hyosung-SF50 Rush

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99000-91310

SERVICE MANUAL

HYOSUNG MOTORS & MACHINERY INC.

CHASSIS

ELECTRICAL SYSTEM

GROUP INDEX

GENERAL INFORMATION 1

PERIODIC MAINTENANCE 2

ENGINE 3

FUEL SYSTEM 4

5

6

SERVICING INFORMATION 7

* This manual has been prepared on the basis of the latest specif ication at the t ime of publica-tion.If modif ication has been made since then, dif-ference may exist between the content of thismanual and the actual vehicle.

* Illustrations in this manual are used to show the basic principles of operation and work proce-dures.They may not represent the actual vehicle exactly in detail.

* Th is manual is in tended for those who have enough know ledge and sk i l l s f o r se rv i c i ng HYOSUNG vehicles. Without such knowledge and skills, you should not attempt servicing by relying on this manual only.Instead, please contact your nearby authorized HYOSUNG motorcycle dealer.

COPYRIGHT HYOSUNG MOTORS & MACHINERY INC. 1999

HYOSUNG MOTORS & MACHINERY INC.

FOREWORD

This manual contains an introductory description on HYOSUNG PRIMA(SF-50) and procedures for its inspec-tion/service and overhaul of its main components.Other information considered as generally known isnot included.Read GENERAL INFORMATION section to familiarizeyourself with out l ine of the vehicle and MAINTE-NANCE and other sect ions to use as a guide forproper inspection and service.This manual will help you know the vehicle better sothat you can assure your customers of your optimum and quick service.

HOW TO USE THIS MANUAL

TO LOCATE WHAT YOU ARELOOKING FOR:1. The text of this manual is divided into sections.2. As the title of these sections are listed on the previous

page as GROUP INDEX, select the section where what you are looking for belong.

3. Holding the manual as shown at the right will allow you to findthe first page of the section easily.

4. On the first page of each section, its contents are listed. Findthe item and page you need.

COMPONENT PARTS

Example: Rear wheel/Rear brake

SYMBOLListed in the table below are the symbols indicating instructions and other information necessary for servicing and meaning associated with them respectively.

Apply THREAD LOCK 1324.

Apply or use brake fluid.

Measure in voltage range.

Measure in resistance range.

Measure in current range.

Use special tool.

Torque control required.Data beside it indicates specified torque.

Apply oil. Use engine oil unless otherwise specified.

Apply SUPER GREASE A.

Apply SILICONE GREASE.

Apply MOLY PASTE.

Apply BOND 1215.

DEFINITIONSYMBOL DEFINITIONSYMBOL

Apply SUPER GREASE C.

GENERAL INFORMATION

INFORMATION LABELS 1-1

GENERAL PRECAUTIONS 1-1

SERIAL NUMBER LOCATION 1-3

FUEL AND OIL RECOMMENDATIONS 1-3

BREAK-IN PROCEDURES 1-4

EXTERIOR ILLUSTRATION 1-5

SPECIFICATIONS 1-6

CONTENTS

1

1-1 GENERAL INFORMATION

Indicates a potential hazard that could result in vehicle damage.

NOTE:Indicates special information to make maintenance easier or instructions cleaner.

Please note, however, that the warning and cautions contained in this manual cannot possibly cover all potential hazards relating to the servicing, or lack of servicing, of the motorcycle. In addition to the WARNING and CAUTION stated, you must use good judgement and basic mechanical safety principles. If you are unsure about how to perform aparticular service operation, ask a more experienced mechanic for advice.

GENERAL PRECAUTIONS

CAUTION

WARNING

WARNING / CAUTION / NOTE

Please read this manual and follow its instructions carefully. To emphasize special information, the symbol and the words WARNING, CAUTION and NOTE have special meanings. Pay special attention to the messages highlighted by these signal words.

Proper service and repair procedures are important for the safety of the service machanic and the safetyand reliability of the vehicle.

When 2 or more persons work together, pay attention to the safety of each other. When it is necessary to run the engine indoors, make sure that exhaust gas is forced outdoors. When working with toxic or flammable materials, make sure that the area you work in is wellventilated

and that you follow all off the material manufacturers instructions. Never use gasoline as a cleaning solvent. To avoid getting burned, do not touch the engine, engine oil or exhaust system during or for a while

after engine operation. After servicing fuel, oil, exhaust or brake systems, check all lines and fittings related to the system for

leaks.

WARNING

Indicates a potential hazard that could result in death or injury.

GENERAL INFORMATION 1-2

If parts replacement is necessary, replace the parts with HYOSUNG Genuine Parts or their equivalent. When removing parts that are to be reused, keep them arranged in an orderly manner so that they may be

reinstalled in the proper order and orientation. Be sure to use special tools when instructed. Make sure that all parts used in reassembly are clean, and also lubricated when specified. When use of a certain type of lubricant, bond, or sealant is specified, be sure to use the specified type. When removing the battery, disconnect the negative cable first and then positive cable. When reconnect-

ing the battery, connect the positive cable first and then negative cable, and replace the terminal cover on thepositive terminal.

When performing service to electrical parts, if the service procedures do not require use of bat-tery power, diconnect the negative cable at the battery.

Tighten cylinder head and case bolts and nuts, beginning with larger diameter and ending with smallerdiameter, from inside to outside diagonally, to the specified tightening torque.

Whenever you remove oil seals, gaskets, packing, O-rings, locking washers, cotter pins, circlips, andcertain other parts as specified, be sure to replace them with new ones. Also, before installing these newparts, be sure to remove any left over material from the mating surfaces.

Never reuse a circlip. When installing a new circlip, take care not to expand the end gap larger thanrequired to slip the circlip over the shaft. After installing a circlip, always ensure that it is completely seat-ed in its groove and securely fitted.

Do not use self-locking nuts a few times over. Use a torque wrench to tighten fasteners to the torque values when specified. Wipe off grease or oil

if a thread is smeared with them. After reassembly, check parts for tightness and operation.

To protect environment, do not unlawfully dispose of used motor oil and other fluids: batteries, and tires. To protect Earths natural resouces, properly dispose of used vehicles and parts.

CAUTION

HYOSUNG PRIMA (SF-50)

SERIAL NUMBER LOCATION

The frame serial number or V.I.N. (Vehicle Identification Number) is stamped on the right side of the frame under thefootboard. The engine serial number is located on the up side of the crankcase assembly.These numbers are required especially for registering the machine and ordering spare parts.

FUEL AND OIL RECOMMENDATION

FUELGasoline used should be graded 85-95 octane (Research Method) or higher. An unleaded gasoline type is recommended.

TRANSMISSION OIL Make sure that the transmission oil you use comes under APIclassificat ion of SH, SG or SF and that i ts v iscosi ty rat ingis SAE 10W/30 or 10W/40. If an SAE 10W/30 or 10W/40 motoroil is not available, select an alternate according to the right chart.

* Difference between photographs and actual motorcycles depends on the markets.

RIGHT SIDE LEFT SIDE



FRONT FORK OILUse fork oil : TELLUS #37

BREAK-IN PROCEDURES

During manufacture only the best possible materials are used and all machined parts are finished to a very high standard but it is still necessary to allow the moving parts to BREAK-INbefore subjecting the engine to maximumstresses. The future performance and reliability of the engine depends on the care and restraint exercised during itsearly life. The general rules are as follows: Keep to these break-in engine speed limits:

Up to 1,000km(600miles): Less than 1/2 throttle. Upon reaching an odometer reading of 1,000 km you can subject the motorcycle to full throttle operation. Do not maintain constant engine speed for an extended period during any portion of the break-in. Try to vary the

throttle position.

Since the brake system of this motorcycle is filled with a glycol-based brake fluid by the manufacturer, do notuse or mix different types of fluid such as silicone-based and petroleum-based fluid for refilling the sys-tem, otherwise serious damage will result.Do not use any brake fluid taken from old or used or unsealed containers.Never re-use brake fluid left over from a previous servicing, which has been stored for a long period.

WARNING

ENGINE OILSpecification and classification: APOLLOIL BIKE-K, HYPOL HS

BRAKE FLUIDSpecification and classification: DOT4


320

635

740

1,11

0

990

125

535 69

0

Head lamp Rear reflector Tail/Brake lamp

(Front) Turnsignal lamp

(Rear) Turnsignal lamp

600 71

0

1,825

135

1,270

350

EXTERIOR ILLUSTRATION

SPECIFICATIONS

DIMENSIONS AND DRY MASSOverall length 1,825 mm (71.9 in) Overall width 635 mm (25.0 in)Overall height 1,110 mm (43.7 in)Wheelbase 1,270 mm (50.0 in)Ground clearance 125 mm (4.9 in)Dry mass 88 kg (194 lbs)

ENGINEType Two-stroke, forced air cooledNumber of cylinder 1Bore 41 mm (1.6 in)Stroke 37.4 mm (1.5 in)Piston displacement 49 (3.0 cu.in)Carburetor SIDE DRAFT VARIABLE VENTURI (PISTON)Air cleaner Wet filter typeStarter system Kick/self starterCorrected compression ratio 7.4 : 1Intake system Reed valve

TRANSMISSIONClutch Dry shoe, automatic, centrifugal typeReduction ratio 2.997~0.813Drive system V-belt drive

CHASSISFront suspension Telescopic typeRear suspension Coil spring typeCaster 25Trail 75mm (2.95in)Steering angle 45(right & left)Front tire size 110/70-12 47JRear tire size 120/70-12 51JFront brake DiscRear brake Drum


ELECTRICALIgnition type CDItypeIgnition timing 20B.T.D.C. at 1,000 rpmSpark plug BR8HSABattery 12V 3Ah/10HRGenerator MagnetoFuse 10AHeadlamp 15W2Turn signal lamp 10W4Tail/Brake lamp 5/10W Speedometer lamp 1.7W2Oil level indicator lamp 1.7WTurn signal indicator lamp 1.7W

CAPACITIESFuel tank 4.8Engine oil tank 1.0Transmission oil 110cc (Replace)

130cc (Overhaul)


NOTE:The specifications are subject to change without notice.

PERIODIC MAINTENANCE SCHEDULE 2- 1

MAINTENANCE PROCEDURES 2- 3

BATTERY 2- 3

CYLINDER HEAD NUTS AND EXHAUST PIPE NUTS 2- 4

CYLINDER HEAD AND CYLINDER 2- 4

SPARK PLUG 2- 4

FUEL LINE 2- 5

AIR CLEANER ELEMENT 2- 5

THROTTLE CABLE PLAY 2- 6

ENGINE IDLE SPEED 2- 7

OIL PUMP 2- 7

TRANSMISSION OIL 2- 8

BRAKES 2- 8

TIRES 2-10

STEERING 2-11

FRONT SUSPENSION 2-11

REAR SUSPENSION 2-12

CHASSIS AND ENGINE MOUNTING BOLTS AND NUTS 2-12

CONTENTS

2

PERIODIC MAINTENANCE

2-1 PERIODIC MAINTENANCE

ItemInitial 1,000 km Every 4,000 km Every 8,000 km page

Interval

Battery

Cylinder head nutsexhaust pipe nuts

Cylinder head, cylinder.

Spark plug

Fuel line

Air cleaner element

Throttle cable play

Engine idle speed

Oil pump

Transmission oil

Inspect

Inspect

Clean

Inspect

Inspect

Inspect

Inspect

Inspect

Inspect

Inspect

Clean

Inspect

Inspect

Inspect

Inspect

Clean

Replace

Inspect

2-3

2-4

2-4

2-4

2-5

2-5

2-6

2-7

2-7

2-8

Clean every 3,000 km

Replace every 4 years

ItemInitial 1,000 km Every 4,000 km Every 8,000 km page

Interval

Brakes

Brake hose

Brake fluid

Tires

Steering

Front suspension

Rear suspension

Chassis bolts and nuts

Inspect

Inspect

Inspect

Inspect

Inspect

Inspect

Inspect

Inspect

Inspect

Inspect

Inspect

Inspect

Inspect

Inspect

Inspect

Inspect



CHASSIS

2-9

2-9

2-9

2-10

2-11

2-11

2-12

2-12

PERIODIC MAINTENANCE SCHEDULE

The chart below lists the recommended intervals for all the required periodic service work necessary to keep the motorcycle operating at peak performance and economy.

NOTE:More frequent servicing should be performed on motorcycles that are used under severe conditions.

PERIODIC MAINTENANCE CHARTENGINE

PERIODIC MAINTENANCE 2-2

LUBRICATION CHARTThe maintenance schedule, which follows, is based on this philosophy. It is timed by odometer indication, and is calculated to achieve the ultimate goal of motorcycle maintenance in the most economical manner.

Be careful not to apply too much grease into the brake cam. If grease is on the linings, brake slippage willresult.

WARNING

Lubricate exposed parts which are subject to rust, with either motor oil or grease whenever the motorcycle hasbeen operated under wet or rainy conditions.Before lubricating each part, clean off rusty sports and wipe off grease, oil, dirt or grime.

ItemInitial and Every 4,000 km Every 8,000 km

Interval

Throttle cable

Throttle grip

Brake cable

Speedometer cable

Speedometer gear box

Brake cam

Steering stem bearing

Motor oil

Motor oil

Grease

Grease

Grease

Grease

Grease every 2 years or 20,000 km

2-3 MAINTENANCE PROCEDURE

Remove the pillion seat for measure of battery voltage. Remove the battery lead and then lead at the

battery terminls and remove the battery. Using pocket tester, measure the battery voltage.If the tester reading is less than 12.0V, rechargethe battery with a battery charger. (Refer to page 5-13)

W h e n r e c h a r g i n g t h e b a t t e r y r e m o v ethe battery from motorcycle.O t h e r w i s e , r e g u l a t o r / r e c t i f i e r u n i tshould be an obstacle.

W h e n r e c h a r g i n g t h e b a t t e r y , d o n o tremove the caps.

When recharging the battery, above thecharge electr ic current and t ime shouldbe kept as 12V.

CAUTION

NOTE:Inspect Initial 1,000 km and Every 4,000 km.

Recharge

Standard charge

Fast charge

0.4A5~10 Hours

4A30 Minutes

MAINTENANCE PROCEDURE

This section describes the service procedures for each section of the periodic maintenance.

BATTERY

Pocket tester : 09900-25002

Minimum 12.0VBettery voltage

MAINTENANCE PROCEDURE 2-4

Cylinder head nut : 8~12 Nm (0.8~1.2 kgm)

Carbon

CYLINDER HEAD NUTS AND EXHAUSTPIPE NUTS

CYLINDER HEAD NUTS Remove the personal trunk. Remove the spark plug cap. Remove the cylinder head cover bolt.

(Refer to page 3-5) Tighten the four nuts to the specified torque with a

torque wrench, when engine is cold.


Carbon deposits in the combustion chamber and thecylinder head will raise the compression ratio and maycause preignition or overheating. Carbon deposited atthe exhaust port of the cylinder will prevent the flow ofexhaust gases, reducing the output. Remove carbondeposits periodically.

CYLINDER HEAD AND CYLINDER

Exhaust pipe nuts : 8~12 Nm (0.8~1.2 kgm)

EXHAUST PIPE NUTS Tighten the exhaust pipe nuts to the specified

torque.

NOTE:Remove carbon Every 8,000km.

NOTE:Inspect Initial 1,000km and Every 4,000km,Replace every 8,000km.

Neglecting the spark pulg maintenance eventually leads todifficult starting and poor performance. If the spark plug isused for a long period, the electrode gradually burns awayand carbon builds up along the inside part. In accordancewith the Periodic Inspection Chart, the plug should beremoved for inspection, cleaning and to reset the gap. Carbon deposits on the spark plug will prevent good

sparking and cause misfiring. Clean the deposits offperiodically.

SPARK PLUG


If the center electrode is fairly worn down, the plugshould be replaced and the plug gap set to the speci-fied gap using a thickness gauge.

Thickness gauge : 09900-20804

0.6 ~ 0.7 mmSpark plug gap

BR8HSA

TYPE

Standard

SPARK PLUG SPECIFICATION

Tighten the spark plug to the specification.

FUEL LINE

NOTE:Inspect Initial 1,000 km and Every 4,000 km,Replace every four years.

NOTE:Clean Every 3,000km and Replace Every 12,000km.

Spark plug : 25~30 Nm (2.5~3.0 kgm)

To check the spark plug, first make sure thatthe fuel used is unleaded gasoline, and if plugis either sooty with carbon or burnt white,replace it.

Confirm the thread size and reach when replac-ing the plug.

CAUTION

If the air cleaner is clogged with dust, intake resistancewill be increased with a resultant decrease in power out-put and an increase in fuel consumption. Check andclean the element in the following manner. Remove the air cleaner cover by removing the eight

screw.

AIR CLEANER ELEMENT

Check the spark plug for burnt condition. If abnormal,replace the plug as indicated in the chart.

Inspect leakage of the fuel line and connection part.If abnormal, replace it.


Inside

Remove the air cleaner cover, separate the element.

Fill a washing pan of a proper size with non-flammablecleaning solvent. Immerse the element in the cleaningsolvent and wash them clean.

Squeeze the cleaning solvent out of the washed ele-ment by pressing it between the palms of both hands:do not twist or wiring the element or if will developtears.

Immerse the element in Hyosung genuine oil, andsqueeze the oil out of the element leaving it slightlywet with oil.

Fit the elements to the cleaner case properly.

Before and during the cleaning operation,inspect the element for tears. A torn elementmust be replaced.

Be sure to position the element snugly and cor-rectly, so that no incoming air will bypass it.Remember, rapid wear of piston rings andcylinder bore is often caused by a defective orpoorly fitted element.

CAUTION

Loosen the lock nut and adjust the cable play by turning adjuster in or out to obtain the followingcable play. After adjusting play, tighten the lock nut.

THROTTLE CABLE PLAY


0.5 ~ 1.0 mmThrottle cable play

Non-flammablecleaning solvent

Hyosung genuine oil


Fixing

ENGINE IDLE SPEED



start up the engine and set its speed at anywherebetween 1,750 and 1,850 rpm by turning the throttlestop screw .

Make this adjustment when the engine is hot.

CAUTION

1,800 50 rpmEngine idle speed

Engine tachometer : 09900-26006

The engine oil is fed by the oil pump to the engine. Theamount of oil fed to it is regulated by engine speed andoil pump control lever which is controlled by amount ofthrottle opening.Check the oil pump in the following manner to confirmcorrect operation for throttle valve full closing position. Fix the throttle grip. (The early idling condition) Check whether the mark on the oil pump control

lever is aligned with the index mark when thethrottle grip is fixed as above.

If the marks are not aligned, loosen lock nuts andturn the adjuster in or out to align the marks.

After aligning the marks, tighten the lock nuts .

OIL PUMP

Oil pump cable adjustment must be done afterthrottle cable adjustment.

CAUTION


Middle line

Oil drain plug


Inspect transmission oil periodically following procedurebelow. Remove the low leg shield. Remove the clutch cover.(Refer to page 3-6)

Remove the oil level bolt and inspect oil level.If the level is below the level hole, add oil until oilflows from the level hole.

Tighten the oil level bolt to the specified torque.

TRANSMISSION OIL

BRAKES

Oil level bolt : 9~15 Nm (0.9~1.5 kgm)

FRONT BRAKE FLUID LEVEL Keep the motorcycle upright and place the handlebar

straight. Check brake fluid level by observing the middle line

on the brake fluid reservoir. When the level is bolow the middle line, replenish

with brake fluid that meets the following specification.

DOT4Specification and classification

The brake system of this motorcycle is filled witha glycolbased brake fluid. Do not use or mix dif-ferent type of fluid such as silicone-based andpetroleum-based. Do not use any brake fluidtaken from old, used or unsealed containners.Never re-use the brake fluid left over from the lastservicing and stored for long periods.

WARNINGBrake fluid, if it leaks, will interfere with safe run-ning and immediately discolor painted surfaces.Check the brake hoses for cracks and hose jointsfor leakage before riding.

WARNINGHYOSUNG Brake fluid : 99000-23021

NOTE:Inspect Initial 1,000 km and Every 4,000 km.Replace the hose Every four years.Replace the brake fluid Every two years.


Do original position

TurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurningTurning

BRAKE PADSWearing condition of brake pads can be checked byobserving the limit line marked on the pad. When thewear exceeds the limit mark, replace the pads with newones.

BRAKE LAMP SWITCHFor the brake lamp come on after the brake lever ispulled, adjust the brake lamp switch.

Bleed air from the bleeder valve. Squeeze and release the brake lever several times in

rapid succession, and squeeze the lever fully withoutreleasing it. Loosen the bleeder valve by turning it aquarter of a turn so that the brake fluid runs into thereceptacle: this will remove the tension of the brakelever causing it to touch the handlebar grip. Then,close the valve, pump and squeeze the lever, andopen the valve. Repeat this process until the fluidflowing into the receptacle no longer contains air bub-bles.

Close the bleeder valve, and disconnect the pipe. Fillthe reservoir to the upper end of the inspection win-dow.

Bleeder valve : 6~9 Nm (0.6~0.9 kgm)

Replenish the brake fluid reservoir as necessarywhile bleeding the brake system.Make sure that there is always some fluid visiblein the reservoir.

CAUTION

BLEEDING AIR FROM THE BRAKE FLUID CIRCUITAir trapped in the fluid circuit acts like a cushion toabsorb a large proportion of the pressure developed bythe master cylinder and thus interferes with the full brak-ing performance of the brake caliper. The presence ofair is indicated by sponginessof the brake lever andalso by lack of braking force. Considering the danger towhich such trapped air exposes the machine and rider,it is essential that, after remounting the brake andrestoring the brake system to the normal condition, thebrake fluid circuit be purged of air in the following man-ner: Fill up the master cylinder reservoir to the upper end

of the inspection window. Replace the reservoir capto prevent entry of dirt.

Attach a pipe to the caliper bleeder valve, and insertthe free end of the pipe into a receptacle.


Brake lining wear limit

The extension line of the index mark is within the range.

The extension line of the index mark is outside of the range.

Index mark

Brake lining wear limit

Index mark

15~2

5 m

m

Play is had much

Range

Pin

Front

Front

Handle the brake fluid with care: the fluid reactschemically with paint, plastics, rubber materials, etc.

WARNING

REAR BRAKEAdjust by turning the adjusting nut so that the play is 15~25 mm as shown in the illustration.

Brake lining wear limitThis motorcycle is equipped with the brake lining wearlimit indicator on the rear brake. As shown in the illustra-tion at right, at the condition of normal lining wear, anextended line from the index mark on the brakecamshaft should be within the range embossed on thecrankcase LH. To check wear of the brake lining, followthe steps below. First check if the brake system is properly adjusted. While operating the brake, check to see that the

extension line from the index mark is within the rangeon the brake panel.

If the index mark is outside the range as shown in theillustration at right, the brake shoe assembly shouldbe replaced to ensure safe operation.


TIRES

TIRE PRESSUREIf the tire pressure is too high, the motorcycle will tend toride stiffly and have poor traction. Conversely, if the tirepressure is too low, stability will be adversely affected.Therefore, maintain the correct tire pressure for goodroadability and to prolong tire life.

Play is had littleAdjuster nut


OVER NORMAL SHORT

The standard tire fitted on this motorcycle is110/70-12 47J for front and 120/70-12 51J for rear.The use of a tire other than the standard maycause handling instability. It is highly recom-mended to use a HYOSUNG Genuine Tire.

CAUTION

123

196

172

221

1.75

2.25

1.25

2.00

COLD INFLATIONTIRE PRESSURE

FRONT

REAR

SOLO RIDING

kpa kg/ kpa kg/

DUAL RIDING

NORMAL RIDING

TIRE TREAD CONDITIONOperating the motorcycle with the excessively worn tireswill decrease riding stability and consequently invite adangerous situation. It is highly recommended toreplace the tire when the remaining depth of tire treadreaches the following specification.

Steering should be adjusted properly for smooth turningof handlebars and safe running. Too stiff steering pre-vents smooth turning of handlebars and too loose steer-ing will cause poor stability.Check that there is no play in the front fork assembly bysupporting the machine so that the front wheel is off theground, with wheel straight ahead, grasp lower shockabsorber near the axle and pull forward. If play isfound, perform steering bearing adjustment.(Refer topage 6-21)



STEERING

1.6 mm

1.6 mm

FRONT

REAR

TREAD DEPTH SERVICE LIMIT

Inspect the front shock absorber for oil leakage or otherdamage, and replace the defective parts, if necessary.

FRONT SUSPENSION




Inspect the rear shock absorber for oil leak and themounting rubbers including engine mountings for wearand damage. Replace the defective part if necessary.

REAR SUSPENSION

These bolts and nuts listed below are important safety parts. They must be loosened first and retightened, to the specifiedtorque with a torque wrench.

CHASSIS AND ENGINE MOUNTING BOLTS AND NUTS

Front axle nut() : 33~52 Nm (3.3~5.2 kgm)Steering stem lock nut () : 60~100 Nm (6.0~10.0 kgm)Handlebar clamp nut() : 48~52 Nm (4.8~5.2 kgm)Handlebar set bolt() : 22~28 Nm (2.2~2.8 kgm)Front brake master cylinder bolt() : 8~12 Nm (0.8~1.2 kgm)Front brake hose union bolt() : 20~25 Nm (2.0~2.5 kgm)Front brake caliper mounting bolt() : 18~28 Nm (1.8~2.8 kgm)Front brake air bleeder valve() : 6~9 Nm (0.6~0.9 kgm)Rear axle nut() : 60~90 Nm (6.0~9.0 kgm)Rear shock absorber bolt(upper and lower)() : 22~35 Nm (2.2~3.5 kgm)Rear brake cam lever nut() : 6~9 Nm (0.6~0.9 kgm)Engine mounting bracket bolt() : 48~72 Nm (4.8~7.2 kgm)Engine mounting bolt() : 40~60 Nm (4.0~6.0 kgm)

ENGINE REMOVAL AND REMOUNTING 3- 1

ENGINE REMOVAL 3- 1

ENGINE REMOUNTING 3- 3

ENGINE DISASSEMBLY 3- 4

ENGINE COMPONENTS INSPECTION AND SERVICING 3-14

BEARINGS 3-14

OIL SEALS 3-14

CRANKSHAFT 3-15

AUTOMATIC CLUTCH INSPECTION 3-15

CYLINDER HEAD 3-18

CYLINDER 3-19

PISTON 3-19

REED VALVE 3-22

ENGINE REASSEMBLY 3-22

OIL SEALS 3-22

BEARINGS 3-23

BUSHINGS 3-23

CRANKSHAFT 3-24

CRANKCASE 3-25

CENTER STAND 3-26

REAR AXLE SHAFT, BRAKE AND WHEEL 3-27

TRANSMISSION 3-29

STARTER DRIVEN GEAR AND STARTING MOTOR 3-31

MOVABLE DRIVEN AND CLUTCH 3-32

MOVABLE DRIVE 3-36

KICK STARTER 3-38

PISTON 3-40

OIL PUMP AND INTAKE PIPE 3-42

MAGNETO 3-43

MUFFLER 3-45

ENGINE

3

CONTENTS

3-1 ENGINE

ENGINE REMOVAL AND REMOUNTING

ENGINE REMOVALBefore taking the engine out of the frame, thoroughlyclean the engine with a suitable cleaner. The procedureof engine removal is sequentially explained as follows. Remove the low leg shield. Remove the air cleaner by removing the mounting

bolts and clamp screw .

Disconnect the ignition coil lead wires and spark plugcap.

Disconnect the oil pump cable and the thermoele-ment lead coupler .

Disconnect the throttle cable. (Refer to page 4-2)

Disconnect the vacuum hose , fuel hose and oilhose .

ENGINE 3-2

Disconnect the magneto lead wire and startingmoter lead wire .

Remove the rear brake cable by removing the bolt, bolt and adjuster nut .

Remove the rear shock absorber mounting lowerbolt.

3-3 ENGINE

Remove the engine mounting shaft and remove theengine from the frame.

ENGINE REMOUNTINGThe engine can be mounted in the reverse order ofremoval. Install the damper to the crankcase bracket as shown

in the illustration. With UPmark faced upward, install the crankcase

bracket on the frame. Do not tighten the bracketbolt at this stage. Pull up on the rear part ofcrankcase bracket and while holding it, tighten thebracket bolt to specification. Tighten both the rearshock absorber bolt and engine mounting bolt to specification.

Front side

mark

Damper

UP

10mm

8mm

Engine mounting bracket bolt: 48~72 Nm (4.8~7.2 kgm)

Engine mounting bolt: 40~60 Nm (4.0~6.0 kgm)

Rear shock absorber bolt: 22~35 Nm (2.2~3.5 kgm)

ENGINE 3-4

Install the magneto lead wire and starting motorlead wire correctly.

After remounting the engine, route the wiring harnessproperly and following adjustments are necessary.

PageThrottle cable play 2-6Idling adjustment 2-7Oil pump cable paly 2-7Rear brake cable adjustment 2-10Air bleeding at oil pump 4-9

ENGINE DISASSEMBLY

MUFFLER Remove the muffler by removing the nuts.

MAGNETO Remove the cooling fan. Remove the magneto rotor nut with the special

tool.

Rotor holder : 09930-40113

3-5 ENGINE

Remove the magneto rotor with the special tool.

Remove the magneto stator and key.

Rotor remover : 09930-30163Rotor remover sliding shaft : 09930-30102

REED VALVE Remove the intake pipe with reed valve .

OIL PUMP Remove the oil pump . Remove the oil pump driven gear .

CYLINDER Remove the cylinder cowling. Remove the cylinder head and cylinder .

ENGINE 3-6

Remove the kick starter shaft spring and kickstarter shaft .

KICK STARTER Remove the kick starter lever . Remove the clutch cover .

PISTON Place a cloth beneath the piston and remove the pis-

ton circlip with a long nose pliers. Remove the piston pin and piston . Remove the piston pin bearing .

KICK STARTER DRIVEN GEAR Remove the E-ring with the long nose plier. Remove the spacer , spring and kick starter

driven gear .

3-7 ENGINE

MOVABLE DRIVE FACE Remove the kick starter driven nut with the special

tool.

Remove the fixed drive face and V-belt . Disassemble the movable drive face .

STARTER DRIVEN GEAR Remove the starter driven gear .

MOVABLE DRIVEN FACE Remove the clutch housing with the special tool.

This nut has left-hand thread.

CAUTION

Conrod holder : 09910-20115


ENGINE 3-8

Using a thin blade screwdriver or the like, pry up themovable driven face spring guide .

Remove the pins , movable driven face andfixed driven face .

Loosen the clutch shoe nut with the special tool.


Gradually back off the clutch shoe assemblypressed down by hand to counter the clutchspring load. Releasing the hand suddenly maycause the parts to fly apart.

WARNING

Remove the nut while holding down the clutch shoeassembly by both hands as shown in the illustration.

Remove the nut . Remove the clutch shoe assembly . Remove the spring .

Do not attempt to diassemble the clutch shoeassembly.It is not serviceable.

CAUTION

3-9 ENGINE

Remove the roller bearing with the special tools.

TRANSMISSION Drain transmission oil. Remove the gear box cover . Remove the driveshaft .

Remove the circlip .

Remove the bearing with the special tool.

Bearing remover( 17 mm) : 09923-73210Rotor remover sliding shaft : 09930-30102

Wheel bearing remover : 09941-50111

The removed bearing should be replaced with anew one.

CAUTION


CAUTION

ENGINE 3-10

Remove the oil seal from the gear box cover withthe special tool.


Oil seal remover : 09913-50121

Bearing installer : 09913-76010

Rotor remover sliding shaft : 09930-30102Bearing remover ( 12 mm) : 09921-20210

The removed oil seal should be replaced with anew one.

CAUTION


CAUTION

Remove the circlip and final driven gear . Remove the idle shaft .

Remove the drive shaft bearing .

3-11 ENGINE

WHEEL, BRAKE Remove the rear axle nut and washer . Remove the rear wheel .

Remove the brake shoes and rear axle shaft .

Remove the bearing retainer .



ENGINE 3-12

Remove the oil seal with the special tool.

Remove the cotter pin , washer and shaft . Remove the center stand .

CENTER STAND Remove the return spring .


Crankcase separater : 09920-13120

Loosen the crankcase screws diagonally.

CAUTION

CRANKCASE Remove the crankcase securing screws.

3-13 ENGINE

Remove the crankshaft with the special tool.

Crankcase separater : 09920-13120

Remove the bearings, oil seals and bushings.

ENGINE 3-14

Front side Rear side

Bushing

Bushing

Bushing

Crankcase Crankcase

Using two steel tubes of appropriate size, press outthe engine mounting bushings on a vise as shown inthe illustration.

OIL SEALDamage to the lip of the oil seal may result in leakage ofthe fuel-air mixture or oil. Inspect for damage and besure to replace the damaged seal if found.

BEARINGSWash the bearing with cleaning solvent and lubricatewith motor oil before inspecting.Turn the inner ring and check to see that the inner ringturns smoothly. If it does not turn lightly, quietly andsmoothly, or if noise is heard, the bearing is defectiveand must be replaced with a new one.

ENGINE COMPONENTS INSPECTION AND SERVICING

3-15 ENGINE

WEAR AND CLEARANCE OF CONROD BIG ENDTurn the crankshaft with the conrod to feel the smooth-ness of rotary motion in the big end. Move the rod upand down while holding the crankshaft rigidly to be surethat there is no rattle in the big end.Wear on the big end of the conrod can be estimated bychecking the movement of the small end of the rod. Thismethod can also check the extent of wear on the partsof the conrods big end.If wear exceeds the limit, conrod, crank pin and crankpin bearing should all be replaced.

Excessive crankshaft runout is often responsible forabnormal engine vibration. Such vibration shortensengine life.

CRANKSHAFTCRANKSHAFT RUNOUTSupport crankshaft by Vblocks, with the dial gaugerigged to read the runout as shown.

Service limit 0.08 mmCrankshaft runout

Service limit 3.0 mmConrod big end runout

Service limit 14.047 mmConrod small end bore I.D.

V-block(100 mm) : 09900-21304Magnetic stand : 09900-20701Dial gauge(1/100 mm) : 09900-20606

CONROD SMALL END BORE I.D.Measure the conrod small end diameter with a calipergauge.

AUTOMATIC CLUTCH INSPECTIONThis motorcycle is equipped with an automatic clutchand variable ratio belt drive transmission. The engage-ment of the clutch is governed by engine RPMs andcentrifugal mechanism located in the clutch.To insure proper performance and longevity of theclutch assembly it is essential that the clutch engagessmoothly and gradually. Two inspection checks must beperformed to thoroughly check the operation of the driv-etrain. Follow the procedures listed.

Dial calipers : 09900-20605

ENGINE 3-16

1. CLUTCH-IN INSPECTIONWarm up the motorcycle to normal operating tempera-ture.Remove the right frame side cover.Connect an engine tachometer to the engine.Seated on the motorcycle with the motorcycle on levelground, increase the engine RPMs slowly and note theRPM at which the motorcycle begins to move forward.

Engine tachometer : 09900-26006

Clutch-in RPMStandard

Tolerance

3,600 rpm

200 rpm

Clutch tight RPMStandard

Tolerance

6,000 rpm

200 rpm

2. CLUTCH TIGHT INSPECTIONGrip the front and rear brake lever fully, and measurethe engine RPM when open the throttle.Warm the engine to normal operating temperatures.Connect an engine tachometer to the engine.Apply the rear brake as firm as possible.Briefly open the throttle fully and note the maximumengine RPMs sustained during the test cycle.

Do not apply full power for more than 3 secondsor damage to the clutch or engine may occur.

CAUTION

Service limit 2.0 mmClutch shoe thickness

If the engine RPM does not coincide with the specifiedRPM range, then disassemble the clutch.Clutch shoe - inspect the shoes visually for chips, crack-ing, uneven wear and burning, and check the thickness ofthe shoes with the vernier calipers. If the thickness is lessthan the following service limit, replace them as a set.Clutch springs - visually inspect the clutch springs forstretched coils or broken coils.

3-17 ENGINE

Clutch housing inspect visually the condition of theinner clutch housing surface for scrolling, cracks, oruneven wear. Measure inside diameter of the clutchwheel with inside calipers. Measure the diameter at sev-eral points to check for an in-of-round condition as wellas wear.

DRIVE V-BELTRemove the drive V-belt and check for cracks, wear andseparation. Measure the drive V-belt width with a verniercalipers. Replace it if the drive V-belt width is less thanthe service limit or any defect has been found.

DRIVE FACEInspect the V-belt contact surface of the drive faces forwear, scratches or any abnormality. If there is some-thing unusual, replace the drive face with a new one.

Clutch shoes or springs must be changed as aset and never individually.

CAUTION

Always keep the drive belt away from any greasymater.

CAUTION

Service limit 110.35 mmClutch housing I.D.

Service limit 15.3 mmDrive V-belt width

ROLLER AND MOVABLE DRIVE SURFACEInspect each roller and movable drive surface for wearor damage.

ENGINE 3-18

MOVABLE DRIVEN FACE PIN AND OIL SEALTurn the movable driven faces and check to see that themovable driven faces turn smoothly.If not rotate smoothly, visually inspect the lip of oil seal,movable driven face sliding surface and sliding pins forwear or damage.

MOVABLE DRIVEN SPRINGMeasure the free length of the movable driven spring. Ifthe length is shorter than the service limit, replace thespring with a new one.

Service limit 135~153 mmMovable driven spring free length

MOVABLE DRIVEN FACEInspect the V-belt contacting surface of both drivenfaces for any scratches, wear and damage.Replace the movable driven face with new one if thereare any abnormality.

CYLINDER HEADDecarbon the combustion chamber.Check the gasketed surface of the cylinder head for dis-tortion with a straightedge and thickness gauge, taking aclearance reading at several places.


Service limit 0.1 mmCylinder head distortion

3-19 ENGINE

If the largest reading at any portion of the straightedgeexceeds the limit, rework the surface by rubbing itagainst emery paper (of about # 400) laid flat on the sur-face plate in a lapping manner. The gasketed surfacemust be smooth and perfectly flat in order to secure atight joint: a leaky joint can be the cause of reducedpower output and increased fuel consumption.

CYLINDERDecarbon exhaust port and upper part of the cylinder,taking care not to damage the cylinder wall surface.

The wear of the cylinder wall is determined from diame-ter reading taken at 20 mm from the top of the cylinderwith a cylinder gauge. If the wear thus determinedexceeds the limit indicated below, rework the bore to thenext oversize by using a boring machine or replace thecylinder with a new one.

After reworking the bore to an oversize, be sure tochamfer the edges of ports and smooth the chamferededges with emery paper. To chamfer, use a scraper,taking care not to nick the wall surface.

PISTONCYLINDER TO PISTON CLEARANCECylinder-to-piston clearance is the difference betweenpiston diameter and cylinder bore diameter. Be sure totake the maked diameter at right angles to the pistonpin. The value of elevation is prescribed to be 15 mmfrom the skirt end.

Cylinder gauge set : 09900-20508

Service limit 41.070 mmCylinder bore

Micrometer(25~50 mm) : 09900-20202

Service limit 40.885 mmPiston diameter

ENGINE 3-20

DE-CARBONINGDe-carbon the piston and piston ring grooves, as illus-trated. After cleaning the grooves, fit the rings and rotatethem in their respective grooves to be sure that theymove smoothly.Carbon in groove is liable to cause the piston ring to getstuck in the groove, and this condition will lead toreduced engine power output.A piston whose sliding surface is badly grooved orscuffed due to overheating must be replaced. Shallowgrooves or minor scuff can be removed by grinding withemery paper of about # 400.

PISTON PIN BORE I.D.Using a caliper gauge, measure the piston pin boreinside diameter. If reading exceeds the following servicelimit, replace it with a new one.

Cylinder bore

Piston diameter

Cylinder to piston clearance

Standard

41.005~41.020 mm

40.935~40.950 mm

0.065~0.075 mm

Serivice limit

41.070 mm

40.885 mm

0.120 mm

As a result of the above measurement, if the piston-to-cylinder clearance exceeds the following limit, overhaulthe cylinder and use an oversize piston, or replace bothcylinder and piston. The measurement for the borediameter should be taken in the intake-to-exhaust portdirection and at 20mm from the cylinder top surface.

Dial calipers : 09900-20605

Service limit 10.030 mmPiston pin bore I.D.

3-21 ENGINE

PISTON PIN O.D.Using a micrometer, measure the piston outside diame-ter at three positions.

Micrometer(0~25 mm) : 09900-20201


Service limit 9.980 mmPiston pin O.D.

Fix the piston ring in the piston ring groove, measure thering side clearance with the thickness gauge whilematching the sliding surfaces of piston and ring.

As the piston ring wears, its end gap increases reducingengine power output because of the resultant blow bythrough the enlarged gap. Here lies the importance ofusing piston rings with end gaps within the limit.Measure the piston ring free end gap to check thespring tension.

PISTON RINGSCheck each ring for end gap, reading the gap with athickness gauge shown in the illustration. If the end gapis found to exceed the limit, indicated below, replace itwith a new one.The end gap of each ring is to be measured with thering fitted squarely into the cylinder bore and held at theleast worn part near the cylinder bottom, as shown inthe illustration.

Service Limit 0.75 mm

Piston ring clearance(Assembly condition)

Service limit

3.2 mm

3.1 mm

Piston ring clearance(Free condition)

1st

2nd

Standard

0.02~0.06 mm

0.02~0.06 mm

Piston ring-ring groove clearance

1st

2nd

ENGINE 3-22

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REED VALVEWhen reinstalling the reed valve and stopper plate tothe body, align the both cut on the reed valve and stop-per plate.Apply THREAD LOCK 1324to the stopper platesecuring screws.

Thread Lock 1324

Thread Lock 1324

Super Grease A

When fitting the oil seal in the crankcase, insert itslowly with the special tools.

NOTE:Align the oil seal with edge of the crankcase asshown in the illustration.

Be sure to apply THREAD LOCK 1324to outersurfaces of right and left crankshaft oil seals to pre-vent them from moving.

OIL SEALSFit the oil seals to the crankcase following the procedurebelow.Replace removed oil seals with new ones. Coat SUPER GREASE Ato the lip of the oil seals.

ENGINE REASSEMBLY

Reassembly is generally performed in the reverse orderof disassembly, but there are a number of reassemblingsteps that demand or deserve detailed explanation oremphasis. These steps will be taken up for respectiveparts and components.

Oil seal installer : 09913-75830Bearing installer attachment : 09924-74510Bearing installer pilot : 09924-74540

3-23 ENGINE

BEARINGSInstall new bearings with the special tool.

Bearing installer : 09913-75810Bearing installer : 09913-76010

BUSHINGSUsing two steel tubes of appropriate size and a vise,press the mounting bushings and into thecrankcase holes as shown in the illustration.

NOTE:Knurled end should face inside. Protrusion and should be in the same dimension.

ENGINE 3-24

Crank shaft Crankcase RH Oil seal Oil seal Oil pump drive gear Oil pump driven gear Oil seal

Bushing

Crankcase

Crankcase

Bushing

CRANKSHAFT

Measure the length between the webs referring to thefigure at right when rebuilding the crankshaft.

Standard 35.00.1 mmWidth between webs

3-25 ENGINE

When mounting the crankshaft into the crankcase, itis necessary to pull its left end into the crankcasewith the special tool.

Crankshaft installer : 09910-32812Conrod holder : 09910-20116

Never fit the crankshaft into the crankcase bydriving it with a plastic hammer. Always use thespecial tool, otherwise crankshaft alignmentaccuracy will be affected.

CAUTION

CRANKCASE Wipe the crankcase mating surfaces(both

surfaces)with cleaning solvent. Apply BOND 1215uniformly to the mating surface

of the left half of the crankcase, and install the dowelpins.

Install the two dowel pins. Tighten the crankcase screws securely. Check if the crankshaft rotates smoothly.

Install the new oil seal to the crankcase with thespecial tool.

NOTE:Align the oil seal with edge of the crankcase asshown in the illustration.

BOND 1215


ENGINE 3-26

Hook the center stand spring into the crankcase.

CENTER STAND Install the center stand . Install the shaft , washer and cotter pin .

3-27 ENGINE

Brakecam

REAR AXLE SHAFT, BRAKE AND WHEEL

Install the rear axle shaft into the crankcase bytapping its end lightly.

Apply engine oil on the left end of the rear axle shaftbeing inserted later in the reduction rear box cover.

Apply SUPER GREASE Alightly on the rear brakecam pivot part and install it to the crankcase.

Turn to position the cam where the punched mark on the end face is directed toward the axis of the rearaxle shaft.

Super Grease A

ENGINE 3-28

Slit

Punch mark

When installing the cam lever to the cam, align thepunched mark with the slit of cam lever.

Tighten the cam lever nut to the specified torque.

Install the brake shoes. Apply SUPER GREASE Ato the brake cam and

pin before installing the brake shoes.

Install the rear wheel and nut.

Rear brake cam lever nut : 6~9 Nm (0.6~0.9 kgm)

Rear axle nut : 60~90 Nm (6.0~9.0 kgm)

Super Grease A

Be careful not to apply too much grease to thebrake cam and pin. If grease gets on the lining,brake effectiveness will be lost.

CAUTION

3-29 ENGINE

Thrust

Rounded coner

Circlip

Center

TRANSMISSION

Install the circlip on to the rear axle shaft . Assemble the idle shaft subassembly using the idle

shaft and thrust washer , then install the sub-assembly on the gear box.

Install the final driven gear on the rear axle shaftusing the circlip .

ENGINE 3-30

Oil seal

Align face

Install the washer, new gasket and dowel pin . Install the driveshaft to the gear box cover.

Install the new bearing , to the gear box cover with the special tool.

Apply SUPER GREASE Ato the lip of the oil seal and install it to the gear box cover with the specialtool.



Super Grease A

3-31 ENGINE

Apply BOND 1215at the hatched area shown inthe illustration and install the gear box cover onthe crankcase.

Tighten all the screws evenly one by one in a diago-nal fashion.

BOND 1215

Install the starter driven gear over the leftcrankshaft end.

NOTE:The convex side of hub should face outside wheninstalled in proper position.

STARTER DRIVEN GEAR AND STARTING MOTOR

ENGINE 3-32

Install the starting motor .

MOVABLE DRIVEN AND CLUTCH

3-33 ENGINE

Thrust

Rounded coner

Oil seal

Install the bearing in the fixed driven face withthe special tool.

Install the circlip .




Take care that hit inner race of the bearing.(Fall to ring in the bearing a case.)

CAUTION

Instert surely in the circlip groove.

CAUTION

A mark part of the bearing is pointed to the out-side.

CAUTION

Install the bearing with the special tool.

Install the new oil seals (, ) to the movable drivenface with the special tool.

Apply SUPER GREASE Ato the lip of oil sealsand groove of movable driven faces inside.

Super Grease AInsert up to contact to the stopper.

ENGINE 3-34

Pin

Spacer

Install the movable driven face seat .

Install the movable driven face to the fixed drivenface .

Position the two O-ring . Install the pin at three places on the driven face

hub. Apply SUPER GREASE Alightly to the cam part

where the pins are placed.

When reinstalling the movable dirven face to thefixed dirven face, make sure that the oil seal ispositioned properly.

CAUTION

The seat is installed rotatable naturally.The O-ring get damaged, in case of installed byforce.

CAUTION

Super Grease A

Install the spring . Install the clutch shoe assembly and nut .

Insert as guide the rim.

3-35 ENGINE

Insert the V-belt between the driven faces as deepinside as possible while pulling the movable drivenface all the way outside to provide the maximum beltclearance.

Thoroughly clean the clutch housing to be freefrom oil and position it over the clutch shoe assem-bly.

Tighten the clutch housing nut to the specifiedtorque with the special tool.

Tighten the clutch shoe nut to the specified torquewith the special tool.


Clutch shoe nut : 40~60 Nm (4.0~6.0 kgm)


Clutch housing nut : 40~60 Nm (4.0~6.0 kgm)

The V-belt should be positioned so that thearrows on the belt periphery point the normalturning direction.The V-belt contact face on the driven facesshould be thoroughly cleaned to be free from oil.

CAUTION

ENGINE 3-36

MOVABLE DRIVE

Install the roller to the movable drive face .

Mount the three dampers on the movable driveplate and install it on the movable drive face .

Position the O-ring on the movable drive face.

3-37 ENGINE

Install the movable drive face cover .

Insert the spacer .

Position the movable drive face subassembly on thecrankshaft as shown in the photo.

Install the fixed drive face . Tighten the kick starter driven nut to the specified

torque with the special tool.

Fill SUPER GREASE Ain the groove providedinside sliding surface of the kick driven gear andinstall it on the end of the crankshaft. Wipe offexcess grease.

Install the spring and spacer .

Make sure that the movable drive plate is fullypositioned inside, or the weight roller may comeoff.

CAUTION

Thoroughly clean the V-belt contact to be from oil.

CAUTION

Conrod holder : 09910-20115

Kick starter driven nut : 40~60 Nm (4.0~6.0 kgm)

Super Grease A

ENGINE 3-38

Install the E-ring .

Continue turning the fixed drive face by hand untilthe belt is seated in and both the drive and drivenfaces will move together smoothly without slip.

Fill the final gear box with engine oil up to the levelhole.

Tighten the oil level bolt to the specified torque.

KICK STARTER

110

130

Replace

OverhaulTransmission oil capacity

Oil level bolt : 9~15 Nm (0.9~1.5 kgm)

3-39 ENGINE

Concur with the mark.

13

Apply SUPER GREASE Alightly on the kickstarter shaft rolling surface and install it on thecrankcase cover.

Position the kick starter shaft return spring and hookthe spring end on the crankcase cover boss .

Super Grease A

Tighten the kick starter lever bolt to the specifiedtorque.

Install the kick starter lever as shown in the illustra-tion.

CAUTION

Install the clutch cover and kick starter lever .

Kick starter lever bolt : 8~12 Nm (0.8~1.2 kgm)

ENGINE 3-40

Locating pin

Position the ring so that the marking is on upside.

CORRECT INCORRECT

PISTON

Install the piston rings on the piston.1st - Keystone ring2nd - Barrel face ring

Expander ring

It is extremely important that, when the piston is fedinto the cylinder, each ring in place should be sopositioned as to hug the locating pin as shown in theillustration.

Position the ring so that the marking is on upside.

CAUTION

3-41 ENGINE

OutsideInside

Apply engine oil on the piston pin and install the pis-ton to the conrod.

The circlip should be mounted in such a position thatthe mating ends of the circlip do not coincide with thegroove portion of the piston.

Position the cylinder base gasket. Apply engine oil on the piston and cylinder wall sur-

faces and install the cylinder over the piston carefully. Install the cylinder head gasket and cylinder head.

Tighten the cylinder head nut to the specification, andtighten it diagonally several times as shown in theillustration.

The arrow mark on the piston head shouldpoint the exhaust side.

CAUTION

Cylinder head nut : 8~12 Nm (0.8~1.2 kgm)

ENGINE 3-42

OIL PUMP AND INTAKE PIPE

Apply SUPER GREASE Ato the oil pump drivengear and install it to the crankcase.

Install the oil pump and tighten it to the specifiedtorque.

Super Grease A

Oil pump bolt : 3~5 Nm (0.3~0.5 kgm)

3-43 ENGINE

Install the reed valve gasket , intake pipe gasket and intake pipe with reed valve to thecrankcase.

MAGNETO

Degrease the tapered portion of the crankshaft andalso the magneto rotor.

Install the stator . Install the key .

ENGINE 3-44

Install the rotor . Apply THREAD LOCK 1324to the rotor nut and

tighten it to the specified torque with the special tool.

Thread Lock 1324


Magneto rotor nut : 35~45 Nm (3.5~4.5 kgm)

Install the fan case . Install the magneto lead wire and starting motor lead

wire.

Install the cooling fan .

Install the cooling fan cover .

3-45 ENGINE

MUFFLER Tighten the exhaust pipe bolts and muffler mounting

bolts to the specified torque.Exhaust pipe bolt : 8~12 Nm (0.8~1.2 kgm)Muffler mounting bolt : 18~28 Nm (1.8~2.8 kgm)

FUEL SYSTEM

CARBURETOR 4- 1

REMOVAL 4- 1

DISASSEMBLY 4- 2

INSPECTION 4- 4

REASSEMBLY AND REMOUNTING 4- 5

FUEL TANK 4- 7

REMOVAL 4- 7

CLEANING 4- 8

REMOUNTING 4- 8

OIL PUMP 4- 8

FUEL PUMP 4- 9

CONTENTS

4

4-1 FUEL SYSTEM

REMOVAL Open the seat, and separate the helmet box by

removing the four lock nuts.

Remove the rear shock absorber mounting lower bolt.

CARBURETOR

FUEL SYSTEM 4-2

Disconnect the air vent hose , oil hose , and fuelhose .

Remove the carburetor top cap , and disconnectthe throttle cable .

Remove the carburetor by loosening the mountingbolts and clamp screw .

DISASSEMBLY Remove the thermoelement assembly.

4-3 FUEL SYSTEM

Do not attempt to disassemble the thermoelementassembly.It is not serviceable.

CAUTION

Remove the float chamber .

Remove the float by removing the screw andpin .

Remove the needle valve .

FUEL SYSTEM 4-4

Inspect the valve surface for worn

Foreign matter

,

When removing the pilot airscrew, record the revolu-tions until tighten completly.

CAUTION

Remove the throttle stop screw and pilot air screw .

Remove the main jet and needle jet .

NEEDLE VALVE INSPECTIONIf foreign matter is caught between the valve seat andthe needle, the gasoline will continue flowing and causeit to overflow. If the seat and needle are worn beyond thepermissible limits, similar trouble will occur. Conversely,if the needle sticks, the gasoline will not float chamber.Clean the float chamber and float parts with gasoline. Ifthe needle is worn as shown in the illustration, replace ittogether with a valve seat. Clean the fuel passage of themixing chamber with compressed air.

INSPECTIONCheck following items for any damage or clogging. Pilot jet Main jet Pilot air screw Needle jet air bleeding hole Float Gasket Pilot outlet and bypass holes

4-5 FUEL SYSTEM

REASSEMBLY AND REMOUNTING Reassemble following items.

Pilot air screw Throttle stop screw Main jet Needle jet

Install the needle valve and float on the carbu-retor body.

Install the float pin and tightened the screw . Install the gasket and float chamber.

Install the thermoelement assembly.

FUEL SYSTEM 4-6

Install the carburetor top cap.

Install the carburetor assembly.

Install the air vent hose , oil hose and fuel hose .

4-7 FUEL SYSTEM

FUEL TANK

REMOVAL Remove the low leg shield .

Disconnect the fuel hose .

Disconnect the fuel level gauge lead wire .

Remove the six fuel tank mounting bolt.

FUEL SYSTEM 4-8

yy

yy

yyyy

yyyy

yyyy

yyyy

yyyy

yyyy

yyy

yyy

yyy

y

yyy

yyy

yyy

CLEANINGDust from the fuel tank tends to bulid up in the fuel filterwhich, when the fuel filter has been neglected for a longperiod, inhibits the flow of fuel.Remove the dust from, the fuel filter using com-pressed air.

REMOUNTINGRemount the fuel tank in the reverse of removal.

OIL PUMP

AIR BLEEDINGWhenever evidence is noted of some air having leakedinto the oil pipe from the oil tank in a machine brought infor servicing, or if the oil pump has to be removed forservicing, be sure to carry out an air bleeding operatingwith the oil pump in place before returning the machineto the user. To bleed air, hold the machine in standstill condition.Loosen the air bleeding screw to let out air and aftermaking sure that the trapped air has all been bled, tight-en the air bleeding screw completely.

4-9 FUEL SYSTEM

During this inspection, strictly follow the follow-ing points.The machine should be rested on the center

stand.Do not touch the rear wheel while running the

engine.

CAUTION

CCI Oil gauge : 09900-21602

CHECKING OIL PUMPUse the special tool, to check the pump for capacity bymeasuring the amount of oil the pump draws during thespecified interval. Remove the left side cover. Have the CCI Oil gauge filled with HYOSUNG HYPOL

OIL and connect it to the suction side of the pump. Run the engine at 3,000 rpm. Holding engine speed at the same 3,000 rpm, let the

pump draw for 5 minutes. For this operation, thereading taken on the device should be 6 ..

1.0 ~ 1.2 (at 3,000 rpm for 5 minutes)

Engine oil discharge amount

Stop up an entrance of the hose, to prevent thatthe fuel leak out.

CAUTION

FUEL PUMP

REPLACE Remove the rear shock absorber, and support the

center stand by a 70 mm wooden block. Open the seat, and remove the trunk by loosing the

four nuts. Remove the one lock nut of fuel pump.

Disconnect the inlet hose.

Disconnect the vacuum hose and outlet hose. Remount in the reverse of removal after replacing the

fuel pump.

ELECTRICAL PARTS 5- 1

IGNITION/CHARGING SYSTEM 5- 2

IGNITION COIL 5- 2

STATOR COILS 5- 3

REGULATOR/RECTIFIER 5- 4

STARTER SYSTEM 5- 4

STARTING MOTOR INSPECTION 5- 5

STARTER RELAY INSPECTION 5- 6

FUEL LEVEL GAUGE 5- 7

OIL LEVEL CHECK LIGHT 5- 8

THERMOELEMENT 5- 9

SWITCHES INSPECTION 5-10

BATTERY 5-11

ELECTRICAL SYSTEM

5

CONTENTS

5-1 ELECTRICAL SYSTEM

Front turn signalRH/LH

Head Lamp

Wiring harness

Speedometercable

Brake hose

Rear brake cable

Turn signal cable

Regulator

ELECTRICAL PARTS

Ignition coil Thermolement assembly Fuel level gauge Oil level gauge

ELECTRICAL SYSTEM 5-2

lgnitioncoil

Spark plug

Engine stopswitch

CDIunit

Stator

Lightingswitch

Regulator/Rectifier

Battery12V 3AH(MF)H/L T/L M/L

12V15W2

12V5W

12V1.7W2

Spark

Yellow

BlackBlack(-)

Red(+)

IGNITION/CHARGING SYSTEM

Over 8 mmSpark performance

Electro tester : 09900-28106

IGNITION COIL Check the ignition coil with electro tester. Test the ignition coil for sparking performance. Test

connection is as indicated. Make sure that the three-needle sparking distance is at least 8mm. Test it atleast for 5 minutes.


B/R

Ground

Plug cap

Stator coil resistance

Lead wire of testerStandard resistance

(Red) (Black)

Lighting coil

Charging coil

Exciting coil

Pick-up coil

Y/W

W/R

B/R

Br

Ground

Ground

Ground

W

0.54 ~ 0.80

0.69 ~ 1.03

220 ~ 260

90 ~ 110

C.D.I. UNIT Using the pocket tester (R 1 range), measure the

resistance between the lead wire in the following table.

Unit :

Unit :

When making this test, be sure that the battery isin fully-charged condition.

CAUTION

CHARGING OUTPUT CHECKStart the engine and keep it running at 5,000 rpm with lightingswitch turned ON.Measure the DC voltage between the battery terminal and with a pocket tester.If the tester reads under or over following specification, checkthe no-lead performance or replace the regulator/rectifier.

Pocket tester : 09900-25002Engine tachometer : 09900-26006


13.0 ~ 16.0 V (at 5,000 rpm)Standard charging output


Check the ignition coil with the pocket tester.

Primary

Secondary

0.19 ~ 0.24

5.4 ~ 6.6

Ignition coil resistance

W/BLB/Y

B/W BrW

B/R

STATOR COILS Using the pocket tester, measure the resistance

between the lead wire and ground. If the resistancechecked is incorrect, replace the coil.

Probe of tester to :

P

robe

of t

este

r to

:

B/Y

B/Y

W/BL

W/BL

B/R

B/R

B/W

B/W

W

W

Br

Br

14~18

3~5

7~11

12~16

10~14

7~10

3~4.5

6~8

5~7

3~4

25~35

1.2~2.5

7~10

3~4.5

5~8

5~7

1.2~2.5

27~37


Starter relay

IG switch Starter switch

Y/G

R

Fuse

Brake switch

BatteryW/B

Point

R/W

Startermotor

More than 17 V (at 5,000 rpm)Standard no-load performance

of A.C. generator

NO-LOAD PERFORMANCE OF A.C. GENERATOR Disconnect the magneto lead wire coupler. Start the engine and keep it running at 5,000 rpm. Using a pocket tester, measure the AC voltage

between the three lead wire. If the tester reading is asfollows, magneto is in good condition.


REGULATOR/RECTIFIER Disconnect the coupler. Using the pocket tester(1 Range), measure the

resistance between the terminals as shown in the fol-lowing table. If the resistance checked is incorrect,replace the regulator/rectifier.

Pr

obeo

fteste

rto:

Probe of tester to:

1 2 3 4

1 2 3 4

50 ~ 230

50 ~ 260

10 ~ 100

1

2

3

4

STARTER SYSTEM

The starter system is shown in the diagram below: namely, the starting motor, starter relay, starter switch and battery.Depressing the starter switch (on the right handlebar switch box) while squeezing the front or rear brake lever energizesthe relay, causing the contact points to close which connects the starting motor to the battery.

Unit :


Segment

STARTING MOTOR REMOVAL AND DISASSEMBLYRemove the starting motor.Disassemble the starting motor as shown in the illustration.

Service limit 4 mmCarbon brushes wear

Service limit 4 mmCommutator under cut

STARTING MOTOR INSPECTIONCARBON BRUSHESWhen the brushes are worn, the motor will be unable toprocedure sufficient torque, and the engine will be diffi-cult to turn over. To prevent this, periodically inspect thelength of the brushes and replace them when they aretoo short or chipping.

COMMUTATORIf the commutator surface is dirty, starting performancewill decrease. Polish the commutator with #400 or simi-lar fine emery paper when it is dirty. After polishing wipethe commutator with a clean dry cloth.Measure the commutator under cut .




ARMATURE COILUsing the pocket tester, check the coil for open andground by placing probe pins on each commutator seg-ment and rotor core (to test for ground)and on any twosegments at various places (to test for open), with thebrushes lifted off the commutator surface.If the coil is found to be open-circuited or grounded,replace the armature. Continuous use of a defectivearmature will cause the starting motor to suddenly fail.

STARTER RELAY INSPECTION Disconnect the starter relay lead wire coupler.

Check the coil for open, groundand ohmic resis-tance. The coil is in good condition, if the resistanceis as follows.

0 ~ 70 Starter relay standard resistance


B/W

Y/B

Fuel level gauge

Fuel tank

O

FUEL LEVEL GAUGE

FUEL LEVEL METER/GAUGEFUEL METER INSPECTIONTo test the Fuel Meter two different checks may beused.The first, and simplest test will tell if the meter is operat-ing but will not indicate the meters accuracy throughoutthe range. To perform this test, lift the seat and removethe right frame cover, then disconnect the B/W and Y/Blead connector of the fuel gauge sending unit. Connecta jumper wire between B/W and Y/B wires coming fromthe main wiring harness. With the ignition switch turnedON, the fuel meter should indicate F.

The second test will check the accuracy of the meter inthe full and empty positions. Connect a 90 resistorbetween the Y/B and B/W lead wires. The fuel meter isnormal if its pointer indicates the E(empty) positionwhen the specified voltage is applied to the circuit and ifits pointer indicates the F(full) position when the resistoris changed to 10 .


Oil level switch

IG switch

Battery

Oil level check light

F

1/2

E

F(Full)

1/2

E(Empty)

10 0- 6

+ 10

0

38

90

Relation between the position of the fuel gauge float and resistance

Float position Resistance

OIL LEVEL CHECK LIGHT

FUEL GUAGE SENDING UNIT INSPECTION Disconnect the lead wires coming out of the fuel

gauge and check resistance of each position. If the resistance measured is incorrect, replace the

fuel gauge assembly with a new one. The relation between the position of the fuel gauge

float and resistance is shown in the following table.

If either one or both indications are abnormal, replacethe fuel meter with a new one.


BattaryPTC

Regurator/Rectifier

B/RR

Y/W R/W

Magneto

Switch


OIL LEVEL CHECK LIGHT INSPECTIONDisconnect the L/W and B/W lead connector of the oillevel check light.Connect a jumper wire between L/W and B/W wirescoming from the main wiring harness. With the ignitionswitch turned ON, the oil level check light should flash.If there is no flash, check the wiring harness continuityand the bulb blown out.

OIL LEVEL SWITCH INSPECTIONCheck the oil level switch for continuity between the leadwire. If the tester does not show the value of 0 ~ 1 when the switch ring is in bottom position, file the contactsurface or replace the unit.

THERMOELEMENT


Gr

Y/W

ON

OFF

W/B

Y/G

ON

OFF

O

W/B

ON

OFF

B/W

G

ON

OFF

B/W B/R R O L/W

LOCK

OFF

ON

C

Lg Sb B

L

R

This check should be carried out when the carbu-retor is cold.

CAUTION

INSPECTION Disconnect the thermoelement coupler . Connect the thermoelement coupler to a 12V bat-

tery and touch the thermoelement to check thetemperature being raised.The thermoelement should become heated to atemperature more than that of human body withinfive minutes. If not, replace with new one.


SWITCHES INSPECTION

Inspect each switch for continuity with the pocket testerreferring to the chart. If it is found any abnormality,replace the respective switch assembly with new one.

WIRE COLORB BlackL BlueG GreenGr GraySb Light blueLg Light greenO OrangeR RedW WhiteY YellowB/R Black with Red tracerB/W Black with White tracerW/B White with Black tracerY/W Yellow with White tracerY/G Yellow with Green tracerL/W Blue with White tracer

LIGHTING SWITCH

TURN SIGNAL LAMP SWITCH

HORN SWITCH

IGNITION SWITCH

STARTER SWITCH

FRONT AND REAR LAMP SWITCH


CapFilter

Safety valve

Pole plate

Pole plate

Separator(fiberglass plate)

BATTERY

CAUTION OF BATERY ELECTROLYTETREATMENT Pay attention that the battery electrolyte not be stain

the chasis or the humanbody. If be stain the chasis or the humanbody, at once

wash a vast quantity of water.When it be stained, clothes should come into being ahole or painting should take off.Be cured from a doctor.

When the battery electrolyte was droped the surfaceof land, wash a vast quantity of water.Neutralize by hydroxide, bicarbonate of soda and soon.

INITIAL CHARGINGFILLING ELECTROLYTE Remove the aluminum tape sealing the battery

electrolyte filler holes .

BATTERY

Type

Capacity

Standard electrolyte S.G.

YT4L-BS

12V, 3AH/10HR

1.32(at 20)

After filling the electrolyte completely, use theremoved cap as the sealed caps of battery-fillerholes.

Do not remove or pierce the sealed areas ofthe electrolyte container.

CAUTION

Remove the caps .


Make sure air bubbles are coming up each elec-trolyte container, and leave in this position for aboutmore than 20 minutes.

Take precaution not to allow any of the fluid tospill.

The electrolyte container insert at right anglesso that it is not sloped.

CAUTION

Insert the nozzles of the electrolyte container into thebatterys electrolyte filler holes, holding the containerfirmly so that it does not fall.

NOTE: If no air bubbles are coming up from a filler port, tap thebottom of the two or three times.Never remove the container from the battery.

Clean completely in case that the electrolyte isadhered at the filler hole.

Once install the caps to the battery, do notremove the caps.

CAUTION

After confirming that the electrolyte has entered thebattery completely, remove the electrolyte containersfrom the battery. Wait for around 20 minutes.

Insert the caps into the filler holes, pressing infirmly so that the top of the caps do not protrudeabove the upper surface of the batterys top cover.


Time

(Minutes)

(at 25)

(Minutes)Time

(at 0~40)

Battery charged condition

Volta

ge

Volta

ge

NOTE: Initial charging for a new battery is recommended if twoyears have elapsed since the date of manufacture.

Using the pocket tester, measure the battery voltage.The tester should indicate more than 12.5-12.6V(DC)as shown in the Fig. If the battery voltage islower than the specification, charge the battery with abattery charger.

CAUTION OF BATTERY TREATMENTThe battery is needed attention generally as occur flammability gas.If does not, it should be explosion and severe accident.Pay attention to the following points. Prohibit positively that come in contact with short, spark or firearms. The battery recharge where be well-ventilated wide place.

Prohibit positively at the shut tight room.

seconds

Standard

Fast

BATTERY CHARGING CURRENT

RECHARGING OPERATION Using the pocket tester, check the battery voltage. If

the voltage reading is less than 12.0V(DC), rechargethe battery with a battery charger.

When recharging the battery, remove the batteryfrom the motorcycle.

Do the battery by standard charging usually.

After recharging, wait for more than 30 minutes andcheck the battery voltage with a pocket tester.

If the battery voltage is less than 12.0V, recharge thebattery again.

If the battery voltage is still less than 12.0V afterrecharging, replace the battery with a new one.

0.4A 5~10 Hours

4A 30 Minutes

Charging equipment of this motorcycle isdesigned for the MF(Maintenance Free) battery.

No use except the specificated battery.

WARNING

NOTE: When a battery is left for a long term without using, it issubject to discharge. When the motorcycle is not usedfor more than 1 month(especially during the winter sea-son), recharge the battery once a month at least.

CHASSIS

FRONT WHEEL 6- 1

FRONT BRAKE 6- 7

FRONT FORK 6-14

STEERING 6-18

REAR WHEEL AND REAR BRAKE 6-22

CONTENTS

6

6-1 CHASSIS

Do not operate the front brake lever while dis-mounting the caliper.

CAUTION

REMOVAL AND DISASSEMBLY Remove the front brake caliper by removing the

mounting bolts .

FRONT WHEEL

CHASSIS 6-2

Remove the front axle nut. Support the motocycle by jack or wooden block. Remove the front wheel and speedometer gear box

by removing the front axle shaft.

Remove the disc plate by removing the bolts.

Remove the spacer .


Remove the oil seal with the special tool.

6-3 CHASSIS

Wheel bearing remover : 09941-50111

Drive out the both bearing with the special tool in the fol-lowing procedures. Insert the adapter into the bearing. After inserting the wedge bar from the opposit side,

lock the wedge bar in the slit of the adapter. Drive out the bearing by knocking the wedge bar.

The removed dust seal and bearing should bereplaced with new ones.

CAUTION

Wheel rim runout(Axle and Radial)

Service limit 3.0 mm

INSPECTIONWHEEL RIMMake sure that the wheel rim runout does not exceedthe service limit when checked as shown.An excessive runout is usually due to worn or loosewheel bearings and can be reduced by replacing thebearings. If bearing replacement fails to reduce therunout, replace the wheel.

TIREInspect the tires for wear and damage, and check thetire tread depth as shown. Replace a badly worn or dam-aged tire. A tire with its tread worn down to the limit(interms of tread depth)must be replaced.

Dial gauge(1/100 mm) : 09900-20606Magnetic stand : 09900-20701

CHASSIS 6-4

Right side Left side

Bearing(L)

Bearing(R) Spacer

Clearance Bearing(L)

S hS hA lv niaaell

3

I nduI nduM ulti-M ulti-purpur

strialstrialposepose G r

easeG rease

Tire depthservice limit

Front 1.6 mm

1.6 mmRear

TIRE PRESSURECold inflation

Normal riding

Solo riding Dual riding

kg/

1.25

2.00

kPa

123

196

kg/

1.75

2.25

kPa

172

221

Front

Rear

Check the tire pressure, and examine the value for evi-dence of air leakage.

REASSEMBLY AND REMOUNTINGReassemble and remount the front wheel in the reverseorder diassembly and removal, and also carry out thefollowing steps.

WHEEL BEARING Apply SUPER GREASEAto the bearings before

installing.

Install the wheel bearings by using the special tool.Super GreaseA

Bearing installer set : 09924-84521

First install the wheel bearing for left side.

CAUTION

6-5 CHASSIS

Front brake disc bolt : 18 ~ 28 Nm(1.8 ~ 2.8 kgm)

Oil seal installer : 09923-55131

OIL SEAL Install the oil seal with the special tool.

Install the spacer .

DISC PLATE Install the disc plate and tighten them to the specified

torque.

SPEEDOMETER GEAR BOX When installing the speedometer gear box, align the

two drive pawls with the two recesses of thewheel hub.

CHASSIS 6-6

After touching the speedometer gear box tothe stopper , tighten the axle shaft.

CAUTION

FRONT WHEEL Tighten the front axle nut to the specified torque.

Tighten the caliper mounting bolts to the specifiedtorque.

Front axle nut : 33 ~ 52 Nm(3.3 ~ 5.2 kgm)

Front brake caliper mounting bolt : 18 ~ 28 Nm(1.8 ~ 2.8 kgm)

6-7 CHASSIS

FRONT BRAKE


CAUTION

BRAKE PAD REPLACEMENT Remove the caliper by removing the brake caliper

mounting bolts .

CHASSIS 6-8

Replace the brake pads as a set, otherwise brak-ing performance will be adversely affected.

CAUTION

Reassemble it after remove the brake pads .

Never re-use the brake fluid left over from the lastservicing and stored long periods.

CAUTION

CALIPER REMOVAL AND DISASSEMBLY Remove the brake hose and catch the brake fluid

in a suitable receptacle. Remove the caliper mounting bolt .

Remove the caliper. Remove the brake pads. Remove the pad holder .

Remove the spring .

6-9 CHASSIS

Do not use high pressure air to prevent pistondamage.

CAUTION

Place a rag over the piston to prevent popping up.Force out the piston with a air gun.

Remove the dust seal and piston seal .

CALIPER INSPECTIONInspect the caliper cylinder bore wall for nicks, scratchesor other damage.Inspect piston for damage and wear.

Inspect each rubber part for damage and wear.

CHASSIS 6-10

{{

CALIPER REASSEMBLYReassemble and remount the caliper in the reverseorder of removal and disassembly, and also carry out thefollowing steps.

Wash the caliper components with fresh brakefluid before reassembly. Never use cleaning sol-vent or gasoline to wash them. Apply brake fluidto the caliper bore and piston to be inserted intothe bore.

CAUTION

Silicone Grease

Apply SILICONE GREASE to the caliper holder.

DISC PLATE REMOVAL AND DISASSEMBLY Remove the front wheel.(Refer to page 6-2) Remove the disc plate.(Refer to page 6-2) Install the disc plate.(Refer to page 6-4)

SPECIFIED TORQUE

Item

Nm

18 ~ 28

20 ~ 25

kgm

1.8 ~ 2.8

2.0 ~ 2.5

Bleed the air from brake fluid circuit afterreassembling caliper.(Refer to page 2-9)

WARNING

Disc thickness Service limit 3.5 mm

Micrometer(0 ~ 25mm) : 09900-20201

DISC PLATE INSPECTION Check the disc for wear with a micrometer. Its thick-

ness can be checked with disc and wheel in place.Replace the disc if the thickness exceeds the servicelimit.

6-11 CHASSIS

With the disc mounted on the wheel, check the discfor face runout with a dial gauge as shown. Replacethe disc if the runout exceeds the service limit.

MASTER CYLINDER REMOVAL AND DISASSEMBLY Remove the handlebar cover. Disconnect the front brake lamp switch lead wires.

Dial gauge(1/100 mm) : 09900-20606Magnetic stand : 09900-20701

Disc runout Service limit 0.3 mm

Completely wipe off any brake fluid adhering toany part of motorcycle. The fluid reacts chemical-ly with paint, plastics, rubber materials, etc.

CAUTION

Place a cloth underneath the union bolt on the mastercylinder to catch spilled drops of brake fluid. Unscrewthe union bolt and disconnect the brake hose/mastercylinder joint.

Remove the master cylinder.

CHASSIS 6-12

} Remove the brake lever and brake switch .

Remove the dust boot .

Remove the circlip with the special tool.

Remove the piston/primary cup with return spring . Remove the reservoir cap and diaphragm . Drain brake fluid.

Snapring pliers : 09900-06108

6-13 CHASSIS

Boot

Circlip

Second cap

PistonPrimary cap

spring

Master cylinder

Upside

Handlebar

Clearance

MASTER CYLINDER INSPECTIONInspect the master cylinder bore for any scratches orother damage.Inspect the piston surface for scratches or other dam-age.Inspect the primary cup and dust boot for wear or dam-age.

MASTER CYLINDER REASSEMBLY ANDREMOUNTINGReassemble and remount the master cylinder in thereverse order of removal and disassembly, and alsocarry out the following steps.

Wash the master cylinder components with freshbrake fluid before reassembly. Never use clean-ing solvent or gasoline to wash them.Apply brake fluid to the cylinder bore and all theinternals to be inserted into the bore.

CAUTION

Bleed air after remounting the master cylinder.

CAUTION

Reassemble and remount the master cylinder.(Referto page 6-11)

When remounting the master cylinder on the handle-bar, first tighten the clamp bolt for upside.

CHASSIS 6-14

FRONT FORK


CAUTION

REMOVAL AND DISASSEMBLY Remove the front leg shield. Remove the front brake caliper by removing the

mounting bolts.

6-15 CHASSIS

Remove the front axle nut. Support the motorcycle by jack or wooden block. Remove the front wheel by removing the front axle

shaft.

Loosen the front fork bolt, then draw out the forkspring.

Loosen the front fork lower clamp bolts.

Invert the fork and stroke it several times to removethe oil.

Hold the fork inverted for a few minutes.

Remove the socket bolt with the hexagon wrench. Seperate the fork pipe and pipe seat .

CHASSIS 6-16

Remove the dust boot and stopper ring .

The oil seal removed should be replaced with anew oil seal.

CAUTION


INSPECTION Inspect pipe seat for wear and damage.

Inspect fork pipe and bottom case sliding surfaces forany scuffing or flaws.

Remove the oil seal by using the special tool.

6-17 CHASSIS

290.9

Up side

}}

Fork spring free length Standard 290.9 mm

FORK SPRING Measure the fork spring free length.

REASSEMBLY AND REMOUNTINGReassemble and remount the fork in the reverse order ofremoval and disassembly, and also carry out the follow-ing steps.

FRONT FORK BOLT Apply BOND 1215and THREAD LOCK 1324to

the fork bolt and tighten the bolt with specified torque.

CUSHION SPRING When installing the front fork spring, the close end

should position upside.

Bond 1215

Thread Lock 1324

Front fork bolt : 35 ~ 55 Nm(3.5 ~ 5.5 kgm)

TELLUS # 37

50 cc(One side)

Fork oil type

Capacity

FORK OIL For the fork oil, be sure to use a front fork oil whose

viscosity rating meets specification

Documents

hyosung-SF50 Rush