTCH ……………5-47PISTON CYLINDER AND CYLINDER HEAD………………………………5-52REMOUNTING ENGINE ……………………………………………………5-56

ENG

ENGENGINE REMOVAL

5-1

ENGINE OVERHAULENGINE REMOVAL

NOTE:

It’s not necessary to remove the engine inorder to remove the following components:• Cylinder head• Cylinder• Piston and piston ring• Power valve• Clutch• Primary drive gear• Kick axle• Shift shaft• Magneto rotor• Stator• Autolube pump

SIDE COVERS1. Remove:• Side cover (right)• Side cover (left)• Seat

COOLANT1. Drain:• Coolant

Refer to the “COOLANT REPLACEMENT”section in chapter 3.

TRANSMISSION OIL


Refer to the “TRANSMISSION OIL REPLA-CEMENT” section in chapter 3.

ENGENGINE REMOVAL

5-2

EXHAUST PIPE1. Loosen:• Bolts (Exhaust holder) • Screw (muffler joint)

2. Remove:• A.I.S. hose • Bolts (Exhaust pipe) • Exhaust pipe

CARBURETOR1. Remove:• Fuel tank• Carburetor

Refer to the “CARBURETOR REMOVAL”section in chapter 6.

AUTOLUBE PUMP CABLE AND HOSE1. Remove:• Autolube pump cover

2. Disconnect:• hose

(from autolube pump and hose guide)• Gasket (autolube pump cover

NOTE:

Plug the oil hose so that oil will not run out ofthe oil tank.

3. Remove:• Pump cable

NOTE:

Turn the pump pulley clockwise by finger tomake the pump cable loose enough for its endto be removed from the pulley.

1

1

21

1

2

1

3

ENGENGINE REMOVAL

5-3

2

1

CLUTCH CABLE1. Loosen:• Adjuster (Clutch cable)

2. Loosen:• Adjuster lock nuts (Clutch cable)

3. Disconnect:• Clutch cable

(from clutch push lever and cable guide).

Y.P.V.S. CABLES1. Remove:• Pulley cover (Power valve)

2. Remove:• Pulley (Power valve)

Removal steps• Loosen both locknuts and turn in both

adjusters .• Insert a pin (Ø4mm.(Ø0.16in)) through the

aligning indent in the pulley and into thehole to lock the pulley.

• Remove the pulley from the power valveand then disconnect the Y.P.V.S. cables from the pulley.

• Remove the pin

1

2

55

1

4

2

3

4

2

1

3

ENGENGINE REMOVAL

5-4

3. Disconnect:• Servomotor unit leads

4. Remove:• Servomotor unit • Adjuster (Y.P.V.S. cable) • Pulley housing

RADIATOR HOSES1. Disconnect:• Radiator hose (Inlet)

2. Disconnect:• Radiator hose (Outlet)

LEADS1. Disconnect:• Battery lead (Negative)

2. Disconnect:• Spark plug lead • Thermo unit lead

1

32

1

1

2

1

ENGENGINE REMOVAL

5-5

3. Disconnect:• CDI magneto leads

4. Remove:• Bands

DRIVE CHAIN1. Remove:• Change pedal • Crankcase cover (Left) • Gasket (Crankcase cover)


3. Loosen:• Nut (Drive sprocket)

NOTE:

When loosening the nut (Drive sprocket) applythe rear brake pedal and transmission gear tothe 6th position

4. Remove:• Drive chain• Nut (Drive sprocket) • Lock washer • Drive sprocket • Spacer collar

ENGINE REMOVAL1. Remove:• Bolts (Engine stay Upper) • Bolts (Engine mount Front)

2 1

12

1

1

5

4

2

3

1

2

ENGENGINE REMOVAL/

ENGINE DISASSEMBLY

5-6

2. Remove:• Bolt (Engine mount Rear lower)• Pivot shaft

NOTE:

The engine and swingarm are installed usingthe same pivot shaft. Therefore, take care sothat the pivot shaft is pulled, not entirely, out,but for enough to set the engine free.

3. Remove:• Engine assembly

(from right side)

ENGINE DISASSEMBLYCYLINDER HEAD, CYLINDER AND PISTON

NOTE:

With the engine mounted, the cylinder head,cylinder and piston can be maintained byremoving the following parts.• Side covers (Right and left)• Seat• Radiator cover• Oil tank cover• Fuel tank• Radiator hose (inlet)• Servomotor unit (Y.P.V.S.)• Engine stay (Upper)• Exhaust pipe

1. Remove:• Hoses (Inlet and Outlet )1

2

12

ENGENGINE DISASSEMBLY

5-7

2. Remove:• Spark plug • Thermo unit

ss WARNING

Handle the thermo unit with special care.Never subject it to strong or allow it to bedropped. In case of being dropped, it mustbe replaced.

3. Remove:• Cover (thermostatic valve)

4. Remove:• Gasket • Thermostatic valve • O-ring

5. Remove:• Cylinder head• Gasket (Cylinder head)

NOTE:

• Loosen the nuts starting with the highestnumbered one.

• Loosen each nut 1/4 turn, and remove themafter all nuts are loosened.

6. Remove:• Clutch cable guide• Cylinder • Gasket (Cylinder)• Dowel pins

NOTE:

Loosen each nut 1/4 turn, and remove themafter all nuts are loosened.

2

1

32 1

5 2

4

1

3

1


5-8

EAS00253

REMOVING THE CYLINDER AND PISTON1. Remove:• piston pin clip • piston pin • piston

CAUTION

Do not use a hammer to drive the piston pinout.

NOTE:

• Before removing the piston pin clip, coverthe crankcase opening with a clean rag toprevent the piston pin clip from falling intothe crankcase.

• Before removing the piston pin, deburr thepiston pin clip’s groove and the piston’spin bore area. If both areas are deburredand the piston pin is still difficult to remo-ve, remove it with the piston pin puller set.

2. Remove:• top ring• 2nd ring• oil ring

NOTE:

When removing a piston ring, open the endgap with your fingers and lift the other side ofthe ring over the piston crown.

CLUTCH, PRIMARY DRIVE GEAR ANDBALANCER GEAR

NOTE:

With the engine mounted, the clutch, primarydrive gear and balancer gear can be maintai-ned by removing the following parts:

• Brake pedal• Radiator hose (Outlet)• Autolube pump cable and hoses• Crankcase cover (Right)

Piston pin puller set90890-01304

3

2

1


5-9

1. Remove:• Water outlet pipe • O-Ring

(from water outlet pipe)

Right side Left side

2. Remove:• Crankcase cover (Right)• Dowel pins• Gasket (Crankcase cover)

3. Remove:• Bolts • Clutch springs • Pressure plate • Push rod #1 • Friction plates • Clutch plates • Clutch dumper • Nut (Clutch boss) • Lock washer • Clutch boss 10

• Thrust washer 11

• Clutch housing 12

• Thrust plate 13

• Conical spring washer 14

• Boll 15

• Push rod #2 16

12 3

89

76

510

11

12 1314

4

1516

2

1


5-10

NOTE:

• Before loosening the nut (Clutch boss) straighten the lock washer tab.

• Hold the clutch boss to loosen the nut(Clutch boss) by the universal Clutch hol-der


5. Loosen:• Nut (Primary drive gear) • Nut (Balancer gear)

NOTE:

Hold the magneto rotor to loosen the nut (pri-mary drive gear) and nut (Balancer drivengear) by the universal rotor holder

6. Remove:• Nut (Balancer driven gear) • Lock washer • Driven gear (Balancer weight) • Straight key• Nut (Primary drive gear) • Plain washer • Primary drive gear • Baffle plate

7. Remove:• Drive gear (Balancer weight) • Straight key

Universal Clutch Holder90890-04086

Universal Rotor Holder90890-01235

13

2

3 21

6 5

7

2

1

2

1

8


5-11

8. Remove:• Spacer collar • Oil seal retainer

CLUTCH PUSH LEVER1. Unhook:• Return spring (Push lever)

2. Remove:• Push lever (Clutch) • Return spring • Washer

SHIFT SHAFT AND STOPPER LEVER

NOTE:

With the engine mounted, the shift shaft canbe maintained by removing the following parts.• Brake pedal• Radiator hose (Outlet)• Autolube pump cable and hoses• Crankcase cover (Right)• Clutch

1. Remove:• Shift shaft

CAUTION

When removing the shift shaft, hold theguide bar (shift fork) 2 in place. Otherwise,the guide bar will come loose with the shiftshaft, leaving the shift fork out of order inthe crankcase.

2. Remove:• Stopper lever • Return spring

2 3

4

1

2

1

1 2

1


5-12

ROTOR

NOTE:

With the engine mounted, the rotor can bemaintained by removing the following parts:• Crankcase cover (Left).

1. Remove:• Nut (Rotor) • Plain washer

NOTE:

Hold the rotor to loosen the nut (Rotor) by theUniversal Rotor Holder

2. Remove:• Rotor • Woodruff key

3. Disconnect:• Neutral switch lead

4. Remove:• Stator

REED VALVE

NOTE:

With the engine mounted, the reed valve canbe maintained by removing the following parts:• Side covers (Right and Left)• Seat• Radiator cover• Oil tank cover• Fuel tank• Carburetor

Universal Rotor Holder90890-01235

Rotor Puller90890-01189


5-13

1. Remove:• Carburetor joint • Reed valve assemby • Gasket

CRANKCASE RIGHT1. Remove:• Crankcase (Right)

NOTE:

• Loosen the bolts starting with the highestnumbered one.

• Loosen each bolt 1/4 turn and removethem after all bolts are loosened.

Removal steps:• Attach the Crankcase Separating Tool

NOTE:

Fully tighten the tool holding bolts, but makesure the tool body is parallel with the case. Ifnecessary, one screw may be backed outslightly to evel tool body.

• As pressure is applied alternately tap onthe front engine mounting boss, transmis-sion shafts and shift cam.Then remove the crankcase (Right).

NOTE:

Turn the shift cam to the position shown inthe figure so that it doesn’t contact the crank-case when separating the crankcase.

Crankcase Separating Tool:90890-01135

1

3

2

1

1


5-14

CAUTION

• Use soft hammer to tap on the case half.• Tap only on reinforced portions of case.• Don’t tap on gasket mating surface.• Work slowly and carefully.• Make sure the case halves separate

evenly. If one end “hangs up”, take pres-sure off the push screw, realign, andstart over. If the cases don’t separate,check for a remaining case screw or fit-ting.

• Don’t force.

2. Remove:• Dowel pins • Damper collar

3. Remove:• Bearing retainer

SHIFTER, TRANSMISSION AND BALANCERWEIGHT1. Remove:• Guide bars • Shift cam • Shift forks

NOTE:

Note the position of each part. Pay particularattention to the location and direction of shiftforks.

2. Remove:• Transmission assembly

Tap lightly on the transmission drive axlewith a soft hammer.

1

1

2

1

2

31


5-15

3. Remove:• Balancer weight

CRANKSHAFT1. Remove:• Crankshaft

NOTE:

• Remove the crankshaft with the CrankcaseSeparating Tool

• Fully tighten the tool holding bolts, butmake sure the tool body is parallel with thecase. If necessary, one screw may be bac-ked out slightly to level tool body.

POWER VALVE

NOTE:

With the engine mounted, the power valve canbe maintained by removing the following parts:• Side covers• Seat• Radiator cover• Cover (engine oil tank)• Fuel tank• Servomotor unit

Crankcase Separating Tool:90890-01135

1

12


5-16

1. Remove:• Hose guide • Power valve holder (Right)

2. Remove:• Bolt (Power valve)

NOTE:

When loosening the power valve connectingbolt , lock the valve by inserting a woodenpice into the exhaust port.

3. Remove:• Power valve (Right) • Power valve (Left) • Dowel pins • Holder (Power valve)• Gasket seal

AUTOLUBE PUMP ASSEMBLY

NOTE:

With the engine mounted, the autolube pumpassembly can be maintained by removing thefollowing parts:• Brake pedal• Radiator hose (Outlet)• Autolube pump cable and hoses• Kick crank• Crankcase cover (Right)

2

1

2

13 2

ENGENGINE DISASSEMBLY/

INSPECTION AND REPAIR

5-17

1. Remove:(ref. oilpump)• Circlip• Drive gear (autolube pump)• Circlip• Oil seal• Collar• Pin• Drive shaft (autolube pump)• O-Ring• Autolube pump

EAS00227

CHECKING THE CYLINDER HEAD1. Eliminate:• combustion chamber carbon deposits

(with a rounded scraper)

NOTE:

Do not use a sharp instrument to avoid dama-ging or scratching:• spark plug bore threads• valve seats

2. Check:• cylinder head

Damage/scratches Replace.

3. Measure:• cylinder head warpage

Out of specification Resurface the cylin-der head.

Maximum cylinder head warpage0.03 mm (0,0012 in)

8

5

76

43

12

1

ENGINSPECTION AND REPAIR

5-18

a. Place a straightedge and a thicknessgauge across the cylinder head.

b. Measure the warpage.c. If the limit is exceeded, resurface the cylin-

der head as follows.d. Place a 400 ~ 600 grit wet sandpaper on

the surface plate and resurface the cylinderhead using a figure-eight sanding pattern.

NOTE:

To ensure an even surface, rotate the cylinderhead several times.

EAS00255

CHECKING THE CYLINDER AND PISTON1. Check:• piston wall• cylinder wall

Vertical scratches Rebore or replace thecylinder, and replace the piston and pistonrings as a set.

2. Measure:• piston-to-cylinder clearance

a. Measure cylinder bore “C” with the cylinderbore gauge.

NOTE:

Measure cylinder bore “C” by taking side-to-side and front-to-back measurements of thecylinder. Then, find the average of the measu-rements.

Cylinder bore gauge56.00 ~ 56.02 mm (2.2047 ~2.2055 in)


5-19

Standard LimitCylinder Bore “C” 56.00 ~ 56.02 mm

(2.204 ~ 2.205 in)Taper “T” — 0.05 mm

(0.001968 in)Out of — 0.01 mmround “R” (0.00039 in)C = maximum of D1 ~ D2T = maximum of D1 or D2 - maximum of D5 or D6R = maximum of D1, D3 or D5 - minimum of D2, D4 or D6

b. If out of specification, rebore or replace thecylinder, and replace the piston and pistonrings as a set.

c. Measure piston skirt diameter “P” with themicrometer.

Piston size “P”Standard 56.34 ~ 56.40 mm

(2.218 ~ 2.220 in)Oversize 56.65 mm (2.23 in)Oversize 56.90 mm (2.24 in)d. If out of specification, replace the piston

and piston rings as a set.e. Calculate the piston-to-cylinder clearance

with the following formula.Piston-to-cylinder clearance =Cylinder bore “C” -Piston skirt diameter “P”

f. If out of specification, rebore or replace thecylinder, and replace the piston and pistonrings as a set.

EAS00264

CHECKING THE PISTON RINGS1. Measure:• piston ring side clearance

Out of specification a Replace the pis-ton and piston rings as a set.

Micrometer90890 - 03008

Piston-to-cylinder clearance0.045 ~ 0.050 mm (0.0018 ~

0.0020 in)Limit: 0.1 mm (0.004 in)


5-20

NOTE:

Before measuring the piston ring side clearan-ce, eliminate any carbon deposits from thepiston ring grooves and piston rings.

2. Install:• piston ring

(into the cylinder)

NOTE:

Level the piston ring into the cylinder with thepiston crown.

3. Measure:• piston ring end gap

Out of specification Replace the pistonring.

NOTE:

The oil ring expander spacer’s end gap cannotbe measured. If the oil ring rail’s gap is exces-sive, replace all three piston rings.

Piston ring side clearanceTop ring

0.02 ~ 0.060 mm (0.0008 ~0.0024 in)

2nd ring0.035 ~ 0.070 mm (0.0014 ~0.0028 in)

Piston ring end gapTop ring

0.3 ~ 0.45 mm(0.012 ~ 0.018 in)

2nd ring0.30 ~ 0.45 mm(0.012 ~ 0.018 in)


5-21

Piston ring oversize• Top and 2nd piston rings

The size of the top and 2nd oversize pistonrings is stamped on the top of each ring.

Oversize 25 mm

Oversize 50 mm

PISTON PIN AND BEARING1. Lubricate:• Small end bearing • Piston pin

(Lightly)2. Install:• Small end bearing • Piston pin

(into small end of connecting rod)

3. Check:• Free play

There should be no noticeable play. Freeplay exists Inspect the connecting rodfor wear/Replace the pin and/or connec-ting rod as required.

4. Install:• Piston pin

(into piston pin hole)

5. Check:• Free play (when the piston pin is in place

in the piston). There should be no noticeable play. Freeplay exists Inspect the connecting rodfor wear/Replace the pin and/or connec-ting rod as required.

6. Inspect:• Piston pin and bearing

Signs of heat discoloration Replace

EAS00280

CHECKING THE FRICTION PLATESThe following procedure applies to all of thefriction plates.1. Check:• friction plate

Damage/wear Replace the frictionplates as a set.

2

3

1

3


5-22

2. Measure:• friction plate thickness

Out of specification Replace the fric-tion plates as a set.

NOTE:

Measure the friction plate at four places.

EAS00281

CHECKING THE CLUTCH PLATESThe following procedure applies to all of theclutch plates.1. Check:• clutch plate

Damage Replace the clutch plates asa set.

2. Measure:• clutch plate warpage

(with a surface plate and thickness gauge)Out of specification Replace theclutch plates as a set.

EAS00282

CHECKING THE CLUTCH SPRINGSThe following procedure applies to all of theclutch springs.

1. Check:• clutch spring

Damage Replace the clutch springsas a set.

Friction plate thickness2.9 ~ 3.1 mm (0.11 ~ 0.12 in)<Limit>: 2.7 mm

Clutch plate warpage limit0.05 mm (0.001 in)


5-23

2. Measure:• clutch spring free length

Out of specification Replace theclutch springs as a set.

EAS00284

CHECKING THE CLUTCH HOUSING1. Check:• clutch housing dogs

Damage/pitting/wear Deburr the clutchhousing dogs or replace the clutch housing.

NOTE:

Pitting on the clutch housing dogs will causeerratic clutch operation.

2. Check:• bearing

Damage/wear Replace the bearing andclutch housing.

EAS00285

CHECKING THE CLUTCH BOSS1. Check:• clutch boss splines

Damage/pitting/wear Replace the clutchboss.

NOTE:

Pitting on the clutch boss splines will causeerratic clutch operation.

EAS00286

CHECKING THE PRESSURE PLATE1. Check:• pressure plate

Cracks/damage Replace.• bearing


Clutch spring free length34,5mm (1.36 in)

1


5-24

EAS00288

CHECKING THE CLUTCH PUSH RODS1. Check:• O-ring • short clutch push rod • long clutch push rod • ball

Cracks/damage/wear Replace thedefective part(s).

2. Measure:• long clutch push rod bending limit

Out of specification Replace the longclutch push rod.

EAS00292

CHECKING THE PRIMARY DRIVE1. Check:• primary drive gear• primary driven gear

Damage/wear Replace the primarydrive and primary driven gears as a set.Excessive noise during operation

Replace the primary drive and primary dri-ven gears as a set.

2. Check:• primary-drive-gear-to-primary-driven-gear

free playFree play exists Replace the primarydrive and primary driven gears as a set.

Long clutch push rod bending limit0.15 mm (0.0059 in)

34

21


5-25

EAS00421

CHECKING THE SHIFT FORKSThe following procedure applies to all of theshift forks.1. Check:• shift fork cam follower • shift fork pawl

Bends/damage/scoring/wear Replacethe shift fork.

2. Check:• shift fork guide bar

Roll the shift fork guide bar on a flat surface.Bends Replace.

ss WARNING

Do not attempt to straighten a bent shiftfork guide bar.

3. Check:• shift fork movement

(along the shift fork guide bar)Rough movement Replace the shiftforks and shift fork guide bar as a set.

EAS00422

CHECKING THE SHIFT DRUM ASSEMBLY1. Check:• shift drum grooves

Damage/scratches/wear Replace theshift drum assembly.

• shift drum segment Damage/wear Replace the shift drumassembly.

• shift drum bearing Damage/pitting Replace the shift drumassembly.

2

1


5-26

EAS00423

CHECKING THE TRANSMISSION1. Measure:• main axle runout

(with a centering device and dial gauge )Out of specification Replace the mainaxle.

2. Measure:• drive axle runout

(with a centering device and dial gauge )Out of specification Replace the driveaxle.

3. Check:• transmission gears

Blue discoloration/pitting/wear

Replace the defective gear(s).• transmission gear dogs

Cracks/damage/rounded edges

Replace the defective gear(s).

4. Check:• transmission gear engagement

(each pinion gear to its respective wheelgear)Incorrect Reassemble the transmis-sion axle assemblies.

5. Check:• transmission gear movement

Rough movement Replace the defec-tive part(s).

6. Check:• circlips

Bends/damage/looseness Replace.

Main axle runout limit0.08 mm (0.0031 in)

Drive axle runout limit0.08 mm (0.0031 in)


5-27

EAS00328

CHECKING THE SHIFT SHAFT1. Check:• shift shaft • shift pawls

Bends/damage/wear Replace.2. Check:• stopper lever

Roller turns roughly ReplaceBend/damage Replace

3. Check:• Return spring (shift shaft) • Return spring (Shift pawls) • Return spring (Stopper lever)

Wear/damage Replace.

EAS00394

CHECKING THE CRANKSHAFT AND CONNECTING ROD1. Measure:• crankshaft runout

Out of specification Replace thecrankshaft, bearing or both.

NOTE:

Turn the crankshaft slowly.

2. Measure:• big end side clearance

Out of specification Replace the bigend bearing, crankshaft pin, or connectingrod.

Maximum crankshaft runout0.03 mm (0.0012 in)

5

2

1

4

3

6

Big end side clearance0.2~0.7mm (0.0079~0.0276in)


5-28

3. Measure:• crankshaft width

Out of specification Replace thecrankshaft.

4. Check:• crankshaft sprocket

Damage/wear Replace the cranks-haft.

• bearing Cracks/damage/wear Replace thecrankshaft.

AUTOLUBE PUMPWear or an internal malfunction may causepump output to vary from the factory settings.This situation is, however extremely dange-rous.If improper output is suspected, inspectthe following:1. Inspect:• Delivery line

Obstructions Blow out.• Pump body seal/crankcase cover seal


2. Inspect:• Allowing air

Air exists Air bleed.Refer to the “AUTOLUBE PUMP AIR BLE-EDING” section in chapter 3.

Crankshaft width57.9~57.95 mm (2.279~2.281 in)

1

2

2

1

2 4 3

56

10

9

13

78

1114

1214


5-29

3. Check:• Pump output.


4. Check:• Drive gear (Autolube pump) • Drive shaft (Autolube pump) • Pivot collar (Drive shaft)


POWER VALVE1. Eliminate:• Score marks and lacquer deposits.• Carbon deposits.

(from power valve , specially in cleaninggroove surface, and its contact surfaceof cylinder block).

2. Check:• O-rings • Bushes • Gsket seals

Wear/damage Replace

Minimum output/200 stroke:0.38 ~ 0.50cm3 (0.02 ~ 0.03cu.in)

Maximum output/200stroke:4.65 ~ 5.15cm3 (0.28 ~ 0.31cu.in)

8

5

76

43

12

1

1

1 23

1

2


5-30

EAS00399

CHECKING THE CRANKCASE1. Thoroughly wash the crankcase halves in a

mild solvent.2. Thoroughly clean all the gasket surfaces

and crankcase mating surfaces.3. Check:• crankcase

Cracks/damage Replace.• oil delivery passages

Obstruction Blow out with compressedair.

ENGENGINE ASSEMBLY AND ADJUSTMENTS

5-31

AUTOLUBE PUMP

5 Nm (0.5 m • kg, 3.6ft•lb)

Autolube pump End cap Hose Clip Adjusting bolt Washer Drive shaft

Collar O-Ring10 Screw11 Oil seal12 Autolube pump gear13 Pin14 Circlip


5-32

AUTOLUBE PUMP1. Lubricate:• Oil seal lips

2. Install:• Drive shaft (autolube pump) • Circlip • Pin • Drive gear (autolube pump) • Circlip • O-ring • Autolube pump

ss WARNING

• Always use a new circlip• Always use a new O-ring

Lightweight Lithium-soap basegrease

Screw (Autolube pump):5 Nm (0.5m•kg; 3.6ft·lb)

8

5

76

43

12

1


5-33

POWER VALVE

Power valve Power valve holder (right) O-ring Power valve holder (left) Gasket seal

Pulley housing Pulley Pulley cover Y.P.V.S. Cable

7 Nm (0.7 m • kg, 5.1ft•lb)

7 Nm (0.7 m • kg, 5.1ft•lb)

7 Nm (0.7 m • kg, 5.1ft•lb)

A USE NEW ONE

A USE NEW ONE

10 Nm (1.0 m • kg, 7.2ft•lb)


5-34

POWER VALVE1. Lubricate:• Power valve connecting rod

• O-rings • Gasket seal • Bushes

(Power valve shaft contact surface)• Power valve surface

2. Install:• Power valve holder (Left) • Gasket seal (to left power valve)

• Dowel pins • Power valve (Left and right )

(to cylinder block)• Bolt (Power valve)

3. Tighten:• Bolt (Power valve)

NOTE:

When tightening the power valve connectingbolt , lock the valve by insterting a woodenpice into the exhaust port.

4. Install:• Power valve holder

5. Check:• Power valve operation

Unsmooth operation Repair.

Molybdenum Disulfide Grease

Lightweight Lithium-soap basegrease

Bolt (Power Valve):7 Nm (0.7 m•kg; 5.1 ft•lb)

Bolt (Power Valve Holder):7 Nm (0.7 m•kg; 5.1 ft•lb)

3 4

2

3

2

5

2 31

1

2

2

1

1

4


5-35

CRANKSHAFT/PISTON/BALANCER

Balancer gear Bearing Straight key Balancer weight Bearing Drive gear Oil seal Collar

Bearing10 Piston ring set11 Piston12 Piston pin13 Piston pin clip14 Small end bearing15 Staight key16 Crank (Right)

17 Thrust bearing18 Connecting rod19 Crank pin20 Big end bearing21 Crank (Left)22 Wodruff key23 Bearing24 Oil seal

A PISTON TO CYLINDER CLEARANCE:0.045~0.050 mm(0.0018~0.0020in)

B EN GAP (INSTALLED):Top ring0.30~0.45mm(0.012~0.018in)2rd ring0.30~0.45mm(0.012~0.018in)

C CRANKSHAFTWidth 57.90~57.95mm

(2.279~2.271in)

Max Runout 0.03mm (0.012in)

Big end side clearance 0.2~0.7mm(0.0079~0.0276in)

Big end radial clearance 0.026~0.040mm(0in)

D BALANCER GEAR INSTALLATION


5-36

TRANSMISSION

Main axle 2nd pignion gear 3rd 4th pignion gear 5th pignion gear 6th pignion gear Plain washer Circlip Bearing

Cylindrical bearing10 Drive axle11 1st wheel gear12 2nd wheel gear13 3rd wheel gear14 4th wheel gear15 5th wheel gear16 6th wheel gear

19 Special washer20 Oil seal21 Drive sprocket22 Lock washer

A RUNOUT LIMIT008mm(0.003in)

B USE NEW ONE

B USE NEW ONE

B USE NEW ONE

B USE NEW ONE

A RUNOUT LIMIT0.08mm(0.003in)


5-37

SHIFTER

Shift cam Stopper lever Return spring Securing bolt Shift fork #1

Shift fork #2 Shift fork #3 Shift fork #1 Shift fork #2

14 Nm (1.4 m • kg,10ft•lb)


5-38

EAS00408

INSTALLING THE CRANKSHAFT1. Install:• crankshaft assembly

NOTE:

• Install the crankshaft assembly with thecrankshaft installer pot, crankshaft installerbolt, adapter (M12) and spacer.

2. Install:• crankshaft assembly

CAUTION

To avoid scratching the crankshaft and toease the installation procedure, lubricatethe oil seal lips with lithium-soap-basedgrease and each bearing with engine oil.

NOTE:

Hold the connecting rod at top dead center(TDC) with one hand while turning the nut ofthe crankshaft installer bolt with the other. Turnthe crankshaft installer bolt until the crankshaftassembly bottoms against the bearing.

EAS00427

INSTALLING THE SHIFT FORKS ANDSHIFT DRUM ASSEMBLY1. Install:• shift fork guide bars • shift fork “3” • shift fork “2” • shift fork “1”

Crankshaft installer pot90890-01274

Crankshaft installer bolt90890-01275

Adapter (M12)90890-01278

Spacer90890-01288

1

3

2


5-39

NOTE:

• The embossed marks mqRA.anq on theshift forks should face towards the left sideof the engine and be in the followingsequence: “3”, “2”, “1”.

• The grooved side of the shift fork guide barshould face towards the right side of theengine.

CRANKCASE (RIGHT)1. Install:• Bearing retainer

2. Apply:• yamaha Bond nº4

(to mating surface of both crankcase hal-ves)

3. Install:• Damper collar • Dowel pins

4. Install:• Crankcase (Right)

Installation steps:• Apply the lithium soap base grease to the

oil seal lips.• Fit the right crankcase onto the left case.

Tap lightly on the case with a soft hammer.

NOTE:

Turn the shift cam to the position shown in thefigure so that it doesn’t contact the crankcasewhen installing the crankcase.

• Install the water outlet pipe stay • Tighten the bolts (Crankcase)

Screw (Bearing retainer):7 Nm (0.7 m•kg; 5.1 ft•lb)Use Loctite®

Yamaha Bond nº4:90890-05143

1

1

3

23


5-40

CAUTION

Before installing and torquing the bolts(Crankcase) be sure to check wheter thetransmission is functioning properly bymanually rotating the shift cam either way.

NOTE:

Tighten the bolts (Crankcase) in stage, using acrisscross pattern.

5. Apply:• 2 stroke oil(to crank pin, bearing and oil delivery hole).

6. Check:• Crankshaft and transmission operationUnsmooth operation Repair.

REED VALVE1. Install:• Breather hose (Crankcase) • Gasket • Reed valve assembly • Carburetor joint

ss WARNING

• Always use a new gasket.• A damaged gasket may cause the enginerevs to accelerate.

2. Tighten:• Bolts (Carburetor joint)

Bolts(Crankcase):8 Nm (0.8 m•kg; 5.8 ft•lb)

Bolts(Carburator joint):8 Nm (0.8 m•kg; 5.8 ft•lb)

3

21


5-41

MAGNETO ROTOR

Stator assembly Rotor Washer

80 Nm (8.0 m • kg, 58ft•lb)


5-42

MAGNETO ROTOR1. Install:• Stator

2. Connect:• Neutral switch lead

3. Install:• Woodruf key • Rotor • Plain washer • Nut (Rotor)

NOTE:

• Clean the tapered portions of the cranks-haft and rotor.

• When installing the rotor, make sure thekey is properly seated in the key way ofthe crankshaft.

• Hold the rotor by the Rotor Holder to tigh-ten the nut

Screw(Stator):8 Nm (0.8 m•kg; 5.8 ft•lb)Use Loctite®

Universal Rotor Holder:90890-01235

Nut (Rotor):80 Nm (8.0 m•kg; 58 ft•lb)

1

1

1

2 3 4


5-43

SHIFT SHAFT

Shift tank Spring Circlip Oil seal Change pedal

15 Nm (1.5 m • kg, 11ft•lb)


5-44

STOPPER LEVER AND SHIFT SHAFT1. Install:• Return spring • Stopper lever

NOTE:

• Mesh the stopper lever with the shift cam.

2. Install:• shift shaft

NOTE:

• Lubricate the oil seal lips with lithium-soap-based grease.

3. Check:• shift pawl position

Gaps a and b are not equal

Replace the defective part(s).

Shift cam

CLUTCH PUSH LEVER1. Lubricate:• Bearing • Oil seal lip • Washer • Push lever axle

14Nm (1.4m•kg, 10 ft•lb)


4

321

1

2

1

1

1

(a)

(b)


5-45

2. Install:• Washer • Return spring • Push lever

3. Set the return spring to the spring hook.

3

1 2

4


5-46

CLUTCH AND PRIMARY DRIVE GEAR

Clutch spring Pressure plate Push plate Clutch plate Friction plate Clutch damper Clutch boss Thrust washer Clutch housing

10 Thrust plate11 Conical spring washer12 Push rod #113 Ball14 Push rod #215 Push lever axle16 Return spring17 Bearing18 primary drive gear

A CLUTCH SPRING FREE LENGHTLIMIT: 34.5 mm(1.26in)

B FRICTION PLATE WEAR LIMIT2.7 mm(0.106in)

C CLUTCH PLATE WEAR LIMIT:0.05 mm(0.002in)

70 Nm (7.0m • kg, 50ft•lb)

80 Nm (8.0 m • kg, 58ft•lb)


5-47

BALANCER GEAR, PRIMARY DRIVE GEARAND CLUTCH

1. Install:• Oil seal retainer • Spacer collar

NOTE:

Before installing the spacer collar greae theoil seal lip .

2. Install:• Straight key • Drive gear (Balancer weight) • Baffle plate

3. Install:• Driven gear (Balancer weight) • Straight key

CAUTION

Align the balancer drive gear mark 3 withthe balancer driven gear mark 4

4. Install:• Lock washer • Nut (Balancer driven gear) • Plain washer • Nut (Primary drive gear)

NOTE:

Install the lock washer tab into the key wayof the balancer driven gear .

Oil Seal Retainer:16 Nm (1.6 m•kg; 11 ft•lb)

Screw (Baffle Plate):8 Nm (0.8 m•kg; 5.8 ft•lb)Use Loctite®

3

21

21

3

2

1

1

23

4


5-48

ss WARNING

Always use a new lock washer

5. Tighten:• Nut (Primary drive gear) • Nut (Balancer driven gear)

NOTE:

Hold the rotor to tighten the nut (Primary drivegear) and nut (Balancer driven gear) bythe Universal Rotor Holder

6. Bend the lock washer tab along the nutsflats.

7. Lubricate:• Push rod #2• Ball

Nut (Primary drive gear):80 Nm (8.0 m•kg; 58 ft•lb)Nut (Balancer driven gear):55 Nm (5.5 m•kg; 40 ft•lb)

Universal Rotor Holder:90890-01235


8

9 87

5 43

2 1

3

2

1


5-49

8. Install:• Push rod #2• Ball • Conical spring washer • Thrust plate • Clutch housing • Thrust washer • Clutch boss • Lock washer • Nut (Clutch boss)

ss WARNING

Always use a new lock washer

NOTE:

• Be careful to install the conical spring was-her in proper position as shown.

• Install the lock washer tab onto theindentation of the clutch boss.

9. Tighten:• Nut (Clutch boss)

NOTE:

Hold the clutch boss to tighten the nut (clutch boss) by the Universal Clutch Holder

10. Bend the lock washer tab along the nutflats.

Nut (Clutch boss):70 Nm (7.0 m•kg; 50 ft•lb)

Universal Clutch Holder:90890-04086

8

9 87

5 43

2 1

2


5-50

11. Install:• Friction plates • Clutch plates • Clutch damper

Installation steps• Install the friction plate onto the clutch

boss.• Install the clutch plate so as to locate the

projection at #1.• Install the friction plate with the larger insi-

de diameter onto the clutch boss.• Install the clutch damper onto the clutch

plate.• Install the remaining clutch plates and fric-

tion plates alternately on the clutch boss.• Be sure to install a clutch plate with pro-

jection offset aproximately 60º from pre-vious plate projection.Continue this procedure in a clockwisedirection until all clutch plates are installed.

NOTE:

Before installing friction and clutch plates, sinkthem into transmission oil almost 3 hoursbefore mounting

12. Install:• Push rod #1 • Pressure plate • Clutch springs • Bolts (Pressure plate)

NOTE:

Align the punched mark on the clutch bosswith the punched mark on the clutch pres-sure plate.

13. Tighten:• Bolts (Pressure plate)

Bolt (Pressure plate):6 Nm (0.6 m•kg; 4.8 ft•lb)

32

1

43 2

1


5-51

NOTE:

Tighten the bolts (pressure plate) in stage,using a crisscross pattern

14. Adjust:• Clutch mechanism free play

Refer to the “CLUTCH MECHANISMADJUSTMENT” section in chapter 3.

15. Install:• Gasket (Crankcase cover) • Dowel pins• Crankcase cover (Right) • Drain plug (Transmission oil) • Drain plug (Coolant)

NOTE:

Tighten the screws (Crankcase cover) in stageusing a crisscross pattern

ss WARNING

Always use a new gasket

16. Apply the grease to the O-ring17. Install:• O-ring

(to water outlet pipe )• Water outlet pipe

ss WARNING

Always use a new O-ring

Screw (Crankcase cover):8 Nm (0.8 m•kg; 5.8 ft•lb)

Drain plug (Transmission Oil):15Nm (1.5 m•kg; 11 ft•lb)

Drain plug (Coolant):10Nm (1.0 m•kg; 7.2 ft•lb)

Screw (Water Outlet Pipe):8 Nm (0.8 m•kg; 5.8 ft•lb)

2

1

13


5-52

CYLINDER HEAD AND CYLINDER

Spark plug Cylinder head Cylinder head gasket Cylinder Cylinder gasket

A SPARK PLUG

B MANUFACTURERNGK

C TYPE:BR9ES

D PLUG GAP:0.7~0.8mm(0.028~0.0012in)

E CYLINDER HEADWARRAGE LIMIT:

0.03mm(0.0012in)

13 Nm (1.3m • kg, 9.4ft•lb)

20 Nm (2.0m • kg, 14ft•lb)

13 Nm (1.3m • kg, 9.4ft•lb)

22 Nm (2.2m • kg, 16ft•lb)

F USE NEW ONE

F USE NEW ONE

G The “UP” mark on thegasket musb be facing up

28 Nm (2.8m • kg, 20ft•lb)


5-53

PISTON, CYLINDER AND CYLINDER HEAD1. Install:• Bearing• Piston • Piston pin • Piston pin clips

NOTE:

• Apply engineoil tothe piston pin, bearingsand piston skirts areas.

• Make sure the arrow mark on the pistonpoints towards the exhaust side of thecylinder.

• Before installing the piston pin clip, coverthe crankcase opening with a clean rag toprevent the clip from falling into the crank-case.

ss WARNING

Always use a new piston pin clip

CAUTION

Do not allow the clip open ends to meet thepiston pin slot

2. Check:• Piston ring position

CAUTION

• Make sure ring ends are properly fittedaround ring locating pins in piston groo-ves.

• Be sure to check te manufacture’s marksor numbers stamped on the rings are onthe top side of the rings.

4

2

3

4

1


5-54

3. Install:• Dowel pins • Gasket <NEW> (Cylinder)

ss WARNING


4. Install:• Cylinder • Clutch cable guide

NOTE:

Install the cylinder with one hand while com-pressing the piston rings with the other hand

5. Tighten:• Nuts (cylinder)

NOTE:

Tighten the nuts ins stage using a crisscrosspattern.

6. Install:• Gasket (Cylinder head)• Cylinder head

ss WARNING


NOTE:

The “UP” mark on the gasket must be facingup

7. Tighten:• Nuts (Cylinder head)

NOTE:

Tighten the nuts in stage, using a crisscrosspattern

Nut (Cylinder):28 Nm (2.8 m•kg, 20 ft•lb)

Nut (Cylinder Head):22 Nm (2.2 m•kg, 16 ft•lb)

NEW1

2

1

5

2

4

1

3


5-55

8. Install:• O-ring • Thermostatic valve • Gasket

NOTE:

Apply the lithium soap base grease to the O-ring

ss WARNING

• Always use a new O-ring.• Always use a new gasket.

9. Install:• Cover (Thermostatic valve)

10. Install:• Spark plug • Thermo unit

ss WARNING

Handle the thermo unit with special care.Never subject it too strong or allow it to bedropped. In case of being hited, replace it.

Screw (Thermostatic Valve Cover):8 Nm (0.8 m•kg, 5.8 ft•lb)

Spark plug:20 Nm (2.0 m•kg, 14 ft•lb)

Thermo unit:15 Nm (1.5 m•kg, 11 ft•lb)

1

3 2

1

2 1


5-56

11. Install:• Hoses (Inlet and outlet )

REMOUNTING THE ENGINEReverse the “ENGINE REMOVAL” procedure.Note the following points:1. Install:• Engine assemb

(to right side)• Mounting bolts

NOTE:

• Apply lithium soap base grease to thepivot shaft.

• Temporary tighten the bolts before tighte-ning them to specification.

2. Install:• Spacer collar • Drive sprocket • Lock washer • Nut (Drive sprocket) • Drive chain

NOTE:

Before installing the spacer collar applygrease to the oil seal lip.

Union bolt:8 Nm (0.8 m•kg, 5.8 ft•lb)

Pivot shaft :90 Nm (9.0 m•kg, 65 ft•lb)

Bolt (Rear Lower):33 Nm (3.3 m•kg, 24 ft•lb)

Bolt (Front):58 Nm (6.8 m•kg, 42 ft•lb)

Bolt (Engine stay Upper):33 Nm (3.3 m•kg, 24 ft•lb)

Nut (Drive sprocket):60 Nm (6.0 m•kg, 43 ft•lb)

1

23

4


5-57

3. Bend the lock washer tab along the nut flats4. Install:• Gasket (Crankcase cover)• Crankcase cover (Left) • Change pedal

NOTE:

Tighten the screws (Crankcase cover) in stage,using a crisscross pattern.

5. Adjust:• Drive chain slack

Refer to the “DRIVE CHAIN SLACKADJUSTMENT” section in chapter 3.

6. Connect:• Radiator hose (Outlet) • Radiator hose (Inlet)

7. Install:• Pulley housing • Adjusters (Y.P.V.S. cables) • Servomotor unit

Screw (Crankcase cover):8 Nm (0.8 m•kg, 5.8 ft•lb)

Bolt (Change pedal):15 Nm (1.5 m•kg, 11 ft•lb)

Bolt (Pulley housing):8 Nm (0.8 m•kg, 5.8 ft•lb)

Screw (Servomoto unit):7 Nm (0.7 m•kg, 5.1 ft•lb)

1 2

2

1

2

1


5-58

2

1

8. Connect:• Servomotor unit lead • Cables (Y.P.V.S.)

(to power valve pulley)

9. Install:• Pulley (power valve)

10. Adjust:• Y.P.V.S. cables

Refer to the “Y.P.V.S. CABLE ADJUST-MENT” section in chapter 3.

NOTE:

Before adjusting the Y.P.V.S. cables, turn themain switch “ON” and operate the Y.P.V.S.motor.

11. Install:• Pulley cover (Power valve)


Refer to the “CLUTCH ADJUSTMENT”section in chapter 3.

Bolt (Power valve pulley):10Nm (1.0 m•kg, 7.2 ft•lb)

Bolt (Pulley Cover):7 Nm (0.7 m•kg, 5.1 ft•lb)

1

1

1


5-59


Refer to the “AUTOLUBE PUMP AIR BLE-EDING” section in chapter 3.


15. Install:• Gasket (Exhaust pipe)• Exhaust pipe

ss WARNING


16. Fill:• Radiator• Reservoir tank (Radiator)


Bolt (Autolube pump cover):5 Nm (0.5 m•kg, 3.6 ft•lb)

Nut (Exhaust pipe):18 Nm (1.8 m•kg, 13 ft•lb)

Bolt (Stay):10 Nm (1.0 m•kg, 7.2 ft•lb)

Bolt (Frame mount):10 Nm (1.0 m•kg, 7.2 ft•lb)Screw (Muffler joint):10 Nm (1.0 m•kg, 7.2 ft•lb)

Total amount:0,92L

1

23

1

4


5-60



Total amount:0,92L

COOL

6

CHAPTER 6COOLING SYSTEM

WATER PUMP ……………………………………………………………………6-1REMOVAL ………………………………………………………………………6-2INSPECTION……………………………………………………………………6-4INSTALLATION …………………………………………………………………6-4

THERMOSTATIC VALVE AND RADIATOR ……………………………………6-7REMOVAL ………………………………………………………………………6-8INSPECTION …………………………………………………………………6-10INSTALLATION ………………………………………………………………6-11

COOL

COOLWATER PUMP

6-1

COOLING SYSTEMWATER PUMP

Impeller shaft Oil Seal Pin Impeller shaft gear Plain washer Circlip

Water pump housing cover Gasket Dowel pin10 Drain bolt11 Gasket

8 Nm (0.8 m • kg, 5.8 ft•lb)

A USE NEW ONE

A USE NEW ONE

COOLWATER PUMP

6-2

REMOVAL

NOTE:

It is necessay to disassemble the water pumpunless there is no abnormality such as exces-sive change in coolant temperature and/or dis-coloration of coolant or milky transmission oil.



• CoolantRefer to the “COOLANT REPLACEMENT”section in chapter 3.

2.Disconnect:• Outlet hose (Radiator)

3.Remove:• Screw (Water outlet pipe)

4. Remove:• Autolube pump cover

5. Disconnect:• Oil delivery hose

6. Remove:• Gasket (Autolube pump cover) • Stopper clip (Pump cable)• Clip (Pump cable outer) • Autolube pump cable

NOTE:

• Plug the oil hose so that oil will not run outof the oil tank.

• Turn the pump pulley counterclockwise byfinger to make the pump calbe looseenough for its end to be removed from thepulley.

3

2

1

2

1

COOLWATER PUMP

6-3

7. Remove:• Return spring • Bolt (Master cylinder) • Brake pedal • Crankcase cover

8. Remove:• Water outlet pipe • Housing cover (Water pump) • Gasket• Dowel pins

9. Remove:• Circlip • Plain washer • Impeller shaft gear

10. Remove:• Pin • Plain washer

11. Remove:• Impeller shaft

12. Eliminate deposits from the impeller andwater pump housing.

42 3

2

1

1 2 3

1

2

1

1

COOLWATER PUMP

6-4

EAS00472

CHECKING THE WATER PUMP1. Check:• O-ring

Damage/wear Replace.• oil seal

Damage/wear Replace the water pumphousing assembly.

2. Check:• impeller

Cracks/damage/wear Replace the waterpump housing assembly.

• bearingRough movement Replace the waterpump housing assembly.

Oil seal replacement steps:• Remove the oil seal from the crankcase

cover by tapping it towards the outside.• Install the new oil seal with the “WATER

SIDE” mark on the outside.

NOTE:

• Apply the lightweight lithium base grease tooil seal outside.

• Press fit the oil seal until it contacts the bot-tom.

INSTALLReverse the “REMOVAL” procedure. Note thefollowing points.1. Apply:• Lightweight lithium base grease

(to oil seal lips and impeller shaft)

2. Install:• Impeller shaft

Install the shaft while turning it.

NOTE:

Take care so that the oil seal lip is not dama-ged or the spring doesn’t slip off its position.

1

COOLWATER PUMP

6-5

3. Install:• Housing cover (Water pump) • Water outlet pipe

CAUTION

• Always use new gaskets• Always use a new O-ring

4. Install:• Crankcase cover (Right) • Brake pedal • Return spring • Drain plug (Transmission oil) • Drain plug (Coolant)

NOTE:

Before installing the brake pedal apply lithiumsoap base grease to the brake pedal pivotshaft.

ss WARNING

Always use new cotter pin and gasket.

5. Install:• Screw (Water outlet pipe)


Screw (Brake pedal):20 Nm (2.0 m•kg, 14 ft•lb)

Drain plug (Transmission Oil):15 Nm (1.5 m•kg, 11 ft•lb)

Drain plug (Coolant):10 Nm (1.0 m•kg, 7.2 ft•lb)

Screw (Water Outlet pipe):8 Nm (0.8 m•kg, 5.8 ft•lb)


Screw (Water Outlet Pipe):8 Nm (0.8 m•kg, 5.8 ft•lb)

1

1

1

2

3 2

5

4

COOLWATER PUMP

6-6



7. Fill:• Radiator

Refer to the “COOLANT REPLACEMENT”section.


Refer to the “AUTOLUBE PUMP AIR BLEE-DING” section.


Total amount:0,92L

Screw (Autolube pump cover):5 Nm (0.5 m•kg, 3.6 ft•lb)

Recommended Oil:SAE 10W30 type SE Motor Oil

Periodic Oil Change:0,75L

COOLTHERMOSTATIC VALVE AND RADIATOR

6-7

THERMOSTATIC VALVE AND RADIATOR

Radiator assembly Radiator cap Inlet hose Coolant breather hose Outlet hose Gasket

Hose (Carburetor warmer Inlet) Hose (Carburetor warmer Inlet) Thermostatic valve cover10 Gasket11 Thermostatic valve12 O-ring

8 Nm (0.8 m • kg, 5.8 ft•lb)

D USE NEW ONE

8 Nm (0.8 m • kg, 5.8 ft•lb)

8 Nm (0.8 m • kg,5.8 ft•lb)

8 Nm (0.8 m • kg, 5.8 ft•lb)

D USE NEW ONE

D USE NEW ONE

D USE NEW ONE

B COOLANT CAPACITY:0.92L Including all routes

C THERMOSTATIC VALVE OPENINGTEMPERATURE:

63~67°C (146~153°C)

A RADIATOR CAP OPENING PRESSURE:75~105kPA(0.75~1.05kg/cm2, 10~14psi)


6-8

REMOVAL1. Remove:• Side covers (Left and Right)• Seat• Exhaust pipe

2. Remove:• Radiator cover• Oil tank cover• Fuel tank

Refer to the “CARBURETOR REMOVAL”section in chapter 7.

3. Drain:• Cooling system


NOTE:

Thoroughly flush the cooling system with cleantap water.

CAUTION

Take care so that coolant doesn’t splashpainted surfaces. If splashes, wash it awaywith water.

ss WARNING

Do not remove the radiator cap, drain boltsand hoses specially when the engine andthe radiator are hot. Scalding hot fluid andsteam may be blown out under pressure,wich could cause serious injury. When theengine has cooled, place a thick rag like atowel over the radiator cap, slowly rotatethe cap counterclockwise to detent. Thisproceduce allows any residual pressure toescape. When the hissing sound stops,press down the cap while turning counter-clockwise to remove it.

1

1


6-9

4. Remove:• Radiator cap

5. Disconnect:• Breather hose (Radiator )

6. Remove:• Inlet hose (Radiator) • Outlet hose (Radiator)

7. Remove:• Water outlet pipe • O-ring

8. Remove:• Radiator fin

9. Remove:• Radiator

2

1

4

21 3


6-10

10. Remove:• Thermostatic valve cover• Gasket • Thermostatic valve • O-ring

EAS00455

CHECKING THE RADIATOR1. Check:• radiator fins

Obstruction Clean.Apply compressed air to the rear of theradiator.Damage Repair or replace.

NOTE:

Straighten any flattened fins with a thin, flat-head screwdriver.

2. Check:• radiator hoses• radiator pipes

Cracks/damage Replace.

3. Measure:• radiator cap opening pressure

Below the specified pressure Replacethe radiator cap.

Radiator cap opening pressure75~ 105 kPa(0.75 ~ 1.05 kg/cm2, 10 ~ 14 psi)

3


6-11

a. Install the radiator cap tester and radiatorcap tester adapter to the radiator cap.

b. Apply the specified pressure for tenseconds and make sure there is no drop inpressure.

4. Inspect:• Thermostatic valve

Valve doesn’t open at 63~67ºC (146~153ºF) Replace.

INSTALLATIONReverse the “REMOVAL” procedure. Note thefollowing points.1. Install:• O-ring • Thermostatic valve • Gasket • Thermostatic valve cover

ss WARNING

Always use new O-ring and gasket

Screw (Thermostatic Valve Cover):8 Nm (0.8 m·kg; 5.8 ft·lb)

3

2

1

Radiator cap tester90890-01325

Radiator cap tester adapter90890-01352

12


6-12

FULL

LOW

2. Install:• Radiator

3. Apply grease to the O-ring 4. Install:• O-ring • Water outlet pipe

ss WARNING

Always use a new O-ring

5. Fill:• Radiator• Reservoir tank (Radiator)


6. Inspect:• Cooling system

Decrease of pressure (leaks)Repair asrequired

Screw (Water Outlet Pipe):8 Nm (0.8 m·kg; 5.8 ft·lb)

2

1

Bolt(Radiator):8 Nm (0.8 m·kg; 5.8 ft·lb)

1


6-13

Inspection steps• Attach the Cooling System Tester to the

radiator

• Apply 100kPa (1.0 kg/cm2, 14psi) pressure.• Measure the indicated pressure with the

gauge.

Radiator cap tester90890-01325

CARB

7

CHAPTER 7CARBURETOR

CARBURETOR ……………………………………………………………………7-1REMOVAL ………………………………………………………………………7-2DISASSEMBLY …………………………………………………………………7-3INSPECTION……………………………………………………………………7-4ASSEMBLY ……………………………………………………………………7-6INSTALLATION …………………………………………………………………7-8ADJUSTMENT …………………………………………………………………7-9

REED VALVE ……………………………………………………………………7-10REMOVAL ……………………………………………………………………7-11DISASSEMBLY ………………………………………………………………7-11INSPECTION …………………………………………………………………7-12ASSEMBLY ……………………………………………………………………7-12INSTALLATION ………………………………………………………………7-13

CARB

CARBCARBURETION

7-1

CARBURETIONCARBURETOR

Cap Throttle valve spring Starter plunger Throttle stop screw Pilot air screw Throttle valve Needle set

Pilot jet Needle jet10 Gasket11 Main jet12 Needle valve assembly13 Float14 Drain screw

Main Jet (M.J.) #210Main Air Jet (M.A.J.) ø 0.8Jet Needle (J.N.) 5J40-2Needle Jet (N.J.) Q2-M (#939)Pilot Jet (P.J.) #17.5Power Jet (PW.J.) #60Pilot Air Screw (P.A.S.)Float Height (F.H.) 15.5~16.5mm(0.61~0.65in)Engine Idling Speed 1250~1450 rev/min.speed:

CARBCARBURETOR

7-2

REMOVAL

NOTE:

The following parts can be cleaned and ins-pected without disassembly• Throttle valve• Starter plunger• Throttle stop screw

1. Remove:• Side cover (Left and Right) • Seat• Radiator cover

2. Turn the fuel cock to “OFF” position.3. Disconnect:• Fuel hose

(from carburetor side)

4. Remove:• Fuel tank

ss WARNING

Gasoline is highly flammable. Avoid spillingfuel over the engine when it’s hot

5. Disconnect:• Reservoir tank (Rear brake) • Y.E.I.S. system

12

REAR

1

1

CARBCARBURETOR

7-3

6. Disconnect:• Hoses• Oil delivery hose• Cooling hoses

7. Loosen:• Screw (carburetor joint) • Screw (air box)

8. Remove:• Carburetor top• Carburetor

9. Remove:• Cable holder• Throttle valve• Return spring

DISASSEMBLY1. Remove:• Hoses

2. Remove:• Starter plunger assembly

3 Remove:• Float chamber • Gasket float chamber

1

1

1

1

1

2

1

2

1

CARBCARBURETOR

7-4

4. Remove:• Float pin • Float • Needle valve

5. Remove: • Valve seat • Main jet • Jet needle holder

6. Remove:• Throttle stop screw • Pilot air screw

INSPECTION1. Inspect:• Carburetor mixing chamber body

Contamination Clean

NOTE:

Use petroleum based solvent for cleaning.Blow out all passages and jets with compres-sed air.

2. Inspect:• Carburetor float chamber body

Contamination Clean

NOTE:

Starter jet and all air jets are fixed type

2

13

2

1

1

CARBCARBURETOR

7-5

3. Inspect:• Valve seat • Gasket • Needle valve

NOTE:

Always replace the needle valve and valve seatas a set.

4. Inspect:• Starter plunger

Wear/Contamination Replace5. Check:• Free movement

Stick ReplaceInsert the throttle valve into the carburetorbody and check for free movement.

6. Inspect:• Throttle stop screw • Pilot air screw • O-ring

Wear/Damage Replace

7. Inspect:• Jet needle

Bends/Wear Replace

8. Inspect:• Throttle valve

Wear/Damage Replace9. Check:• Free movement

Stick ReplaceInsert the throttle valve into the carburetorbody, and check for free movement.

1

CARBCARBURETOR

7-6

10. Inspect:• Float

Damage Replace

11. Inspect:• Main jet • Needle jet• Pilot jet

Contamination Clean

NOTE:

Blow out the jets with compressed air

ASSEMBLYReverse the “DISASSEMBLY” procedures.Note the following points.

CAUTION

Before reassembling, wash all parts withclean gasoline

1. Tighten:• Jet needle holder

2. Install:• Valve seat • Main jet • Pilot jet • Needle jet

NOTE:

Align the knock pin with the pin slot in theneedle jet

3. Measure:• Float height a

Out of specification Adjust

Float height (F.H.):15.5~16.5mm (0.61~0.65in)

2 4

1

1

CARBCARBURETOR

7-7

Measurement and adjustment steps:• Hold the carburetor in an upside down

position.• Measure the distance from the mating sur-

face on the float chamber (gasket removed)to the top of the float.

CAUTION

The float arm should be resting on the needlevalve, but not compressing the needle valve.

• If the float height is not within specification,inspect the valve seat and needle valve.

• If either is worn, replace them both.• If both are fine, adjust the float height by

bending the float tang on the float.• Recheck the float height.

4. Install:• Float chamber • Hose • Gasket (float chamber)

ss WARNING


5. Tighten:• Screws (Float chamber)

6. Install:• Starter plunger

Screw (Float chamber)2 Nm (0.2 m·kg; 1.4 ft·lb)

1

23

1

1

CARBCARBURETOR

7-8

7. Intall:• Throttle valve

NOTE:

Align the groove of the throttle valve with theprojection of the carburetor body.

INSTALLATIONReverse the “REMOVAL” procedures. Note thefollowing points.1. Install:• Carburetor assembly

NOTE:

Align the groove of the carburetor joint with theprojection of the carburetor body.

2. Adjust:• Idle speed

Refer to the “IDLE SPEED ADJUSTMENT”section in chapter 3.

3. Adjust:• Carburetor cable free play.

Refer to the “THROTTLE CABLE FREEPLAY ADJUSTMENT” section in chapter 3.

4. Adjust:• Carburetor cable free play

Refer to the “CARBURETOR CABLE FREEPLAY ADJUSTMENT” section in chapter 3.

Engine idle speed1250~1450 rev/min

Throttle cable free play:3-5mm 0’11-0,19in.

Carburetor cable free play:1mm (0.04in.)

CARBCARBURETOR

7-9

ADJUSTMENTFuel level adjustment1. Measure:• Fuel level

Out of specification adjust

Fuel level measurement and adjustmentsteps:• Place the motorcycle on a level surface.• Use a garage jack under the engine to

ensure that the carburetor is positioned ver-tically.

• Connect the fuel level gauge to the drainpipe .

• Loosen the drain screw and warm up theengine for several minutes.

• Measure the fuel level with tha gauge.• If the level is incorrect, adjust the fuel level.• Remove the carburetor.• Inspect the valve seat and needle valve.• If either is worn, replace them both.• If both are fine, adjust the float level by ben-

ding the float tang slightly.• Install the carburetor.• Recheck the fuel level.

Fuel level:1.5~2.5mm (0.05~0.09in.)In the middle of the FloatChamber. Below the carburetorBody edge.

Fuel level gauge:90890-01312

CARBREED VALVE

7-10

REED VALVE

Reed valve assembly Reed valve Stopper plate Gasket Carburetor joint Y.E.I.S. Chamber

10 Nm (1.0 m • kg, 7.2 ft•lb)

B USE NEW ONE

1 Nm (0.1 m • kg, 0.7 ft•lb)

CARBREED VALVE

7-11

REMOVAL1. Remove:• Carburetor

Refer to the “CARBURETOR REMOVAL”section.

2. Remove:• Carburetor joint

3. Remove:• Reed valve assembly • Gasket

DISASSEMBLY1. Remove:• Y.E.I.S. chamber

2. Remove:• Reed valve stopper • Reed valve

1

2

1

2

1

1

CARBREED VALVE

7-12

INSPECTION1. Inspect:• Reed valve • Reed valve stopper Cracks/Damage Replace

2. Measure:• Reed valve bending limit


Surface plate

3. Measure:• Reed valve stopper height


Surface plate

4. Inspect:• Carburetor joint • Y.E.I.S. chamber

Cracks/Damage Replace.

ASSEMBLYReverse the “DISASSEMBLY” precedure. Notethe following points.1. Install:• Reed valves• Reed valve stoppers

NOTE:

• Place the reed valve with its concave sidefacing the reed valve seat.

Reed valve Bending Limit:0.5mm (0.02in)

Reed valve Stopper Height:6.8mm (0.27in)

2

1

2

1

CARBREED VALVE

7-13

• Fit the reed valve stopper out with thecorresponding cut on the reed valve.

2. Tighten:• Screws (Reed valve)

NOTE:

Tighten each screw gradually to avoid war-ping.

3. Install:• Y.E.I.S. chamber

NOTE:

The arrow on the Y.E.I.S. chamber must pointforward.

INSTALLATIONReverse the “REMOVAL” procedure. Note thefollowing points.1. Install:• Gasket (New) • Reed valve assembly

ss WARNING

A damaged gasket may cause the enginerevs to accelerate. Always use a new gas-ket.

2. Install:• Carburetor joint

Screws (Reed valve):1 Nm (0.1 m·kg; 0.7 ft·lb) UseLOCTITE®

Bolt (Carburetor joint):10 Nm (1.0 m·kg; 7.2 ft·lb)

1

2

1

1

ELEC

8

CHAPTER 8ELECTRICAL SYSTEM

DT125RE CIRCUIT DIAGRAM …………………………………………………8-1COLOR CODE …………………………………………………………………8-1

ELECTRICAL COMPONENTS …………………………………………………8-2CHECKING SWITCH CONTINUITY …………………………………………8-4CHECKING THE SWITCHES …………………………………………………8-5

IGNITION SYSTEM ………………………………………………………………8-6CIRCUIT DIAGRAM ……………………………………………………………8-6IGNITION CONTROL CIRCUIT OPERATION ………………………………8-6TROUBLESHOOTING …………………………………………………………8-8

CHARGING SYSTEM …………………………………………………………8-14CIRCUIT DIAGRAM …………………………………………………………8-14TROUBLESHOOTING ………………………………………………………8-15

LIGHTING SYSTEM ……………………………………………………………8-16CIRCUIT DIAGRAM …………………………………………………………8-16TROUBLESHOOTING ………………………………………………………8-17

SIGNALING SYSTEM …………………………………………………………8-26CIRCUIT DIAGRAM …………………………………………………………8-26TROUBLESHOOTING ………………………………………………………8-27

COOLING SYSTEM ……………………………………………………………8-38CIRCUIT DIAGRAM …………………………………………………………8-38TROUBLESHOOTING ………………………………………………………8-39

YAMAHA POER VALVE SYSTEM ……………………………………………8-42CIRCUIT DIAGRAM …………………………………………………………8-42TROUBLESHOOTING ………………………………………………………8-43

METER ASSEMBLY ……………………………………………………………8-46REMOVAL ……………………………………………………………………8-47INSTALLATION ………………………………………………………………8-48

ELEC

ELECDT125RE CIRCUIT DIAGRAM

8-1

ELECTRICALDT125RE CIRCUIT DIAGRAM

B BlackR RedO OrangeL BlueP PinkY YellowG GreenW White

Ch ChocolateDg Dark greenSb Sky blueBr BrownL/Y Blue/YellowB/Y Black/YellowB/W Black/WhiteB/R black/Red

W/R White/RedW/L White/BlueY/R Yellow/RedG/R Green/RedG/Y Green/YellowG/W Green/WhiteBr/W Brown/WhiteL7R Blue/Red

ELECELECTRICAL COMPONENTS

8-2

ELECTRICAL COMPONENTS(1)

CDI Unit Servomotor Battery Fuse Neutral switch

Thermo unit Rectifier/Regulator Ignition coil Main switch

Ignition coil:Primary coil resistance:

0.23 Ω at 20 °CSecondary coil resistance:

7.9 kΩ at 20 °C

ELECELECTRICAL COMPONENTS

8-3

ELECTRICAL COMPONENTS(2)

Flasher relay Conductor wire Rectifier 2 Oil gauge

Sidestand switch Brake switch Relay Horn

Battery:Capacity:

12V 6AhNo maintenance

ELECCHECKING SWITCH CONTINUTY

8-4

LOCK

OPEN

OFF

CHECK

ON

GY Br R B

a

b

BW/

EAS00730

CHECKING SWITCH CONTINUITYCheck each switch for continuity with the poc-ket tester. If the continuity reading is incorrect,check the wiring connections and if necessary,replace the switch.

CAUTION:

Never insert the tester probes into the cou-pler terminal slots. Always insert the probesfrom the opposite end of the coupler, takingcare not to loosen or damage the leads.

NOTE:

• Before checking for continuity, set the poc-ket tester to “0” and to the “Ωx1” range.

• When checking for continuity, switch backand forth between the switch positions afew times.

The terminal connections for switches (e.g.,main switch, engine stop switch) are shown inan illustration similar to the one on the left.The switch positions a are shown in the farleft column and the switch lead colors b areshown in the top row in the switch illustration.

NOTE:

“—” indicates a continuity of electricitybetween switch terminals (i.e., a closed circuitat the respective switch position).

The example illustration on the left showsthat:There is continuity between black andblack/white when the switch is set to “ON”.There is continuity between red and brownwhen the switch is set to “ON”.


ELECCHECKING THE SWITCHES

8-5

EAS00731

CHECKING THE SWITCHESCheck each switch for damage or wear, properconnections, and also for continuity between theterminals. Refer to “CHECKING SWITCH CON-TINUITY”.

Damage/wear Repair or replace.Improperly connected Properly connect.Incorrect continuity reading Replace theswitch.

7

20

20

22

23

12

9

10

35

1528

Main swich 35 Oil Level gauge24 Left handle swicht 15 Neutral swicht12 Side stand swicht 28 Rear stop swicht Right handle swicht Fuse

ELECIGNITION SYSTEM

8-6

IGNITION SYSTEMThe circuit diagram showns the ignition system.

ELECIGNITION SYSTEM

8-7

NOTE:

For the color codes see the electric diagram

Magneto CDI Battery Fuse Starter relay Starting engine Main switch C.D.I. Ignition coil

7

5

·

8

·

9

4 2

6

1

ELECIGNITION SYSTEM

8-8

EAS00736

TROUBLESHOOTING

Check:1. Main and ignition fuses2. Battery3. Spark plug4. Ignition spark gap5. Spark plug cap resistance6. Ignition coil resistance7. Main switch8. Engine stop switch9. Neutral switch10. Sidestand switch11. Pickup coil resistance12. Wiring connections (of the entire ignition

system)

NOTE:

• Before troubleshooting, remove the follo-wing part(s):1. Side covers (right and left)2. Seat3. Fuel tank4. Headlight cover5. Headlight unit

• Troubleshoot with the following specialtool(s).

The ignition system fails to operate(no spark or intermittent spark).

EAS00740

1. Spark plug

• Check the condition of the spark plug.• Check the spark plug type.• Measure the spark plug gap.

Refer to “CHECKING THE SPARK PLUG”in chapter 3.

Standard spark plugBR8HS (NGK)

Spark plug gap0.6 ~ 0.7 mm

• Is the spark plug in good condition, is it ofthe correct type, and is its gap within spe-cification?

EAS00742

2. Ignition spark gap

• Disconnect the spark plug cap from thespark plug.

• Connect the ignition checker as shown.

Spark plug cap• Set the main switch to “ON”.• Measure the ignition spark gap a .• Crank the engine by pushing the starter

switch and gradually increase the sparkgap until a misfire occurs.

Minimum ignition spark gap6 mm (0.24 in)

• Is there a spark and is the spark gap withinspecification?

Ignition checker90890-06754


YES NO

Re-gap or replacethe spark plug.

The ignition systemis OK.

YES NO

ELECIGNITION SYSTEM

8-9

• Connect the pocket tester (Ω x 1k) to the ignition coil as shown.

Negative tester probe Ignition coil base Positive tester probe spark plug lead

• Measure the secondary coil resistance.

Secondary coil resistance7.9 +/- kΩ 20°C (68 °C)

• Is the ignition coil OK?

EAS00744

3. Spark plug cap resistance

• Remove the spark plug cap from the sparkplug lead.

• Connect the pocket tester (“Ω x 1k” range)to the spark plug cap as shown.

• Measure the spark plug cap resistance.

Spark plug cap resistance5KΩ at 20°C (68 °C)

• Is the spark plug cap OK?

EAS00746

4. Ignition coil resistance (Orange) from thewireharness

• Disconnect the ignition coil connectorsfrom the ignition coil terminals.

• Connect the pocket tester (Ω x 1) to theignition coil as shown.

Positive tester probe Orange terminalNegative tester probe Ignition coilbase

• Measure the primary coil resistance.

Primary coil resistance0.23 +/- 20°C (68 °C)

Replace the sparkplug cap.

Replace the ignitioncoil.

YES NOYES NO

ELECIGNITION SYSTEM

8-10

EAS00749

5. Main switch

• Disconnect the main switch coupler andlead from the wireharness (red).

• Connect the pocket tester (Ω 100) to themain switch.

Positive tester probe red Lead

Negative tester probe brown-blueTerminal

• Turn the main switch to “ON” and “OFF”.• Check the main switch for continuity.

Switch Good Badposition condition condition

OFF X X ON X X

PARK X X

:Continuity X: No continuity

EAS00750

6. “ENGINE STOP” switch

• Disconnect the “ENGINE STOP” switchleads from the wireharness.

• Connect the pocket tester (Ω 100) to the“ENGINE STOP” switch.

Positive tester probe black/white Lead

Negative tester probe Black Lead

• Turn the “ENGINE STOP” switch to “OFF”and “RUN”.

• Check the “ENGINE STOP” switch for con-tinuity.


OFF X X ON X X


• Is the engine stop switch OK?

Replace the mainswitch.

YES NO

Replace the hand-lebar switch.

YES NO

ELECIGNITION SYSTEM

8-11

7. source coil resistance

• Disconnect the CDI magneto coupler from the wireharness.

• Connect the pocket tester (Ω 100) to thesource coil.

Positive tester probe Green/white TerminalNegative tester probe Black/red Teminal

• Measure the source coil resistance.

Source coil resistance192~288 Ω at 20°C (68°F)

• Is the source coil resistance OK?

Replace the sourcecoil.

YES NO

EAS00748

8. Pickup coil resistance

• Disconnect the CDI magneto coupler fromthe wire harness.

• Connect the pocket tester (Ω 100) to thepickup coil.

Positive tester probe white/blueNegative tester probe white/red

• Measure the pickup coil resistance.

Pickup coil resistance280 ~ 420 Ω at 20°C (68°F)(between white/red andwhite/blue)

• Is the pickup coil OK?

EAS00754

9. Wiring

• Check the entire ignition system’s wiring.Refer to “CIRCUIT DIAGRAM”.

• Is the ignition system’s wiring properly con-nected and without defects?

Replace the pickupcoil.

YES NO

Properly connect orrepair the ignitionsystem’s wiring.

Replace the DC-CDI unit.

YES NO

2

1

3 2

3

1

ELECIGNITION SYSTEM

8-12

EAS00752

Procedure (2)

1. Sidestand switch

• Disconnect the sidestand switch leadsfrom the wireharness.

• Connect the pocket tester (Ω100) to thesidestand switch.

Positive tester probe blue/whiteTerminalNegative tester probe blue/blackTerminal

• Move the sidestand to up position anddown position.

• Check the sidestand switch for continuity.


UP X X DOWN X X


• Is the sidestand switch OK?

Replace the sides-tand switch.

YES NO

EAS00751

2. Neutral switch

• Disconnect the CDI magneto coupler fromthe wireharness.• Connect the pocket tester (Ω 100) to theneutral switch lead.

Positive tester probe sky blue leadNegative tester probe Frame ground

• Shift the transmission in neutral and gear.• Check the neutral switch for continuity.


NEUTRAL X X GEAR X X


• Is the sidestand switch OK?

EAS00754

3. Wiring

• Check the entire ignition system’s wiring.Refer to “CIRCUIT DIAGRAM”.

• Is the ignition system’s wiring properly con-nected and without defects?

Replace the sides-tand switch.

YES NO

Properly connect orrepair the ignitionsystem’s wiring.

Replace the DC-CDI unit.

YES NO

1

2

ELECCHARGING SYSTEM

8-14

EAS00773

CHARGING SYSTEMCIRCUIT DIAGRAM

Generator Rectifier/regulator

Battery Main fuse

ELECCHARGING SYSTEM

8-15

EAS00774

TROUBLESHOOTING

1. main fuse2. battery3. charging voltage4. charging coil resistance5. wiring connections

(of the entire charging system)

NOTE:

• Before troubleshooting, remove the follo-wing part(s):1. Side covers (Left and right)2. Seat3. Fuel tank4. Radiator cover


1. Fuse

• Remove the fuse.• Connect the pocket tester (Ω 100) to the

fuse. • Check the fuse for continuity.• Is the fuse OK?

2. Battery

• Check the battery condition.Refer to the “BATTERY INSPECTION” sec-tion in CHAPTER 3.

• Is the battery OK?

The battery is not being charged.

EAS00775

3. Charging voltage

• Connect the engine tachometer to thespark plug lead.

• Connect the pocket tester (DC 20 V) to thebattery.

Positive tester probe positive batteryterminalNegative tester probe negative batteryterminal

• Start the engine and let it run at approxi-mately 3000 r/min.

• Measure the charging voltage.

Charging voltage14 V at 5000 r/min

NOTE:

Make sure the battery is fully charged.

• Is the charging voltage within specification?

EAS00779

4. Wiring

• Check the wiring connections of the entirecharging system.Refer to “CIRCUIT DIAGRAM”.

• Is the charging system’s wiring properlyconnected and without defects?

Engine tachometer90890-03113


Replace the fuse.

YES NO

Replace the battery.

YES NO

The charging circuitis OK.

YES NO

Properly connect orrepair the chargingsystem’s wiring.

Replace the recti-fier/regulator.

YES NO

ELECLIGHTING SYSTEM

8-16

EAS00780

LIGHTING SYSTEMCIRCUIT DIAGRAM

Magento-CDI Rectifier/regulator Main switch21 “LIGHTS” switch

29 Headlight34 Tail light36 Meter lights

ELECLIGHTING SYSTEM

8-17

EAS00781

TROUBLESHOOTING

Check:1. Headlight bulb/”HI BEAM” indicator light

bulb2. Headlight bulb socket/”HI BEAM”3. “LIGHTS” (dimmer) switch4. “Lights” switch5. Lighting voltage6. Lighting coil resistance7. wiring connection

(of the entire lighting system)

NOTE:

• Before troubleshooting, remove the follo-wing part(s):1. Sidecovers (left and right)2. Seat3. Fuel tank4. Headlight cover5. Headlight unit


Any of the following fail to light: head-light, high beam indicator light, taillight,

auxiliary light or meter light.

1. Bulb

• Remove the bulb.Refer to the “HEADLIGHT BULB REPLA-CEMENT” section in the chapter 3.

• Connect the pocket tester (Ω 100) to thebulbs terminals.

Positive tester probe terminal Negative tester probe terminal


A. Headlight bulbB. “HI BEAM” indicator light bulb

• Check the bulb for continuity.• Is the bulb OK?


Inductive Tachometer:90890-03113

Replace the bulb.

YES NO

A

B

ELECLIGHTING SYSTEM

8-18

2. Bulb socket

• Disconnect the bulb socket leads from thewire harness.

• Install the bulb to the bulb socket.• Connect the pocket tester (Ω 100) to the

bulbs terminals.

Positive tester probe Yellow leadNegative tester probe Black lead

Positive tester probe Green leadNegative tester probe Black lead

A. Headlight bulb socketB. “HI BEAM” indicator light bulb socket

• Check the bulb socket for continuity.• Is the bulb socket OK?

3. “LIGHTS” (Dimmer) switch


When turning “LIGHTS” (Dimmer) switch to“HI”.

Positive tester probe Yellow leadNegative tester probe Black lead

When turning “LIGHTS” (Dimmer) switch to“LO”.

Positive tester probe Green leadNegative tester probe Black lead

• Turn the “LIGHTS” (Dimmer) switch to the“HI” and “LO”.

• Check the “LIGHTS” (Dimmer) for conti-nuity.


“HI” X X“LO” X X


• Is the “LIGHTS” (Dimmer) OK?

Replace the bulbsocket.

YES NO

Replace handlebarswitch (left).

YES NO

ELECLIGHTING SYSTEM

8-19

4. Lighting voltage.

• Turn (Dimmer) switch to “LO”.• Connect the pocket tester (DC 20 V) to the

battery.

Positive tester probe Green terminalNegative tester probe Black terminal

• Connect the inductive tachometer to thespark plug lead.

• Start the engine and check the lightningvoltage.

• Is the “LIGHTS” switch OK?

EAS00787

5. Wiring

• Check the entire lighting system’s wiring.Refer to “CIRCUIT DIAGRAM”.

• Is the lighting system’s wiring properly con-nected and without defects?

Replace handlebarswitch (left).

YES NO

Properly connect orrepair the lightingsystem’s wiring.

Check the conditionof each of the ligh-ting system’s cir-cuits.Refer to “CHEC-KING THE LIGH-TING SYSTEM”.

YES NO

ELECLIGHTING SYSTEM

8-20

TROUBLESHOOTING

Check:1. Meter light bulb2. Meter light bulb socket3. Wiring connection


NOTE:



Meter light does not come on1. Bulb

• Remove the bulb.Refer to the “METER ASSEMBLY” section.






Replace the bulb.

YES NO

ELECLIGHTING SYSTEM

8-21

2. Bulb socket

• Disconnect the bulb socket lead and cou-pler from the wire harness.


bulbs socket lead end and coupler.

Positive tester probe Blue leadNegative tester probe Black Terminal


EAS00787

3. Wiring




YES NO



YES NO

ELECLIGHTING SYSTEM

8-22

TROUBLESHOOTING

Check:1. Tail/Brake light bulb/Auxiliary light bulb2. Tail light bulb socket/Auxiliary light3. Main switch4. Wiring connection


NOTE:



Tail light/Auxiliary light do not come on1. Bulb

• Remove the bulb.• Connect the pocket tester (Ω 1) to the bulb

terminals.



A. Tail/Brake bulbB. Auxiliary light bulb




Replace the bulb.

YES NO

ELECLIGHTING SYSTEM

8-23

2. Bulb socket

• Disconnect the bulb socket and leads fromthe wire harness.


bulbs socket lead end and coupler.

APositive tester probe Blue TerminalNegative tester probe Black Terminal

BPositive tester probe Blue/Red LeadNegative tester probe Black Lead


3. Main switch

• Disconnect the main switch coupler fromthe wire harness.

• Connect the pocket tester (Ω 1) to the mainswitch.

• Check the main switch for continuity.

APositive tester probe Red LeadNegative tester probe Brown-blueLead


ON X X OFF X X

BPositive tester probe Yellow-blue LeadNegative tester probe Blue-BlackLead


ON X X OFF X X

CPositive tester probe Red LeadNegative tester probe Blue-BlackLead


P X X OFF X X



YES NO

A

B

ELECLIGHTING SYSTEM

8-24

EAS00787

4. Wiring





YES NO

ELECSIGNAL SYSTEM

8-26

EAS00793

SIGNALING SYSTEMCIRCUIT DIAGRAM

Main switch Main fuse Battery15 Neutral switch35 Engine oil level switch

37 Diode20 Horn switch25 Horn 22 Turn switch26 Turn signal relay

34 Tail/brake light28 Rear brake light switch27 Front brake light switch

ELECSIGNAL SYSTEM

8-27

EAS00794

TROUBLESHOOTING

Check:1. Fuse2. battery3. main switch4. wiring connections

(of the entire signaling system)

NOTE:

• Before troubleshooting, remove the follo-wing part(s):1. Side covers (left and right)2. Seat3. Fuel tank4. Headlight cover5. Headlight unit


1. Fuse

• Remove the fuse.• Connect the pocket tester (Ω 1) to the fuse.• Check the fuse for continuity.

2. Battery

• Check the battery condition.Refer to the “BATTERY INSPECTION” sec-tion in chapter 3.

Any of the following fail to light: flasherlight, brake light or an indicator light donot come on and the horn fails to sound.

3. Main switch



Tester (+) Lead Red LeadTeter (-) Lead Brown-Blue Lead

• Turn the main switch to “ON”, “OFF” and“PARK”.



ON X X OFF X X

PARK X X


EAS00795

4. Wiring

• Check the entire signal system’s wiring.Refer to “CIRCUIT DIAGRAM”.

• Is the signaling system’s wiring properlyconnected and without defects?


Properly connect orrepair the signalingsystem’s wiring.

Check the conditionof each of the sig-naling system’s cir-cuits.Refer to “CHEC-KING THE SIGNA-LING SYSTEM”.

YES NO

ELECSIGNAL SYSTEM

8-28

1. Bulb


terminals.


• Check the bulb for continuity.

FLASHER LIGHT DOES NOT BRINK2. Bulb socket

• Install the bulb to the sockets.• Disconnect the flahser light leads from

the wire harness.• Connect the pocket tester (Ω 1) to the flas-

her light leads.

When checking right flasher light:Positive tester probe Dark Green LeadNegative tester probe Black Lead

When checking left flasher light:Positive tester probe Chocolate LeadNegative tester probe Black Lead


Replace the bulb

YES NO


YES NO

A

B

FRONT

REAR

ELECSIGNAL SYSTEM

8-29

3. “TURN” switch

• Disconnect the “TURN” switch (Left hand-lebar switch) coupler from the wire har-ness.

• Connect the pocket tester (Ω 1) to the“TURN” switch.

When turning “TURN”” switch to “R”:Positive tester probe Brown/White LeadNegative tester probe Dark green Lead

When turning “TURN” switch to “L”:Positive tester probe Brown/White LeadNegative tester probe Chocolate Lead

• Turn the “TURN” switch to the “R” and “L”.• Check the “TURN” switch for continuity.


R X X L X X


• Is the “TURN” switch OK?

4. Voltage

• Disconnect the flasher relay couplerfrom the wire harness.

• Turn the main switch to “ON”.• Turn the “TURN” switch to the “R” or “L”.• Connect the pocket tester (DC20V) to the

flasher relay coupler.

Positive tester probe Brown TerminalNegative tester probe Frame ground.

• Check the flasher votage.

Flasher voltage12.0 V

• Is the flasher relay OK?

EAS00795

5. Wiring



Replace the“TURN” switch.

YES NO

Replace the flasherrelay.

YES NO



YES NO

ELECSIGNAL SYSTEM

8-30

1. Bulb


terminals.



BRAKE LIGH DOES NOT COME ON2. Bulb socket

• Disconnect the bulb socket coupler from the wire harness.

• Connect the pocket tester (Ω 1) to the bulbsocket leads.

Positive tester probe Yellow TerminalNegative tester probe Black Terminal


Replace the bulb

YES NOReplace the bulbsocket.

YES NO

ELECSIGNAL SYSTEM

8-31

3. Front brake switch

• Disconnect the front brake switch coupler from the wire harness.

• Connect the pocket tester (Ω 1) to thebrake switch coupler.

Positive tester probe Brown TerminalNegative tester probe Green/YellowTerminal

• Check the brake switch for continuity.


Front brake X X appliedFront brake X X not applied


• Is the front brake switch OK?

4. Rear brake switch

• Disconnect the front brake switch coupler from the wire harness.

• Connect the pocket tester (Ω 1) to thebrake switch coupler.

Positive tester probe Brown TerminalNegative tester probe Green/Yellow Terminal

• Check the brake switch for continuity.


Rear brake X X appliedRear brake X X not applied


• Is the rear brake switch OK?

EAS00795

5. Wiring



Replace the frontbrake switch.

YES NO

Replace the rearbrake switch.

YES NO


Check the condition ofeach of the signalingsystem’s circuits. Referto “CHECKING THESIGNALING SYSTEM”.

YES NO

ELECSIGNAL SYSTEM

8-32

1. Bulb


• Connect the pocket tester (Ω 1) to the bulbterminals.



“NEUTRAL” INDICATOR LIGHT DOESNOT COME ON

2. Bulb socket

• Disconnect the bulb socket coupler fromthe wire harness.

• Connect the pocket tester (Ω 1) to the bulbsocket leads.

Positive tester probe Brown TerminalNegative tester probe Sky Blue Terminal


Replace the bulb.

YES NOReplace the bulbsocket.

YES NO

ELECSIGNAL SYSTEM

8-33

3. Neutral switch

• Disconnect the CDI magneto coupler fromthe wire harness.

• Connect the pocket tester (Ω 1) to the neu-tral switch coupler.

Positive tester probe Sky BlueTerminalNegative tester probe Frame ground

• Shift the transmission in neutral and gear.• Check the neutral switch for continuity.


Neutral X X Gear X X


• Is the neutral switch OK?

EAS00795

4. Wiring



Replace the neutralswitch.

YES NO



YES NO

ELECSIGNAL SYSTEM

8-34

1. Bulb


• Connect the pocket tester (Ω 1) to the bulbterminals.



“OIL” INDICATOR LIGHT DOES NOTCOME ON

2. Bulb socket

• Disconnect the bulb socket coupler from the wire harness.

• Connect the pocket tester (Ω 1) to the cou-pler.

Positive tester probe Brown TerminalNegative tester probe Black/Red Terminal


Replace the bulb.

YES NO Replace the bulbsocket.

YES NO

ELECSIGNAL SYSTEM

8-35

3. Oil level switch (Diode)

• Disconnect the oil level switch from thewire harness.

• Connect the pocket tester (Ω 1) to the neu-tral switch coupler.

Positive tester probe Black/Red TerminalNegative tester probe Sky Blue Terminal

• Check the oil level switch for continuity.

• Is the oil level switch OK?

4. Oil level switch

• Connect the pocket tester (Ω 1) to the oillevel switch.

Positive tester probe Black/Red TerminalNegative tester probe Black Terminal

• Hold the oil level switch in an upright andupside down position.

• Check the oil level switch for continuity.


Upright X X Upside X X



EAS00795

5. Wiring



Replace the oil levelswitch.

YES NO

Replace the oil levelswitch.

YES NO



YES NO

ELECSIGNAL SYSTEM

8-36

1. “HORN” switch

• Disconnect the “HORN” switch (Left hand-lebar switch) couplers from the wire har-ness.

• Connect the pocket tester (Ω 1) to the“HORN” switch.

Positive tester probe Pink TerminalNegative tester probe Black Terminal

• Check the “HORN” switch for continuity.


“HORN” switch X X is pushed“HORN” switch X X is not pushed



HORN DOES NOT SOUND, WHEN PUS-HING “HORN” SWITCH

2. Voltage

• Connect the pocket tester (DC20V) to thehorn terminal.

Positive tester probe Brown TerminalNegative tester probe Frame ground.

• Turn the main switch to “ON”.• Check the horn voltage.

Horn voltage12.0 V

EAS00795

3. Wiring



Replace the“HORN” switch.

YES NOProperly connect orrepair the signalingsystem’s wiring.


YES NO

ELECSIGNAL SYSTEM

8-37

4. Horn

• Disconnect the “pink” lead at the horn ter-minal.

• Connect a jumper lead to the horn ter-minal and ground the jumper lead.

• Does the horn sounds OK?

5. Voltage

• Connect the pocket tester (DC20V) to thehorn at the pink terminal.

Positive tester probe Pink TerminalNegative tester probe Frame ground.

• Check the “pink” terminal voltage.

“Pink” terminal voltage12.0 V

Replace the horn.

YES NO

ELECCOOLING SYSTEM

8-38

EAS00807

COOLING SYSTEMCIRCUIT DIAGRAM

Battery Main switch

Main fuse13 Thermo switch

ELECCOOLING SYSTEM

8-39

EAS00808

TROUBLESHOOTING

Check:1. main fuse2. battery3. main switch4. thermo switch5. wiring connections

(the entire cooling system)

NOTE:

• Before troubleshooting, remove the follo-wing part(s):1. side covers (left and right)2. seat3. fuel tank4. headlight cover5. headlight unit


• The radiator fan motor fails to turn.• The water temperature gauge needle

fails to move when the engine is warm.

1. Fuse

• Remove the fuse.• Connect the pocket tester (Ω 1) to the fuse.• Check the fuse for continuity.• Is the fuse OK?

2. Battery



Replace the fuse.

YES NO

ELECCOOLING SYSTEM

8-40

3. Main switch



Positive tester probe Red LeadNegative tester probe Brown-BlueTerminal

• Turn the main switch to “ON”, “OFF” and“PARK”.• Check the main switch for continuity.


ON X X OFF X X

PARK X X


4. Thermo unit

• Remove the thermo unit from the cylinderhead.

• Connect the pocket tester (Ω 1) to the ther-mo unit

• Inmerse the thermo unit in the water • Measure the resistances.Note temperatures while heating the waterwith the temperature gauge

Positive tester probe Terminal Negative tester probe Body ground

Water 50ºC 80ºC 100ºCtemperature (122ºF) (176ºF) (212ºF)

Resistance 153.9Ω 47.5~56.8Ω 26.2~29.3Ω

• Is the thermo unit OK?


YES NOReplace the thermounit.

YES NO

ELECCOOLING SYSTEM

8-41

EAS00795

5. Wiring





YES NO

ELECYAMAHA POWER VALVE SYSTEM

8-42

YAMAHA POWER VALVE SYSTEMCIRCUIT DIAGRAM

16 CDI Unit Main switch Main fuse

Battery18 Servomotor

ELECMOTOR

8-43

TROUBLESHOOTING

Check:1. fuse2. battery3. main switch4. servomotor operation5. wiring connections (Yamaha Power Valve

System)6. servomotor and tachometer operation

NOTE:

• Before troubleshooting, remove the follo-wing part(s):1. side covers (left and right)2. seat3. fuel tank4. headlight cover5. headlight unit


Servomotor does not move

1. Fuse

• Remove the fuse.• Connect the pocket tester (Ω 1) to the fuse.• Check the fuse for continuity.• Is the fuse OK?

2. Battery



Replace the fuse.

YES NO

ELECMOTOR

8-44

3. Main switch

• Disconnect the main switch coupler from the wire harness.


Positive tester probe Red LeadNegative tester probe Brown-Blue Terminal

• Turn the main switch to “ON”, “OFF” and“PARK”.



ON X X OFF X X

PARK X X


4. Servomotor operation

• Disconnect servomotor coupler from thewire harness.

• Connect the battery leads to the servomo-tor.

Positive tester probe Brown TerminalNegative tester probe Black Terminal

• Check the servomotor for operation.• Is the servomotor OK?

EAS00795

5. Wiring




YES NO

Replace the servo-motor.

YES NO



YES NO

ELECMOTOR

8-45

6. Servomotor and tachometer operation

• Start the engine and increase revolution toabout 7000rev/min.

• Check servomotor and tachometer foroperation.


• Is the servomotor OK?

Replace the servo-motor.

YES NO

ELECMETER ASSEMBLY

8-46

METER ASSEMBLY

Speedometer Bulb Bulb socket Speedometer cable Meter cushion

Meter bracket Stopper clip Washer Damper collar

ELECMETER ASSEMBLY

8-47

REMOVAL1. Remove:• Headlight cover

2. Disconnect:• Headlight leads• Auxiliary light leads

3. Remove:• Band

4. Disconnect:• Speedometer cable

5. Disconnect:• Meter leads

6. Remove:• Meter assembly

1

1

ELECMETER ASSEMBLY

8-48

7. Remove:• Meter cushion • Meter lights • Leads

CAUTION

Do not remove the indicator bulbs socketsby pulling the leads

INSTALLATIONReverse the “REMOVAL” procedure. Note thefollowing points:1. Install the meter lights, indicator lights and

leads as shown.

”OIL” indicator light ”NEUTRAL” indicator light ”HIGH BEAM” indicator light ”TURN” indicator light

2. Install:• Meter assembly

Bolt (Meter Assembly)7 Nm (0.7 m•kg, 5.1 ft•lb)

3

2

4

1

3

1

2

ELECMETER ASSEMBLY

8-49

NOTE:

Install the headlight lens unit onto the head-light stay by fitting the guide rubber pro-perly in the guide hole of the headlight unit.

3. Install:• Headlight cover

4. Adjust:• Headlight beamRefer to the “HEADLIGHT BEAM ADJUST-MENT” section.

1

TRBLSHTG

?

9?

CHAPTER 9TROUBLESHOOTING

STARTING FAILURE / HARD STARTING ……………………………………9-1FUEL SYSTEM …………………………………………………………………9-1ELECTRICAL SYSTEM ………………………………………………………9-2

POOR IDLE SPEED PERFORMANCE ………………………………………9-3POOR IDLE SPEED PERFORMANCE ………………………………………9-3

POOR MEDIUM AND HIGH SPEED PERFORMANCE ……………………9-3FUEL SYSTEM …………………………………………………………………9-3ELECTRICAL SYSTEM ………………………………………………………9-3COMPRESSION SYSTEM ……………………………………………………9-4Y.P.V.S. …………………………………………………………………………9-4

FAULTY GEAR SHIFTING ………………………………………………………9-5HARD SHIFTING ………………………………………………………………9-5CHANGE PEDAL DOES NOT MOVE ………………………………………9-5JUMP OUT GEAR ……………………………………………………………9-5

CLUTCH SLIPPING/DRAGGING ………………………………………………9-5CLUTCH SLIPPING ……………………………………………………………9-5CLUTCH DRAGGING …………………………………………………………9-6

FAULTY BRAKE …………………………………………………………………9-6POOR BRAKING EFFECT ……………………………………………………9-6

FRONT FORK OIL LEAKAGE AND FRONT FORK MALFUNCTION ……9-6OIL LEAKAGE …………………………………………………………………9-6MALFUNCTION ………………………………………………………………9-6

INSTABLE HANDLING …………………………………………………………9-7INSTABLE HANDLING ………………………………………………………9-7

FAULTY SIGNAL AND LIGHTING SYSTEM …………………………………9-8HEADLIGHT DARK ……………………………………………………………9-8BULB BURNT OUT ……………………………………………………………9-8FLASHER DOES NOT LIGHT ………………………………………………9-8FLASHER KEEPS ON …………………………………………………………9-8FLASHER WINKS SLOWER …………………………………………………9-8FLASHER WINKS QUICKER …………………………………………………9-8HORN IS INOPERATIVE ………………………………………………………9-8

FAULTY Y.P.V.S. …………………………………………………………………9-9FAULTY Y.P.V.S …………………………………………………………………9-9

OVERHEATING OR OVERCOOLING …………………………………………9-9OVERHEATING…………………………………………………………………9-9OVERCOOLING ………………………………………………………………9-9

DT125 WIRING DIAGRAM ……………………………………………………9-10

TRBLSHTG

TROUBLESHOOTING

NOTE:

The following troubleshooting does not cover all the possible causes of trouble. It should be help-ful, however, as a guide to troubleshooting. Refeer to the relative procedure in this manual for ins-pection, adjustment and replacement of parts.

STARTING FAILURE/HARD STARTING

FUEL SYSTEM PROBABLE CAUSE

• Fuel tank • Empty• Clogged fuel filter• Clogged fuel tank cap• Deteriorated fuel or fuel containingor foreign material

• Fuel cock • Clogged fuel hose

• Carburetor • Deteriorated fuel, fuel containing water or foreign material• Clogged pilot jet• Clogged pilot air passage• Sucked-in air• Deformed float• Groove worm needle valve• Improperly sealed valve seat• Improperly adjustment fuel level• Improperly set pilot jet• Clogged starter jet• Starter plunger malfunction• Improperly adjusted starter cable

• Air cleaner • Clogged air filter

STARTING FAILURE/HARD STARTINGTRBLSHTG

9-1

ELECTRICAL SYSTEM PROBABLE CAUSE

• Spark plug • Improper plug gap• Worn electrodes• Wire between terminals broken• Improper heat range• Faulty spark plug cap

• Ignition coil • Broken or shorted primary/secondary• Faulty spark plug lead• Broken body

• C.D.I. Unit system • Faulty C.D.I. unit• Faulty source coil• Faulty pick-up coil• Broken woodruff key

• Switches and wiring • Faulty main switch• Faulty engine stop switch• Broken or shorted wiring• Faulty neutral switch• Faulty sidestand switch• Faulty ignition control unit

COMPRESSION SYSTEM PROBABLE CAUSE

• Cylinder and cylinder head • Loose spark plug• Loose cylinder head or cylinder• Broken cylinder head gasket• Broken cylinder gasket• Worn, damaged or seized cylinder

• Piston and piston rings • Improperly installed piston ring• Worn, fatigued or broken piston ring• Seized piston ring• Seized or damaged piston

• Crankcase and crankshaft • Improperly seated crankcase• Improperly sealed crankcase

(Damaged oil seal)• Seized crankshaft

• Reed valve • Deformed reed valve stopper• Improperly seated reed valve• Loose intake manifold• Broken gasket• Broken reed valve

9-2

TRBLSHTGTROUBLESHOOTING

POOR IDLE SPEED PERFORMANCE

POOR IDLE SPEED PERFORMANCE PROBABLE CAUSE• Carburetor • Improperly returned starter plunger

• Clogged or loose pilot jet• Clogged pilot air passage• Improperly adjusted idle speed

(throttle stop screw)• Improper throttle cable play• Faulty pick up coil

POOR MEDIUM AND HIGH SPEED PERFORMANCE

FUEL SYSTEM PROBLABLE CAUSE

• Fuel tank • Clogged fuel filter • Deteriorated fuel or fuel containing

water or foreign material• Clogged fuel breather hose

• Fuel cock • Clogged fuel hose

• Carburetor • Deteriorated fuel or fuel containingwater or foreign material

• Sucked-in air• Deformed float• Groove worn needle valve• Improperly sealed valve seat• Improperly set clip position of jet needle• Improperly adjusted fuel level• Clogged or loose main jet• Clogged or loose needle jet

• Air cleaner • Clogged air filter

ELECTRICAL SYSTEM PROBLABLE CAUSE

• Spark plug • Improper plug gap• Worn electrodes• Wire between terminals broken• Improper heat range• Faulty spark plug cap

• CDI unit system • Faulty CDI unit• Faulty source coil• Faulty pickup coil

9-3


COMPRESSION SYSTEM PROBABLE CAUSE

• Cylinder and cylinder head • Loose spark plug• Broken cylinder head gasket• Broken cylinder gasket• Loose cylinder head or cylinder• Worn, damaged or seized cylinder

• Piston and piston ring • Improperly installed piston ring• Worn, fatigued or broken piston ring• Seized piston ring• Seized or damaged piston

• Crankcase and crankshaft • Improperly seated crankcase• Improperly sealed crankcase

(Damaged oil seal)• Seized crankshaft

• Reed valve • Deformed reed valve stopper• Improperly adjusted reed valve stopper

height• Improperly seated reed valve• Loose intake manifold• Broken gasket• Broken reed valve

Y.P.V.S. PROBABLE CAUSE

• Power valve • Seized or damaged power valve• Carbon buid-up

• Control cable • Improperly adjustable cable• Seized or discontinuous cable

• Electrical parts • Faulty battery(Improperly charged battery)

• Faulty main switch• Faulty servomotor• Faulty GDI unit• Faulty Y.P.V.S. control unit• Broken or shorted wiring

9-4


FAULTY GEAR SHIFTING

HARD SHIFTING PROBABLE CAUSE

• Clutch • Improperly adjusted clutch cable• Improperly adjusted push lever position• Improper engagement of push lever and

push rod• Warped clutch plate• Swollen friction plate• Broken clutch plate

• Transmission oil • High oil level• Improper quality (High viscosity)• Deterioration

CHANGE PEDAL DOES NOT MOVE PROBABLE CAUSE

• Shift shaft • Bent shift shaft

• Shift cam and shift fork • Groove jammed with impurities• Seized shift fork• Bent shift forks guide bar

• Transmission • Seized transmission gear• Jammed impurities• Incorrectly assembled transmission

JUMP OUT GEAR PROBABLE CAUSE

• Shift shaft • Improperly adjusted shift lever position• Improperly returned stopper lever

•Shift fork • Worn shift fork

• Shift cam • Improper thrust play• Worn shift cam groove

• Transmission • Worn gear dog

CLUTCH SLIPPING/DRAGGING

CLUTCH SLIPPING PROBABLE CAUSE• Clutch • Improperly adjusted clutch cable

• Loose clutch spring• Fatigued clutch sping• Worn friction plate• Worn clutch plate

• Transmission • Low oil level• Improper quality (Low viscosity)• Deterioration

9-5


CLUTCH DRAGGING PROBABLE CAUSE• Clutch • Improperly adjusted clutch cable

• Improperly adjusted push lever position• Improper engagement of push lever and

push rod• Warped clutch plate• Swollen friction plate • Broken clutch boss

• Transmission oil • High oil level • Improper quality (High viscosity)• Deterioration

FAULTY BRAKE

POOR BRAKING EFFECT PROBABLE CAUSE

• Disc brake • Worn brake pad• Worn brake disc• Air in brake fluid• Leaking brake fluid• Faulty cylinder kit cup• Faulty caliper kit seal• Loose union bolt• Broken brake hose• Oily or grasy brake disc• Oily or greasy brake pad• Improper brake fluid level

FRONT FORK OIL LEAKAGE AND FRONT FORK MALFUNCTION

OIL LEAKAGE PROBABLE CAUSE• Bent, damaged or rusty inner tube• Damaged or cracked outer tube• Damaged oil seal lip• Improperly installed oil seal• Improper oil level (too much)• Loose damper rod holding bolt• Broken

MALFUNCTION• Bent, deformed or damaged inner tube• Bent or deformed outer tube• Damaged fork spring• Worn or damaged slide metal• Bent or damaged damper rod• Improper oil viscosity• Improper oil level

9-6


INSTABLE HANDLINGINSTABLE HANDLING PROBABLE CAUSE

• Handlebars • Improperly installed or bent

• Steering • Improperly installed handle crown• Bent steering shaft• Improperly installed steering shaft

(Improperly tightened ringnut)• Damaged ball bearing

(roller bearing or bearing race)

• Front forks • Uneven oil levels on both sides• Uneven spring tension

(Uneven damping adjuster position)• Broken spring• Twisted front forks

• Tires • Uneven tire pressure on both sides• Incorrect tire pressure• Unevenly worn tires

• Wheels • Incorrect wheel balance• Deformed cast wheel• Loose bearing• Bent or loose wheel axle• Excessive wheel run-out

• Frame • Twisted• Damaged head pipe• Improperly installed bearing race

• Swingarm • Worn bearing or bush• Bent or damaged

• Rear shock absorber • Fatigued spring• Improperly adjusted spring preload• Oil leakage

• Drive chain • Improperly adjusted chain slack

9-7


FAULTY SIGNAL AND LIGHTING SYSTEM

HEADLIGHT DARK PROBABLE CAUSE• Improper bulb• Too many electric accesories• Hard charging (Broken charging coil

and/or faulty rectifier/regualtor)• Incorrect connection• Improperly grounded• Poor contacts (main or “LIGHTS”

switch)• Bulb life expired

BULB BURNT OUT PROBABLE CAUSE• Improper bulb• Faulty battery• Faulty rectifier/regulator• Improperly grounded• Faulty main and/or light switch• Bulb life expired

FLASHER DOES NOT LIGHT PROBABLE CAUSE• Improperly grounded• Discharged battery• Faulty “TURN” switch• Faulty flasher relay• Broken wireharness• Loosely connected coupler• Bulb burnt out

FLASHER KEEPS ON PROBABLE CAUSE• Faulty flasher relay• Insufficient battery capacity

(nearly discharged)• Bulb burnt out

FLASHER WINKS SLOWER PROBABLE CAUSE• Faulty flasher relay• Insufficient battery capacity

(nearly discharged)• Improper bulb• Faulty main and/or “TURN” switch

FLASHER WINKS QUICKER PROBABLE CAUSE• Improper bulb• Faulty flasher relay

HORN IS INOPERATIVE PROBABLE CAUSE• Faulty battery• Faulty main and/or horn switch• Improperly adjusted horn• Faulty horn• Broken wireharness

9-8


FAULTY Y.P.V.S. PROBABLE CAUSE• Power valve • Seized or damaged power valve

• Carbon build-up

• Control cable • Improperly adjusted cable• Seized or discontinuous cable

• Electrical parts • Insufficient battery capacity(improperly charged battery)

• Faulty main switch• Faulty servomotor• Faulty CDI unit• Faulty Y.P.V.S. control unit• Broken or shorted wiring

OVERHEATING OR OVER-COOLINGOVERHEATING PROBABLE CAUSE

• Ignition system • Improper spark plug gap• Improper spark plug heat range• Faulty CDI unit

• Fuel system • Improper carburator main jet(improper setting)

• Improperly adjusted fuel heigh• Clogged air cleaner element• Lean mixture (Faulty Autolube pump

settings)

• Compression system • Heavy carbon build-up

• Transmission oil • Incorrect oil level• Improper oil viscosity• Inferior oil quality

• Brake • Dragging bike

• Cooling system • Faulty water temperature gauge• Faulty thermo-unit• Incorrect coolant level• Faulty thermostat valve• Clogged or damaged radiator• Faulty radiator cap• Seized impeller shaft

OVER-COOLING PROBABLE CAUSE• Cooling system • Faulty water temperature gauge

• Faulty thermo-unit• Faulty thermostat valve

9-9


DT125 WIRING DIAGRAM

COMPONENTS

1. CDI. Mag.2. Rect./Regu.3. Battery4. Fuse5. Starter Relay6. Starting Motor7. Main Sw.8. Handle Sw. R9. Starter Sw.10. E/G Stop Sw.11. Clutch Sw.12. Side Stand Sw.13. Thermo Sw.14. Side Stand Relay15. Neutral Sw.16. CDI. Unit17. Ign. Coil18. Servo. Motor19. Lightning Relay20. Horn Sw.21. Dimmer Sw.22. Flasher Sw.23. Hazard Sw.24. Handle Sw. L25. Horn26. Flasher Relay27. Fr. Stop Sw.28. Rr. Stop Sw.29. Head Light30. Fr. Lh Flasher31. Rr. Lh Flasher32. Fr. Rh Flasher33. Rr. Rh Flasher34. Tail/Stop Light35. Oil Level Gauge36. Meter37. Diode 138. License Light39. Position Lamp40. Anti Theft Unit

COLOR CODE

B ..........................BalckR ..........................RedL...........................BlueG..........................GreenOr.........................OrangeY ..........................YellowP ..........................PinkBr .........................BrownCh ........................ChocolateSb ........................Skip blueDg ........................Dark greenW .........................WhiteGy ........................GrayBG .......................Black-GreenBY........................Black-YellowBW.......................Black-WhiteGR .......................Green-RedGY........................Green-YellowBrW......................Brown-WhiteYR........................Yellow-RedLR ........................Blue-RedLY.........................Blue-YellowLG........................Blue-GreenRY ........................Red-YellowPW .......................Pink-WhiteWG.......................White-GreenWL .......................White-BlueWR.......................White-Red

Documents

Yamaha DT 125 X Re 2005 Manual de Reparatie Www.manualedereparatie.info