Yamaha SR125_Service Manual 3MW-AE1 1997 (English)

EB000000

SR125SERVICE MANUAL

1996 by Yamaha Motor Co., Ltd.1st Edition, September 1996

All rights reserved. Any reprinting orunauthorized use without the writtenpermission of Yamaha Motor Co., Ltd.

is expressly prohibited .

NOTE:

WARNING

CAUTION:

EB001000

NOTICEThis manual was produced by the Yamaha Motor Company primarily for use by Yamaha dealers andtheir qualified mechanics. It is not possible to include all the knowledge of a mechanic in one manual,so it is assumed that anyone who uses this book to perform maintenance and repairs on Yamaha mo-torcycle has a basic understanding of the mechanical ideas and the procedures of motorcycle repair.Repairs attempted by anyone without this knowledge are likely to render the motorcycle unsafe andunfit for use.

Yamaha Motor Company, Ltd., is continually striving to improve all its models. Modifications and signif-icant changes in specifications or procedures will be forwarded to all authorized Yamaha dealers andwill appear in future aditions of this manual where applicable.

Designs and specifications are subject to change without notice.

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

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

Failure to follow WARNING instructions could result in severe injury ordeath to the motorcycle operator, a bystander or a person inspecting orrepairing the motorcycle.

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

NOTE: A NOTE provides key information to make procedures easier or clearer.

12

6

7

6

4 3

8

YP002000

HOW TO USE THIS MANUAL

MANUAL ORGANIZATIONThis manual consists of chapters for the main categories of subjects. (See “Illustrated symbols”)

1st title 1 : This is the title of the chapter with its symbol on the upper right corner of each page.

2nd title 2 : This title indicates the section of the chapter and only appears on the first page of eachsection. It is located in the upper left corner of the page.

3rd title 3 : This title indicates a sub-section that is followed by step-by-step procedures accompa-nied by corresponding illustrations.

EXPLODED DIAGRAMSTo help identify parts and clarify procedure steps, there are exploded diagrams at start of each removaland disassembly section.1. An easy-to-see exploded diagram 4 is provided for disassembly and assembly jobs.2. Numbers 5 are given in the order of jobs in the exploded diagram. A number that is enclosed by a

circle indicates a disassembly step.3. An explanation of jobs and notes is presented in an easy-to-read way by the use of symbol marks

6 . The meanings of the symbol marks are given on the next page.4. A job instruction chart 7 accompanies the exploded diagram, providing the order of jobs, names of

parts, notes in jobs, etc.5. For jobs requiring more information, the step-by-step format supplements 8 are given in addition to

the exploded diagram and the job instruction chart.

21

1

3

5

7

9

2

4

8

6

23 24

2220

18 1917

15

1413

11 12

10

GENINFO SPEC

ENG

CARB

ELEC

CHAS

INSPADJ

TRBLSHTG

16

EB003000

ILLUSTRATED SYMBOLSIllustrated symbols 1 to 9 are designed asthumb tabs to indicate the chapter’s numberand content.

1 General information

2 Specifications

3 Periodic inspection and adjustment

4 Engine

5 Carburation

6 Chassis

7 Electrical

8 Troubleshooting

Illustrated symbols 9 to 16 are used to identifythe specifications appearing in the text.

9 Possible to maintain with engine mounted

10 Filling fluid

11 Lubricant

12 Special tool

13 Tightening

14 Wear limit, clearance

15 Engine speed

16 Ω , V, A

Illustrated symbols 17 to 22 in the exploded dia-grams indicate the types of lubricants and lu-brication points.17 Apply engine oil

18 Apply gear oil

19 Apply molybodenum disulfide oil

20 Apply wheel bearing grease

21 Apply lightweight lithium-soap baes grease

22 Apply molybdenum disulfide grease

Illustrated symbols 23 to 24 in the exploded dia-grams indicate the where to apply locking agent23 and when to install new parts 24 .

23 Apply locking agent (LOCTITE )

24 Use new one

GENERAL INFORMATION

SPECIFICATIONS

PERIODIC INSPECTION ANDADJUSTMENT

ENGINE OVERHAUL

CARBURATION

CHASSIS

ELECTRICAL

TROUBLESHOOTING

GENINFO 1SPEC 2

3ENG 4

CARB 5CHAS 6ELEC 7TRBLSHTG 8

INSPADJ

INDEX

CHAPTER 1.GENERAL INFORMATION

MOTORCYCLE IDENTIFICATION 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FRAME SERIAL NUMBER 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ENGINE SERIAL NUMBER 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MODEL LABEL 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

IMPORTANT INFORMATION 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PREPARATION FOR REMOVAL PROCEDURES 1-2. . . . . . . . . . . . . . . REPLACEMENT PARTS 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GASKETS, OIL SEALS AND O-RINGS 1-2. . . . . . . . . . . . . . . . . . . . . . . . LOCK WASHERS/PLATES AND COTTER PINS 1-3. . . . . . . . . . . . . . . . BEARINGS AND OIL SEALS 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CIRCLIPS 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CHECKING OF CONNECTIONS 1-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

HOW TO USE THE CONVERSION TABLE 1-5. . . . . . . . . . . . . . . . . . . . . . . .

SPECIAL TOOLS 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-1

MOTORCYCLE IDENTIFICATIONGENINFO

NOTE:

YP100000

GENERAL INFORMATIONMOTORCYCLE IDENTIFICATIONSR100020

FRAME SERIAL NUMBERThe frame serial number 1 is stamped into theright side of the frame.

EB100030

ENGINE SERIAL NUMBERThe engine serial number 1 is stamped into thecrankcase.

Designs and specifications are subject tochange without notice.

MODEL LABELThe model label 1 is affixed under the seat.This information will be needed to order spareparts.

1-2

IMPORTANT INFORMATIONGENINFO

EB101000

IMPORTANT INFORMATIONPREPARATION FOR REMOVAL PROCE-DURES1. Remove all dirt, mud, dust and foreign mate-

rial before removal and disassembly.2. Use proper tools and cleaning equipment.3. Refer to the “SPECIAL TOOLS” section.4. When disassembling the machine, always

keep mated parts together. This includesgears, cylinders, pistons and other parts thathave been “mated” through normal wear.Mated parts must always be reused or re-placed as an assembly.

5. During machine disassembly, clean all partsand place them in trays in the order of disas-sembly. This will speed up assembly and al-low for the correct installation of all parts.

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

NB101010

REPLACEMENT PARTS1. Use only genuine Yamaha parts for all re-

placements. Use oil and grease recom-mended by Yamaha for all lubrication jobs.Other brands may be similar in function andappearance, but inferior in quality.

EB101020

GASKETS, OIL SEALS AND O-RINGS1. Replace all gaskets, seals and O-rings when

overhauling the engine. All gasket surfaces,oil seal lips and O-rings must be cleaned.

2. Properly oil all mating parts and bearingsduring reassembly. Apply grease to the oilseal lips.

1-3

OR

IMPORTANT INFORMATIONGENINFO

CAUTION:

EB101030

LOCK WASHERS/PLATES AND COTTERPINS1. Replace all lock washers/plates and cotter

pins after removal. Bend lock tabs along thebolt or nut flats after the bolt or nut has beentightened to specification.

EB101040

BEARINGS AND OIL SEALSInstall bearings and oil seals so that themanufacturer’s marks or numbers are visible.When installing oil seals, apply a light coating oflightweight lithium base grease to the seal lips.Oil bearings liberally when installing, if ap-propriate.

1 Oil seal

Do not use compressed air to spin the bear-ings dry. This will damage the bearing sur-faces.

1 Bearing

EB101050

CIRCLIPS1. Check all circlips carefully before reassemb-

ly. Always replace piston pin clips after oneuse. Replace distorted circlips. When instal-ling a circlp 1 , make sure that the sharp-edged corner 2 is positioned opposite thethrust 3 it receives. See sectional view.

4 Shaft

1-4

CHECKING OF CONNECTIONSGENINFO

NOTE:

NOTE:

EB801000

CHECKING OF CONNECTIONSDealing with stains, rust, moisture, etc. on theconnector.1. Disconnect:Connector

2. Dry each terminal with an air blower.

3. Connect and disconnect the connector twoor three.

4. Pull the lead to check that it will not come off.5. If the terminal comes off, bend up the pin 1

and reinsert the terminal into the connector.

6. Connect:Connector

The two connectors “click” together.

7. Check for continuity with a tester.

If there is no continuity, clean the terminals.Be sure to perform the steps 1 to 7 listed abovewhen checking the wireharness.

For a field remedy, use a contact revitalizeravailable on the market.

Use the tester on the connector as shown.

1-5

HOW TO USE THE CONVERSION TABLEGENINFO

EB201000

HOW TO USE THE CONVERSION TABLEAll specification data in this manual are listed in Sl and METRIC UNITS.Use this table to convert METRIC unit data to IMPERIAL unit data.Ex.METRIC MULTIPLIER IMP

** mm 0.03937 = ** in 2 mm 0.03937 = 0.08 in

CONVERSION TABLE

METRIC TO IMP

Known Multiplier Result

Torque

mkgmkgcmkgcmkg

7.23386.7940.07230.8679

ftlbinlbftlbinlb

Weight kgg

2.2050.03527

lboz

Distance

km/hrkmmmcmmm

0.62140.62143.2811.0940.39370.03937

mphmiftydinin

Volume/Capacity

cc (cm3)cc (cm3)lit (liter)lit (liter)

0.035270.061020.87990.2199

oz (IMP liq.)cuinqt (IMP liq.)gal (IMP liq.)

Miscellaneouskg/mmkg/cm2

Centigrade

55.99714.22349/5 (C) + 32

lb/ inpsi (lb/ in2)Fahrenheit (F)

1-6

SPECIAL TOOLSGENINFO

EB102000

SPECIAL TOOLSThe following special tools are necessary for complete and accurate tune-up and assembly. Use onlythe appropriate special tools; this will help prevent damage caused by the use of inappropriate tools orimprovised techniques.When placing an order, refer to the list provided below to avoid any mistakes.

Tool No. Tool name/Usage Illustration

90890-0108090890-04052

Rotor pullerAttachment

This tool is used when removing or installingthe meter gear bush.

90890-0108390890-01084

Rocker arm shaft puller boltWeight

These tools are used when removing orinstalling the rocker arm shafts.

90890-01268 Ringnut wrench

This tool is used to loosen and tighten theexhaust and steering ringnut.

90890-01311 Valve adjusting tool

This tool is necessary for adjusting valveclearance.

90890-01312 Fuel level gauge

This gauge is used to measure the fuel levelin the float chamber.

90890-0136790890-01400

Fork seal driver weightFork seal driver attachment (ø30 mm)

This tool is used when installing the fork seal.

90890-01403 Ring nut wrench

This tool is used to loosen and tighten thesteering ring nut.

90890-01701 Sheave holder

This tool is used for holding the secondarysheave.

90890-01996 Cylinder cup installer set

This tool is used for installing the cylindercup to the master cylinder piston.

1-7



90890-03079 Thickness gauge

This tool is used to measure the valveclearance.

90890-0308190890-04082

Compression gaugeAdaptor

These tools are used to measure the enginecompression.

90890-03112 Pocket tester

These instruments are invaluable forchecking the electrical system.

90890-03113 Engine tachometer

This tool is needed for detecting engine rpm.

90890-03141 Timing light

This tool is necessary for checking ignitiontiming.

90890-0401990890-04108

Valve spring compressorAttachment

These tools are used when removing orinstalling the valve and the valve spring.

90890-04064 Valve guide remover 6 mm

This tool is used to remove the valve guide.

90890-04065 Valve guide reamer 6 mm

This tool is used to rebore the valve guide.

90890-04066 Valve guide installer 6 mm

This tool is needed to install the valve guidesproperly.

90890-04086 Clutch holding tool

This tool is used for holding the Clutch Boss.

1-8



90890-04101 Valve lapper

This tool is used for removing and installingthe lifter and for lapping the valve.

90890-06754 Ignition checker

This instrument is necessary for checking theignition system components.

90890-85505 Yamaha bond No.1215

This sealant (bond) is used for crankcasemating surface, etc.

CHAPTER 2.SPECIFICATIONS

GENERAL SPECIFICATIONS 2-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

MAINTENANCE SPECIFICATIONS 2-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ENGINE 2-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CHASSIS 2-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ELECTRICAL 2-13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

GENERAL TORQUE SPECIFICATIONS 2-15. . . . . . . . . . . . . . . . . . . . . . . . . .

LUBRICATION POINT AND GRADE OF LUBRICANT 2-16. . . . . . . . . . . . . ENGINE 2-16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CHASSIS 2-17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

LUBRICATION DIAGRAM 2-18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CABLE ROUTING 2-20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2-1

GENERAL SPECIFICATIONS SPEC

SPECIFICATIONS

GENERAL SPECIFICATIONS

Model SR125

Model code: 3MW6

Dimensions:Overall lengthOverall widthOverall heightSeat heightWheelbaseMinimum ground clearanceMinimum turning radius

1,915 mm775 mm1,080 mm745 mm1,280 mm155 mm2,100 mm

Basic weight:With oil and full fuel tank 113 kg

Engine:Engine typeCylinder arrangementDisplacementBore strokeCompression ratioCompression pressure (STD)Starting systemLubrication system:

Air-cooled 4-stroke, SOHCForward-inclined single cylinder0.124 L (124 cm3)57.0 48.8 mm10.0 : 11,200 kPa (12.0 kg/cm2, 12.0 bar) at 1,000 r/minElectric starterWet sump

Oil type or grade:Engine oil API “SE” or higher grade

Periodic oil changeWith oil filter replacementTotal amount

1.0 L1.1 L1.3 L

Air filter: Wet type element

Fuel:TypeFuel tank capacityFuel reserve capacity

Regular unleaded gasoline10.0 L1.6 L

2-2


Model SR125

Carburetor:Type/quantityManufacturer

Y24P/1TEIKEI

Spark plug:TypeManufacturerSpark plug gap

DR8EANGK0.6 0.7 mm

Clutch type: Wet, multiple-disc

Transmission:Primary reduction systemPrimary reduction ratioSecondary reduction systemSecondary reduction ratioTransmission typeOperationGear ratio 1st

2nd3rd4th5th

Spur gear73/22 (3.318)Chain drive49/14 (3.500)Constant mesh 5 speedLeft foot operation36/16 (2.250)31/21 (1.476)27/24 (1.125)25/27 (0.926)23/29 (0.793)

Chassis:Frame typeCaster angleTrail

Diamond26.7590 mm

Tire:TypeSize front

rearManufacture front

rearType front

rear

Tube type3.00-17 45P3.50-16 52PINOUEINOUE8F8RA

Tire pressure (cold tire):Maximum load-except motorcycleLoading condition A *

frontrear

Loading condition B *frontrear

164 kg0 90 kg175 kPa (1.75 kg/cm2, 1.75 bar)200 kPa (2.0 kg/cm2, 2.0 bar)90 205 kg175 kPa (1.75 kg/cm2, 1.75 bar)225 kPa (2.25 kg/cm2, 2.25 bar)

*Load is the total weight of cargo, rider, passenger, and accessories.

2-3


Model SR125

Brake:Front brake type

operationRear brake type

operation

Single disc brakeRight hand operationDrum brakeRight foot operation

Suspension:Front suspensionRear suspension

Telescopic forkSwingarm

Shock absorber:Front shock absorberRear shock absorber

Coil spring/Oil damperCoil spring/Oil damper

Wheel travel:Front wheel travelRear wheel travel

120 mm78 mm

Electrical:Ignition systemGenerator systemBattery typeBattery capacity

C.D.I.C.D.I. magneto12N 7-3B12 V 7 AH

Headlight type: Bulb type

Bulb wattage quantity:HeadlightAuxiliary lightTail /brake lightFlasher lightMeter lightHigh beam indicatorNeutral indicatorTURN indicator

12 V 36 W/36 W 112 V 4 W 112 V 5 W/21 W 112 V 21 W 412 V 3.4 W 112 V 3.4 W 112 V 3.4 W 112 V 3.4 W 2

2-4

MAINTENANCE SPECIFICATIONS SPEC

Head Dia. Face Width Seat Width Margin Thickness

MAINTENANCE SPECIFICATIONSENGINE

Item Standard Limit

Cylinder head:Warp limit 0.03 mm

Cylinder:Bore sizeTaper limitOut of round limit

57.00 57.02 mm

57.1 mm0.05 mm0.01 mm

Camshaft:Cam dimensionsIntake “A”

“B”“C”

Exhaust “A”“B”“C”

Camshaft runout limit

36.537 36.637 mm30.131 30.231 mm6.59 mm36.577 36.677 mm30.214 30.314 mm6.63 mm

36.45 mm30.05 mm

36.49 mm30.13 mm

0.03 mm

Cam chain:Cam chain type/No. of linksCam chain adjustment

DID 25SH/104 ENDLESSManual

Rocker arm/rocker armshaft:Rocker arm inside diameterRocker shaft outside diameterRocker arm-to-rocker armshaftclearance

12.000 12.018 mm11.985 11.991 mm

0.009 0.033 mm

12.036 mm11.950 mm

Valve, valve seat, valve guide:Valve clearance (cold) IN

EX0.05 0.09 mm0.11 0.15 mm

Valve dimensions

“A” head diameter INEX

“B” face width INEX

“C” seat width INEX

“D” margin thickness INEX

Stem outside diameter INEX

28.9 29.1 mm23.9 24.1 mm2.4 2.8 mm2.4 2.8 mm0.9 1.1 mm0.9 1.1 mm0.8 1.2 mm0.8 1.2 mm5.975 5.990 mm5.960 5.975 mm

5.955 mm5.940 mm

2-5


Item Standard Limit

Guide inside diameter INEX

Stem-to-guide clearance INEX

Stem runout limitValve seat width IN

EX

6.000 6.012 mm6.000 6.012 mm0.010 0.037 mm0.025 0.052 mm

0.9 1.1 mm0.9 1.1 mm

6.042 mm6.042 mm0.08 mm0.10 mm0.03 mm1.6 mm1.6 mm

Valve spring:Free length (inner) IN/EX

(outer) IN/EXSet length (valve closed)

(inner) IN/EX(outer) IN/EX

Compressed pressure(inner) IN/EX(outer) IN/EX

Tilt limit (inner) IN/EXTilt limit (outer) IN/EXDirection of winding (inner) IN/EXDirection of winding (outer) IN/EX

35.5 mm37.2 mm

22.5 mm24.0 mm

26.7 30.7 kg52.4 40.2 kg

ClockwiseCounterclockwise

33.5 mm35.2 mm

2.5/1.5 mm2.5/1.5 mm

Piston:Piston to cylinderclearancePiston size “D”Piston over size (1st)Piston over size (2nd)Measuring point “H”Piston off-setPiston off-set directionPiston pin boreinside diameterPiston pin outside diameter

0.025 0.045 mm

56.960 56.975 mm57.25 mm57.50 mm7.0 mm0.5 mmIN side15.002 15.013 mm

14.978 14.992 mm

15.045 mm

14.975 mm

Piston rings:Top ring:TypeDimensions (B T)End gap (installed)Side clearance (installed)

2nd ring:TypeDimensions (B T)End gap (installed)Side clearance

Oil ring:Dimensions (B T)End gap (installed)

Plane2.3 2.5 mm0.15 0.35 mm0.03 0.07 mm

Plane2.3 2.5 mm0.15 0.35 mm0.02 0.06 mm

2.5 2.8 mm0.3 0.9 mm

0.60 mm0.15 mm

0.60 mm0.15 mm

2-6


Item Standard Limit

Crankshaft:

Crank width “A”Runout limit “C”Big end side clearance “D”Big end radial clearanceSmall end free play “F”

55.95 56.00 mm

0.35 0.65 mm0.010 0.025 mm0.8 1.0 mm

0.03 mm1.0 mm

Clutch:Friction plate thicknessQuantity

Clutch plate thicknessQuantity

Clutch spring free lengthQuantity

Push rod bending limit

2.9 3.1 mm4 pcs.1.6 mm3 pcs.34.9 mm4 pcs.

2.7 mm

0.05 mm

32.9 mm

0.2 mm

Transmission:Main axle runout limitDrive axle runout limit

0.08 mm0.08 mm

Carburetor:TypeI.D. markMain jet (M.J)Main air jet (M.A.J)Jet needle (J.N)Needle jet (N.J)Cut away (C.A)Pilot outlet (P.O)Pilot jet (P.J)Bypass 1 (B.P.1)Pilot screw (P.S)Valve seat size (V.S)Starter jet 1 (G.S.1)Starter jet 2 (G.S.2)Float height (F.H)Engine idle speedIntake vacuumCOOil temperature

Y24P4WP-10#102ø1.34C9A-3/52.6002.250.8#381.02ø2.0#60#6428.5 mm1,250 1,350 r/min180 200 mmHg4.5 5.5%60 70C

Oil pump;TypeTip clearanceSide clearanceBypass valve setting pressure

Trochoid type0.03 0.09 mm0.10 0.15 mm80 120 kPa(0.8 1.2 kg/cm2, 0.8 1.2 bar)

0.14 mm0.35 mm

2-7


TIGHTENING TORQUESENGINE

Th dTightening

Part to be tightened Part name Threadsize

Q’tyg gtorque Remarksg

sizey

Nm mkg

Cylinder head blind plugCylinder head and cylinderCylinder head(Timing chain side)Cam sprocket coverValve coverPlateSpark plugCylinderBuffer bossC.D.I. magnetoValve adjuster locknutCam sprocketTiming chain tensioner(Body)(Cap)Timing chain guide (intake)Oil pumpOil pump and crankcaseDrain plugOil filter coverDrain bolt (oil filter)Carburetor joint and carburetorCarburetor joint and cylinderCarburetor joint and air filterAir filter caseAir filter case and frameMuffler and frameExhaust pipe and cylinderCrankcase (left and right)Crankcase cover (left)Crankcase cover (left)Crankcase cover (right)Drive sprocket coverStarter clutchKick crankPrimary drive gearClutch springClutch bossPush lever axlePush lever adjuster

ScrewBoltBolt

ScrewBoltBolt—

BoltNutBoltNutBolt

NutNutBolt

ScrewScrewBolt

ScrewBolt

ScrewScrewScrewScrewScrew

BoltBolt

ScrewScrewScrewScrewScrewBoltBoltNut

ScrewNut

ScrewNut

M6M8M8

M6M6M6

M12M6

M14M10M6

M10

M14M14M6M6M6

M35M6M6M6M5M5M5M6M8M6M6M6M4M6M6M8

M32M14M5

M14M8M6

242

252121121

1121312121122221391923114111

72220

7108

181050501460

305877

437

10122447201277277

30

506

70128

0.72.22.0

0.71.00.81.81.05.05.01.46.0

3.00.50.80.70.74.30.71.01.20.20.40.40.72.01.20.70.70.20.70.73.0

5.00.67.01.20.8

Stake

2-8


Part to be tightened Part nameThread

size Q’tyTightening

torque Remarksg size yNm mkg

Drive sprocketShift cam (Segment)Shift pedalPick up coilNeutral switchStator coilStarter motor

BoltScrewBolt

ScrewScrewScrewScrew

M6M6M6M6

M10M4M6

2114161

101287

2037

1.01.20.80.72.00.30.7

2-9


Tightening sequenceCylinder head

Crankcase

Item Standard Limit

2-10


CHASSIS

Item Standard Limit

Steering system:Steering bearing typeNo./size of steel balls (upper)

(lower)

Ball bearing22 pcs. 0.1875 in19 pcs. 0.251 in

Front suspension:Front fork travelFork spring free lengthFitting lengthSpring rate (K1)

(K2)Stroke (K1)

(K2) Oil capacity Oil level Oil grade Inner tube vend limit

120 mm326.1 mm311.1 mm3.6 N /mm (0.36 kg/mm)5.1 N/mm (0.51 kg/mm)0 85 mm85 120 mm0.177 L (177 cm3)135 mmFork oil 15 WT or equivalent

321 mm

0.2 mm

Rear suspension:Shock absorber strokeSpring free lengthFitting lengthSpring rate (K1)

(K2)Stroke (K1)

(K2)

65 mm178.5 mm198 mm18.3 N/mm (1.83 kg/mm)21.6 N/mm (2.16 kg/mm)0 30 mm30 65 mm

173 mm

Front wheel:TypeRim sizeRim materialRim runout limit radial

lateral

Spoke wheel17 1.60Steel

2 mm2 mm

Rear wheel:TypeRim sizeRim materialRim runout limit radial

lateral

Spoke wheel16 1.85Steel

2 mm2 mm

Drive chain:Type/manufacturerNo. of linksChain free play

428HG/DAIDO12025 35 mm

2-11


Item Standard Limit

Front brake:TypeDisc outside diameterDisc thicknessPad thickness (inner)

(outer)Master cylinder inside diameterCaliper cylinder 1 inside diameterCaliper cylinder 2 inside diameterBrake fluid type

Single disc267 mm4 mm6.2 mm6.2 mm12.7 mm30.16 mm25.4 mmDOT#4 or DOT#3

3.5 mm0.8 mm0.8 mm

Rear brake:TypeDrum inside diameterShoe thicknessShoe spring free length

Leading, trailing110 mm4 mm50.5 mm

111 mm2 mm

Brake lever:Brake lever free play (at lever end) 2 5 mm

Brake pedal:Brake pedal free playBrake pedal position

20 30 mm0 mm

Clutch lever:Clutch lever free play (at lever end) 10 15 mm

Throttle cable free play 3 5 mm

2-12


NOTE:

TIGHTENING TORQUESCHASSIS

Part to be tightened Thread sizeTightening

torque RemarksgNm mkg

Handle crown and front forkHandle crown and steering shaftHandlebar holder (under and upper)Steering ring nutMaster cylinder and cap (front brake)Handlebar under holder and nutMaster cylinder (front brake)Brake hose union bolt (front brake)Front flasher and staySteering shaft and front forkEngine and front engine stayFront engine stay and frameEngine and top engine stayTop engine stay and frameEngine and engine bracket (frame)Swingarm pivot shaftRear shock absorber and frameRear shock absorber and swingarmSwingarm and tension barTension bar and rear brake shoe plateGrab bar and frameFuel tank an fuel cockRear flasher and staySidestand (bolt)Sidestand (nut)Rear footrest (left)Front wheel axleRear wheel axle and nutBrake caliper and front forkBrake disc and front wheelDriven sprocket and clutch hubBrake caliper bleed screwMeter gear and meter cableBrake cam leverFront wheel axle pinch bolt

M10M10M8

M25M4

M10M6

M10M12M10M8M8M8M8M8

M12M10M10M8M8M8M6

M12M8M8

M10M14M14M10M8

M10M7

M12M6M8

45402072

409

304

30333333333345403020201674

1916455965402340639

20

4.54.02.00.70.24.00.93.00.43.03.33.33.33.33.34.54.03.02.02.01.60.70.41.91.61.55.96.54.02.34.00.60.30.92.0

Refer to NOTE

1. When tighten the ring nut, should be steady the ball bearings and the steering shaft moving smooth-ly.

2. First, tighten the ring nut approximately 38 Nm (3.8 mkg) by using the torque wrench, then loosenthe ring nut one turn and retighten the ring nut to specification.

2-13


ELECTRICAL

Item Standard Limit

Ignition timing:Ignition timing (B.T.D.C.)Advanced timingAdvanced type

9 at 1,300 r/min29 at 5,500 r/minElectrical type

C.D.I.:Pickup coil resistance/color

Source coil resistance/color

C.D.I. unit model/manufacturer

656 984 Ω at 20C/Red – White624 936 Ω at 20C/Brown – Green4WP/YAMAHA

Ignition coil:Model/ manufacturerMinimum spark gapPrimary winding resistanceSecondary winding resistance

2JN/YAMAHA6 mm0.32 0.48 Ω at 20C5.68 8.52 kΩ at 20C

Spark plug cap:TypeResistance

Resin type10 kΩ

Charging system:TypeModel/manufacturerStandard outputStator coil resistance/color

C.D.I. magneto4WP/YAMAHA14 V 9 A/5,000 r/min0.48 0.72 Ω at 20C/White – White

Rectifier/regulator:Model/manufacturerType (regulator)No load regulated voltageCapacity (rectifier)Withstand voltage

SH553D/SHINDENGENSemi conductor-short circuit type14.5 V25 A200 V

Battery:Specific gravity 1.280

Electric starter system:TypeStarter motor:Model/ manufacturerOutputArmature coil resistanceBrush overall lengthBrash spring pressureCommutator diameterMica undercut (depth)

Constant mesh type

SM-14/MITUBA0.6 kW0.0207 0.0253 Ω at 20C10 mm5.30 6.47 N28 mm0.7 mm

3.5 mm

27 mm

2-14


Item Standard Limit

Starter relay:Model/manufacturerAmperage ratingCoil winding resistance

MS5D-191/JIDECO100 A3.9 4.7 Ω at 20C

Horn:Model/manufacturerMaximum amperage

YF-12/NIKKO2.5 A

Flasher relay:TypeModel/manufacturerFlasher frequency

Condenser typeFR2204/MITUBA85 cycle/min

Circuit breaker:TypeMainReserve

Fuse20 A 1 pcs.20 A 1 pcs.

2-15

GENERAL TORQUE SPECIFICATIONS SPEC

GENERAL TORQUE SPECIFICATIONSThis chart specifies torque for standard fasten-ers with standard I.S.O. pitch threads. Torquespecifications for special components or as-semblies are included in the applicable sectionsof this book. To avoid warpage, tighten multi-fastener assemblies in a crisscross fashion, inprogressive stages, until full torque is reached.Unless otherwise specified, torque specifica-tions call for clean, dry threads. Componentsshould be at room temperature.

A: Distance across flats

B: Outside thread diameter

A(Nut)

B(Bolt)

General torquespecifications

(Nut) (Bolt)Nm mkg

10 mm 6 mm 6 0.6

12 mm 8 mm 15 1.5

14 mm 10 mm 30 3.0

17 mm 12 mm 55 5.5

19 mm 14 mm 85 8.5

22 mm 16 mm 130 13.0

2-16

LUBRICATION POINT AND GRADE OF LUBRICANT SPEC

LUBRICATION POINT AND GRADE OF LUBRICANTENGINE

Lubrication Point Symbol

Oil seal lips (all)

Bearing retainer (all)

Bolt (cylinder head)

Crank pin

Connecting rod (big end)

Piston pin

Piston/piston ring

Buffer boss

Valve stem/valve guide (IN, EX)

Valve stem end (IN, EX)

Rocker arm shaft

Cam and bearing (camshaft)

Rocker arm inner surface

Crankcase mating surfaces Yamaha bond No.1215

O-ring (all)

Starter idle gear thrust surfaces

Starter clutch (outer/roller)

Starter wheel gear inner surface

Push rod

Primary driven gear inner surface

Push lever axle

Transmission gear inner surface

Shift fork/guide bar

2-17

LUBRICATION POINT AND GRADE OF LUBRICANT SPEC

CHASSIS

Lubrication Point Symbol

Steering head pipe bearing (upper/ lower)

Front wheel oil seal lips (left /right)

Rear wheel oil seal lips (left /right)

Rear wheel hub

Rear brake shoe plate, camshaft and pivoting pin

Pivoting points (brake pedal shaft and frame)

Sidestand sliding surface/mounting bolt

Pivoting point (centerstand)

Tube guide (throttle grip) inner surface

Brake lever bolt /master cylinder sliding surface

Clutch lever bolt /cable sliding surface

Steering lock sliding surface

Gear unit (speedometer)

Chain guard inner surface/swigarm insert surface

2-18

1 Rocker arm (IN)2 Rocker shaft3 Rocker arm (EX)4 Camshaft5 Oil pump6 Push lever

LUBRICATION DIAGRAM SPEC

LUBRICATION DIAGRAM

2-19

1 Oil pump2 Oil filter3 Crankshaft4 Main axle5 Drive axle6 Oil strainer

LUBRICATION DIAGRAM SPEC

2-20

A Clamp the handlebar switchlead, (left and right), front brakeswitch lead, clutch switch lead tothe handlebar.

B Do not contact the horn and wire-harness.

12 Clutch switch coupler13 Handlebar switch lead (left)14 Front flasher lead (left)15 Horn lead16 Flasher relay17 Handlebar switch lead (right)18 Front brake switch lead19 Front flasher (right)20 Meter lead21 Front flasher lead (right)22 Wireharness

1 Front brake switch lead2 Brake hose3 Handlebar switch lead (right)4 Throttle cable5 Clutch cable6 Clutch switch lead7 Handlebar switch lead (left)8 Speedometer cable9 Clamp10 Main switch coupler11 Front flasher (left)

CABLE ROUTING SPEC

CABLE ROUTING

2-21

A Align the clamp to the white tapeon the wireharness

B Pass the clutch cable throughthe outside of the throttle cable.

C Pass the brake hose and throttlecable through the slit of theheadlight body. And pass themthe right inside of the front fork.

D Pass the brake hose to the holder.E Clamp the clutch cable to the

down tube of the frame.

CABLE ROUTING SPEC

1 Clamp2 Wireharness3 High tension cord4 Collar5 Ignition coil6 Ground lead7 Ignition coil lead8 Brake hose9 Clutch cable10 Rear brake switch11 Starting circuit cut-off relay12 Battery breather hose

2-22

A Clamp the speedometer cable tothe steering bracket and passthe cable to the cable holder.

B Pass the brake hose through thebrake hose holder.

14 Rectifier /Regulator15 Thermostatic switch16 Throttle cable17 Clutch cable18 Wireharness19 Speedometer cable20 Cable holder21 Brake hose holder22 Cable holder23 Brake hose24 Starter motor lead25 Sidestand switch26 Rectifier /Regulator lead

CABLE ROUTING SPEC

1 Neutral switch lead2 Pickup coil lead3 C.D.I. unit4 Rear flasher lead (right)5 Rear flasher lead (left)6 Tail /Brake light lead7 C.D.I. magneto lead8 Thermostatic switch lead9 Clamp10 Sidestand switch lead11 Starter relay lead12 Fuse13 Starter relay

2-23

CABLE ROUTING SPEC

1 Air filter case2 Battery3 Swingarm4 Battery breather pipe5 Lid6 Air filter case drain pipeA Pass the air filter case drain pipe

inside the swingarm.

SPEC

CHAPTER 3.PERIODIC INSPECTIONS

AND ADJUSTMENTS

INTRODUCTION 3-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

PERIODIC MAINTENANCE/LUBRICATION INTERVALS 3-1. . . . . . . . . . .

SIDE COVER, SEAT AND FUEL TANK 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . .

ENGINE 3-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VALVE CLEARANCE ADJUSTMENT 3-4. . . . . . . . . . . . . . . . . . . . . . . . . . IDLING SPEED ADJUSTMENT 3-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . THROTTLE CABLE ADJUSTMENT 3-6. . . . . . . . . . . . . . . . . . . . . . . . . . . SPARK PLUG INSPECTION 3-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . IGNITION TIMING CHECK 3-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . COMPRESSION PRESSURE MEASUREMENT 3-9. . . . . . . . . . . . . . . . ENGINE OIL LEVEL INSPECTION 3-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . ENGINE OIL REPLACEMENT 3-11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TIMING CHINE TENSIONER ADJUSTMENT 3-13. . . . . . . . . . . . . . . . . . . CLUTCH ADJUSTMENT 3-13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AIR FILTER CLEANING 3-14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . EXHAUST SYSTEM INSPECTION 3-15. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CHASSIS 3-17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FRONT BRAKE ADJUSTMENT 3-17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . REAR BRAKE ADJUSTMENT 3-17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BRAKE FLUID LEVEL INSPECTION 3-19. . . . . . . . . . . . . . . . . . . . . . . . . . BRAKE PAD INSPECTION 3-20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BRAKE SHOE INSPECTION 3-20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BRAKE LIGHT SWITCH ADJUSTMENT 3-20. . . . . . . . . . . . . . . . . . . . . . . AIR BLEEDING 3-21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DRIVE CHAIN SLACK ADJUSTMENT 3-22. . . . . . . . . . . . . . . . . . . . . . . . . STEERING HEAD INSPECTION 3-24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FRONT FORK INSPECTION 3-25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . REAR SHOCK ABSORBER ADJUSTMENT 3-25. . . . . . . . . . . . . . . . . . . . TIRE INSPECTION 3-26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SPOKE INSPECTION AND TIGHTENING 3-28. . . . . . . . . . . . . . . . . . . . . WHEEL INSPECTION 3-28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ELECTRICAL 3-29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BATTERY INSPECTION 3-29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FUSE INSPECTION 3-31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HEADLIGHT BEAM ADJUSTMENT 3-32. . . . . . . . . . . . . . . . . . . . . . . . . . .

3-1

INTRODUCTION/PERIODIC MAINTENANCE/LUBRICATION INTERVALS

INSPADJ

10

11

12

13

14

15

16

17

EB300000

PERIODIC INSPECTIONS AND ADJUSTMENTS

INTRODUCTIONThis chapter includes all information necessary to perform recommended inspections and adjust-ments. These preventive maintenance procedures, if followed, will ensure more reliable vehicle opera-tion and a longer service life. The need for costly overhaul work will be greatly reduced. This informa-tion applies to vehicles already in service as well as to new vehicles that are being prepared for sale. Allservice technicians should be familiar with this entire chapter.YP301000

PERIODIC MAINTENANCE/LUBRICATION INTERVALSEVERY

NO. ITEM ROUTINEBRAKE-IN1,000 KM

6,000 kmor

6 months

12,000 kmor

12 months

1 * Valve(s) Check valve clearance. Adjust if necessary.

2 * Cam chain Check chain tension. Adjust if necessary.

3 Spark plugCheck condition.Clean or replace if necessary.

4 Air filter Clean. Replace if necessary.

5 * CarburetorCheck idle speed/starter operation.Adjust if necessary.

6 * Fuel lineCheck fuel hose for cracks or damage.Replace if necessary.

7 Engine oil Replace (Warm engine before draining.)

8 * Engine oil filter Replace

9 * Front brakeCheck operation/ fluid leakage. /see NOTE.Correct if necessary.

Rear brake Check operation. Adjust if necessary.

Clutch Check operation. Adjust if necessary.

* Rear arm pivotCheck rear arm assembly for looseness.Correct if necessary. Moderately repackevery 24,000 km or 24 months.***

* WheelsCheck balance/damage/runout /spoke tightness.Replace if necessary.

* Wheel bearingsCheck bearing assembly for looseness/damage.Replace if damaged.

*Steeringbearing

Check bearing assembly for looseness.Correct if necessary.Moderately repack every 24,000 km or24 months.**

* Front forksCheck operation/oil leakage.Repair if necessary.

*Rear shockabsorber

Check operation/oil leakage.Repair if necessary.

*: It is recommended that these items be serviced by a Yamaha dealer.**: Medium weight wheel bearing grease. (bearing type)***: Lithium soap base grease. (bush type)

3-2

PERIODIC MAINTENANCE/LUBRICATION INTERVALSINSPADJ

18

19

20

21

NOTE:

EVERY

NO. ITEM ROUTINEBRAKE-IN1,000 KM

6,000 kmor

6 months

12,000 kmor

12 months

Drive chainCheck chain slack/alignment. Adjust if necessary.Clean and lube.

EVERY 500 km

* Chassis fastenersCheck all chassis fittings and fasteners.Correct if necessary.

* SidestandCheck operation.Repair if necessary.

* BatteryCheck specific gravity.Check breather pipe for proper operation.Correct if necessary.

*: It is recommended that these items be serviced by a Yamaha dealer.**: Medium weight wheel bearing grease. (bearing type)***: Lithium soap base grease. (bush type)

Brake fluid replacement:1. When disassembling the master cylinder or caliper cylinder, replace the brake fluid.

Normally check the brake fluid level and fill the fluid as required.2. On the inner parts of the master cylinder and caliper cylinder, replace the oil seals every two years.3. Replace the brake hoses every four years, or if cracked or damaged.

3-3

Order Job name/Part name Q’ty Remarks

1234

5

Side cover, seat and fuel tankremovalSide cover (left)Side cover (right)SeatFuel pipe

Fuel tank

1111

1

Remove the parts in order.

Reverse the removal procedure for instal-lation.

Disconnect the fuel pipe, set the fuel cocklever “OFF” position.

NOTE:

SIDE COVER, SEAT AND FUEL TANKINSPADJ

SIDE COVER, SEAT AND FUEL TANK

3-4

VALVE CLEARANCE ADJUSTMENTINSPADJ

NOTE:

***************************************

***************************************

SR03004

ENGINEVALVE CLEARANCE ADJUSTMENT

Valve clearance adjustment should be madewith the engine cool, at room temperature.When the valve clearance is to be measured oradjusted, the piston must be at Top Dead Cen-ter (T.D.C.) on the compression stroke.

1. Remove:SeatSide cover (left and right)Fuel tankRefer to “SIDE COVER, SEAT AND FUELTANK” section.

2. Remove:Spark plug cap 1Spark plugValve cover (intake side) 2Valve cover (exhaust side) 3

3. Remove:Timing check plug (with O-ring) 1Center plug (with O-ring) 2

4. Measure:Valve clearanceOut of specification Adjust.

Valve clearance (cold):Intake valve 0.05 0.09 mmExhaust valve 0.11 0.15 mm

Measurement steps:Rotate the crankshaft counterclockwise toalign the slit a on the rotor with the station-ary pointer b on the crankcase cover (left)when the piston is Top Dead Center (TDC).

Measure the valve clearance by using a feel-er gauge.Out of specification Adjust clearance.

3-5

A B

VALVE CLEARANCE ADJUSTMENT/IDLING SPEED ADJUSTMENT

INSPADJ

***************************************

14 Nm (1.4 mkg)

***************************************

10 Nm (1.0 mkg)

New

10 Nm (1.0 mkg)

New

18 Nm (1.8 mkg)

5. Adjust:Valve clearance

Adjustment steps:Loosen the locknut 1 .Turn the adjuster 3 in or out with the valve ad-justing tool 2 until specified clearance is ob-tained.

Turning in Valve clearance is decreased.

Turning out Valve clearance is increased.

Valve adjusting tool:90890-01311

Hold the adjuster to prevent it from moving andtighten the locknut.

Measure the valve clearance. If the clearance is incorrect, repeat abovesteps until specified clearance is obtained.

6. Install:Valve cover (intake side) 1

O-ring 2 Valve cover (exhaust side) 3

O-ring 4 A Intake side

B Exhaust side

7. Install:Spark plugTiming check window screw 1(with O-ring)

Center plug 2(with O-ring)

YP303022

IDLING SPEED ADJUSTMENT1. Start the engine and let it warm up for several

minutes.2. Attach: Inductive tachometer to the spark plug lead.

Inductive tachometer:90890-03113

3-6

IDLING SPEED ADJUSTMENT/THROTTLE CABLE ADJUSTMENT

INSPADJ

***************************************

***************************************

NOTE:

***************************************

NOTE:

3. Check:Engine idling speedOut of specification Adjust.

Engine idling speed:1,250 1,350 r/min

4. Adjust:Engine idle speed

Adjustment steps:Turn the pilot screw 1 until it is lightly seated.Turn the pilot screw out by the specified num-ber of turns.

Pilot screw:2 turns out

Turn the throttle stop screw 2 in or out until thespecified idling speed is obtained.

Turning in Idling speed is increased.

Turning out Idling speed is decreased.

5. Adjust:Throttle cable free playRefer to “THROTTLE CABLE ADJUST-MENT” section.

YP303032

THROTTLE CABLE ADJUSTMENT

Prior to adjusting the throttle cable free play, theengine idling speed should be adjusted.

1. Check:Throttle cable free play aOut of specification Adjust.

Free play (throttle cable):3 5 mm at throttle grip flange

2. Adjust:Throttle cable free play

Adjustment steps:

Never accelerate the throttle when stopping theengine.

3-7

THROTTLE CABLE ADJUSTMENT/SPARK PLUG INSPECTION

INSPADJ

WARNING

***************************************

CAUTION:

Loosen the locknut 1 on the throttle cable.Turn the adjuster 2 in or out until specifiedfree play is obtained.

Turning in Free play is increased.

Turning out Free play is decreased.

Tighten the locknut.

After adjusting, turn the handlebar to theright and to the left to ensure that this doesnot cause the engine idling speed tochange.

EB303040

SPARK PLUG INSPECTION1. Remove:Spark plug capSpark plug

Before removing the spark plug, use com-pressed air to blow away any dirt accumu-lated in the spark plug wells to prevent itfrom falling into the cylinder.

1. Check:Spark plug typeIncorrect Replace.

Standard spark plug:DR8EA (NGK)

2. Inspect:Electrode 1Wear/damage Replace.

Insulator 2Abnormal color Replace.Normal color is a medium-to-light tan color.

3. Clean:Spark plug(with spark plug cleaner or wire brush)

4. Measure:Spark plug gap a(with a wire gauge)Out of specification Adjust gap.

Spark plug gap:0.6 0.7 mm

3-8

SPARK PLUG INSPECTION/IGNITION TIMING CHECK

INSPADJ

18 Nm (1.8 mkg)

NOTE:

NOTE:

***************************************

***************************************NOTE:

5. Install:Spark plug

Before installing a spark plug, clean the gasketsurface and plug surface.

YP303052

IGNITION TIMING CHECK

Prior to checking the ignition timing, check allelectrical connections related to the ignitionsystem. Make sure all connections are tight andfree of corrosion and that all ground connec-tions are tight.

1. Remove:Timing check plug

2. Attach:Timing light 1Engine tachometer 2(to the spark plug lead)

Timing light:90890-03141

Engine tachometer:90890-03113

3. Check: Ignition timing

Checking steps:Start the engine and let it warm up for severalminutes. Let the engine run at the specifiedspeed.

Engine idling speed:1,250 1,350 r/min

Visually check the stationary pointer a toverify it is within the required firing range b in-dicated on the flywheel.Incorrect firing range Check the ignitionsystem.

Ignition timing is not adjustable.

3. Install:Timing check plug

3-9

COMPRESSION PRESSURE MEASUREMENTINSPADJ

NOTE:

CAUTION:

SR303060

COMPRESSION PRESSURE MEASUREMENT

Insufficient compression pressure will result inperformance loss.

1. Check:Valve clearanceOut of specification Adjust.Refer to “VALVE CLEARANCE ADJUST-MENT” section.

2. Start the engine and let it warm up for severalminutes.

3. Turn off the engine.4. Remove:Spark plug

Before removing the spark plug, use com-pressed air to blow away any dirt accumu-lated in the spark plug well to prevent it fromfalling into the cylinder.

5. Attach:Compression gauge 1

Compression gauge:90890-03081

Adaptor:90890-04082

6. Measure:Compression pressureIf it exceeds the maximum pressure allowed Inspect the cylinder head, valve surfacesand piston crown for carbon deposits.If it is below the minimum pressure Squirta few drops of oil into the affected cylinderand measure again.Follow the table below.

Compression pressurep p(With oil applied into cylinder)

Reading Diagnosis

Higher thanwithout oil

Worn or damaged pistons

Same aswithout oil

Possible defective ring(s),valves, cylinder head gas-ket or piston Repair.

3-10

COMPRESSION PRESSURE MEASUREMENT/ENGINE OIL LEVEL INSPECTION

INSPADJ

***************************************

WARNING

18 Nm (1.8 mkg)

NOTE:

Compression pressure (at sea lev-el):Standard:

1,200 kPa (12.0 Kg/cm 2, 12 bar)Minimum:

1,100 kPa (11.0 Kg/cm 2, 11 bar)

Measurement steps:Crank the engine with the throttle wideopenuntil the reading on the compression gaugestabilizes.

Before cranking the engine, ground allspark plug leads to prevent sparking.

7. Install:Spark plug

YP303070

ENGINE OIL LEVEL INSPECTION1. Stand the motorcycle on a level surface.

Make sure the motorcycle is upright when in-specting the oil level.

2. Start the engine and let it warm up for a fewminutes.

3. Turn off the engine.4. Inspect:Engine oil levelOil level should be between maximum 1and minimum 2 marks.Oil level is below the minimum mark Add oil up to the proper level.

RECOMMENDED ENGINE OILRefer to the chart for selection of the oils suitedto the atomosperic temperature.

Recommended oil:Refer to the following chart forselection of oils which are suitedto the atmospheric temperatures.

Recommended engine oil classifica-tion:

API STANDARD:API “SE” or higher grade

3-11

ENGINE OIL LEVEL INSPECTION/ENGINE OIL REPLACEMENT

INSPADJ

CAUTION:

NOTE:

***************************************

***************************************

Do not put in any chemicals additives oruse oils with a grade of CD a or higher.

Be sure not to use oils labeled “ENERGYCONSERVING II” b or higher. Engine oilalso lubricates the clutch and additivescould cause clutch slippage.

Be sure no foreign material enters thecrankcase.

5. Start the engine and let it warm up for a fewminutes.

6. Turn off the engine and inspect the oil levelonce again.

Wait a few minutes until the oil settles before in-specting the oil level.

SR303082

ENGINE OIL REPLACEMENT1. Start the engine and let it warm up for several

minutes.2. Turn off the engine and place a container un-

der the engine.3. Remove:Oil filler plug 1Drain plug 2Drain the crankcase of its oil.

4. Loosen:Bolt 1 (oil filter cover-lower)

5. Drain the crankcase of its oil.If the oil filter is to be replaced during this pro-cedure, remove the following parts and rein-stall them afterwards.

Replacement steps:Remove the oil filter cover 1 and oil filter ele-ment 2 .

Check the O-ring 3 . If it is cracked or dam-aged, replace it.

Install the oil filter element and oil filter cover.

Screw:7 Nm (0.7 mkg)

Bolt:10 Nm (1.0 mkg)

3-12

ENGINE OIL REPLACEMENTINSPADJ

43 Nm (4.3 mkg)

NOTE:

CAUTION:

***************************************

***************************************

6. Install:Drain plug

Inspect the O-ring. If it is damaged, replace itwith a new one.

Before reinstalling the drain plug, do not for-get to fit the O-ring, compression spring andoil strainer. Be sure you fit each item in thecorrect position and order.

7. Fill:Crankcase

Oil quantity:With oil filter change 1.1 LWithout oil filter change 1.0 L

Refer to “ENGINE OIL LEVEL INSPECTION”section.

8. Inspect:Oil flow

Inspection steps:Slightly loosen the oil check bolt 1 .Start the engine and keep it idling until the oilbegins to seep from the oil check bolt.If no oil comes out after one minute, turn theengine off so it will not seize.

Check oil passages and oil pump for damageor leakage.

Start the engine after solving the problem(s),and recheck the oil pressure.

Tighten the oil check bolt to specification.

Oil check bolt:7 Nm (0.7 mkg)

3-13

TIMING CHAINE TENSIONER ADJUSTMENT/CLUTCH ADJUSTMENT

INSPADJ

***************************************

***************************************5 Nm (0.5 mkg)

SR*******

TIMING CHAINE TENSIONER ADJUSTMENT1. Remove:Cap 1

2. Check:RodCheck the rod end 1 is flush with the adjust-er end 2 .Not flush Adjust.

3. Adjust:Timing chine tension

Adjustment steps:Loosen the locknut 1 .Turn the adjuster 2 in or out until the rod end

3 is flush with the adjuster end.Tighten the locknut 1 .

Locknut:30 Nm (3.0 mkg)

4. Install:Cap

EB303093

CLUTCH ADJUSTMENT1. Check:Clutch cable free play aOut of specification Adjust.

Free play (clutch lever):10 15 mm at clutch lever end

3-14

CLUTCH ADJUSTMENT/AIR FILTER CLEANING

INSPADJ

***************************************

NOTE:

***************************************

CAUTION:

2. Adjust:Clutch cable free play

Adjustment steps:Crankcase sideMake sure that the adjuster 1 and locknut 2are fully tightened.

Loosen the locknut 2 .Turn the adjuster 1 in or out until the specifiedfree play is obtained.

Turning in Free play is decreased.

Turning out Free play is increased.

Tighten the locknut 2 .

If the amount of free play is still incorrect, adjustthe clutch cable free play with the other adjuster(on the clutch lever holder).

Lever sideLoosen the locknut 3 .Turn the adjuster 4 in or out until the specifiedfree play is obtained.

Turning in Free play is increased.

Turning out Free play is decreased.

Tighten the locknut 3 .

SR303123

AIR FILTER CLEANING1. Remove:Side cover (right)Air filter element holderAir filter element 1Plate 2

Never operate the engine without the air fil-ter element installed. Unfiltered air willcause rapid wear of engine parts and maydamage the engine. Operating the enginewithout the filter element will also affect thecarburetor tuning, leading to poor engineperformance and possible overheating.

3-15

AIR FILTER CLEANING/EXHAUST SYSTEM INSPECTION

INSPADJ

NOTE:

CAUTION:

WARNING

2. Inspect:Air filter element 1Damage Replace.

3. Clean:Air filter elementUse solvent to clean the element.

After cleaning, remove the remaining solvent bysqueezing the element.

Do not twist the filter element when squeez-ing it.

Never use low flash point solvents such asgasoline to clean the air filter element. Suchsolvents may cause a fire or an explosion.

4. Apply the recommended oil to the entire sur-face of the filter and squeeze out the excessoil. The element should be wet but not drip-ping.

Recommended oil:Engine oil

5. Install:Plate 1Air filter element 2Air filter element holderSide cover (right)

T******

EXHAUST SYSTEM INSPECTION1. Inspect:Exhaust pipe 1Muffler 2Crack/Damage Replace.

Gasket 3Exhaust gas leaks Replace.

3-16

EXHAUST SYSTEM INSPECTIONINSPADJ

1

2

2. Check:Tightening torque

Bolt :12 Nm (1.2 mkg)

Nut :20 Nm (2.0 mkg)

3-17

FRONT BRAKE ADJUST MENT/REAR BRAKE ADJUSTMENT

INSPADJ

***************************************

CAUTION:

WARNING

***************************************

EB304002

CHASSISFRONT BRAKE ADJUSTMENT1. Check:Brake lever free play aOut of specification Adjust.

Free play (Brake lever):2 5 mm at brake lever end

2. Adjust:Brake lever free play

Adjustment steps:Loosen the locknut 1 .Turn the adjuster 2 in or out until the specifiedfree play is obtained.




Make sure that there is no brake drag afteradjusting the front brake lever free play.

A soft or spongy feeling in the brake levercan indicate the presence of air in the brakesystem. This air must be removed by bleed-ing the brake system before the motorcycleis operated. Air in the brake system will con-siderably reduce braking performance andcould result in loss of control and possiblyan accident. Inspect and bleed the brakesystem if necessary.

NB304012

REAR BRAKE ADJUSTMENT1. Check:Brake pedal height aOut of specification Adjust.

Brake pedal height:0 mmbelow the top of the footrest

3-18

REAR BRAKE ADJUSTMENTINSPADJ

***************************************

***************************************

***************************************

CAUTION:

***************************************

2. Adjust:Brake pedal height

Adjustment steps:Loosen the locknut 1 .Turn the adjuster 2 in or out until the specifiedpedal height is obtained.

Turning in Pedal height is decreased.

Turning out Pedal height is increased.


3. Check:Brake pedal free play aOut of specification Adjust

Free play (Brake pedal):20 30 mm at brake lever end

4. Adjust:Brake pedal free play

Adjustment steps:Turn the adjuster 1 in or out until the specifiedfree play is obtained.



Make sure that there is no brake drag afteradjusting the brake pedal height and thefree play.

5. Adjust:Brake light switchRefer to “BRAKE LIGHT SWITCH ADJUST-MENT”.

3-19

BRAKE FLUID LEVEL INSPECTIONINSPADJ

NOTE:

NOTE:

CAUTION:

WARNING

EB304020

BRAKE FLUID LEVEL INSPECTION1. Stand the motorcycle on a level surface.

Make sure the motorcycle is upright when in-specting the brake fluid level.

Stand the motorcycle on its centerstand if ithas one. If not, place a suitable stand underthe motorcycle.

2. Inspect:Brake fluid levelBrae fluid level is below the “LOWER” levelline a Fill to proper level.

Recommended brake fluid:DOT #4 or DOT #3

For a correct reading of the brake fluid level,make sure the top of the handlebar brake fluidreservoir is horizontal.

Brake fluid may corrode painted surfaces orplastic parts. Always clean up any spilt fluidimmediately.

Use only the designated brake fluid. Otherfluids may deteriorate the rubber seals,causing leakage and poor brake perfor-mance.

Refill with the same type of fluid. Mixingfluids may result in a harmful chemicalreaction leading to poor brake perfor-mance.

Be careful that water does not enter thebrake fluid reservoir during refilling. Waterwill significantly lower the boiling point ofthe fluid and may cause vapour lock.

3-20

BRAKE PAD INSPECTION/BRAKE SHOE INSPECTION/BRAKE LIGHT SWITCH ADJUSTMENT

INSPADJ

NOTE:

***************************************

***************************************

EB304030

BRAKE PAD INSPECTION1. Operate the brake lever.2. Inspect:Brake pad (front)Wear indicators 1 almost touch the brakedisc Replace the brake pads as a set.Refer to “FRONT BRAKE” in CHAPTER 6.

EB304040

BRAKE SHOE INSPECTION1. Operate the brake pedal.2. Inspect:Brake shoesWear indicator 1 reaches the wear limit line2 Replace the brake shoes as a set.Refer to “REAR WHEEL” in CHAPTER 6.

EB304050

BRAKE LIGHT SWITCH ADJUSTMENT

The brake light switch is operated by move-ment of the brake pedal.

Adjustment is correct when the brake lightcomes on just before the braking effect actual-ly starts.

1. Check:Brake light operation timing Incorrect Adjust.

2. Adjust:Brake light operating timing

Adjustment steps:Hold the main body 1 of the switch with yourhand so that it does not rotate, and turn the ad-juster 2 in or out until the proper operationtiming is obtained.

Turning in Brake light comes on fast.

Turning out Brake light comes on slows.

3-21

AIR BLEEDINGINSPADJ

WARNING

***************************************

NOTE:

EB304070

AIR BLEEDING(HYDRAULIC BRAKE SYSTEM)

Bleed the brake system whenever:The system is disassembled.A brake hose is loosened or removed.The brake fluid level is very low.Brake operation is faulty.Loss of braking performance may occur ifthe brake system is not properly bled.

1. Bleed:Brake system

Air bleeding steps:a. Fill the reservoir with the proper brake fluid.b. Install the diaphragm. Be careful not to spill

any fluid or allow the reservoir to overflow.c. Connect a clear plastic hose 1 tightly to the

caliper bleed screw 2 .d. Place the other end of the hose into a con-

tainer.e. Slowly apply the brake lever several times.f. Pull the lever in. Hold the lever in position.g. Loosen the bleed screw and allow the lever

to travel towards its limit.h. Tighten the bleed screw when the lever limit

has been reached, then release the lever.i. Repeat steps (e) to (h) until all air bubbles

have disappeared from the brake fluid.

When bleeding the brake system, make surethat there is always enough brake fluid in thebrake fluid reservoir before applying the brakelever. Ignoring this precaution could allow air toenter the brake system, considerably lengthen-ing the bleeding procedure.

3-22

AIR BLEEDING/DRIVE CHAIN SLACK ADJUSTMENT

INSPADJ

NOTE:

WARNING

***************************************

NOTE:

CAUTION:

WARNING

j. Tighten the bleed screw.

Bleed screw:6 Nm (0.6 mkg)

If bleeding is difficult, it may be necessary to letthe brake fluid settle for a few hours.Repeat the bleeding procedure when the tinybubbles in the brake system have disappeared.

k. Fill the brake fluid reservoir to the proper lev-el.Refer to “BRAKE FLUID LEVEL INSPEC-TION”.

Check brake operation after bleeding thebrake system.

SR304093

DRIVE CHAIN SLACK ADJUSTMENT

Before checking and adjusting, rotate the rearwheel several revolutions and check the slackat several points to find the tightest point. Checkand if necessary adjust the drive chain slackwith the rear wheel in this “tightest” position.

Too little chain slack will overload the en-gine and other vital parts; keep the slackwithin the specified limits.

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

Stand the motorcycle on its centerstand.

3-23

A B

DRIVE CHAIN SLACK ADJUSTMENTINSPADJ

***************************************

NOTE:

***************************************

CAUTION:

1. Check:Drive chain slackOut of specification Adjust.

Drive chain slack:25 35 mm

a Check window

b Adjustable limit

c Usable limit

d Usable range2. Adjust:Drive chain slack

A Standard

B Useful limit

Adjustment steps:Loosen the axle nut 1 .Turn the chain adjusters 2 clockwise or coun-terclockwise until the specified drive chainslack is obtained.

Clockwise Chain slack is decreased.

Counter-clockwise

Chain slack is increased.

Turn each chain adjuster exactly the sameamount to maintain correct axle alignment.(There are marks e on each chain adjuster.Use them when adjusting the slack for properalignment.)

Before tightening the axle nut to specification,make sure that there is no clearance at the ad-juster (or the swingarm end) on both sides bypushing the wheel forward.

Rear wheel axle:65 Nm (6.5 mkg)

Do not adjust the drive chain slack abovethe usable range b of check window a .

3-24

STEERING HEAD INSPECTIONINSPADJ

WARNING

NOTE:

***************************************

NOTE:

***************************************

SR304130

STEERING HEAD INSPECTION


1. Stand the motorcycle on a level surface.

Stand the motorcycle on its centerstand.

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

3. Check:Steering assembly bearingsGrasp the bottom of the lower front fork tubesand gently rock the fork assembly.Looseness Adjust the steering head.

4. Adjust:Steering head

Adjustment steps:Tighten the ring nut 1 using the ring nutwrench 2 .

Loosen the ring nut completely, then tighten it.

When tighten the ring nut, should be steady theball bearings and steering shaft movingsmoothly.

Ring nut wrench:90890-01403

Steering ring nut:1st step: 38 Nm (3.8 mkg)2nd step: 7 Nm (0.7 mkg)

Check the steering head for looseness or bind-ing by turning it all the way in both directions.

3-25

FRONT FORK INSPECTION/REAR SHOCK ABSORBER ADJUSTMENT

INSPADJ

WARNING

WARNING

***************************************

a

b

EB304140

FRONT FORK INSPECTION


1. Stand the motorcycle on a level surface.2. Check: Inner tubeScratches/damage Replace.

Oil sealExcessive oil leakage Replace.Hold the motorcycle upright and apply thefront brake.

3. Check:OperationPush down hard on the handlebars severaltimes.Unsmooth operation Repair.Refer to “FRONT FORK” in CHAPTER 6.

YP304160

REAR SHOCK ABSORBER ADJUSTMENT

Always adjust each rear shock absorberpreload to the same setting. Uneven ad-justment can cause poor handling and lossof stability.

Securely support the scooter so there is nodanger of it falling over.

1. Adjust:Spring preloadTurn the adjuster ring 1 to direction a or b .

Adjustment steps:Turn the adjuster ring in or out.

Turning toward Spring preload isincreased.

Turning toward Spring preload isdecreased.

3-26

REAR SHOCK ABSORBER ADJUSTMENT/TIRE INSPECTION

INSPADJ

CAUTION:

***************************************

WARNING

Adjustment numbers:

Standard 1

Minimum 1

Maximum 5

Never turn the adjuster beyond the maxi-mum or minimum setting.

Always adjust each shock absorber to thesame setting.

EB304171

TIRE INSPECTION1. Measure:Tire inflation pressureOut of specification Adjust.

Tire inflation pressure should only bechecked and adjusted when the tire tem-perature equals the ambient air tempera-ture. Tire inflation pressure and suspen-sion must be adjusted according to thetotal weight of the cargo, rider, passengerand accessories (fairing, saddlebags, etc.if approved for this model), and accordingto whether the motorcycle will be operatedat high speed or not.NEVER OVERLOAD THE MOTORCYCLE.

Operation of an overloaded motorcyclecould cause tire damage, accident or inju-ry.

Basic weight:With oil andfull fuel tank

113 kg

Maximum load* 164 kg

Cold tire pres-sure

Front Rear

Up to 90 kgload*

175 kPa(1.75 kg/cm 2,

1.75 bar)

200 kPa(2.0 kg/cm 2,

2.0 bar)

90 kg maximum. load*

175 kPa(1.75 kg/cm 2,

1.75 bar)

25 kPa(2.25 kg/cm 2,

2.25 bar)

* Load is the total weight of the cargo, rider, pas-senger and accessories.

3-27

TIRE INSPECTIONINSPADJ

WARNING

WARNING

2. Inspect:Tire surfacesWear/damage Replace.

Minimum tire tread depth(front and rear): 1.6 mm

1 Tread depth2 Side wall3 Wear indicator

It is dangerous to ride with a worn-out tire.When the tire tread begins to show signs ofwear, replace the tire immediately.

Patching a punctured tube is not recom-mended. If it is absolutely necessary to doso, use great care and replace the tube assoon as possible with a good quality re-placement tube.

Do not use tubeless tires on a wheel de-signed for tube type tires only. Tire failureand personal injury may result from sud-den deflation.

Tube type wheel Tube type tire only

T beless type wheel

Tube type orTubeless type wheel

yptubeless tire.

Be sure to install the correct tube when us-ing tube type tires.

After extensive tests, the tires listed belowhave been approved by Yamaha Motor Co.,Ltd. for this model. No guarantee concern-ing handling characteristics can be given ifa tire combination other than one ap-proved by Yamaha is used on this motor-cycle. The front and rear tires should al-ways be by the same manufacturer and ofthe same design.

After mounting a tire, ride conservatively fora while to give the tire time to seat itselfproperly in the rim. Failure to do so couldlead to an accident with possible injury tothe rider or damage to the motorcycle.

2. After a tire repair or replacement, be sure totighten the valve stem locknut 1 to specifi-cation.

Locknut:1.5 Nm (0.15 mkg)

3-28

SPOKE INSPECTION AND TIGHTENING/WHEEL INSPECTION

INSPADJ

NOTE:

NOTE:

WARNING

EB304190

SPOKE INSPECTION AND TIGHTENING1. Inspect:Spokes 1Bending/damage Replace.Loose spoke Retighten.

2. Tighten:Spokes

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

Nipple:2 Nm (0.2 mkg)

EB304180

WHEEL INSPECTION1. Inspect:WheelsDamage/Bends Replace.

Always balance the wheel when a tire or wheelhas been changed or replaced.

Never attempt to make any repairs to thewheel.

3-29

BATTERY INSPECTIONINSPADJ

CAUTION:

NOTE:

CAUTION:

EB305001

ELECTRICALBATTERY INSPECTION1. Remove:Side covers (left and right)Refer to “SIDE COVER, SEAT AND FUELTANK” section.

2. Inspect:Electrolyte levelElectrolyte level should be between the up-per 1 and lower 2 level marks.Electrolyte level is too low Add electrolyteto proper level.

Refill with distilled water only. Tap watercontains minerals which are harmful to abattery.

3. Inspect:Battery terminalsDirt Clean with a wire brush.Poor connection Correct.

After cleaning the terminals, apply a light coat ofgrease to the terminals.

4. Inspect:Breather hoseObstruction Remove.Damage Replace.

When inspecting the battery, make sure thatthe breather hose is routed correctly. If thebreather hose is positioned in such a way asto allow battery electrolyte or gas to comeinto contact with the frame, this could dam-age the motorcycle and ruin its finish.

5. Connect:Breather hose 1Make sure that the hose is properly attachedand routed.

6. Check:Specific gravityLess than 1.280 Recharge the battery.

Charging Current:0.7 amps/10 hrs

Specific Gravity:1.280 at 20C

3-30

BATTERY INSPECTIONINSPADJ

***************************************

***************************************CAUTION:

WARNING

Replace the battery if:Battery voltage will not rise to a specific valueor bubbles fail to rise during charging.

Sulphation of one or more cells occurs, (as in-dicated by the plates turning white, or materialaccumulating in the bottom of the cell).

Specific gravity readings after a long, slowcharge indicate that one cell is charged lowerthan the rest.

Warpage or buckling of plates or insulators isevident.

Always charge a new battery before using itto ensure maximum performance.

Battery electrolyte is dangerous. It containssulfuric acid which is poisonous and highlycaustic.Always follow these preventive measures:Avoid bodily contact with electrolyte as itcan cause severe burns and permanenteye injury.

Wear protective eye gear when handling orworking near batteries.

Antidote (EXTERNAL):SKIN – Flush with water.EYES – Flush with water for 15 minutes andget immediate medical attention.

Antidote (INTERNAL):Drink large quantities of water or milk fol-lowed with milk of magnesia, beaten egg orvegetable oil. Get immediate medicalattention.

Batteries generate explosive hydrogengas.

Always follow these preventive measures:Charge batteries in a well – ventilated area.Keep batteries away from fire, sparks oropen flames (e.g., welding equipment,lighted cigarettes, etc.)

DO NOT SMOKE when charging or han-dling batteries.

KEEP BATTERIES AND ELECTROLYTE OUTOF REACH OF CHILDREN.

3-31

BATTERY INSPECTION/FUSE INSPECTIONINSPADJ

CAUTION:

CAUTION:

***************************************

NOTE:

***************************************

7. Install:Battery

8. Connect:Battery leads

Connect the positive lead 1 first and thenconnect the negative lead 2 .

9. Connect:Breather hoseBe sure the hose is properly attached androuted.Refer to “CABLE ROUTING” section.

10. Install:Side covers (left and right)Refer to “SIDE COVER, SEAT AND FUELTANK” section.

T305010

FUSE INSPECTION

Always turn off the main switch whenchecking or replacing the fuse. Otherwise, ashort circuit may occur.

1. Remove:Side covers (left and right)Refer to “SIDE COVER, SEAT AND FUELTANK” section.

Fuse holder 12. Inspect:Fuse

Inspection steps:Connect the pocket tester to the fuse andcheck it for continuity.

Set the tester selector to “Ω 1” position.

Pocket tester:90890-03112

If the tester is indicated at ∞. Replace thefuse.

3-32

FUSE INSPECTION/HEADLIGHT BEAM ADJUSTMENT

INSPADJ

***************************************

WARNING

***************************************

3. Replace:Blown fuse

Replacement steps:Turn off the main switch. Install a new fuse with the proper current rat-ing.

Turn on switches to verify operation of relatedelectrical devices.

If the fuse blows again immediately, check theelectrical circuit.

Never use a fuse with a rating other than thatspecified. Never use other materials in placeof a fuse. An improper fuse may cause ex-tensive damage to the electrical system,malfunction of lighting and ignition systemsand could possibly cause a fire.

4. Install:Fuse holderSide cover (left and right)Refer to “SIDE COVER, SEAT AND FUELTANK” section.

EB305022

HEADLIGHT BEAM ADJUSTMENT1. Adjust:Headlight beam (vertical)Loosen the bolt 1 and adjust the headlightunit.

CHAPTER 4.ENGINE OVERHAUL

ENGINE REMOVAL 4-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . EXHAUST PIPE, STARTING MOTOR AND WIRE READ 4-1. . . . . . . . . CARBURETOR, CLUTCH CABLE AND DRIVE CHAIN 4-2. . . . . . . . . . ENGINE 4-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CYLILNDER HEAD 4-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CAM SPROCKET COVER 4-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CYLINDER HEAD 4-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CYLINDER HEAD REMOVAL 4-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CYLINDER HEAD INSPECTION 4-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CYLINDER HEAD INSTALLATION 4-8. . . . . . . . . . . . . . . . . . . . . . . . . . . .

CAM SHAFT AND ROCKER ARMS 4-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ROCKER ARM AND ROCKER ARM SHAFT REMOVAL 4-11. . . . . . . . . CAMSHAFT INSPECTION 4-11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ROCKER ARMS AND ROCKER ARM SHAFTS INSPECTION 4-12. . . . CAMSHAFT AND ROCKER ARM INSTALLATION 4-12. . . . . . . . . . . . . .

VALVES AND VALVE SPRINGS 4-14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VALVES AND VALVE SPRINGS REMOVAL 4-15. . . . . . . . . . . . . . . . . . . . VALVES AND VALVE GUIDES 4-15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VALVE SEATS INSPECTION 4-17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VALVES AND VALVE SPRINGS INSTALLATION 4-18. . . . . . . . . . . . . . . .

CYLINDER AND PISTON 4-20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PISTON AND PISTON RINGS REMOVAL 4-21. . . . . . . . . . . . . . . . . . . . . . CYLINDER AND PISTON INSPECTION 4-21. . . . . . . . . . . . . . . . . . . . . . . PISTON RING INSPECTION 4-23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PISTON PIN INSPECTION 4-24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PISTON RINGS, PISTON AND CYLINDER INSTALLATION 4-24. . . . . .

CLUTCH 4-26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CRANKCASE COVER (RIGHT) 4-26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CLUTCH 4-27. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CLUTCH REMOVAL 4-29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CLUTCH INSPECTION 4-29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PUSH ROD INSPECTION 4-30. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CLUTCH INSTALLATION 4-30. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

OIL PUMP 4-33. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PRIMARY DRIVE GEAR REMOVAL 4-35. . . . . . . . . . . . . . . . . . . . . . . . . . . OIL PUMP INSPECTION 4-35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OIL DELIVERY PASSAGE INSPECTION

(CRANK CASE COVER (right)) 4-35. . . . . . . . . . . . . . . . . . . . . . . . . . . . OIL PUMP INSTALLATION 4-36. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PRIMARY DRIVE GEAER INSTALLATION 4-36. . . . . . . . . . . . . . . . . . . . .

BALANCER GEAR 4-37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BALANCER DRIVEN GEAR REMOVAL 4-38. . . . . . . . . . . . . . . . . . . . . . . DRIVE GEAR INSPECTION 4-38. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BALANCER DRIVE GEAR ASSEMBLY 4-38. . . . . . . . . . . . . . . . . . . . . . . . BALANCER GEAR INSTALLATION 4-39. . . . . . . . . . . . . . . . . . . . . . . . . . .

SHIFT SHAFT AND SEGMENT 4-40. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SHIFT SHAFT REMOVAL 4-42. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SHIFT SHAFT INSPECTION 4-42. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SEGMENT INSTALLATION 4-42. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SIFT SHAFT INSTALLATION 4-43. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CDI MAGNETO AND STARTER CLUTCH 4-44. . . . . . . . . . . . . . . . . . . . . . . . CRANKCASE COVER (LEFT) 4-44. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PICKUP COIL AND STATOR COIL 4-45. . . . . . . . . . . . . . . . . . . . . . . . . . . . CDI MAGNETO AND STARTER CLUTCH 4-46. . . . . . . . . . . . . . . . . . . . . . CDI MAGNETO REMOVAL 4-47. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . STARTER CLUTCH INSPECTION 4-47. . . . . . . . . . . . . . . . . . . . . . . . . . . . STARTER CLUTCH INSTALLATION 4-48. . . . . . . . . . . . . . . . . . . . . . . . . . CDI MAGNETO INSTALLATION 4-48. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CRANK CASE AND CRANKSHAFT 4-50. . . . . . . . . . . . . . . . . . . . . . . . . . . . . CRANKCASE 4-50. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CRANKSHAFT AND BALANCER WEIGHT 4-52. . . . . . . . . . . . . . . . . . . . . CRANKCASE SEPARATION 4-53. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PLUNGER SEAL REMOVAL 4-53. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CRANKSHAFT INSPECTION 4-54. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PLUNGER SEAL INSTALLATION 4-55. . . . . . . . . . . . . . . . . . . . . . . . . . . . . BALANCER WEIGHT INSTALLATION 4-55. . . . . . . . . . . . . . . . . . . . . . . . . CRANKCASE INSTALLATION 4-55. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TRANSMISSION, SHIFT CAM AND SHIFT FORK 4-56. . . . . . . . . . . . . . . . . DRIVE AXLE AND MAIN AXLE 4-57. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TRANSMISSION, SHIFT CAM AND SHIFT FORK REMOVAL 4-58. . . . SHIFT FORK SHIFT CAM INSPECTION 4-58. . . . . . . . . . . . . . . . . . . . . . . TRANSMISSION, SHIFT CAM AND SHIFT FORK INSTALLATION 4-59

4-1


1234567

Exhaust pipe, starting motor andwire read removalSide cover, seat and fuel tank

Rear foot rest (right)Exhaust pipe Ass’yExhaust pipe gasketGround leadStarting motor readCDI magneto readPlug cap

1111111

Refer to “SIDE COVER, SEAT AND FUEL TANK” section in CHAPTER 3.


Reverse the removal procedure forinstallation.

12 Nm (1.2 mkg)

20 Nm (2.0 mkg)

ENGINE REMOVAL ENG

EB400000

ENGINE OVERHAULENGINE RE MOVALEXHAUST PIPE, STARTING MOTOR AND WIRE READ

4-2

ENGINE REMOVAL ENG


12345

67

Carburetor, clutch cable and drivechain removalCarburetor

Clutch cableCrankcase breather hoseShift pedalDrive sprocket coverRear wheel axle nut

Sprocket holderDrive sprocket/drive chain

11111

11/1


Loosen the axle nut and slacken the drive chain.

NOTE:

Refer to “CARBURETOR” section in CHAPTER 5.


10 Nm (1.0 mkg)

65 Nm (6.5 mkg)

8 Nm (0.8 mkg)

7 Nm (0.7 mkg)

CARBURETOR, CLUTCH CABLE AND DRIVE CHAIN

4-3

ENGINE REMOVAL ENG


12345

Engine removal

Engine stay (top)Front engine stayEngine mount bolt (rear upper)Engine mount bolt (rear under)Engine

11111

Remove the parts in order.Securely support the motorcycle so there is no danger of it falling over.


33 Nm (3.3 mkg)

33 Nm (3.3 mkg)

33 Nm (3.3 mkg)

33 Nm (3.3 mkg)

33 Nm (3.3 mkg)

ENGINE

4-4

CYLINDER HEAD ENG


1234567

Cam sprocket cover removalSide cover, seat and fuel tank

Exhaust pipe assembly

Carburetor assembly

Engine stay (top)

Spark plugCam sprocket cover/O-ringValve cover (intake side)/O-ringValve cover (exhaust side)/O-ringCarburetor joint/O-ringTiming mark cap/O-ringCenter cap/O-ring

11/11/11/11/11/11/1


Refer to “SIDE COVER SEAT AND FUEL TANK REMOVAL” section in CHAPTER 3.Refer to “ENGINE REMOVAL” section inCHAPTER 4.Refer to “CARBURETOR” section in CHAPTER 5.Refer to “ENGINE REMOVAL” section inCHAPTER 4.


10 Nm (1.0 mkg)

2 Nm (0.2 mkg)

7 Nm (0.7 mkg)

10 Nm (1.0 mkg)

18 Nm (1.8 mkg)

CYLINDER HEADCAM SPROCKET COVER

4-5

CYLINDER HEAD ENG


12345678

Cylinder head removalTiming chain tensioner cap/O-ringTiming chain tensioner assemblyCam sprocket/Timing chainIgnition coilCylinder headDowel pinsGasketCylinder head gasket

1/11

1/111311


Refer to “CYLINDER HEAD REMOVAL/INSTALLATION” section.

Refer to “CYLINDER HEAD INSTALLATION” section.


22 Nm (2.2 mkg)

20 Nm (2.0 mkg)

5 Nm (0.5 mkg)

60 Nm (6.0 mkg)

30 Nm (3.0 mkg)

CYLINDER HEAD

4-6

CYLINDER HEAD ENG

NOTE:

NOTE:

T401030

CYLINDER HEAD REMOVAL1. Align:Slit a on the magneto(with stationary pointer b on the crank casecover)

Turn the crank shaft counterclockwise with a wrench and align the “I” mark c with the cylinder head match mark d when the piston isat TDC on the compression stroke.

2. Loosen:Cam sprocket bolt 1

3. Remove:Timing chain tensioner assembly 1

4. Remove:Cam sprocket boltCam sprocket 1Timing chain 2

Fasten a safety wire to the timing chain to prevent it from falling into the crankcase.

4-7

CYLINDER HEAD ENG

NOTE:

NOTE:

***************************************

NOTE:

***************************************

5. Remove:Cylinder head

Loosen the nuts in their proper loosening sequence.

Start by loosening each nut 1/2 turn until all are loose.

YP402000

CYLINDER HEAD INSPECTION1. Eliminate:Carbon deposits(from combustion chambers)Use a rounded scraper.

Do not use a sharp instrument to avoid damaging or scratching:Spark plug threadsValve seats

2. Inspect:Cylinder headScratches/damage Replace.

3. Measure:Cylinder head warpageOut of specification Resurface.

Cylinder head warpage:Less than 0.03 mm

Warpage measurement and resurfacementsteps:Place a straightedge and a feeler gaugeacross the cylinder head.

Measure the warpage.If the warpage is out of specification, resurfacethe cylinder head.

Place a 400 600 grit wet abrasive paper onthe surface plate, and resurface the head us-ing a figure-eight sanding pattern.

Rotate the cylinder head several times for aneven resurfacement.

4-8

CYLINDER HEAD ENG

New

New

22 Nm (2.2 mkg)M8 (1 4)

20 Nm (2.2 mkg)M8 (5 6

NOTE:

***************************************

NOTE:

CAUTION:

***************************************

SR********

CYLINDER HEAD INSTALLATION1. Install:Dowel pins 1 Gasket 2Gasket (cylinder head) 3

2. Install:Cylinder head

apply engine oil onto the nut threads.Tighten the bolts starting with the lowest numbered one.

3. Install:Calm sprocketTiming chain

Installing steps:Turn the crank shaft counterclockwise until theslit 1 matches the stationary pointer 2 .

Align the dowel pin 3 on the camshaft with thestationary pointer 4 on the cylinder head.

Align the “I” mark 5 on the cam sprocket withthe stationary pointer 6 on the cylinder head.

Fit the timing chain 7 onto cam sprocket 8and install the cam sprocket on the camshaft.

When installing the cam sprocket, keep the tim-ing chain as tight as possible on the exhaustside.

Do not turn the crankshaft during installa-tion of the camshaft. Damage or impropervalve timing will result.

Remove the safety wire from the timing chain.

4-9

CYLINDER HEAD ENG

60 Nm (6.0 mkg)

NOTE:

4. Install:Plate washerBolt (timing chain)Timing chain tensioner assembly

5. Tighten:Bolt (timing chain)

Install the bolt while holding the magnetomounting bolt with a wrench.

6. Check:Magneto rotor slitAlign the stationary pointer with the crank-case cover (left).

Cam sprocket “I” markAlign the stationary pointer with the cylinderhead.Out of alignment Adjust.

7. Check:Timing chain tensionRefer to “TIMING CHAIN ADJUSTMENT”section in CHAPTER 3.

Valve clearanceRefer to “VALVE CLEARANCE ADJUST-MENT” section in CHAPTER 3.

4-10

CAM SHAFT AND ROCKER ARMS ENG


123456789

Cam shaft and rocker arm removalCylinder headLock washerPlateCollarCam shaftRocker arm shaft (intake side)Rocker arm shaft (exhaust side)Rocker armO-ringNut/Adjuster

11111121

2/2

Remove the parts in order.Refer to the “CYLINDER HEAD” section.

Refer to the “ROCKER ARM AND ROCKER ARM SHAFT REMOVAL/CAMSHAFT AND ROCKER ARM INSTALLATION” section.

Refer to the “CAMSHAFT AND ROCKERARM INSTALLATION” section.


14 Nm (1.4 mkg)

14 Nm (1.4 mkg)

8 Nm (0.8 mkg)

CAM SHAFT AND ROCKER ARMS

4-11


NOTE:

NOTE:

SR******

ROCKER ARM AND ROCKER ARM SHAFTREMOVAL1. Remove:Camshaft 1Collar (camshaft) 2

Use 10 mm bolt 3 to remove the camshaft.

2. Remove:Rocker arm shaft (intake)Rocker arm shaft (exhaust)

Attach a rocker arm shaft puller bolt 1 andweight 2 to the rocker arm shaft and slide outthe shaft.

Rocker arm shaft puller bolt:90890-01083

Weight:90890-01084

YP402052

CAMSHAFT INSPECTION1. Inspect:Cam lobesPitting/Scratches/Blue discoloration Replace.

2. Measure:Cam lobes length A and B .Out of specification Replace.

Cam lobes length:Intake:

A 36.537 36.637 mm<Limit: 36.45 mm>B 30.13 30.231 mm<Limit: 30.05 mm>

Exhaust:A 36.577 36.677 mm<Limit: 36.49 mm>B 30.214 30.314 mm<Limit: 30.13 mm>

3. Inspect:Camshaft oil passageStuffed Blow out oil passage with com-pressed the air.

4-12


***************************************

***************************************

YP402060

ROCKER ARMS AND ROCKER ARMSHAFTS INSPECTION1. Inspect:Rocker arm shaftsRocker armsWear/Pitting/Scratches/Blue discoloration Replace.

Inspection steps: Inspect the two contact areas on the rockerarms for signs of unusual wear.

Rocker arm shaft hole.Cam-lobe contact surface.Excessive wear Replace.

Inspect the surface condition of the rocker armshafts.Pitting/scratches/blue discoloration Re-place or check lubrication.

Measure the inside diameter a of the rockerarm holes.Out of specification Replace.

Inside diameter (rocker arm):12.000 12.018 mm<Limit: 12.036 mm>

Measure the outside diameter of the rockerarm shafts.Out of specification Replace.

Outside diameter (rocker arm shaft):

11.985 11.991 mm<Limit: 11.950 mm>

SR******

CAMSHAFT AND ROCKER ARMINSTALLATION1. Lubricate:Camshaft

Camshaft:Molybdenum disulfide oil

Camshaft bearing:Engine oil

4-13

ENGCAM SHAFT AND ROCKER ARMS

NOTE:

CAUTION:

NOTE:

New8 Nm (0.8 mkg)

NOTE:

2. Apply:Molybdenum disulfide oil(onto the rocker arm and rocker arm shaft)

Molybdenum disulfide oil

3. Install:Rocker armRocker arm shaft 1

Apply engine oil onto the outside of the rockerarm shaft and apply molybdenum disulfide oilonto the inside of the rocker arm.

Install the rocker arm shaft (intake), mach thecut away a and bolt hole b .

Make sure that the rocker shaft installdirection.

Install the rocker arm shaft into the threadside for the out.

4. Install:Camshaft 1Collar 2

Apply engine oil onto the cam profile face andjournal face.

Install the camshaft, mach the dowel pin aand cylinder head mark b .

5. Install:Plate 1Lock washer 2 Bolt 3

After tighten the bolt, bend the end of the rockwasher.

4-14


1

2345678

Valves and valve springs removalCylinder headRocker arm, Camshaft

Valve cotters

Spring retainerValve spring (inner)Valve spring (outer)Valve (intake)Valve (exhaust)Valve guide (stem seal)Spring seat

4

2221122

Remove the parts in order.Refer to “CYLINDER HEAD” section.Refer to “CAMSHAFT AND ROCKERARMS” section.

Refer to “VALVES AND VALVESPRINGS REMOVAL/INSTALLATION”section.

Refer to “VALVES AND VALVE SPRINGS INSTALLATION” section.


VALVES AND VALVE SPRINGS ENG

VALVES AND VALVE SPRINGS

4-15


NOTE:

CAUTION:

ab

***************************************

NOTE:

YP401150

VALVES AND VALVE SPRINGS REMOVAL1. Remove:Valve cotters 1

Attach a valve spring compressor and attach-ment 2 between the valve spring retainer andcylinder head to remove the valve cotters.

Do not compress so much as to avoid dam-age to the valve spring.

Valve spring compressor:90890-01253

Valve spring compressor attachment:

90890-04108

NB402010

VALVES AND VALVE GUIDES1. Measure:Stem-to-guide clearance

Stem-to-guide clearance =valve guide inside diameter –valve stem diameter

Out of specification Replace the valveguide.

Clearance (stem to guide):Intake:

0.010 0.037 mm<Limit: 0.08 mm>Exhaust:

0.025 0.052 mm<Limit: 0.10 mm>

2. Replace:Valve guide

Replacement steps:

Heat the cylinder head in an oven to 100C toease guide removal and installation and tomaintain correct fit.

Remove the valve guide using a valve guideremover 1 .

4-16


NOTE:

***************************************

NOTE:

Install the new valve guide using a valve guideinstaller 2 and valve guide remover 1 .

After installing the valve guide, bore the valveguide using a valve guide reamer 3 to obtainproper stem-to-guide clearance.

Valve guide remover (6 mm):90890-04064

Valve guide installer (6 mm):90890-04065

Valve guide reamer (6 mm):90890-04066

Reface the valve seat after replacing the valveguide.

3. Eliminate:Carbon deposits (from the valve face)

4. Inspect:Valvel facePitting/wear Grind the face.

Valve stem endMushroom shape or diameter larger than thebody of the stem Replace.

5. Measure:Margin thickness aOut of specification Replace.

Margin thickness:Intake 0.8 1.2 mmExhaust 0.8 1.2 mm

6. Measure:Runout (valve stem)Out of specification Replace.

Runout:Less than 0.03 mm

Always replace the guide when installing anew valve.

Always replace the oil seal if the valve is re-moved or replaced.

4-17


***************************************

***************************************

***************************************

NOTE:

CAUTION:

EB402020

VALVE SEATS INSPECTION1. Eliminate:Carbon deposits(from the valve face and valve seat)

2. Inspect:Valve seatsPitting/wear Reface the valve seat.

3. Measure:Valve seat width aOut of specification Reface the valve seat.

Valve seat width:Intake:

0.9 1.1 mm<Limit: 1.6 mm>

Exhaust:0.9 1.1 mm<Limit: 1.6 mm>

Measurement steps:Apply Mechanic’s blueing dye (Dykem) 1 tothe valve face.

Install the valve into the cylinder head.Press the valve through the valve guide andonto the valve seat to make a clear pattern.

Measure the valve seat width. Where the valveseat and valve face made contact, blueing willhave been removed.

If the valve seat is too wide, too narrow, or theseat is not centered, the valve seat must be re-placed.

EB402020

4. Lap:Valve faceValve seat

After replacing the valve seat, valve and valveguide, the valve seat and valve face should belapped.

Lapping steps:Apply a coarse lapping compound a to thevalve face.

Do not let compound enter the gap betweenthe valve stem and the guide.

4-18


NOTE:

NOTE:

***************************************

Apply molybdenum disulfide oil to the valvestem.

Install the valve into the cylinder head.

Turn the valve until the valve face and valveseat are evenly polished, then clean off allcompound.

Valve lapper:90890-04101

For best lapping results, lightly tap the valveseat while rotating the valve back and forth be-tween your hand.

Apply a fine lapping compound to the valveface and repeat the above steps.

Make sure to clean off all compound from thevalve face and valve seat after every lappingoperation.

Apply Mechanic’s blueing dye (Dykem) b tothe valve face.

Install the valve into the cylinder head.Press the valve through the valve guide andonto the valve seat to make a clear pattern.

Measure the valve seat width c again.

EB404032

VALVES AND VALVE SPRINGSINSTALLATION1. Deburr:Valve stem endUse an oil stone to smooth the stem end.

4-19


Molybdenum disulfide oil

New

NOTE:

NOTE:

CAUTION:

2. Apply:Molybdenum disulfide oil(onto the valve stem 3 and oil seal 2 )

3. Install:Valve spring seat 1Valve stem seat 2 Valve 3(into the cylinder head)

Valve spring 4Spring retainer 5

Install the valve spring with the larger pitch afacing upwards.

b Smaller pitch

4. Install:Valve cotters 1

Install the valve cotters while compressing thevalve spring with a valve spring compressor andattachment 2 .

Valve spring compressor:90890-01253

Valve spring compressorattachment:

90890-04108

5. Secure the valve cotters onto the valve stemby tapping lightly with a piece of wood.

Do not hit so much as to damage the valve.

4-20

CYLINDER AND PISTON ENG


123456789

Cylinder and piston removalCylinder headTiming chain guide (exhaust side)Cylinder/O-ringO-ringDowel pinCylinder gasketPiston pin circlipPiston pinPistonPiston ring set

11/11212111

Remove the parts in order.Refer to “CYLINDER HEAD” section.

Refer to “PISTON AND PISTON RINGSREMOVAL” section.Refer to “PISTON RINGS, PISTON ANDCYLINDER INSTALLATION” section.

Refer to “PISTON RINGS, PISTON ANDCYLINDER INSTALLATION” section.


CYLINDER AND PISTON

4-21


NOTE:

NOTE:

***************************************

NOTE:

YP******

PISTON AND PISTON RINGS REMOVAL1. Remove:Piston pin circlip 1Piston pin 2Piston 3

Before removing the piston pin circlip, cover thecrankcase opening with a clean towel or rag toprevent the circlip from falling into the crankcase cavity.

2. Remove:Top ring2nd ringOil ring

When removing the piston ring, open the endgap of the ring by fingers, and push up the otherside of the ring.

EB402100

CYLINDER AND PISTON INSPECTION1. Inspect:Cylinder and piston wallsVertical scratches Rebore or replace thecylinder and the piston.

2. Measure:Piston-to-cylinder clearance

Measurement steps:1st step:Measure the cylinder bore “C” with a cylinderbore gauge.

Measure the cylinder bore “C” in parallel to andat right angles to the crankshaft. Then, find theaverage of the measurements.

4-22


***************************************

Cylinder bore “C” 57.00 57.02 mm

Taper limit “T” 0.05mm

Out of round “R” 0.01mm

“C” = Maximum D

“T” = (Maximum D 1 or D2) – (Maximum D 5 or D6)

“R” = (Maximum D 1, D3 or D5)– (Minimum D 2, D4 or D6)

If out of specification, rebore or replace the cyl-inder, and replace the piston and piston ringsas a set.

2nd step:Measure the piston skirt diameter “P” with amicrometer.

a 5.5 mm from from the piston bottom edge.

Piston size P

Standard 56.960 56.975 mm

Oversize 1 0.25 mm

Oversize 2 0.50 mm

If out of specification, replace the piston andthe piston rings as a set.

3rd step:Calculate the piston-to-cylinder clearance us-ing the following formula:

Piston-to-cylinder clearance =Cylinder bore “C” –Piston skirt diameter “P”

Piston-to-cylinder clearance:0.025 0.045 mm

If out of specification, rebore or replace the cyl-inder, and replace the piston and piston ringsas a set.

4-23


NOTE:

NOTE:

NOTE:

EB402110

PISTON RING INSPECTION1. Measure:Side clearanceOut of specification Replace the pistonand the piston rings as a set.

Eliminate the carbon deposits from the pistonring grooves and rings before measuring theside clearance.

Side clearance:Top ring: <Limit>

0.03 0.07 mm <0.15 mm>2nd ring: <Limit>

0.02 0.06 mm <0.15 mm>

2. Position:Piston ring(into the cylinder)

Push the ring with the piston crown so that thering will be at a right angle to the cylinder bore.

a 5 mm

3. Measure:End gapOut of specification Replace.

You cannot measure the end gap on the expan-der spacer of the oil ring. If the oil ring rails showexcessive gap, replace all three rings.

End gap:Top ring: <Limit>

0.15 0.35 mm <0.60 mm>2nd ring: <Limit>

0.15 0.35 mm <0.60 mm>Oil ring: 0.3 0.9 mm

4-24


***************************************

ba

***************************************

NOTE:

EB402120

PISTON PIN INSPECTION1. Inspect:Piston pinBlue discoloration/grooves Replace, theninspect the lubrication system.

2. Measure:Piston pin-to-piston clearance

Measurement steps:Measure the piston pin outside diameter a .If out of specification, replace the piston pin.

Outside diameter (piston pin):14.978 14.992 mm<Limit> 14.975 mm

Measure the piston inside diameter b .Calculate the piston pin-to-piston clearanceusing the following formula:

Piston pin-to-piston clearance =Bore size (piston pin) –Outside diameter (piston pin)

If out of specification, replace the piston.

Clearance (piston pin-to-piston):0.010 0.035 mm

EB404184

PISTON RINGS, PISTON AND CYLINDERINSTALLATION1. Install:Top ring 12nd ring 2Side rails (oil ring) 3Expander spacer (oil ring) 4

Make sure to install the piston rings so that themanufacturer’s marks or numbers are locatedon the upper side of the rings.

Lubricate the pistons and piston rings liberallywith engine oil.

4-25


New

NOTE:

New

NOTE:

Engine oil

New

NOTE:

2. Install:Piston 1Piston pin 2Piston pin clip 3

Apply engine oil onto the piston pins.The “” mark a on the piston must face theexhaust side of the cylinder.

Before installing the piston pin clip, cover thecrankcase opening with a clean rag to preventthe piston pin clip from falling into the crank-case.

Make sure to install each piston in its respec-tive cylinder.

3. Install:Gasket (cylinder) Dowel pins

4. Position:Piston rings

Offset the piston ring end gaps as shown.

a Top ring endb Oil ring end (lower)c Oil ring end (upper)d 2nd ring end

5. Lubricate:Piston outer surfacePiston ringCylinder inner surface

6. Install:Gasket (cylinder) 1 Cylinder 2

Install the cylinder with one hand while com-pressing the piston rings with the other hand.

Pass the timing chain and timing chain guide(exhaust side) through the timing chain cavity.

4-26

CLUTCH ENG


123456

Crankcase cover (right) removalDrain the engine oil

NutFoot rest (right)Clutch cableCrankcase cover (right)Crankcase cover gasket (right)Dowel pins

111112

Remove the parts in order.Refer to “ENGINE OIL REPLACEMENT”section in CHAPTER 3.


45 Nm (4.5 mkg)

7 Nm (0.7 mkg)

CLUTCHCRANKCASE COVER (RIGHT)

4-27

CLUTCH ENG


123456789

1011

4143

1/111111

1/1

Remove the parts in order.Refer to “ENGINE REMOVAL” section.

Refer to “CLUTCH INSTALLATION” section.

Clutch removalSprocket coverClutch springsPressure plateFriction platesClutch platesNut/Lock washerClutch bossPlate washerPrimary driven gearBallPush rod #2Push lever screw/Gasket

Refer to “CLUTCH INSTALLATION” section.

Refer to “CLUTCH REMOVAL/INSTALLATION” section.

8 Nm (0.8 mkg)70 Nm (7.0 mkg)

12 Nm (1.2 mkg)

6 Nm (0.6 mkg)

CLUTCH

4-28

CLUTCH ENG


12131415161718

Push lever axleTorsion springCirclipOil sealNut/WasherPush rod #1/O-ringPush plate

1111

1/11/11

Refer to “CLUTCH INSTALLATION” sec-tion.

Refer to “CLUTCH INSTALLATION” sec-tion.


8 Nm (0.8 mkg)70 Nm (7.0 mkg)

12 Nm (1.2 mkg)

6 Nm (0.6 mkg)

4-29

CLUTCH ENG

NOTE:

SR401061

CLUTCH REMOVAL1. Remove:Nut 1 (clutch boss)Lock washer 2Clutch boss 3Straighten the lock washer tab 2 .

Loosen the clutch boss nut 1 while holding theclutch boss with a clutch holding tool 4 .

Clutch holding tool:90890-04086

SR402181

CLUTCH INSPECTION1. Inspect:Friction platesDamage/wear Replace the friction platesas a set.

2. Measure:Friction plate thicknessOut of specification Replace the frictionplates as a set.Measure at four places.

Thickness (friction plate):2.9 3.1 mm<Limit: 2.7 mm>

3. Inspect:Clutch platesDamage Replace the clutch plates as aset.

4. Measure:Clutch plate warpageOut of specification Replace the clutchplates as a set.Use a surface plate and a feeler gauge 1 .

Warp limit (clutch plate):Less tan 0.05 mm

5. Inspect:Clutch springsDamage Replace the clutch springs as aset.

4-30

CLUTCH ENG

NOTE:

New12 Nm (1.2 mkg)

NOTE:

6. Measure:Free length (clutch spring) aOut of specification Replace the clutchsprings as a set.

Free length (clutch spring):34.5 mm<Lilmit: 32.9 mm>

7. Inspect:Dogs on the primary driven gear 1Scoring/wear/damage Deburr or re-place.

Clutch boss splines 2Scoring/wear/damage Replace clutchboss.

Scoring on the clutch housing dogs and theclutch boss splines will cause erratic operation.

SR********

PUSH ROD INSPECTION1. Inspect:Push rod #1 1Ball 2Push rod #2 3Wear/crack/damage Replace.

SR******

CLUTCH INSTALLATION1. Install:Push lever axle 1Gasket 2 Screw 3

2. Install:Primary driven gear 1Plate washer 2Clutch boss 3

Tighten the nut (primary drive gear) while hold-ing the rotor with the sheave holder 3 .

4-31

CLUTCH ENG

New70 Nm (7.0 mkg)

NOTE:

NOTE:

New

6 Nm (0.6 mkg)

NOTE:

3. Install:Lock washer 1 Nut 2 (clutch boss)

Install the clutch boss nut 2 while holding theclutch boss with a clutch holding tool 3 .

Clutch holding tool:90890-04086

4. Bend:Lock washer tab(along a flat side of the end)

5. Install:Friction plate 1Clutch plate 2

Install the clutch plates and friction plates al-ternately on the clutch boss, starting with a fric-tion plate and ending with a friction plate.

Coat all clutch and friction plates with engineoil before installation.

6. Install:Push rod #2Ball

7. Install:Push rod #1 1O-ring 2 Push plate 3Plate washer 4Nut 5 (push rod #1)

8. Install:Pressure plate 1Compression springs 2Bolts 3 (clutch springs)

Tighten the clutch spring bolts in stage, using acrisscross pattern.

4-32

CLUTCH ENG

***************************************

CAUTION:

***************************************8 Nm (0.8 mkg)

9. Check:Push lever positionPush the push lever assembly in the arrowdirection and make sure that match marksare be aligned Adjust.

a Match mark on the push lever assemblyb Match mark on the crankcase

10. Adjust:Push lever position

Adjustment steps:Loosen the locknut 1 .Turn the adjuster 2 clockwise or counter-clockwise to match alignment marks.

Hold the adjuster to prevent it from moving andtighten the locknut to specification.

Take care not to overtighten the adjuster 2and to remove the free play between bothpush rods.

Tighten the lock nut 1 .

4-33

OIL PUMP ENG


12345

6

Oil pump removalClutch

NutLock washerPrimary drive gearOil pump coverOil pump assembly

Gasket (oil pump cover)

11111

1

Remove the parts in order.Refer to “CLUTCH” section.

Refer to “PRIMARY DRIVE GEAR REMOVAL/INSTALLATION” section.

Refer to “OIL PUMP REMOVAL/INSTAL-LATION” section


7 Nm (0.7 mkg)

50 Nm (5.0 mkg)

OIL PUMP

4-34

OIL PUMP ENG


Oil pump disassemblyOil pump housingDowel pinOil pump driven gearDowel pinsInner rotorOuter rotorHousing

1112111

Disassemble the parts in order.

Reverse the disassembly procedure forassembly.

7 Nm (0.7 mkg)

11111111111111112111111111111111

34567

4-35

OIL PUMP ENG

NOTE:

NOTE:

SR401070

PRIMARY DRIVE GEAR REMOVAL

Straighten the lock washer tab.

1. Remove:Nut (primary drive gear) 1Lock washer 2Primary drive gear 3

Place a folded aluminium plate or copper wash-er a between the teeth of the balancer drivegear 4 and balancer driven gear 5 .

T402140

OIL PUMP INSPECTION1. Measure:Tip clearance A(between the inner rotor 1 and the outer ro-tor 2 )

Side clearance B(between the outer rotor 2 and the pumphousing 3 )Out of specification Replace the oil pumpassembly.

Housing and rotor clearance C(between the pump housing 3 and the ro-tors 1 , 2 .)Out of specification Replace the oil pumpassembly.

Tip clearance A :0.03 0.09 mm <Limit: 0.14 mm>

Side clearance B :0.10 0.15 mm <Limit: 0.35 mm>

Housing and rotor clearance C :0.03 0.09 mm <Limit: 0.14 mm>

SR******

OIL DELIVERY PASSAGE INSPECTION (CR-ANK CASE COVER (right))1. Check:Oil delivery passageBlockage Blow by the compressed air.

4-36

OIL PUMP ENG

New

50 Nm (5.0 mkg)

NOTE:

SR404010

OIL PUMP INSTALLATION1. Lubricate:Oil delivery passage (crankcase right)Oil pump assembly

Recommended lubricant:Engine oil

SR404140

PRIMARY DRIVE GEAR INSTALLATION1. Install:Primary drive gear 1Lock washer 2 Nut (primary drive gear) 3

Place a folded aluminium plate or copperwasher a between the teeth of the balancerdrive gear 4 and balancer driven gear 5 .

Bend the lock washer tab, after tighten the nutflats.

4-37

BALANCER GEAR ENG


12

3456789

10

Balancer gear removalClutchPrimary drive gearNut/Lock washerBalancer driven gear

Woodruff keyClaw washerBalancer drive gearBuffer bossCompression springDowel pinsWoodruff keyPlate washer

1/11

11116311

Remove the parts in order.Refer to “CLUTCH” section.Refer to “OIL PUMP” section.Refer to “BALANCER DRIVEN GEAR REMOVAL/BALANCER GEAR INSTALLATION” section.


Refer to “BALANCER DRIVE GEAR ASSEMBLY” section.

50 Nm (5.0 mkg)

BALANCER GEAR

4-38

BALANCER GEAR ENG

NOTE:

NOTE:

NOTE:

NOTE:

SR******

BALANCER DRIVEN GEAR REMOVAL

Straighten the lock washer tab.

1. Remove:Nut (balancer driven gear) 1Lock washer 2Balancer driven gear 3

Place a folded aluminium plate or copper wash-er a between the teeth of the balancer drivegear 4 and balancer driven gear 3 .

SR******

DRIVE GEAR INSPECTION1. Inspect:Balancer drive gear 1Buffer boss 2Compression spring 3Dowel pins 4Wear/Pitting/Scratches Replace.

SR******

BALANCER DRIVE GEAR ASSEMBLY1. Assembly:Dowel pins 1Compression springs 2

Install the dowel pins and compression springsalternately as shown as.

2. Install:Buffer boss 1

Align the punched mark a on the buffer bosswith the one on the balancer drive gear.

4-39

BALANCER GEAR ENG

NOTE:

New

50 Nm (5.0 mkg)

NOTE:

SR******

BALANCER GEAR INSTALLATION1. Install:Balancer driven gear 1

Install the balancer driven gear, then mesh thebalancer driven gear match mark a and ba-lancer drive gear assembly match mark b .

2. Install:Lock washer 1 Nut (balancer drive gear) 2

Place a folded aluminium plate or copperwasher a between the teeth of the balancerdrive gear 3 and balancer driven gear 4 .

Bend the lock washer tab, after tighten the nutflats.

4-40

SHIFT SHAFT AND SEGMENT ENG


123456789

Shift shaft and segment removalClutchShift pedalShift shaftPlate washerTorsion springStopper leverPlate washerCirclipTorsion springCollarTension spring

111111111

Remove the parts in order.Refer to “CLUTCH” section.Refer to “ENGINE REMOVAL” section.

Refer to “SHIFT SHAFT REMOVAL/INSTALLATION” section.

12 Nm (1.2 mkg)

SHIFT SHAFT AND SEGMENT

4-41



10111213

ScrewSegmentDowel pins (short length)Dowel pins (long length)

1141


Refer to “SEGMENT INSTALLATION” section.

12 Nm (1.2 mkg)

4-42


NOTE:

NOTE:

SR******

SHIFT SHAFT REMOVAL1. Remove:Shift shaft assembly 1

Push the shift lever arm 2 and the stopper lever3 to the arrow direction and remove them fromthe segment.

T402200

SHIFT SHAFT INSPECTION1. Inspect:Stopper leverRoller turns roughly Replace.Bends/damage Replace.

2. Inspect:Torsion springs (stopper lever and shift arm)Wear/damage Replace.

3. Inspect:Shift shaft assembly 1Shift lever 2Bends/wear/damage Replace.

SR******

SEGMENT INSTALLATION1. Install:Segment 1Dowel pins 2 (short length)Dowel pin 3 (long length)

Install the dowel pin 2 (long length) into thehole beside the match mark a position.

4-43


NOTE:

12 Nm (1.2 mkg)

***************************************

***************************************

2. Install:Segment 1

Fit the dowel pin 2 (long length) on the seg-ment to the locating hole a on the sift cam andinstall the segment.

3. Tighten:Screw 1

SR******

SIFT SHAFT INSTALLATION1. Install:Shift shaft assembly

Instaling steps:Set the stopper lever and return spring to theshift shaft.

Mesh the stopper lever 1 with the shift camsegment.

Install the shift lever 2 to the shift cam seg-ment.

After installing the shift shaft, check the shiftcam for smooth operation by turning the shiftshaft with your hand.

2. Check:Shift lever 1 positionGaps a and b are not equal Replace thedefective parts.

4-44

CDI MAGNETO AND STARTER CLUTCH ENG


1234

Crankcase cover (left) removalDrain the engine oil

Side cover

Drive sprocket coverDCI magneto lead couplersNeutral switch lead connectorCrankcase cover (left)GasketDowel pins

1112

Remove the parts in order.Refer to “ENGINE OIL REPLACEMENT”section in CHAPTER 3.Refer to “SIDE COVER, SEAT ANDFUEL TANK” section in CHAPTER 3.

Refer to “ENGINE REMOVAL” section.


7 Nm (0.7 mkg)

CDI MAGNETO AND STARTER CLUTCHCRANKCASE COVER (LEFT)

4-45



1234

Pickup coil and stator coil removalClamp (stator coil)Clamp (pickup coil)Pickup coilStator coil

1111



3 Nm (0.3 mkg)

7 Nm (0.7 mkg)

PICKUP COIL AND STATOR COIL

4-46



1

23456789

1011

CDI magneto and starter clutch removalCDI magneto

Idle shaft /collarStarter idle gearWoodruff keyStarter wheel gearShimDowel pins (Inner)Spring capsCompression springsDowel pins (outer)Starter clutch

1

1111133331


Refer to “CDI MAGNETO REMOVAL/INSTALLATION” section.

Refer to “CDI MAGNETO INSTALLATION” section.

Refer to “STARTER CLUTCH INSTALLATION” seciton.

Remove the removal procedure torinstallation.

30 Nm (3.0 mkg)

50 Nm (5.0 mkg)

CDI MAGNETO AND STARTER CLUTCH

4-47


NOTE:

NOTE:

***************************************

***************************************

YP401081

C.D.I. MAGNETO REMOVAL1. Remove:Bolt 1 (magneto)Plain washer 2

Loosen the bolt (magneto) 1 while holdingthe rotor with a sheave holder 3 .

Do not allow the sheave holder to touch theprojection on the magneto.

Sheave holder:90890-01701

2. Remove:CDI magneto assembly 1Woodruff key

Remove the magneto using sheave holder 2 ,rotor puller 3 and rotor puller attachment 4 .

Rotor puller:90890-01080

Rotor puller attachment:90890-04052

SR402163

STARTER CLUTCH INSPECTION1. Check:Starter clutch operationPush the dowel pins to the arrow direction.Unsmooth operation Replace.

Checking steps:Hold the starter clutch.When turning the starter wheel gear clockwise

a , the starter clutch and the starter wheelgear should be engaged.

If not, the starter clutch is faulty. Replace it.When turning the starter wheel gear counter-clockwise b , it should turn freely.

If not, the starter clutch is faulty. Replace it.

2. Inspect:Dowel pins 1Compression springs 2Spring caps 3Wear/Damage Replace.

4-48


30 Nm (3.0 mkg)

NOTE:

3. Inspect:Starter wheel gear(contacting surface)Pitting/Wear/Damage Replace.

SR******

STARTER CLUTCH INSTALLATION1. Install:Starter clutch assembly 1

2. Unloosen the starter clutch assembly by us-ing the center punch.

3. Install:Compression springs 1Spring caps 2Dowel pins 3

YP404131

C.D.I. MAGNETO INSTALLATION1. Install:Shim 1Starter wheel gear 2Woodruff key 3

2. Install:C.D.I. magneto assembly 1

Clean the tapered portion of the crankshaftand the magneto hub.

When installing the magneto rotor, make surethe woodruff key is properly seated in the keyway of the crankshaft and turning the staterwheel gear 2 clockwise.

4-49


50 Nm (5.0 mkg)

NOTE:

3. Tighten:CDI magneto assembly 1

Tighten the bolt while holding the CDI magnetoassembly with the sheave holder 2 .

Sheave holder:90890-01701

4-50

CRANKCASE AND CRANK SHAFT ENG


1

Crankcase separationEngineCylinder headCylinder and piston

ClutchPrimary drive gear/oil pumpBalancer weight drive gear

Shift shaft and segment

CDI magneto/starter clutch

Timing chain guide (intake) 1

Remove the parts in order.Refer to “ENGINE REMOVAL” section.Refer to “CYLINDER HEAD” section.Refer to “CYLINDER AND PISTON”section.

Refer to “CLUTCH” section.Refer to “OIL PUMP” section.Refer to “BALANCER DRIVE GEAR”section.Refer to “SHIFT SHAFT AND SEGMENT” section.Refer to “CDI MAGNETO AND STARTER CLUTCH” section.

8 Nm (0.8 mkg)

7 Nm (0.7 mkg)

CRANK CASE AND CRANKSHAFTCRANKCASE

4-51



23

4

Timing chainCrankcase

Dowel pins

11

2

Refer to “CRANKCASE SEPARATION/INSTALLATION” section.


8 Nm (0.8 mkg)

7 Nm (0.7 mkg)

4-52



1234567

Crankshaft and balancer weight removalBalancer weightCrankshaft assemblyDowel pinPlunger sealCompression springBearing (balancer weight)Bearing (crankshaft right)

1111111


Refer to “BALANCER WEIGHT INSTALLATION” seciton.

Refer to “PLUNGER SEAL REMOVAL/INSTALLATION” section.


CRANKSHAFT AND BALANCER WEIGHT

4-53


NOTE:

NOTE:

CAUTION:

NOTE:

SR401132

CRANKCASE SEPARATION1. Remove:Crankcase screws

The numbers embossed on the crankcase in-dicate the tightening sequence. Loosen thescrews in decreasing numerical order (seenumbers on the illustration).

Loosen each screw 1/4 turn at a time and re-move them after all are loose.

2. Remove:Right crankcase half

Set the left crankcase half under then put in theflat head screw driver to the separating slit a .

Do not use the flat head screw driver ex-cept place as shown.

The left crankcase half should be under.Separate the crankcase after first checkingthat the shift cam segments and the driveaxle circlip can be removed.

Do not damage the crankcase mating sur-faces.

SR******

PLUNGER SEAL REMOVAL1. Remove:Dowel pin 1Plunger seal 2Compression spring 3

Remove the plunger seal and compressionspring, push the plunger seal lightly and removethe dowel pin.

4-54


NOTE:

T******

CRANKSHAFT INSPECTION1. Measure:Crankshaft runoutOut of specification Replace crankshaftand/or bearing.

Measure the crankshaft runout with the crank-shaft assembly turning slowly.

Runout limit:0.03 mm

2. Measure:Big end side clearanceOut of specification Replace big end bear-ing, crank pin and/or connecting rod.

Big end side clearance:0.35 0.65 mm

Limit0.1 mm

3. Measure:Crank widthOut of specification Replace crankshaft.

Crank width:55.95 56.00 mm

4. Inspect:Timing chain sprocket 1Wear/Damage Replace crankshaft.

Bearing 2Wear/Crack/Damage Replace crank-shaft.

5. Inspect:Crankshaft journalClogged Blow out the journal with com-pressed air.

4-55


CAUTION:

NOTE:

7 Nm (0.7 mkg)

NOTE:

SR******

PLUNGER SEAL INSTALLATION1. Install:Compression spring 1Plunger seal 2Dowel pin 3

2. Check the plunger seal smooth operationpushing the plunger seal by your finger.

T*****

BALANCER WEIGHT INSTALLATION1. Install:Crankshaft assembly 1Balancer weight assembly 2

Do not use the hammer forcefully duringinstallation of the crankshaft. Damage thecrankcase oil seal lip and gear teeth.

SR404073

CRANKCASE INSTALLATION1. Clean all the gasket mating surface and

crankcase mating surface thoroughly.2. Apply:Sealant(onto the crankcase mating surfaces)

Yamaha bond No.1215:90890-85505

DO NOT ALLOW any sealant to come in con-tact with the oil gallery a .

3. Tighten:Crankcase right half

Tighten the screws in decreasing numerical or-der (see numbers on the illustration).

4-56

TRANSMISSION SIFT CAM AND SHIFT FORK ENG


123456789

10

Transmission, shift cam and shift fork removalCrankcase separating

Shift fork guide bar 2 (short length)Shift fork guide bar 1 (long length)Shift camShift fork 1 “C” (center)Shift fork 2 “R” (right)Shift fork 3 “L” (left)Main axle assemblyPlate washerDrive axle assemblyPlate washer

1111111111


Refer to “CRANKCASE AND CRANKSHAFT” section.

Refer to “TRANSMISSION, SHIFT CAMAND SHIFT FORK INSTALLATION” section.


Refer to “TRANSMISSION, SHIFT CAMAND SHIFT FORK REMOVAL/INSTALLATION” section.

TRANSMISSION, SHIFT CAM AND SHIFT FORK

4-57



Drive axle and main axle disassemblySecond wheel gearFirst wheel gearFifth wheel gearCirclip/washerThird wheel gearForth wheel gearDrive axleSecond pinion gearForth pinion gearThird pinion gearCirclip/washerFifth pinion gear gearMain axle

111

1/1111111

1/111



8

1234567

910111213

DRIVE AXLE AND MAIN AXLE

4-58


WARNING

SR******

TRANSMISSION, SHIFT CAM AND SHIFTFORK REMOVAL1. Install:O-Ring 1To the drive sprocket groove.

2. Remove:Drive axle assembly 1Main axle assembly 2Remove them at same the time.

T402190

SHIFT FORK SHIFT CAM INSPECTION1. Inspect:Shift fork cam follower 1Shift fork pawl 2Scoring/bends/wear/damage Replace.

2. Inspect:Shift cam groovesWear/damage/scratches Replace.

Shift cam segmentDamage/wear Replace.

3. Inspect:Shift fork 1 “C” (center) 1Shift fork 2 “R” (right) 2Shift fork 3 “L” (left) 3Guide bar 4Shift cam 5Dowel pin 6Roll the guide bar on a flat surface.Bends Replace.

Do not attempt to straighten a bent guidebar.

4-59


NOTE:

NOTE:

NOTE:

4. Check:Shift fork movement(on the guide bar)Unsmooth operation Replace the shiftfork and the guide bar.

When damaged the shift fork and mission gear,replace the facing each gear as set.

SR******

TRANSMISSION, SHIFT CAM AND SHIFTFORK INSTALLATION1. Measure:Main axle assembled length a

Assembled length (main axle):90.9 91.1 mm

2. Install:O-ring 1To the drive sprocket folder groove.

3. Install:Shift fork 3 “L” (left) 1(face the “L” side for the clutch side.)

Shift fork 2 “R” (right) 2(face the “R” side for the clutch side.)

Shift fork 1 “C” (center) 3(face the “C” side for the magneto side.)

Shift fork guide bar 1 4 (long)Shift fork guide bar 2 5 (short)

Install the shift forks with the embossed mark tothe right and in sequence (R, C, L) beginningfrom the right.

4. Check:Shift cam operationUnsmooth operation Repair.

Check the transmission and shift forks forsmooth operation by turning the shift cam withyour hand.

ENG

CHAPTER 5.CARBURETION

CARBURETOR 5-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CARBURETOR ASSEMBLY 5-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FUEL LEVEL ADJUSTMENT 5-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5-1

CARBURETOR CARB


1234

Carburetor removalSide coverSeatFuel tankHeater unit lead

Carburetor joint clamp screwAir filter joint clamp screwCarburetor assemblyCarburetor top

1111


NOTE:

Refer to “SIDE COVER, SEAT AND FUEL TANK” section in CHAPTER 3.

Disconnect the cable from wireharness.

Loosen.


NOTE:

EB600000

CARBURETIONCARBURETOR

5-2

CARBURETOR CARB


Carburetor disassemblyThrottle cableThrottle valve assemblyThrottle valve springMixing chamber top/O-ringDrain screw assemblyFloat chamberGasket (float chamber)Float pin/floatNeedle valve assemblyMain jetMain nozzle/O-ring

111

1/1111

1/111

1/1


Refer to “CARBURETOR ASSEMBLY” section.

1

10

23456789

11

5-3

CARBURETOR CARB


Pilot screw assemblyPilot jetThrottle stop screw assemblyStarter plunger assemblyScrew/gasketHeater unit /washer

1111

1/11/1


Refer to “CARBURETOR ASSEMBLY” section.

121314151617

5-4

CARBURETOR CARB

CAUTION:

New

SR******

CARBURETOR ASSEMBLY

Do not use a wire for cleaning.Before assembling, wash all parts in cleanpetroleum based solvent.

Always use a new gasket.

1. Install:Pilot jet 1Pilot screw assembly 2

Pilot screw (turn out):2 turns out

2. Install:O-ring Main nozzle 1Main jet 2

3. Install:Valve seat 1Needle valve 2

4. Install:Float 1Float pin 2

5-5

CARBURETOR CARB

***************************************

***************************************

YP600060

FUEL LEVEL ADJUSTMENT1. Measure:Fuel level aOut of specification Adjust.

Fuel level:2.5 3.5 mm below the float chamber line

Measurement and adjustment steps:Place the motorcycle on a level surface.Put a garage jack under the engine to ensurethat the carburetors are positioned vertically.

Connect the fuel level gauge 1 to the drainpipe 2 .

Fuel level gauge:90890-01312

Loosen the drain screw 3 .Hold the gauge vertically next to the floatchamber line.

Measure the fuel level a with the gauge. If the fuel 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 float level by bending thefloat tang 4 slightly.

Install the carburetor.Recheck the fuel level.

CARB

CHAPTER 6.CHASSIS

FRONT WHEEL AND BRAKE DISC 6-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . FRONT WHEEL DISASSEMBLY 6-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FRONT WHEEL INSPECTION 6-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BRAKE DISC INSPECTION 6-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FRONT WHEEL ASSEMBLY 6-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FRONT WHEEL INSTALLATION 6-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . WHEEL STATIC BALANCE ADJUSTMENT 6-6. . . . . . . . . . . . . . . . . . . .

FRONT BRAKE 6-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BRAKE PAD 6-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BRAKE PAD REPLACEMENT 6-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MASTER CYLINDER 6-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MASTER CYLINDER INSPECTION 6-12. . . . . . . . . . . . . . . . . . . . . . . . . . . MASTER CYLINDER ASSEMBLY 6-12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . MASTER CYLINDER INSTALLATION 6-13. . . . . . . . . . . . . . . . . . . . . . . . . CALIPER 6-15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BRAKE CALIPER DISASSEMBLY 6-17. . . . . . . . . . . . . . . . . . . . . . . . . . . . CALIPER INSPECTION 6-17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BRAKE CALIPER ASSEMBLY 6-17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CALIPER INSTALLATION 6-18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

REAR WHEEL, REAR BRAKE AND DRIVE CHAIN 6-20. . . . . . . . . . . . . . . . REAR WHEEL AND REAR BRAKE 6-20. . . . . . . . . . . . . . . . . . . . . . . . . . . DRIVE CHAIN 6-24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . REAR WHEEL DISASSEMBLY 6-25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . REAR WHEEL INSPECTION 6-25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . REAR BRAKE INSPECTION 6-25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DRIVE CHAIN INSPECTION 6-26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BRAKE SHOE PLATE ASSEMBLY 6-27. . . . . . . . . . . . . . . . . . . . . . . . . . . . REAR WHEEL ASSEMBLY 6-28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DRIVE CHAIN INSTALLATION 6-28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

FRONT FORK 6-29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FRONT FORK DISASSEMBLY 6-31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FRONT FORK INSPECTION 6-31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FRONT FORK ASSEMBLY 6-32. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FRONT FORK INSTALLATION 6-34. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

HANDLEBAR 6-35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HANDLEBAR REMOVAL 6-37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HANDLEBAR INSPECTION 6-37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HANDLEBAR INSTALLATION 6-37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

STEERING 6-39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . UNDER BRACKET 6-39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . STEERING REMOVAL 6-41. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . STEERING INSPECTION 6-41. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

STEERING INSTALLATION 6-42. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

REAR SHOCK ABSORBER AND SWINGARM 6-43. . . . . . . . . . . . . . . . . . . . SWINGARM INSPECTION 6-44. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-1

FRONT WHEEL AND BRAKE DISC CHAS


12

34567

Front wheel and brake disc removal

Speedometer cableAxle pinch bolt

Wheel axleFront wheel assemblyCollarMeter gear unit assemblyBrake disc

11

11111


Loosen the axle pinch bolt.NOTE:

59 Nm (5.9 mkg)

20 Nm (2.0 mkg)

23 Nm (2.3 mkg)

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

Refer to “FRONT WHEEL INSTALLATION” section.

Refer to “FRONT WHEEL ASSEMBLY”section.Reverse the removal procedure forinstallation.

WARNING

EB700000

CHASSISFRONT WHEEL AND BRAKE DISC

6-2


Front wheel disassemblyOil seal

BearingSpacerSpacer flangeBearing


1

1111

Disassemble the parts in order.Refer to “FRONT WHEEL ASSEMBLY”section.

Refer to “FRONT WHEEL DISASSEMBLY/ASSEMBLY” section.

Reverse the disassembly procedure forreassembly.

1

2345

6-3


CAUTION:

WARNING

NOTE:

NOTE:

T******

FRONT WHEEL DISASSEMBLY1. Remove:Bearings 1SpacerRemove the bearings using a general bear-ing puller 2 .

Handle the wheel with care not to damagethe brake disc. If the brake disc is damaged,replace.

T700021

FRONT WHEEL INSPECTION1. Inspect:Front wheel axle(by rolling it on a flat surface)Bends Replace.

Do not attempt to straighten a bent axle.

Wheel axle bending limit:0.25 mm

2. Inspect:Front tireWear/damage Replace.Refer to “TIRE INSPECTION” in CHAPTER3.

Front wheelRefer to “WHEEL INSPECTION” in CHAP-TER 3.

3. Check:SpokesBends/damage Replace.Loose spokes Retighten.Turn the wheel and tap the spokes with ascrewdriver.

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

4. Tighten:Loose spokesNipple

Check the front wheel runout after tighteningthe spokes.

6-4


NOTE:

5. Measure:Front wheel runoutOver the specified limits Replace.

Front wheel runout limits:Radial 1 : 2.0 mmLateral 2 : 2.0 mm

6. Inspect:Front wheel bearingsBearings allow free play in the wheel hub orthe wheel does not turn smoothly Replace.

Oil sealsWear/damage Replace.

7. Inspect:CollarGrooved wear Replace the collar and theoil seal as a set.

YP******

BRAKE DISC INSPECTION1. Measure:Brake disc deflection

Maximum deflection:0.15 mm

Out of specification Replace.2. Measure:Brake disc thickness

Brake disc thickness:4.0 mm

Minimum thickness:3.5 mm

Out of specification Replace.YP******

FRONT WHEEL ASSEMBLY1. Install:Bearing 1Spacer 2Spacer flange 3Bearing 4Oil seal 5

Apply the lithium soap base grease on thebearing and oil seal lip when installing.

Use a socket that matches the outside diame-ter of the race of the bearing.

Always use a new oil seal. Install the oil seal with its manufacturer’smarks or numbers facing outward.

6-5


CAUTION:

23 Nm (2.3 mkg)

NOTE:

NOTE:

NOTE:

Do not strike the inner race of balls of thebearing. Contact should be made only withthe outer race.

2. Install:Brake disc 1

Tighten the bolts (brake disc) in stage using acrisscross pattern.

SR700030

FRONT WHEEL INSTALLATIONReverse the “REMOVAL” procedure.Note the following points.1. Lubricate:Front wheel axleBearingsOil seal (lips)Drive/driven gear (speedometer)

Recommended lubricant:Lithium soap base grease

2. Install:Speedometer gear unit 1

Make sure that the wheel hub and thespeedometer gear unit are installed with the twoprojections a meshed into the two slots b .

3. Install:Front wheel

Make sure that the slot a in the speedometergear unit fits over the stopper b on the front forkouter tube.

6-6


59 Nm (5.9 mkg)

20 Nm (2.0 mkg)

CAUTION:

WARNING

NOTE:

***************************************

***************************************

4. Tighten:Front wheel axleAxle pinch bolt

Before tightening the wheel axle, stroke thefront fork several times to check for properfork operation.

Make sure that the brake hose is routedproperly.

YP700040

WHEEL STATIC BALANCE ADJUSTMENT

After replacing the fire and/or rim, the wheelstatic balance should be adjusted.

Adjust the front wheel static balance with thebrake disc installed.

1. Remove:Balancing weight 1

2. Set:Wheel(on a suitable stand)

3. Find:Heavy spot

Procedure:a. Spin the wheel and wait for it to rest.b. Put an “X1” mark on the wheel’s bottom spot.c. Turn the wheel so that the “X1” mark is 90

up.d. Release the wheel and wait for it to rest.

Put an “X2” mark on the wheel’s bottom spot.e. Repeat the above b., c., and d. several times

until all marks come to the same spot.f. This spot is the wheel’s heavy spot “X”.

6-7


***************************************

NOTE:

***************************************

***************************************

***************************************

4. Adjust:Wheel static balance

Adjusting steps: Install a balancing weight 1 on the rim exactlyopposite to the heavy spot “X”.

Start with the smallest weight.

Turn the wheel so that the heavy spot is 90up.

Check that the heavy spot is at rest there. Ifnot, try another weight until the wheel is bal-anced.

5. Check:Wheel static balance

Checking steps:Turn the wheel so that it comes to each pointas shown.

Check that the wheel is at rest at each point.If not, readjust the front wheel static balance.

6-8

FRONT BRAKE CHAS


123

Brake pad removalBolt (caliper support bolt)Brake padsPad support

121


Refer to “BRAKE PAD REPLACEMENT”section.


23 Nm (2.3 mkg)

FRONT BRAKEBRAKE PAD

6-9

FRONT BRAKE CHAS

NOTE:

NOTE:

CAUTION:

23 Nm (2.3 mkg)

SR702010

BRAKE PAD REPLACEMENT

It is not necessary to disassemble the brake cal-iper and brake hose to replace the brake pads.

1. Remove:Bolt (caliper support bolt) 1Move the direction brake caliper 2 to the ar-row mark.

2. Remove:Brake pads 1

Install new brake pad springs 2 when thebrake pads have to be replaced.

Replace the brake pads as a set if either isfound to be worn to the wear limit.

3. Push the caliper piston into the brake caliperby finger.

When pushing the caliper piston into thebrake caliper, brake fluid level in reservoirtank is increasing higher.

4. Install:Brake pad 1Install the brake pad, and move the brakecaliper to the allow mark direction.

5. Install:Bolt (caliper support bolt)

6. Inspect:Brake fluid levelRefer to “BRAKE FLUID LEVEL INSPEC-TION” section in CHAPTER 3.

7. Check:Brake lever operationSoft spongy feeling Bleed the brake sys-tem.Refer to “AIR BLEEDING (HYDRAULICBRAKE SYSTEM)” in CHAPTER 3.

6-10

FRONT BRAKE CHAS


12345678

Master cylinder removalDrain the brake fluidRear view mirror (right)Brake lever/compression springBrake switchUnion boltPlate washerBrake hoseBracket (master cylinder)Master cylinder

11/1112111


Refer to “MASTER CYLINDER INSTALLATION” section.


2 Nm (0.2 mkg)

9 Nm (0.9 mkg)

30 Nm (3.0 mkg)

MASTER CYLINDER

6-11

FRONT BRAKE CHAS

Master cylinder disassemblyRubber bootsCirclipMaster cylinder kitSpring


111


Refer to “MASTER CYLINDER ASSEMBLY” section.


1234

6-12

FRONT BRAKE CHAS

WARNING

YP702040

MASTER CYLINDER INSPECTION1. Inspect:Master cylinder piston 1Wear/scratches Replace the master cyl-inder kit.

Master cylinder cup 2Cracks/damage Replace.

2. Inspect:Master cylinderScratches/wear/damage Replace themaster cylinder assembly.

3. Inspect:DiaphragmWear/damage Replace.

YP******

MASTER CYLINDER ASSEMBLY

All internal brake components should becleaned and lubricated with new brakefluid only before installation.


Replace the piston seals and dust sealswhenever a master cylinder is disas-sembled.

1. Install:Spring 1Install the spring with its smaller diameter tothe master cylinder piston.

Master cylinder kit 2

6-13

FRONT BRAKE CHAS

A

New

9 Nm (0.9 mkg)

CAUTION:

New

New30 Nm (3.0 mkg)

NOTE:

CAUTION:

2. Install:Circlip 1 Install the circlip securely into the master cyl-inder groove.

Rubber boot 2

YP******

MASTER CYLINDER INSTALLATION1. Install:Master cylinder 1Master cylinder bracket 2

Install the master cylinder bracket 2 withthe “UP” mark facing upward.

2. Install:Plain washer 1 Brake hose 2Plain washer 3 Union bolt 4

Install the brake hose as shown.

3. Fill:Reservoir tank


Brake fluid may damage painted surfaces orplastic parts. Always clean up spilled brakefluid immediately.

6-14

FRONT BRAKE CHAS

WARNING

Use only designated quality brake fluid:Otherwise, the rubber seals may deterio-rate, causing leakage and poor brake per-formance.

Refill with the same type of brake fluid:mix-ing fluids may result in a harmful chemicalreaction and lead to poor performance.

Be careful that water does not enter the sig-nificantly lower the boiling point of thefluid may result in vapor lock.

4. Air bleed:Brake systemRefer to “AIR BLEEDING” section in CHAP-TER 3.

5. Inspect:Brake fluid levelBrake fluid level is under the “LOWER” levelline Fill up.Refer to “BRAKE FLUID INSPECTION” section in CHAPTER 3.

6-15

FRONT BRAKE CHAS


123456

Caliper removalDrain teh brake fluidBrake hose holderUnion boltPlain washerBrake hoseCaliper support boltCaliper assembly

111111


Refer to “CALIPER INSTALLATION”section.

23 Nm (2.3 mkg)

30 Nm (3.0 mkg)

40 Nm (4.0 mkg)

Reverse the removal procedure forinstallation

CALIPER

6-16

FRONT BRAKE CHAS


Caliper disassemblyBrake padCaliper pistonDust sealPiston sealBleed screw/Cap

2221

Disassemble the parts i order.Refer to “BRAKE PAD” section.

Refer to “BRAKE CALIPER DISASSEMBLY/ASSEMBLY” section.


6 Nm (0.6 mkg)

1234

6-17

FRONT BRAKE CHAS

NOTE:

***************************************

WARNING

***************************************

WARNING

SR******

BRAKE CALIPER DISASSEMBLY

Before disassembling either brake caliper,drain the brake fluid from the brake hose, mas-ter cylinder, brake caliper and reservoir tank.

1. Remove:Brake caliper pistonsCaliper piston seals/dust seals

Removal steps:Use a piece of wood 1 to secure the smallerside caliper pistons.

To force out the bigger side caliper pistonsfrom the brake caliper body blow compressedair into the hose joint opening a .

Remove the caliper piston seals and reinstallthe bigger side caliper pistons.

Repeat the previous steps to force out thesmaller side caliper pistons from the brake cal-iper body.

Never try to pry out the caliper piston.

YP******

CALIPER INSPECTION1. Inspect:Caliper cylinder 1Caliper piston 2Scratches, wear Replace caliper assem-bly.

EB702050

BRAKE CALIPER ASSEMBLY

All internal brake components should becleaned and lubricated with new brakefluid only before installation.


Replace the caliper piston seals whenevera brake caliper is disassembled.

6-18

FRONT BRAKE CHAS

New

New

WARNING

40 Nm (4.0 mkg)

23 Nm (2.3 mkg)

New

30 Nm (3.0 mkg)

CAUTION:

CAUTION:

1. Install:Piston seals 1 Dust seal 2

Always use new caliper piston seals.

2. Install:Caliper piston 1Apply brake fluid to the outer surface andinstall.

YP******

CALIPER INSTALLATION1. Install:Caliper 1Caliper support bolt 2

Brake hose 3Plain washer 4 Union bolt 5

When installing the brake hose to the cali-per, lightly touch the brake hose with thestopper a on the caliper.

2. Fill:Reservoir tank


Brake fluid may damage painted surfaces orplastic parts. Always clean up spilled brakefluid immediately.

6-19

FRONT BRAKE CHAS

WARNING

Use only the designated quality brakefluid: other brake fluids may deteriorate therubber seals, causing leakage and poorbrake performance.

Refill with the same type of brake fluid:mixing brake fluids may result in a harmfulchemical reaction and lead to poor brakeperformance.

Be careful that water does not enter themaster cylinder when refilling. Water willsignificantly lower the boiling point of thebrake fluid and may result in vapor lock.

3. Air bleed:Brake systemRefer to “AIR BLEEDING (HYDRAULICBRAKE SYSTEM)” in CHAPTER 3.

4. Inspect:Brake fluid levelBrake fluid level is under the “LOWER” levelline Fill up.Refer to “BRAKE FLUID LEVEL INSPEC-TION” in CHAPTER 3.

6-20

REAR WHEEL, REAR BRAKE AND DRIVE CHAIN CHAS


123456

789

1011

Rear wheel and rear brake removalAdjusterBrake rodPinCompression springCotter pinTension bar

Chain caseAxle nutChain pullerWheel axleCollar

111111

11211


Bend the end after installing.NOTE:

40 Nm (4.0 mkg)

65 Nm (6.5 mkg)

20 Nm (2.0 mkg)

REAR WHEEL, REAR BRAKE AND DRIVE CHAINREAR WHEEL AND REAR BRAKE

6-21

REAR WHEEL REAR BRAKE AND DRIVE CHAIN CHAS


12131415161718

Rear wheel assemblyCollarShoe plateNut (driven sprocket)CirclipWasherDriven sprocket

1114111


Refer to “REAR WHEEL ASSEMBLY” section.

65 Nm (6.5 mkg)

20 Nm (2.0 mkg)

40 Nm (4.0 mkg)

6-22



Rear wheel disassemblyBearingCollarSpacerOil sealBearing

11111


Refer to “REAR WHEEL DISASSEMBLY/ASSEMBLY” section.


12345

6-23



Brake shoe plate disassemblyBrake shoe kitTension springsCam leverIndicator plateCamshaft

22111


Refer to “BRAKE SHOE PLATE ASSEMBLY” section.


12345

9 Nm (0.9 mkg)

6-24



1

23456789

Drive chain removalChain case

Axle nut

Shift pedalSprocket coverSprocket holderClipPlateChain jointDrive chainDrive sprocket

1

11111111

Remove the parts in order.Refer to “REAR WHEEL, REAR BRAKEAND DRIVE CHAIN” section.NOTE:

Refer to “DRIVE CHAIN INSTALLATION”section.

Loosen the axle nut and slacken thedrive chain.


7 Nm (0.7 mkg)

10 Nm (1.0 mkg)

65 Nm (6.5 mkg)

8 Nm (0.8 mkg)

DRIVE CHAIN

6-25


WARNING

T******

REAR WHEEL DISASSEMBLY1. Remove:Bearings 1Spacer 2Collar 3Refer to “FRONT WHEEL”.

SR701020

REAR WHEEL INSPECTION1. Inspect:Rear wheel axleRear wheelRear wheel bearingsOil sealsRefer to “FRONT WHEEL”.

2. Inspect:Clutch hub damperWear/damage Replace.

SR701021

REAR BRAKE INSPECTION1. Inspect:Brake lining surfaceWear/damage Replace.

2. Measure:Brake lining thickness aOut of specification Replace.

Brake lining thickness:Standard:

4 mmLimit:

2 mm

When inspecting the brake lining, do notspill oil or grease on the brake lining.

3. Inspect:Brake drum inner surfaceOilScratchesWear/damage Replace.

4. Measure:Brake drum inside diameter aOut of specification Replace.

Brake drum inside diameter:Standard:

110 mmLimit:

111 mm

6-26


NOTE:

5. Inspect:Cam shaft face

T701020

DRIVE CHAIN INSPECTION1. Inspect:Drive chain stiffnessStiffness Clean and lubricate or replace.

2. Inspect:Drive chain 1Driven sprocket 2More than 1/2 tooth a wear Replace thedrive chain.Use new driven sprocket.

3. Measure:10 link length a (drive chain)Out of specification Replace the drivechain.

10 link length limit:122 mm

Tighten the drive chain with a finger beforemeasuring.

10 link length is the distance between the inside edge of roller 1 and 11 as shown.

10 link length measurement should be done attwo or three different places.

6-27


***************************************

***************************************9 Nm (0.9 mkg)

NOTE:

New

NOTE:

WARNING

4. Clean:Drive chainPut it in kerosene, and brush off as much dirtas possible. Then remove the drive chainfrom the kerosene and dry it.

Drive chain lubricant:Engine oil

SR******

BRAKE SHOE PLATE ASSEMBLY1. Install:Camshaft 1 Indicator plate 2

Installation steps:Align the projection a on the indicator platewith the camshaft notch b and install.

Check the proper position of the brake shoe.

2. Install:Cam lever 1

Align the punch mark c on the cam shaft withthe mark made on the cam lever d .

Apply lithium soap base grease onto the brakecam shaft and pin.

3. Install:Brake shoes 1Tension springs 2

When installing the springs and brake shoes,take care not to damage the springs.

Replace the tension spring as a set when re-place the brake shoes.

After installing the rear brake cam shaft, re-move the excess grease.

6-28


NOTE:

CAUTION:

New40 Nm (4.0 mkg)

New

CAUTION:

SR******

REAR WHEEL ASSEMBLY1. Install:Bearing 1Spacer 2Collar 3Bearing 4

Apply the lithium soap base grease on thebearing and oil seal lip when installing.

Use a socket that matches the outside diame-ter of the race of the bearing.

Always use a new oil seal. Install the oil seal with its manufacturer’smarks or numbers facing outward.

Do not strike the inner race of balls of thebearing. Contact should be made only withthe outer race.

2. Install:Driven sprocket 1Washer 2Circlip 3 Nut 4

T*****

DRIVE CHAIN INSTALLATION1. Install:Drive chain 1Chain joint 2Plate 3

2. Install:Clip 1

Be sure to install the chain joint clip to thedirection as shown.

6-29

FRONT FORK CHAS


123456

78

Front fork removalFront wheel

Brake hose holderCaliperFront fenderCoverBolt/washerBolt (under bracket)

Front fork assembly (left)Front fork assembly (right)

1111

1/11

11

Remove the parts in order.Refer to “FRONT WHEEL AND BRAKEDISC” section.

Loosen the bolt.NOTE:

Refer to “FRONT FORK INSTALLATION”section.


48 Nm (4.8 mkg)

30 Nm (3.0 mkg)

40 Nm (4.0 mkg)

FRONT FORK

6-30

FRONT FORK CHAS

10


Front fork disassemblyCap bolt /O-ringCollar/washerFork springDust coverRetaining clipWasher (oil seal)Inner tube assemblyOil sealPiston metalDamper rodOuter tube

1/11/1111111111

Drain the fork oil.NOTE:

Refer to “FRONT FORK DISASSEMBLY/ASSEMBLY” section.

Refer to “FRONT FORK ASSEMBLY” section.



123456789

11

65 Nm (86.5 mkg)

6-31

FRONT FORK CHAS

CAUTION:

***************************************

CAUTION:

***************************************

WARNING

SR******

FRONT FORK DISASSEMBLY1. Remove:Cap bolt 1Collar 2Washer 3Fork spring 4

2. Remove:Dust cover 1Retaining clip 2(using a slotted-head screwdriver)

Washer (oil seal) 3

Take care not to scratch the inner tube.

3. Remove: Inner tube

Removal steps:Hold the fork leg horizontally.Securely clamp the outer tube in a vise withsoft jaws.

Separate the inner tube from the outer tube bypulling forcefully but carefully the inner tube.

Excessive force will damage the oil sealand/or the metal. damaged oil seal and met-al must be replaced.

YP703030

FRONT FORK INSPECTION1. Inspect: Inner tube bending

Inner tube bending limit:0.2 mm

Scratches/bends/damage Replace.

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

6-32

FRONT FORK CHAS

CAUTION:

NOTE:

NOTE:

2. Measure:Fork spring a

Front fork spring free length:326.1 mm

<Wear limit>321 mm

Over the specified limit Replace.

3. Inspect:Rod assembly 1Bends/damage Replace.

The front fork has a built-in piston rod anda very sophisticated internal constructionwhich are particularly sensitive to foreignmaterial.

When disassembling and assembling thefront fork do not allow any foreign materialto enter the oil.

SR******

FRONT FORK ASSEMBLYReverse the “DISASSEMBLY” procedure.Note the following points.

When assembling the front fork be sure to re-place the following parts.* Piston metal* Slide metal* Oil seal* Dust seal

Before assembling the fork, make sure that allof the components are clean.

1. Install:Damper rod 1 Inner tube 2

Install the damper rod into the inner tube beforeinstall to the outer tube.

6-33

FRONT FORK CHAS

New

New

NOTE:

CAUTION:

New

NOTE:

2. Install:Piston metal 1 Oil seal 2 Use the fork seal driver weight 3 and the at-tachment 4 .

Before installing the oil seal 2 , apply lithiumsoap base grease onto the oil seal lips.

Make sure that the oil seal numbered sidefaces upward.

Fork seal driver weight:90890-01400

Attachment:90890-01367

3. Install:Washer (oil seal) 1Retaining clip 2 Dust seal 3

Adjust the retaining clip so that it fits into the out-er tube groove.

4. Inspect: Inner tube operationUnsmooth operation Disassembly and re-check.

5. Fill:Fork oil 1

Oil quantity:0.177 L

Recommended oil:Fork oil 15WT or equivalent

6. After filling up, slowly pump the fork up anddown to distribute the fork oil.

6-34

FRONT FORK CHAS

NOTE:

NOTE:

New65 Nm (6.5 mkg)

NOTE:

48 Nm (4.8 mkg)

30 Nm (3.0 mkg)

7. Measure:Oil level aOut of specification Adjust.

Oil level:165 mm

(from the top of the inner tube fully compressed and without the fork spring)

Hold the fork in an upright position.

8. Install:Front fork spring 1

Install the fork spring with its smaller pitch up-ward.

Before installing the cap bolt, apply grease tothe O-ring.

Temporarily tighten the cap bolt.

9. Install:Plate washerSpacerO-ring Cap bolt

EB70307250

FRONT FORK INSTALLATIONReverse the “REMOVAL” procedure.Note the following points.1. Install:Front fork 1Plate washer 2Temporary tighten the pinch bolts.

Pull up the inner tube until its end flushes the topof the under bracket, then temporarily tightenthe bolt (under bracket lower).

2. Tighten:Cap bolts 3Pinch bolts (under bracket)

6-35

HANDLEBAR CHAS


12

3456789

10

Handlebar removalHeadlight assemblyHandlebar switch lead (left and right),front brake switch lead and clutchswitch leadMaster cylinder bracketMaster cylinderHousing (throttle grip)Throttle cableThrottle grip assemblyHandle bar switch (right)Clutch switchClutch cable

11

11111111


Disconnect the connector.NOTE:

Refer to “HANDLEBAR INSTALLATION”section.

9 Nm (0.9 mkg)

20 Nm (2.0 mkg)

HANDLEBAR

6-36

HANDLEBAR CHAS


1112

131415

Handlebar switch (left)Grip (left)

Lever holder (left)Upper holderHandlebar

11

121

Refer to “HANDLEBAR REMOVAL” section.

Refer to “HANDLEBAR INSTALLATION”section.


9 Nm (0.9 mkg)

20 Nm (2.0 mkg)

6-37

HANDLEBAR CHAS

***************************************

***************************************

WARNING

20 Nm (2.0 mkg)

NOTE:

NOTE:

WARNING

YP******

HANDLEBAR REMOVAL1. Remove:Grip (Left)

Removal steps:Remove the grip end (left).Blow with compressed air between the hadle-bar and adhesive side of the grip to remove.

YP704020

HANDLEBAR INSPECTION1. Inspect:HandlebarBends/Cracks/Damage Replace.

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

SR******

HANDLEBAR INSTALLATION1. Install:Handlebar 1Upper handlebar holder 2

Apply a light coat of lithium soap base greaseonto the handlebar right end.

The upper handlebar holders should beinstalled with the longer side a to the forward,then tighten the front bolt as shown.

2. Install:Handlebar switch (right) 1Grip assemblyThrottle cableCover (throttle grip)

Align the projection a on the handlebar switchwith the hole b in the handlebar.

Check the throttle grip for smooth opera-tion.

6-38

HANDLEBAR CHAS

9 Nm (0.9 mkg)

NOTE:

3. Install:Master cylinder 1Master cylinder bracket 2

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

4. Adjust:Throttle cable free playBrake operation.Refer to “THROTTLE CABLE ADJUST-MENT/BRAKE LEVER ADJUSTMENT”section in CHAPTER 3.

6-39

STEERING CHAS


1234567

89

Under bracket removalFront forkHandlebarFlasher light assembly (left)Flasher light assembly (right)CoverMeter cable/Meter leadMeter assembly/Handlebar crownHornRing nut

Ball race coverUnder bracket

111

1/11/111

11

Remove the parts in order.Refer to “FRONT FORK” section.Refer to “HANDLEBAR” section.

Disconnect the connector.NOTE:

Refer to “STEERING REMOVAL/INSTALLATION” section.

40 Nm (4.0 mkg)1st step:38 Nm (3.8 mkg)2nd step:7 Nm (0.7 mkg)

STEERINGUNDER BRACKET

6-40

STEERING CHAS


1011121314

Ball race (upper)BallBallBall race (center)Ball race (lower)

1221911


Refer to “STEERING REMOVAL/INSTALLATION” section.

40 Nm (4.0 mkg)1st step:38 Nm (3.8 mkg)2ndstep:7 Nm (0.7 mkg)

6-41

STEERING CHAS

WARNING

WARNING

***************************************

***************************************NOTE:

CAUTION:

YP704010

STEERING REMOVAL


Stand the motorcycle on a level surface.

1. Remove:Ring nut 1Use a exhaust and steering nut wrench 2 .

Exhaust and steering out wrench:90890-01268

Securely support the steering shaft so thatthere is no danger of it falling down.

STEERING INSPECTION1. Wash the bearing and ball races with a sol-

vent.2. Inspect:BearingsBall racesPitting/Damage Replace.

Bearing race replacement steps:Remove the ball races on the head pipe usinglong rod 1 and the hammer as shown.

Remove the ball race on the under bracket us-ing the floor chisel 2 and the hammer asshown.

Install the new dust seat and races.

Always replace bearings and races as a set.Replace the dust seal whenever a steeringhead disassembled.

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

6-42

STEERING CHAS

7 Nm (0.7 mkg)

EB704030

STEERING INSTALLATIONReverse the “REMOVAL” procedure.Note the following points.1. Lubricate:Bearings (upper and lower)Ball races

Recommended lubricantLithium-soap base grease

2. Install:Ring nut 1Refer to “STEERING HEAD INSPECTION”section in CHAPTER 3.

6-43

REAR SHOCK ABSORBER AND SWINGARM CHAS


123456789

Rear shock absorber and swingarmremovalRear wheelChain caseDrive chainRear shock absorberNutFootrest assembly (right)Pivot shaftFootrest assembly (left)SwingarmTension barCover (swingarm)Bush

211111112


Refer to “REAR WHEEL, REAR BRAKEAND DRIVE CHAIN” section.


40 Nm (4.0 mkg)

45 Nm (4.5 mkg)

20 Nm (2.0 mkg)

30 Nm (3.0 mkg)

REAR SHOCK ABSORBER AND SWINGARM

6-44

REAR SHOCK ABSORBER AND SWINGARM CHAS

T*****

SWINGARM INSPECTION1. Inspect:Swingarm side playFree play exists Check side clearance.

Swingarm up and down movementUnsmooth movement/bending/rough spots Grease or replace bearings, solid bushesand collars.

CHAPTER 7.ELECTRICAL

ELECTRICAL COMPONENTS 7-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SWITCH INSPECTION 7-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . INSPECTION STEPS 7-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SWITCH CONNECTION AS SHOWN IN THIS MANUAL 7-2. . . . . . . . . SWITCH CONTINUITY INSPECTION 7-3. . . . . . . . . . . . . . . . . . . . . . . . .

IGNITION SYSTEM 7-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CIRCUIT DIAGRAM 7-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TROUBLESHOOTING 7-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ELECTRIC STARTING SYSTEM 7-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CIRCUIT DIAGRAM 7-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . STARTING CIRCUIT OPERATION 7-11. . . . . . . . . . . . . . . . . . . . . . . . . . . . TROUBLESHOOTING 7-12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . STARTER MOTOR 7-16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CHARGING SYSTEM 7-19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CIRCUIT DIAGRAM 7-19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TROUBLESHOOTING 7-20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

LIGHTING SYSTEM 7-23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CIRCUIT DIAGRAM 7-23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TROUBLESHOOTING 7-24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . LIGHTING SYSTEM CHECK 7-25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SIGNAL SYSTEM 7-28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CIRCUIT DIAGRAM 7-28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TROUBLESHOOTING 7-29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SIGNAL SYSTEM CHECK 7-31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7-1

ELECTRICAL COMPONENTS ELEC

15 C.D.I. unit8 Neutral relay9 Thermo switch

10 Sidestand switch11 Rear brake switch12 Neutral switch13 Spark plug cap14 Ignition coil

1 Horn2 Flasher relay3 Main switch4 Starter relay5 Rectifier /Regulator6 Battery7 Fuse holder assembly

EB800000

ELECTRICALELECTRICAL COMPONENTS

7-2

SWITCH INSPECTION ELEC

NOTE:

YP-N

SWITCH INSPECTIONINSPECTION STEPSUsing pocket tester, check switches for continu-ity between their terminals to determine wheth-er they are correctly connected.Replace the switch component if any of thecombinations does not produce the correctreading.


Turn the switch to the “ON”, “OFF” positionsseveral times.

Adjust the pocket tester to correct “0” positionbefore checking switches.

Set the pocket tester selector to “1” Ω.

SWITCH CONNECTION AS SHOWN IN THISMANUALThis manual contains connection charts, likethe one shown on the left, showing the terminalconnections of switches (e.g. the main switch,handlebar switch, brake switch, lighting switchetc.)

The column on the extreme left indicates the dif-ferent switch positions, the top line indicates thecolors of the leads connected to the terminalson the switch.

“—” indicates terminals between whichthere is continuity, i.e. a closed circuit, in the giv-en switch position.

In this chart:“Br and R” have continuity with the switch in the“ON” position.

7-3

1 Clutch switch2 Turn switch3 Dimmer switch4 Horn switch5 Main switch6 Front brake switch

7 Engine stop switch8 Start switch9 Rear brake switch

10 Neutral switch11 Sidestand switch12 Fuse

13 Thermo switch

SWITCH INSPECTION ELEC

SWITCH CONTINUITY INSPECTIONRefer to “SWITCH INSPECTION” and check for continuity between lead terminals.Poor connection, no continuity Correct or replace.* The coupler locations are circled.

7-4

1 C.D.I. magneto6 Main switch

10 Engine stop switch12 C.D.I. unit13 Ignition coil14 Spark plug15 Sidestand switch

IGNITION SYSTEM ELEC

EB802000

IGNITION SYSTEMCIRCUIT DIAGRAM

7-5


NOTE:

1. Spark plug

Check the spark plug condition.Check the spark plug type.Check the spark plug gap.Refer to “SPARK PLUG INSPECTION” sec-tion in CHAPTER 3.

Spark plug gap:0.6 0.7 mm

Standard spark plug:DR8EA/NGK

OUT OF SPECIFICATION

Repair or replace the spark plugMEETSSPECIFICATION

SR802010

TROUBLESHOOTING

IF THE IGNITION SYSTEM FAILS TO OPERATE.(NO SPARK OR INTERMITTENT SPARK)

ProcedureCheck:1. Spark plug2. Ignition spark gap3. Spark plug cap resistance4. Ignition coil5. Pickup coil resistance

6. Source coil resistance7. Main switch8. Engine stop switch9. Sidestand switch

10. Wiring connection(entire ignition system)

Remove the following parts before trouble-shooting.

1) Side cover (left and right)2) Seat3) Fuel tank4) Headlight unit

Use the special tools specified in the troubleshooting section.

Ignition checker:90890-06754


YP*****

7-6


Remove the spark plug cap.Connect the pocket tester (Ω 1k) to thespark plug cap.

When removing the spark plug cap, do notpull the spark plug cap from high tensioncord.Remove Turning counterclockwise.Connect Turning clockwise.

Check the high tension cord when connect-ing the spark plug cap.

When connecting the spark plug cap, cut thehigh tension cord about 5 mm.

NOTE:

Disconnect the spark plug cap from thespark plug.

Connect the ignition checker as shown. Spark plug cap

Turn the main switch to “ON”.Check the ignition spark gap .Check the spark by pushing the starterswitch, and increase the spark gap until amisfire occurs.

2. Ignition spark gap

Minimum spark gap:6 mm

The ignition system is not faulty.

MEETS SPECIFICATION

12

a

OUT OF SPECIFICA-TION OR NO SPARK

3. Spark plug cap resistance

Spark plug cap resistance:10 kΩ (20C)

MEETSSPECIFICATION

Tester (+) lead Spark plug side

Tester (–) lead High tension cord side

Replace the spark plug cap.


1

2

YP*****

YP*****

7-7


Tester (+) lead Spark plug lead

Tester (–) lead Orange Terminal

Disconnect the ignition coil connector fromthe wireharness.

Connect the pocket tester (Ω 1) to theignition coil.

Check if the primary coil has the specified re-sistance.

4. Ignition coil resistance

Secondary coil resistance:5.68 8.52 kΩ (20C)

BOTH MEETSPECIFICATION

Tester (+) lead Orange Terminal

Tester (–) lead Ground Terminal

Replace the ignition coil.


1

2

Primary coil resistance:0.32 0.48 Ω (20C)

1

2

Connect the pocket tester (Ω 1k) to theignition coil.

Check the secondary has the specified re-sistance.

YP*****

7-8

Tester (+) lead White Terminal

Tester (–) lead Red Terminal

Tester (+) lead Brown Terminal

Tester (–) lead Green Terminal

Disconnect the pickup coil coupler from thewireharness.

Connect the pocket tester (Ω 100) to thepickup coil coupler.

5. Pickup coil resistance

Replace the pickup coil.


Pickup coil resistance:659 984 Ω (20C)

1

2

Check the pickup coil has the specified re-sistance.

MEETSSPECIFICATION

Disconnect the source coil coupler from thewireharness.

Connect the pocket tester (Ω 100) to thecharging coil coupler.

6. Source coil resistance

Source coil resistance:624 936 Ω (20C)

1

2

Check the source coil has the specified re-sistance.

Replace the source coil.


MEETSSPECIFICATION

Refer to “SWITCH INSPECTION” section.

7. Main switch

CONTINUITY

Replace the main switch.

NO CONTINUITY


YP******

T******

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7-9



8. Engine stop switch

Replace the handlebar switch (right).

NO CONTINUITY

CONTINUITY


9. Sidestand switch

Replace the sidestand switch

NO CONTINUITY

CONTINUITY

Check the connection of the entire ignitionsystem.Refer to “CIRCUIT DIAGRAM”.

10.Wiring connection

Correct.

POOR CONNECTIONS

CORRECT

Replace the C.D.I. unit.

YP*****

YP*****

YP*****

7-10

3 Starter relay4 Battery5 Fuse6 Main switch10 Engine stop switch11 Start switch15 Clutch switch16 Sidestand switch17 Neutral relay24 Neutral switch38 Starter motor

ELECTRIC STARTING SYSTEM ELEC

EB80300

ELECTRIC STARTING SYSTEMCIRCUIT DIAGRAM

7-11

ELECTRICAL STARTING SYSTEM ELEC

SR******

STARTING CIRCUIT OPERATIONThe starting circuit on this model consists of thestarter motor, starter relay, and the neutral relay.If the engine stop switch and the main switchare both closed, the starter motor can operateonly if:

The transmission is in neutral (the neutralrelay is closed).

or if

The clutch lever is pulled to the handlebar(the clutch switch is closed) and the side-stand is up (the sidestand switch is closed).

WHEN THE TRANSMISSION IS INNEUTRAL

WHEN THE SIDESTAND IS UP ANDTHE CLUTCH LEVER IS PULLEDIN

1 Battery2 Main fuse3 Main switch4 Engine stop switch5 Neutral relay6 Clutch switch7 Sidestand switch8 Neutral switch9 Start switch10 Starter relay11 Starter motor

7-12


NOTE:

1. Fuse


CONTINUITY

NO CONTINUITY

Replace the fuse.

2. Battery

Check the battery condition.Refer to “BATTERY INSPECTION” sectionin CHAPTER 3.

Specific gravity:1.280 at 20C

CORRECT Refill the battery fluid.Clean battery terminals.Recharge or replace the battery.

INCORRECT

YP803020

TROUBLESHOOTING

IF THE STARTER MOTOR FAILS TO OPERATE.

ProcedureCheck:1. Fuse2. Battery3. Starter motor4. Starter relay5. Neutral relay6. Main switch

7. Engine stop switch8. Neutral switch9. Sidestand switch

10. Clutch switch11. Start switch12. Wiring connection (entire starting system)


1) Side cover (left and right)2) Headlight unit3) Seat4) Fuel tank

Use the special tools specified in the trouble-shooting section.


YP******

YP******

7-13


Connect the battery positive terminal and starter motor cable using a jumperlead *.

Check the starter motor operation.

*

1

3. Starter motor

23

MOVES

DOES NOT MOVE

Repair or replace the starter motor.

4. Starter relay

Disconnect the relay unit coupler from thewireharness.

Connect the pocket tester (Ω 1) and bat-tery (12 V) to the relay unit coupler terminals.

Battery (+) lead Blue/White terminal

Battery (–) lead Red/White terminal

1

2

Check the starter relay for continuity.

Tester (+) lead terminalTester (–) lead terminal

34

CONTINUITY

NO CONTINUITY

Replace the starter relay.

WARNING

YP******

YP******

A wire used as a jumper lead must have theequivalent capacity as that of the batterylead or more, otherwise it may burn.

This check is likely to produce sparks, sobe sure that no flammable gas or fluid is inthe vicinity.

7-14


1

2

3

4

5. Neutral relay

Remove the relay from the frame.Connect the pocket tester (Ω 100) to theBattery and the relay connecter.

Tester (+) lead Terminal 1

Tester (–) lead Terminal 3

Battery (+) lead Terminal 2

Battery (–) lead Terminal 4

Check the Terminal 1 and 3 for continuity.

CONTINUITY

NO CONTINUITY

Replace the neutral relay.

6. Main switch


CONTINUITY

NO CONTINUITY

Replace the main switch

7. Engine stop switch


CONTINUITY

NO CONTINUITY


8. Neutral switch


NO CONTINUITY (at NEUTRAL position)

CONTINUITY(at NEUTRAL position) Replace the neutral switch.

9. Sidestand switch


CONTINUITY

NO CONTINUITY

Replace the sidestand switch.

YP******

YP******

YP******

YP******

YP******

7-15


10.Clutch switch


CONTINUITY

NO CONTINUITY

Replace the clutch switch.

11.Start switch


CONTINUITY

NO CONTINUITY


12.Wiring connection

Check the connections of the entire startingsystem.Refer to “CIRCUIT DIAGRAM”.

POOR CONNECTION

Correct.

YP******

YP******

YP******

7-16


123

Starter motor removalDrain the engine oil

Crankcase cover (right)

Starter motor leadStarter motorO-ring

111

Remove the parts in order.Refer to “ENGINE OIL REPLACEMENT”section in CHAPTER 3.Refer to “CLUTCH REMOVAL” section inCHAPTER 4.


Refer to “Assembly” section.

7 Nm (0.7 mkg)

Starter motor disassemblyFront bracketWasher setRear bracketWasher setBrush holder/brushArmature coil

111111



123456


STARTER MOTOR

7-17


NOTE:

A

B

YP803034

Inspection and repair1. Inspect:CommutatorDirt Clean it with #600 grit sandpaper.

2. Measure:Commutator diameter a

Commutator wear limit:27 mm

Out of specification Replace the startermotor

3. Measure:Mica undercut a

Mica undercut:0.7 mm

Out of specification Scrape the mica to theproper value (a hacksaw blade can beground to fit).

The mica insulation of the commutator must beundercut to ensure proper operation of commu-tator.

4. Inspect:Armature coil resistances(installation/continuity)Defects Replace the starter motor.If commutator is dirty, clean it with sandpa-per.

Goodcondition Bad condition

: Continuity: No continuityBad condition Replace.

5. Measure:Brush length aOut of specification Replace.

Brush length wear limit:3.5 mm

7-18


NOTE:

New

3 Nm (0.3 mkg)

NOTE:

6. Measure:Brush spring forceFatigue/out of specification Replace as aset.

Brush spring force:540 660 g

7. Inspect:Oil sealWear/damage Replace.

YP******

AssemblyReverse the “Disassembly” procedure.Note the following points.1. Install:Brush holder 1

Align the lib on the brush holder with the slot aon the bracket, before assembly.

2. Install:Washer set 1Armature coil 2

3. Install:Ring 1 Stator assembly 2Washer set 3Front bracket

Apply molybdenum grease lightly on to thebearings of the starter motor.

Align the match marks on the yoke with thematch marks on the brackets.

7-19

1 C.D.I. magneto2 Rectifier /Regulator4 Battery5 Fuse

CHARGING SYSTEM ELEC

YP804000

CHARGING SYSTEMCIRCUIT DIAGRAM

7-20


NOTE:

1. Fuse


CONTINUITY

NO CONTINUITY

Replace the fuse.

2. Battery



CORRECT

INCORRECT

Refill the battery fluid.Clean battery terminals.Recharge or replace the battery.

YP804010

TROUBLESHOOTING

IF THE BATTERY IS NOT CHARGED

ProcedureCheck:1. Fuse2. Battery3. Charging voltage

4. Stator coil resistance5. Wiring system (entire charging system)


1) Side cover (left and right)2) Seat3) Fuse


Engine tachometer90890-03113


YP******

YP******

7-21


Tester (+) lead Battery (+) terminal

Tester (–) lead Battery (–) terminal

1

2

3. Charging voltage

Connect the engine tachometer to the sparkplug lead.

Connect the pocket tester (DC20V) to thebattery.

Measure the battery terminal voltage.Start the engine and accelerate to about5,000 r/min.

Check the terminal voltage.

Charging voltage:14.5 V at 5,000 r/min

NOTE:Use a fully charged battery.

OUT OFSPECIFICATION

MEETS SPECIFICATION

The charging circuit is not faulty.Replace the battery.

4. Stator coil resistance

Remove the C.D.I. magneto coupler fromwireharness.

Connect the pocket tester (Ω 1) to the sta-tor coil.

Tester (+) lead White terminalTester (–) lead White terminal

Measure the stator coil resistance.

Stator coil resistance:0.48 0.72 Ω (20C)

MEETSSPECIFICATION


Replace the stator coil.

Left side Right side

YP******

YP******

7-22

5. Wiring connection

Check the entire charging system for connec-tions.Refer to “CIRCUIT DIAGRAM” section.

CORRECT

Replace the rectifier/regulator.

POOR CONNECTION

Correct.


YP******

7-23

4 Battery5 Fuse6 Main switch22 High beam indicator light23 Meter light26 Tail /Brake light30 Auxiliary light34 Lights switch36 Dimmer switch39 Headlight

LIGHTING SYSTEM ELEC

EB804000

LIGHTING SYSTEMCIRCUIT DIAGRAM

7-24


NOTE:

1. Fuse


CONTINUITY

NO CONTINUITY

Replace the fuse.

2. Battery



CORRECT

INCORRECT


3. Main switch


CONTINUITY

NO CONTINUITY


YP805010

TROUBLESHOOTING

IF THE HEADLIGHT, AUXILIARY LIGHT, HIGH BEAM INDICATOR LIGHT,TAILLIGHT AND/OR METER LIGHT FAIL TO COME ON.

ProcedureCheck:1. Fuse2. Battery3. Main switch

4. Lights switch5. Dimmer switch6. Wiring connection (entire lighting system)


1) Seat2) Fuel tank3) Side cover (left and right)4) Headlight unit



YP******

YP******

YP******

7-25

Headlight:Tester (+) lead Green or Yellow leadTester negative (–) lead Black lead

High beam indicator light:Tester (+) lead Yellow leadTester (–) lead Black lead

When the dimmer switch is on low beam.When dimmer switch is on high beam.

1

3

45

B

A

4. Lights switch


CONTINUITY

NO CONTINUITY

Replace the handlebar switch (left).

5. Dimmer switch


CONTINUITY

NO CONTINUITY

Replace the handlebar switch (left).


Check the connections of the entire lightingsystem.Refer to “WIRING DIAGRAM”.

CORRECT

Check the condition of each of the lightingsystem’s circuits.Refer to “LIGHTING SYSTEM CHECK”

POOR CONNECTIONS

Correct.

1. Bulb and bulb socket


CONTINUITY

NO CONTINUITY

Replace the bulb and/or bulb socket.

2. Voltage

Connect the pocket tester (DC20V) to theheadlight and high beam indicator light cou-plers.

B

2


YP******

YP******

YP******

SR805020

LIGHTING SYSTEM CHECK1. If the headlight and the high beam indicator light fail to come on.

7-26


Tester (+) lead Blue terminal

Tester (–) lead Black terminal

Turn the main switch to on position.Turn the lights switch to on position.Turn the dimmer switch to low beam or highbeam.

Check for voltage (12 V) on the lead at bulbsocket connectors.

1

2

MEETSSPECIFICATION

This circuit is not faulty.


The wiring circuit from the main switch to bulbsocket connector is faulty. Repair.



CONTINUITY

2. Voltage

Connect the pocket tester (DC20V) to thebulb socket coupler.

Turn the main switch to on.Turn the lights switch to on position.Turn the dimmer switch to low beam or highbeam.

Check the voltage (12 V) of the leads on thebulb socket connector.

MEETSSPECIFICATION


NO CONTINUITY



The wiring circuit from main switch to bulbsocket is faulty. Repair.

SR805021

2. If the meter light fails to come on.

7-27

Tester (+) lead Blue/Red terminal

Tester (–) lead Black terminal 2

Tester (+) lead Blue terminal

Tester (–) lead Black terminal

1

2

1



CONTINUITY

2. Voltage

Connect the pocket tester (DC20V) to thebulb socket connector.


Check the voltage (12 V) on the bulb socketconnector.

MEETSSPECIFICATION


NO CONTINUITY



The wiring circuit from main switch to bulbconnector is faulty. Repair.



CONTINUITY

2. Voltage



Check the voltage (12 V) on the bulb socketconnector.

MEETSSPECIFICATION


NO CONTINUITY



The wiring circuit from main switch to bulbconnector is faulty. Repair.


YP805022

3. The taillight fails to come on.

SR******

4. The auxiliary light fails to come on.

7-28

4 Battery5 Fuse6 Main switch7 Thermo switch8 Heater unit19 Neutral indicator light20 Turn indicator light (left)21 Turn indicator light (right)24 Neutral switch25 Rear flasher lights26 Tail /Brake light27 Front brake switch

28 Rear brake switch29 Front flasher lights31 Flasher relay32 Horn35 Horn switch37 Turn switch

SIGNAL SYSTEM ELEC

EB806000

SIGNAL SYSTEMCIRCUIT DIAGRAM

7-29

SIGNAL SYSTEM ELEC

NOTE:

1. Fuse


CONTINUITY

NO CONTINUITY

Replace the fuse.

2. Battery



CORRECT

INCORRECT


3. Main switch


CONTINUITY

NO CONTINUITY


YP806010

TROUBLESHOOTING

IF THE FLASHER LIGHT, BRAKE LIGHT AND/OR INDICATOR LIGHT FAIL TO COME ON.IF THE HORN FAILS TO SOUND.

ProcedureCheck:1. Fuse2. Battery

3. Main switch4. Wiring connection (entire signal system)


1) Headlight unit2) Side cover (left and right)

Use the special tools in the troubleshootingsection.


YP******

YP******

YP******

7-30

SIGNAL SYSTEM ELEC

4. Wireharness

Check the connections of the entire signalsystem.Refer to “CIRCUIT SYSTEM WIRING DIA-GRAM” section.

CORRECT

Check condition of each of the signal sys-tem’s circuits.Refer to “SIGNAL SYSTEM CHECK” section.

POOR CONNECTION

Correct.

YP******

7-31

Tester (+) lead Pink terminalTester (–) lead Frame ground

Tester (+) lead Brown terminal Tester (–) lead Frame ground

1

1

1. Horn switch


CONTINUITY

2. Voltage

Connect the pocket tester (DC20V) to thehorn lead.

Turn the main switch to on.Check for voltage (12V) on the “Brown” leadat the horn terminal.

MEETSSPECIFICATION

3. Horn

Connect the pocket tester (DC20V) to thehorn at the “Pink” terminal.

Turn the main switch to on.Check for voltage (12V) on the “Pink” lead toframe ground.

MEETSSPECIFICATION

Adjust or replace horn.

NO CONTINUITY

Replace the left handlebar switch (left).


The wiring circuit from the main switch to thehorn is faulty. Repair.


Replace the horn.

SIGNAL SYSTEM ELEC

YP806020

SIGNAL SYSTEM CHECK1. If the horn fails to sound.

7-32

Tester (+) lead Yellow terminal Tester (–) lead Black terminal

12



CONTINUITY

2. Brake switch (Front/Rear)


3. Voltage


Turn the main switch to on.The brake lever (or brake pedal) is pulled in(down).

Check for voltage (12V) of the “Yellow” leadon the bulb socket connector.

MEETSSPECIFICATION


NO CONTINUITY


NO CONTINUITY

Replace brake switch.



Wiring circuit from the main switch to the bulbsocket connector is faulty. Repair.Refer to “SIGNAL SYSTEM WIRING DIA-GRAM”.

CONTINUITY

SIGNAL SYSTEM ELEC

YP806022

2. If the brake light fails to come on:

7-33

Tester (+) lead Brown/White terminal Tester (–) lead Frame ground

Tester (+) lead Brown terminal Tester (–) lead Frame ground

1

1



CONTINUITY

2. Turn switch


CONTINUITY

3. Voltage

Connect the pocket tester (DC20V) to theflasher relay coupler.

Turn the main switch to on.Check for voltage (12V) of the “Brown” lead at the flasher relay terminal.

1

MEETSSPECIFICATION

4. Flasher relay

Connect the pocket tester (DC20V) to theflasher relay coupler.

Turn the main switch to on.Check for voltage (12V) on the “Brown/White” lead at the flasher relay terminal.

MEETSSPECIFICATION

NO CONTINUITY


NO CONTINUITY

Replace the left handlebar switch (left).


The wiring circuit from main switch to flasherrelay connector is faulty. Repair.


The flasher relay is faulty. Replace.

SIGNAL SYSTEM ELEC

YP806023

3. If the flasher light and/or turn indicator lightfails to blink.

7-34

At flasher light (right)Tester (+) lead Dark green lead Tester (–) lead Black terminal

At flasher light (left)Tester (+) lead Chocolate lead Tester (–) lead Black terminal

13

23

5. Voltage


Turn the main switch to on.Turn the turn switch to left or right.Check for voltage (12V) on the “Chocolate”lead and “Dark green” at the flasher light ter-minal.

MEETSSPECIFICATION



Wiring connection

Wiring circuit from the turn switch to bulbsocket connector is fault. Repair.Refer to “CIRCUIT DIAGRAM”.



CONTINUITY

2. Neutral switch


CONTINUITY

NO CONTINUITY


NO CONTINUITY

Replace the left neutral switch.

SIGNAL SYSTEM ELEC

SR806027

4. If the neutral indicator lights fails to operate.

7-35

Tester (+) lead Black terminal Tester (–) lead Black terminal

1

2

12

COOL DOWN

HEAT UP

A

B

3. Voltage

Connect the pocket tester (DC20V) to thefuel gauge coupler.

Tester (+) lead Brown terminal

Tester (–) lead Sky blue terminal

Turn the main switch to on position.Select the gear position in neutral.Check for voltage (12V) of the “Sky blue”lead on the neutral switch.

MEETSSPECIFICATION



Check the connection of the entire signal sys-tem.Refer to “CIRCUIT DIAGRAM”.

1. Thermo switch

Disconnect the thermo switch connectorfrom the wireharness.

Connect the pocket tester (Ω 1) to thethermo switch lead.

Check the Terminal 1 and 3 for continuity.

MEETSSPECIFICATION


Replace the thermo switch.

SIGNAL SYSTEM ELEC

SR******

5. If the carburetor heater fails to operate.

7-36

SIGNAL SYSTEM ELEC

Tester (+) lead Terminal Tester (–) lead Terminal

12

2. Heater unit resistance

Remove the heater unit from the carburetor.Connect the pocket tester (Ω 1) to theheater unit.

Check the heater unit for specificated resis-tance.

Heater unit resistance:6 10 Ω (20C)

MEETSSPECIFICATION


Check the connections of the entire signalsystem.Refer to “WIRING DIAGRAM”.


Replace the heater unit.

CHAPTER 8.TROUBLE SHOOTING

STARTING FAILURE/HARD STARING 8-1. . . . . . . . . . . . . . . . . . . . . . . . . . .

POOR IDLE SPEED PERFORMANCE 8-2. . . . . . . . . . . . . . . . . . . . . . . . . . .

POOR MEDIUM AND HIGH SPEED PERFORMANCE 8-3. . . . . . . . . . . . .

POOR SPEED PERFORMANCE 8-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CLUTCH SLIPPING/DRAGGING 8-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

FAULTY GEAR SHIFTING 8-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

OVER HEATING OR OVER-COOLING 8-5. . . . . . . . . . . . . . . . . . . . . . . . . . .

FAULTY BRAKE 8-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

FRONT FORK MALFUNCTION 8-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

INSTABLE HANDLING 8-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

STARTER MOTOR DOES NOT OPERATE 8-7. . . . . . . . . . . . . . . . . . . . . . . .

FAULTY SIGNAL AND LIGHTING SYSTEM 8-8. . . . . . . . . . . . . . . . . . . . . .

8-1

STARTING FAILURE/HARD STARTINGTRBLSHTG

NOTE:

EB90000

TROUBLESHOOTING

The following troubleshooting does not cover all the possible causes of trouble. It should be helpful,however, as a guide to troubleshooting. Refer to the relative procedure in this manual for inspection,adjustment and replacement of parts.

SR90000

STARTING FAILURE/HARD STARTINGFUEL SYSTEMFuel tankEmptyClogged fuel tank cap breather holeDeteriorated fuel or fuel containing water orforeign material

Fuel cockClogged fuel hoseClogged fuel cock

CarburetorDeteriorated fuel or fuel containing water orforeign material

Clogged pilot jetClogged air passage Improperly set pilot screwClogged pilot air passage Improperly sealed valve seat Improperly adjusted fuel levelClogged starter jetDamaged carburetor joint Improperly tightened carburetor joint clamphose

Starter plunger malfunctionClogged emulsion (heated water) tubeSucked-in airAir filterClogged air filter element Improper air filter setting

COMPRESSION SYSTEMCylinder and cylinder headLoose spark plugLoose cylinder headBroken cylinder head gasketBroken cylinder gasketWorn, damaged or seized cylinderPiston and piston ringWorn pistonWorn, fatigued or broken piston ringSeized piston ringSeized or damaged piston

Valve system Improperly adjusted valve clearance Improperly sealed valve Improperly contacted valve and valve seat Improper valve timingBroken valve springSeized valve

8-2

POOR IDLE SPEED PERFORMANCETRBLSHTG

IGNITION SYSTEMBattery Improperly charged batteryFaulty batteryFuseBurnt out, improper connectionSpark plug Improper plug gapWorn electrodesWire between terminals broken Improper heat rangeFaulty spark plug capIgnition coilBroken or shorted primary/secondary coilFaulty high tension cordBroken ignition coil body

Ignition systemFaulty C.D.I. unitFaulty pick up coilBroken magneto woodruff keySwitchFaulty main switchFaulty “ENGINE STOP” switchFaulty front and/or rear brake switchFaulty sidestand switchWiringLoose battery terminalLoose coupler connection Improperly groundedBroken wireharness

SR901000

POOR IDLE SPEED PERFORMANCEPOOR IDLE SPEED PERFORMANCECarburetor Improperly returned starter plunger loose or clogged pilot jetDamaged carburetor joint Improperly tightened carburetor joint clamphose

Improperly adjusted idle speed(Pilot screw), (Throttle stop screw)

Improperly adjusted throttle cableFlooded carburetor

Air filterClogged air filter elementIgnition systemFaulty spark plugFaulty high tension cordFaulty C.D.I. unitFaulty pick up coilFaulty ignition coilValve system Improperly adjusted valve clearance

8-3

POOR MEDIUM AND HIGH SPEED PERFORMANCETRBLSHTG

EB902000

POOR MEDIUM AND HIGH SPEED PERFORMANCEPOOR MEDIUM AND HIGH SPEED PERFORMANCERefer to “STARTING FAILURE/HARD STARTING” section. (Fuel system, electrical system, compres-sion system and valve train)Carburetor Improperly adjusted fuel levelClogged main nozzleClogged or loose pilot jet

Air filterClogged air filter element

SR******

POOR SPEED PERFORMANCEPOOR SPEED PERFORMANCEIgnition systemDirty spark plug Improper heat rangeFaulty C.D.I. unitFaulty pick up coilFuel systemClogged fuel tank cap breather holeClogged air cleaner elementClogged jet Improperly adjusted fuel level

Compression systemWorn cylinderWorn or seized piston ringCylinder head gasket brokenCylinder gasket brokenCarbon deposit build-up Improperly adjusted valve clearance Improperly contacted valve and valve seatFaulty valve timingClutchRefer to “CLUTCH SLIPPING/DRAGGING”section

Engine oil Improper oil level (low or over oil level) Improper quality (Low oil viscosity)DeteriorationClogged oil passageBrakesDragging brake

8-4

FAULTY CLUTCH/FAULTY GEAR SHIFTINGTRBLSHTG

EB904000

CLUTCH SLIPPING/DRAGGINGCLUTCH SLIPPINGClutch Improperly adjusted clutch cableLoose clutch springFatigued clutch springWorn friction plate/clutch plate Incorrectly assembled clutchEngine oil Improper oil level Improper quality/(low viscosity)Deterioration

CLUTCH DRAGGINGClutchWarped pressure plateUnevenly tensioned clutch springBent push rodBroken clutch bossBurnt primary driven gear bushingBent clutch plateSwollen friction plateMatch marks not alignedEngine oil Improper oil level Improper quality/(high viscosity)Deterioration

EB903000

FAULTY GEAR SHIFTINGHARD SHIFTINGRefer to “CLUTCH DRAGGING”.SHIFT PEDAL DOES NOT MOVEShift shaft Improperly adjusted shift rodBent shift shaftShift cam, shift forkGroove jammed with impuritiesSeized shift forkBent shift fork guide barTransmissionSeized transmission gearJammed impurities Incorrectly assembled transmissionJUMP-OUT GEARShift shaft Improperly adjusted shift lever position Improperly returned stopper leverShift forkWorn shift forkShift cam Improper thrust playWorn shift cam grooveTransmissionWorn gear dog

8-5

OVER HEATING/FAULTY BRAKETRBLSHTG

SR905000

OVER HEATING OR OVER-COOL-INGOVER HEATINGIgnition system Improper spark plug gap Improper spark plug heat rangeFaulty C.D.I. unitFuel system Improper carburetor setting Improper fuel level adjustmentClogged air filter elementCompression systemHeavy carbon deposit build-up Improperly adjusted valve timing Improperly adjusted valve clearanceEngine oil Incorrect engine oil level Improper engine oil quality (High viscosity)Low engine oil qualityBrakesDragging brake

SR906001

FAULTY BRAKEPOOR BRAKING EFFECTFront brakeWorn brake padWorn brake discAir in brake fluidLeaking brake fluidFaulty master cylinder kitFaulty caliper seal kitLoose union boltBroken brake hoseOily or greasy brake padOily or greasy brake discRear brake Improper brake pedal adjustmentWorn brake shoe Improper brake shoe contactWorn camshaftWorn brake drumMud or water into brake drum insideOily or greasy brake liningFaulty brake cableBroken or fatigued tension springFaulty camshaft, cam lever

8-6

FRONT FORK MALFUNCTION/INSTABLE HANDLINGTRBLSHTG

SR907000

FRONT FORK MALFUNCTIONOIL LEAKAGEBent, damaged or rusty inner tubeDamaged or cracked outer tubeDamaged oil seal lipLoose hexagon boltDamaged cap bolt O-ring Improperly installed oil sealMALFUNCTIONBent inner tubeDeformed outer tubeDamaged fork springBent cylinder complete Improper oil viscosity (High viscosity) Improper oil levelWorn or damaged slide metal

SR908000

INSTABLE HANDLINGINSTABLE HANDLINGHandlebars Improperly installed or bentLoose handlebar tightening boltSteering Improperly installed handlebar crownLoose or overtightening steering nutBent under bracket Improperly installed steering shaft(improperly tightened ring nut)

Damaged bearing or ball raceFront forksUneven oil levels on both sidesUneven spring tensionBroken front fork springFatigued front fork springTwisted front forksWheels Incorrect wheel balanceLoose spooksDeformed wheel rimUnevenly worn tires Incorrect tire pressureLoose bearingBent or loose wheel axleExcessive wheel runoutFrameTwisted Improperly installed bearing raceDamaged head pipe bearingsRear armFaulty bearingsWorm or damagedFaulty bushingBent rear armRear shock absorberFatigued spring Improperly adjusted spring preloadOil leakageDrive chain Improperly adjusted chain line

8-7

STARTER MOTOR DOES NOT OPERATETRBLSHTG

SR******

STARTER MOTOR DOES NOT OPERATESTARTER MOTOR DOES NOT OPERATEBattery Insufficient battery capacityFaulty batteryFuseBurnt out, improper connectionSwitchFaulty main switchFaulty starter switchFaulty clutch switchFaulty neutral switchFaulty sidestand switchFaulty starting circuit cut-off relayFaulty starter relayWireharnessLoose battery terminalLoosely connected coupler Improperly groundedBroken wireharnessStarter motorWorn brushFaulty commutatorBroken armature coilEngineFaulty starter clutchSeized engine

8-8

FAULTY SIGNAL AND LIGHTING SYSTEMTRBLSHTG

YP909000

FAULTY SIGNAL AND LIGHTING SYSTEMHEADLIGHT DARK Improper bulbToo many electric accessoriesHard chargingFaulty rectifier/regulatorFaulty battery Improperly connected coupler, connector,wireharness

Improperly groundedFaulty main switch or Lights (dimmer) switchBulb life expiredBULB BURNT OUT Improper bulbFaulty batteryFaulty rectifier/regulator Improperly grounded Improperly mounting light unitBulb life expiredFLASHER DOES NOT BLINK Improperly grounded Insufficient battery capacityFaulty fuseFaulty turn switchFaulty flasher relayBroken wireharness, incorrect coupler con-nection

Bulb burnt outFLASHER KEEPS ONFaulty flasher relay Insufficient battery capacity(nearly discharged)

Bulb burnt out (front or rear)

FLASHER BLINKS SLOWERFaulty flasher relay Insufficient battery capacity(nearly discharged)

Improper bulbFaulty main and/or turn switchFLASHER BLINKS QUICKER Improper bulbFaulty flasher relayHORN DOES NOT SOUNDFaulty batteryFaulty fuseFaulty main and/or horn switch Improper horn adjustmentFaulty horn (burnt coil, connector)Broken wireharness

COLOR CODEB Black. . . . . Br Brown. . . . Ch Chocolate. . . Dg Dark green. . . G Green. . . . L Blue. . . . . O Orange. . . .

Sb Sky blue. . . . P Pink. . . . . R Red. . . . . Y Yellow. . . . . W White. . . . Br /L Brown/Blue. . Br /W Brown/White.

G/Y Green/Yellow. . L/B Blue/Black. . . L/R Blue/Red. . . L/W Blue/White. . L/Y Blue/Yellow. . . Y/R Yellow/Red. . . R/W Red/White. .

W/L White/Blue. . W/R White/Red. .

1 C.D.I. magneto2 Rectifier /Regulator3 Starter relay4 Battery5 Fuse6 Main switch7 Thermo switch8 Heater unit9 Handlebar switches (right)10 Engine stop switch11 Start switch12 C.D.I. unit13 Ignition coil14 Spark plug15 Clutch switch16 Sidestand switch17 Neutral relay18 Speedometer19 Neutral indicator light20 Turn indicator light (left)21 Turn indicator light (right)22 Hi-beam indicator light23 Meter light24 Neutral switch25 Rear flasher lights26 Tail/Brake light27 Front brake switch28 Rear brake switch29 Front flasher lights30 Auxilialy light31 Flasher relay32 Horn33 Handlebar switches (left)34 Lights switch35 Horn switch36 Dimmer switch37 Turn switch38 Starting motor39 Headlight

SR125 ’97 WIRING DIAGRAM

Documents

Yamaha SR125_Service Manual 3MW-AE1 1997 (English)