yamaha neo's 50-service manual (02)

2002

SERVICE MANUAL

YN50 5RN-AE1

YN50SERVICE MANUAL

© 2002 Yamaha Motor España, S.A.First Edition, September 2002

All rights reserved.The reprinting or use of this material withoutthe written authorisation of Yamaha Motor

España, S.A is forbidden.Printed in Spain.

WARNING

This Manual was written by Yamaha Motor España, S.A. principally for the use of Yamaha/MBKagents and qualified mechanics. As it is not possible to give full mechanical instructions in a manual,it is presumed that the persons using the book to carry out the maintenance and repair ofYamaha/MBK motorcycles have a basic knowledge of the concepts and procedures inherent in thetechnology of motorcycle repair. Without such knowledge any attempt to repair or service thismodel may cause problems in its use and/or safety. Yamaha Motor España, S.A., is continually trying to improve all models which it manufactures.Authorised Yamaha/MBK agents will be notified of all significant modifications and changes in thespecifications or procedures and these will appear where applicable in future editions of thismanual.

PARTICULARLY IMPORTANT INFORMATIONThis material used the following notation.

s A danger symbol means ATTENTION, BE CAREFUL, YOURSAFETY IS IN DANGER!

WARNING Non-compliance with a WANING may cause the serious injury ordeath of the driver, a bystander or the person inspecting ofrepairing the mortorcycle.

ATTENTION: ATTENTION indicates the special precautions which should betaken in order to avoid damage to the motorcycle.

NOTE: NOTE provides key information to make the procedures easierand clearer.

HOW TO USE THIS MANUALFORMAT OF THIS MANUALThis manual is composed of chapters on the main subject categories (See “Illustrated Symbols”).First heading : This is a chapter with a symbol at the top right-hand side of each page.Second heading : This title appears at the top of each page to the left of the chapter symbol. (For the “Inspection and periodic adjustments” chapter the third heading appears) Third heading : This is a final heading.

MANUAL FORMATAll procedures in this manual are organised sequentially, step by step. The information has beencompiled to make reading easy for the mechanic and to provide useful reference material whichcontains ample explanations of all disassembly, repair, assembly and inspection procedures. Aparticularly important procedure is placed between a lines of asterisks “**” with each procedu-re preceded by “•”.

IMPORTANT CHARACTERISTICS• Data and special tools are put in a box preceded by a corresponding symbol .• A number within a circle indicates the number of a part, and an alphabetical letter within a

circle indicates data or an alignment mark , everything else is indicated by a letter within abox .

• The conditions of defective components will precede an arrow symbol and the course of actionto be followed will follow the symbol .

DETAILED DIAGRAMEach chapter provides detailed diagrams before each disassembly section, for the easy identifica-tion of disassembly/assembly procedures.

ILLUSTRATED SYMBOLS(See illustration)Illustrated symbols to are designed astabs to be followed with the thumb to indicatethe chapter number and the index.

General information Specifications Periodic inspection and adjustment General overhaul of the engine Carburation Chassis Electrical system Troubleshooting

Illustrated symbols to 15 will be used toidentify the specifications which appear in thetext.

Refill with fluid10 Lubricant11 Special tool12 Tightening 13 Wear limit, clearance14 Engine speed15 Ω V, A

Illustrated symbols 16 to 23 of detailed dia-grams, indicate the degree of lubricant andthe location of the lubrication point.

16 Apply engine oil17 Apply gear oil18 Apply molybdenum disulphide oil19 Apply grease to wheel bearings20 Apply grease with lightweight lithium soap

base21 Apply molybdenum disulphide grease22 Apply bonding agent (LOCTITE®)23 Use a new part.

INSP/ADJ

CHAS

TRBL/SHTG

SPEC

ENG

CARB

GENINFO

NEW

11

13

15

16

19

22

10

12

14

23

18

21

17

20

ELEC

SPEC 2SPECIFICATIONS

INSPADJ 3

PERIODIC INSPECTIONAND ADJUSTMENTS

ENG 4GENERAL OVERHAUL OFENGINE

CARB 5CARBURATION

CHAS 6CHASSIS

ELEC 7ELECTRICAL SYSTEM

INDEX

TRBLSHTG 8TROUBLESHOOTING

GENERAL INFORMATION GEN/INFO 1

GEN/INFO 1

GEN/INFO

CHAPTER 1GENERAL INFORMATION

IDENTIFICATION OF THE SCOOTER…………………………………………1-1SERIAL NUMBER OF THE FRAME …………………………………………1-1ENGINE SERIAL NUMBER……………………………………………………1-1

IMPORTANT INFORMATION …………………………………………………1-2CHANGE OF ALL PARTS ……………………………………………………1-2OIL SEALS AND O-RINGS……………………………………………………1-2SEALING WASHERS/PLATE AND KEYS……………………………………1-2BEARING AND OIL SEALS …………………………………………………1-2CIRCLIPS ………………………………………………………………………1-3

SPECIAL TOOLS …………………………………………………………………1-3FOR SERVICING THE ENGINE ………………………………………………1-3FOR SERVICING THE CHASSIS ……………………………………………1-5FOR ELECTRICAL COMPONENTS …………………………………………1-6

GEN/INFOIDENTIFICATION OF THE SCOOTER

1-1

GENERAL INFORMATIONSCOOTER IDENTIFICATIONFRAME SERIAL NUMBER The serial number of the frame is stampedon the steering head pipe.Frame VTL5AD according standard EU0Frame VTLSA15 according standard EU1Frame VTLSA19 according Mofa Version

ENGINE SERIAL NUMBERThe engine serial number is stamped onthe upper part of the rear left-hand section ofthe gear box.

NOTE:

The first three digits of these numbers identifythe model, the remaining digits are the manu-facturing number of the unit.

NOTE:

The designs and specification are subject tochange without prior notice.

GEN/INFOIMPORTANT INFORMATION

1-2

IMPORTANT INFORMATIONCHANGE OF ALL PARTS1. We recommend that original Yamaha parts

are used as spare parts. Use the oil and/orgrease recommended by Yamaha forassembly and adjustment.

GASKETS, OIL SEALS AND O-RINGS1. All gaskets and o-rings should be replaced

when the engine is overhauled and repaired.All gasket surfaces, the lips of seals and o-rings should be cleaned.

2. Lubricate with grease all correspondingparts and bearings during assembly. Applygrease on the lips of seals.

SEALING WASHER/PLATES AND KEYS1. All washers/plates and keys should be

replaced when they are removed. The loc-king tabs should be folded along the flatparts of the bolts or nuts after correctly tigh-tening them.

BEARINGS AND OIL SEALS1. Install the bearings and oil seals with

their manufacturer’s marks or numbersfacing outwards (i.e. the printed lettersshould on the side exposed to view). Whenthe oil seals are installed, apply a thin layerof light lithium-based grease on the edgesof the seal. Put oil on the bearings whenthey are installed.

ATTENTION:

Do not turn the bearings in compressed airto dry them. This will damage the surfaceof the bearings.

GEN/INFO

IMPORTANT INFORMATION / SPECIAL TOOLS

1-3

CIRCLIPS1. All circlips should be carefully inspected

before assembly. Always replace circlips ofthe piston drum after use. Replace defor-med circlips. When installing a circlip ,ensure that the corner with the sharp edge is placed in the opposing direction tothe thrust it receives. See sectionalview. Axle

SPECIAL TOOLSAppropriate special tools are needed to com-plete and perfect assembly with accuracy.Using correct tools will help to avoid damagecaused by the use of incorrect tools or impro-vised techniques.

FOR SERVICING THE ENGINE1. Engine wheel holding tool

(90890-01235)

2. Engine wheel removal tool(90890-01362)

3. Crankcase separation tool(90890-01135)

GEN/INFOSPECIAL TOOLS

1-4

4. Pulley wheel clamp(90890-01701)

5. Clutch spring compressor (90890-01337)

6. Crankshaft installer crucible... (90890-01274)

7. Crankshaft installer bolt... (90890-01275)


1-5

8. Adaptor (M10)... (90890-01277)

9. Spacer... (90890-01411)

FOR SERVICING THE CHASSIS1. T-shaped handle 2...

(90890-01326)Shock absorber rod support... (90890-01294-A)

2. Counterbalance for insertion of fork seals(90890-01184)

3. Accessory for insertion of fork seals(90890-01186)


1-6

4. Steering nuts wrench(90890-01403)

FOR ELECTRICAL COMPONENTS1. Pocket tester

(90890-03112)

2. Ignition tester(90890-06754)

SPEC 2

SPEC

CHAPTER 2SPECIFICATIONS

GENERAL SPECIFICATIONS …………………………………………………2-1

MAINTENANCE SPECIFICATIONS ……………………………………………2-3ENGINE …………………………………………………………………………2-3CHASSIS ………………………………………………………………………2-5ELECTRICAL SYSTEM ………………………………………………………2-6CABLE ROUTING ……………………………………………………………2-7

SPECGENERAL SPECIFICATIONS

2-1

Model YN50R

Engine:Engine type Reed valve, petrol, 2-stroke, air-cooledArrangement of cylinders One cylinder inclined to the frontCylinder capacity 49.2 ccDiameter and stroke 40.0 x 39.2 mmCompression ratio 11.6:1 5AD 10.2:1 SA15 11:1 SA19Starter system Electrical and pedal kickstart

Lubrication system: Yamaha autolubricationType or grade of oil:

Engine oil 2-stroke air-cooled engine oilTransmission oil SE type 10W30 SAE engine oil

Oil capacity:Oil sump (engine oil) 1.2 LTransmission oil

Periodic change of oil 0.10 LTotal quantity 0.11 L

Air filter: Flue typeFuel:

Type Unleaded petrolFuel tank capacity 6.5 L

Carburettor:Type/Manufacturer PHVA/DELLORTO/PY12,1/GURTNER

Spark plug: 5AD y SA15 SA19Type/Manufacturer BR8HS/N.G.K. BPR4HS/NGKDistance between electrodes 0.6 ~ 0,7 mm 0.6 ~ 0.7 mm

Clutch type: Dry, automatic centrifugal

Transmission:Primary reduction system Helicoidal gearing Primary reduction ratio 52/13 (4.00)Secondary reduction system Straight gearingSecondary reduction ratio 42/13(3.230) 5AD-SA15 45/12(33.750) SA19Type of transmission Automatic one speed

(Trapezoidal belt type)Action Automatic centrifuge type

Chassis:Frame Steel underside of pipe Inclination angle of front axle 26,5°Trail 92.5 mm

Tyres:Size (FR) 120/70-12Size (R) 130/70-12

Tyre pressures (cold):(Front) 1.75 kg/cm2

(Rear) 2.00 kg/cm2

SPECGENERAL SPECIFICATIONS

2-2

Model YN50R

Brakes:Front brake type Disc brakeOperation Right-hand operationRear brake type Drum brakeOperation Left-hand operation

Suspension:Front suspension Telescopic forkRear suspension Balancing unit

Shock absorber:Front shock absorber Spring/oil shock absorberRear shock absorber Spring/oil shock absorber

Travel of wheels:Travel of front wheel 70 mmTravel of rear wheel 60 mm

Electrical system:Ignition system DC-C.D.I. Generating system Magnetic flywheelBattery type or model YB4C-BBattery capacity 12V4AH

Type of headlight: Bulb typeBulb voltage/quantity:

Headlamp 25W/25Wx2Rear light/brake 5/21WIndicator 10Wx4Metre light 1.2Wx2

Warning lights/quantity:Oil 2Wx1Fuel 2Wx1Indicators 2Wx2

SPECMAINTENANCE SPECIFICATIONS

2-3

MAINTENANCE SPECIFICATIONSENGINE

Model YN50R

Cylinder head:Warping limit 0.02 mm

* The lines indicate the measurement

Cylinder:Internal diameter 39.993 ~ 40.012 mm<Limit> <40.1 mm>Taper limit 0.05 mmEccentricity limit 0.01 mm

Piston:Piston size 39.952 ~ 39.972 mm

Measurement point 5 mmPiston clearance 0.034 ~ 0.047 mmFirst clearance 40.50 mm

Piston ring:Cross section 1.5 x 1.8 mm

B x T Distance between ends

(installed) 0.15 ~ 0.35 mm<Limit> <0.6 mm>Lateral clearance 0.03 ~ 0.05 mm

Crank shaft:

Width of crank shaft “A” 37.90 ~ 37.95 mmDeflection limit “C” 0.03 mmConnecting rod big

end clearance “D” 0.2 ~ 0.5 mmFree play from small end “F” 0.4 ~ 0.8 mmFree play “E” 0.004 ~ 0.017 mm


2-4

Model YN50R

Automatic centrifugal clutch:Thickness of clutch shoe 2 mm<Limit> <1 mm>Free length of clutch shoe 29.9 mm

spring Clutch revolutions 3.600±250 rpmClutch binding revolutions 5.600±400 rpm

Transmission:Main axle deflection limit 0.08 mmDrive axle deflection limit 0.08 mm

Choke handle:Type Ratchet typePedal friction force 150 ~ 250 g

Air filter oil grade (oil filter):Oil for foam air filter 2T oil for air-cooled engines

Carburettor:Type/Manufacturer/Quantity PHVA/Dellorto/1 YP12/GURTNER/1Main jet (M.J.) #78/5AD #65//SA15 #74/5AD #62/SA15 #60/SA19Retaining position of jet

needles (J.N.) A12-3/5 A20-3/5 B10A-2/3 B10A-2/3 L3035H-1/3Main air jet (M.A.I.) ø 1.5 ø 1.5 – – –Pilot jet (P.J.) #36/5AD #36/SA15 #38/5AD #38/SA15 #36/SA19Pilot air screw (P.A.S.) 1 1/4 ±

1/4 2 1/8 ±1/8 1 1/8 1 7/8 1 7/8

Valve seat size 1.2 1.4engine idling 1.800 r.p.m. 1.800 r.p.m


2-5

CHASSIS

Model YN50R

Steering system:Steering bearing type Ball bearing

Front suspension:Travel of front shock absorber 70 mmFree length of shock absorber

spring 226 mm<Limit>Spring/stroke ratio (K1) 1.12 Kgf/mm

(K2) 1.78 Kgf/mmOil capacity 45 cm3±1Oil grade 10 W shock absorber oil or equivalent

Rear suspension:Shock absorber travel 60 mmLength of spring coupling 221 mmSpring/stroke ratio (K1) 3.75 Kgf/mm

(K2) 7,10 Kgf/mm

Wheels:Type of front wheel Alloy rimType of rear wheel Alloy rimSize/material of front wheel 12 x 3.5 aluminiumSize/material of rear wheel 12 x 3.5 aluminiumRim run-out limit

Vertical 1.0 mmLateral 1.0 mm

Front disc brakeType SingleExternal diameter and disc

thickness 190.0 x 3.5 mmThickness of pads 4 mm<Limit> <0.8 mmInternal diameter of master cylinder 11 mmInternal diameter of calliper 30.16 mmBrake fluid type DOT 4

Drum brake:Type ShoesInternal diameter of drum 110 mm<Limit> 110.5 mmLining thickness 4.0 mm<Limit> 2.0 mm

Brake leversFree play of brake lever

(right)/position 2 ~ 5 mm /at the end of the leverFree play of brake lever

(left)/position 5 ~ 10 mm /at the end of the lever


2-6

ELECTRICAL SYSTEM

Model YN50R

Ignition system:Type DC-C.D.I.Ignition distribution (A.P.M.S.) 14*/5.000 r/min

C.D.I.:Harnessing coil resistance (colour) 400 ~ 600 Ω a 20 oC (68 oF)

(Black/Red-Black)

Ignition coil:Spark plug electrodes gap 6.0 mmPrimary coil resistance 0.56 ~ 0.84 Ω at 20 °CSecondary coil resistance 5,68 ~ 8,52 KΩ at 20 °C

Charging system:Charging output 0.4 A or more/3.000 rpm/min

1 A or less/8.000 rpm/minCharging coil resistance (colour) 4.8 ~ 7.2 Ω a 20 °C (68 °F) (Black-White)

Lighting system:Lighting output 12 V or more/3.000 rpm/min,

15 V or less/8.000 rpm/minLighting coil resistance (colour) 0.4 ~ 0.6 Ω a 20 °C (68 °F)

(Yellow/Red-Black)

Battery:Type: YB4L-BCapacity 12V4AHSpecific gravity 1280/20 °C

Starter system:Type: Constant mesh type

Starter motor:Output 0.14 kwInduction coil resistance 0.064 ~ 0.079 Ω at 20 °CBrush length 3.9 mm<Limit> <0.9 mm>

Circuit breaker:Type: FuseAmperage/Quantity

Principal 7A x 1

SPECCABLE ROUTING

2-7

CABLE ROUTING

Front brake pipe Rear brake cable Rear brake calliper Rear mudguard Rear warning light Vacuum tube Fuel pipe Speedometer cable Installation10 Breather11 Accelerator cable12 Seat closing cable13 Oil hose14 choke wire

A Insert the seat closing cable through theframe orifice

B Connect the oil tube to the carburettorC Splice the fuel pipe to the cockD Splice the fuel pipe to the carburettorE Press the earth cable and the starter motor

together F Splice all the cables except the brake hose,

without tighteningG Splice to the frame wire harness and throtleH Pass the brake cable through the guide

SPECCABLE ROUTING

2-8

Rectifier/Regulator Main switch Fuel level measurer Horn Ignition coil Spark plug cable Oil level sensor Oil tank C.D.I.

A Splice the electrical installation to the frameB Splice the oil pipe to the tankC Connect the oil pipe to the pumpD Splice the installation to the frameE Tighten the earth cable and the ignition coil

togetherF Pass the speedometer cable through the

guideG Fit the grommet in the small hole of the

underbracket

SPECCABLE ROUTING

2-9

Front break switch Electrical installation Intermittent relay Speedometer assembly Accelerator cable Rear brake cable Choke cable Front brake hose

A Do not pinch the accelerator cable whenassembling the handlebar covers

B Accelerator cable tensioner. Cover afteradjusting

C Connect the brake switch cables in this area D Do not pass the brake pipe through the flan-

ge

INSPADJ 3

CHAPTER 3PERIODIC INSPECTION AND ADJUSTMENTS

INTRODUCTION/PERIODIC MAINTENANCE/LUBRICATION INTERVALS …3-1

REAR BODYWORK AND FOOTREST ………………………………………3-2REMOVAL ………………………………………………………………………3-2INSTALLATION …………………………………………………………………3-3

MUDGUARDS, LOWER COVER AND FRONT PANEL ……………………3-4REMOVAL ………………………………………………………………………3-5INSTALLATION …………………………………………………………………3-5

HANDLEBAR COVERS …………………………………………………………3-5REMOVAL ………………………………………………………………………3-5INSTALLATION …………………………………………………………………3-5

ENGINE ……………………………………………………………………………3-6ADJUSTMENT OF ENGINE IDLING …………………………………………3-6ADJUSTMENT OF FREE PLAY OF TROTTLE CABLE ……………………3-7SPARK PLUG INSPECTION …………………………………………………3-8INSPECTION OF ENGINE OIL LEVEL ………………………………………3-9CHANGE OF TRANSMISSION OIL ………………………………………3-10AUTOLUBE PUMP AIR BLEEDING ………………………………………3-10CLEANING AIR FILTER………………………………………………………3-10

CHASSIS …………………………………………………………………………3-12ADJUSTMENT OF FREE PLAY OF FRONT BRAKE LEVER ………………3-12ADJUSTMENT OF FREE PLAY OF REAR BRAKE LEVER…………………3-12INSPECTION OF BRAKE PADS ……………………………………………3-12INSPECTION OF BRAKE SHOES …………………………………………3-13INSPECTION OF BRAKE FLUID LEVEL …………………………………3-13AIR BLEEDING (HYDRAULIC BRAKE SYSTEM) …………………………3-14STEERING ADJUSTMENT …………………………………………………3-14INSPECTION OF TYRES ……………………………………………………3-15WHEEL INSPECTION ………………………………………………………3-16INSPECTION OF REAR FORK ……………………………………………3-16REAR SHOCK ABSORBER INSPECTION…………………………………3-16

ELECTRICAL SYSTEM…………………………………………………………3-17INSPECTION OF BATTERY …………………………………………………3-17INSPECTION OF FUSES ……………………………………………………3-19ADJUSTMENT OF HEADLAMP BEAM ……………………………………3-20REPLACEMENT OF HEADLAMP BULB …………………………………3-20

INSPADJ

INSPADJ

INTRODUCTION / PERIODIC MAINTENANCE /LUBRICATION INTERVALS

3-1

PERIOD INSPECTION AND ADJUSTMENTSINTRODUCTIONThis chapter includes all information necessary to carry out inspections and adjustments recom-mended. These preventive maintenance procedures, if they are correctly followed, will ensure themost reliable operation of the vehicle and a longer useful life. The need for overhauls and costlyrepairs will be greatly reduced. This applies both to vehicles which are already in service and tonew vehicles which are ready for sale. All service technicians should familiarise themselves withthe entire chapter.PERIODIC MAINTENANCE / LUBRICATION INTERVALS

ODOMETER READING( x 1.000 km) ANNUAL

N. INTEM CHECK OR MAINTENANCE JOB 1 6 12 18 24 CHECK

1 * Fuel line • Check fuel hoses and vacuum hose for cracks

√ √ √ √ √

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

• Replace. √ √

3 Air filter element • Clean. √ √

• Replace. √ √

4 * Front brake • Check operation, fluid level and vehicle for√ √ √ √ √ √fluid leakage.

• Replace brake pads. Whenever worn to the limit

5 * Rear brake • Check operation and adjust brake lever freeplay. √ √ √ √ √ √

• Replace brake shoes. Whenever worn to the limit

6 * Brake hose • Check for cracks or damage. √ √ √ √ √

• Replace. (See NOTE on page 6-5) Every 4 years

7 * Wheels • Check runout and for damage. √ √ √ √

8 * Tires • Check tread depth and for damage.• Replace if necessary.

√ √ √ √• Check air pressure.• Correct if necessary.

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

10 * Steering bearings • Check bearing play and steering for roughness. √ √ √ √ √

• Lubricate with lithium-soap-based grease. Every 24.000 km

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

12 Centerstand • Check operation. √ √ √ √ √

• Lubricate.

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

14 * Rear shock absorber • Check operation and shock absorber for oil√ √ √ √assembly leakage.

15 * Carburetor • Check starter (choke) operation.√ √ √ √ √ √

• Adjust engine idling speed.

16 * Autolube pump • Check operation.√ √ √ √

• Bleed if necessary.

17 Final gear oil • Check oil level and vehicle for oil leakage. √ √ √

• Change. √ √ √

18 * V-belt • Replace √ √

19 Front and rear brake • Check operation.√ √ √ √ √ √switches

20 * Moving parts • Lubricate. √ √ √ √ √and cables

21 Lights, signals • Check operation.√ √ √ √ √ √and switches • Adjust headlight beam.

• Since these items require special tools, data and technical skills, have a Yamaha/MBK dealer perform the ser-vice.

NOTE:

• The air filter needs more frequent service if you are riding in unusually wet or dusty areas.• Hydraulic brake service•• Regularly check and, if necessary, correct the brake fluid level. •• Every two years replace the internal components of the brake master cylinder and caliper, and change the brake fluid.•• Replace the brake hoses every four years and if cracked or damaged.

INSPADJREAR BODYWORK AND FOOTREST

3-2

REAR BODYWORK AND FOO-TRESTREMOVAL1. Raise the seat2. Remove:

• Seat

3. Remove:• Battery cover

4. Remove:• Rear cover

5. Remove:• Side covers

NOTE:

When the side covers are being removedunhook them from the catches and slidethem outwards.

INSPADJREAR BODYWORK AND FOOTREST

3-3

6. Remove:• Footrest

INSTALLATIONWhen the foot support panel and the rearcover are being installed, reverse the removalprocess.Remember the following points.

1. Install:• Side covers

NOTE:

• Match up the support and hole and thenapply pressure.

INSPADJREAR BODYWORK, MUDGUARDS

3-4

REAR BODYWORK, MUD-GUARDSREMOVAL1. Remove:

• Main switch cover. Turn the cover to the left and pullupwards.

2. Remove:• Upper screws in ignition key panel• Rear fairing assembly and headlight

NOTE:

Disconnect the headlight cable and indica-tors.

3. Remove:• Front lower fairing screws • Carrier hook bolt • Footrest lower cover screws

4. Remove:• Battery cover• Battery, fuse and starter relay• Bottom footrest cover• Footrest• Bottom rear fairing

NOTE:

Disconnect indicator cables.

• Mudguards

INSTALLATIONReverse the removal process.

NOTE:

After installing all plastic parts, check that allhooks are properly attached.

INSPADJHANDLEBAR COVERS

3-5

HANDLEBAR COVERSREMOVAL1. Remove:

• Front handlebar cover • Rear handlebar cover

INSTALLATIONReverse the removal procedure. Rememberthe following points.1. Install:

• Front handlebar cover • Rear handlebar cover

NOTE:

When installing the rear cover, check that thespeedometer cables goes through its hou-sing.

NOTE:

After installing the handlebar cover, ensurethat all the hooks are properly coupled.

INSPADJADJUSTMENT OF ENGINE IDLING

3-6

ENGINEADJUSTMENT OF ENGINE IDLING1. Tighten:

• Pilot air screw Turn the pilot air screw inwards until itseats itself lightly.

2. Loosen:• Pilot air screw.

Unscrew it from its lightly seated posi-tion.

3. Start the engine and let it warm up.

ss WARNING

Before starting the engine, ensure that thecentral safety stand is being used.

4. Join:• Inductive tachometer

On the spark plug cable

5. Check:• Engine idling.

Outside specified value Adjust.

6. Adjust:• Engine idling

Adjustment steps:• Turn the accelerator stop screw outward

or inwards until the specified idling is obtai-ned.

OUTWARDS TURNS OF THE PILOT AIR SCREW:

DELLORTO GURTNER

EU0 EU1 EU0 EU1 MOFA

1 1/2±14 2 1/8±1/8 1 1/8 1 7/8 1 7/8

Inductive tachometer90890-03113

Engine idling1.800 rpm

Turn inwards Increases idling.Turn outwards Decreases idling.

INSPADJ

AJUSTE DEL JUEGO LIBRE DELCABLE DEL ACELERADOR

3-7

ADJUSTMENT OF FREE PLAY OF THROT-TLE CABLE1. Check:

• Free play of throttle cable aOutside specified value Adjust.

Steps for adjusting the free play of thethrottle cable:

NOTE:

Before adjusting the free play of the throttle,engine idling should be adjusted.

First step:• Loosen the lock nut of the throttle cable.• Turn the adjuster inwards or outwards

until the specified free play is obtained.

• Tighten the lock nuts.

NOTE:

If the free play cannot be adjusted, adjust thecable on the side of the carburettor (secondstep).

Second step:• Remove the cover.• Loosen the lock nut .• Turn the adjuster inwards or outwards

until the specified free play is obtained.

• Tighten the lock nut.• Install the cover.

ss WARNING

After adjustment, turn the handlebar to theright and left and check that the idling doesnot vary.

Free play2 ~ 5 mm

Turn inwards Free play increases.Turn outwards Free play decreases.

Turn inwards Free play increases.Turn outwards Free play decreases.

INSPADJSPARK PLUG INSPECTION

3-8

SPARK PLUG INSPECTION 1. Inspect:

• Incorrect type of spark plug Replace

2. Inspect:• Electrode

Worn/Damaged Replace• Insulator

Abnormal colour Replace The normal colour is a light to mediumcoffee colour.

3. Clean the spark plug with a spark plug cle-aner or wire brush.

4. Measure:• Distance between electrodes

Use a thickness gauge. Outside the specified value Correct

5. Tighten:• Spark plug

Gap between electrodes0.6 ~ 0.7 mm

Spark plug2.0 m • kg

Standard spark plug (5AD y SA15)BR8HS/N.G.K.

for SA19BRP4HS/N.G.K.

INSPADJINSPECTION OF ENGINE OIL LEVEL

3-9

INSPECTION OF ENGINE OILLEVEL1. Inspect:

• Engine oil level Low oil level Add sufficient oil.

Oil indicator light “OIL CAUTION”

NOTE:

After filling the oil tank, replace the cap andclose the seat.

Recommended oil:JASO grade FC 2 stroke

engine oil or equivalentTotal:

1.2 L

Visual inspection steps for engine oil level

Place main switch in position (h)

The “OIL CAUTION” indicator light is not lit.

Inspect for defective electric circuit, bulbs, etc.

The “OIL CAUTION” indicator light is lit.

Place the main switch inposition “f”


The “OIL CAUTION” indicator light is lit.

Supply engine oil.


The engine oil level andelectric circuit are ingood condition.

INSPADJ

CHANGE OF TRANSMISSION OIL / CLEANING AIR FILTER

3-10

CHANGE OF TRANSMISSION OIL1. Remove:

• Drainage bolt Drain the transmission oil.

• Oil refill cap 2. Inspect:

• Gasket (drainage screw)• O-ring (refill cap)

Damaged Change

3. Install:• Gasket• Drainage screw

4. Fill:• Transmission Case

CLEANING AIR FILTERCarburettor side1. Remove:

• Air filter box assembly

Drainage screw18 Nm (1.8 m • kg)

Transmission oilSE engine oil type SAE 30 or GLgear oil

Caacity:0.11 L

4

2

INSPADJCLEANING AIR FILTER

3-11

2. Remove:• Air filter box • Air filter

ATTENTION:

Never start up the engine with the air filterremoved. This will allow the entry of unfilte-red air, causing rapid wear and possibledamage to the engine. Also, using the engi-ne without the filter will affect the carburet-tor jets resulting in poor performance andthe possible overheating of the engine.Be careful not to block the inlet area of theair filter with cloths or rags.

3. Inspect:• Damaged element Change

4. Clean:• Air filter

Steps for cleaning air filter:• Wash the filter carefully but completely with

solvent.

ss WARNING

Never use solvents with a low flammabilitypoint, such as petrol, to clean the filter.Such solvents may cause fire or explosions.

• Clean off excess solvent from the filter andleave it to dry.

ATTENTION:

Do not wring the filter when drying it.

• Apply oil for foam air filters or YAMAHA 2Tengine oil or equivalent oil for 2 stroke air-cooled engines.

• Wipe off the excess oil.

NOTE:

The filter should be wet but not dripping.

INSPADJ

ADJUSTMENT OF FREE PLAY OF FRONT BRAKE LEVER /ADJUSTMENT OF FREE PLAY OF REAR BRAKE LEVER /

INSPECTION OF BRAKE PADS

3-12

CHASSISADJUSTMENT OF FREE PLAY OF FRONTBRAKE LEVER1. Check:

• Free play of the front brake lever.

ss WARNING

The soft or spongy feeling of the brake levermay indicate the presence of air in thebrake system. This air should be extractedby bleeding the brake system before usingthe vehicle. Air in the system will reduce thebraking capacity and may cause loss ofcontrol and accidents. Inspect and bleedthe system if it is necessary.

ADJUSTMENT OF FREE PLAY OF REARBRAKE LEVER1. Check.

• Free play of rear brake lever aOutside specified value Adjust

Steps for adjusting the free play of the rearbrake lever:• Turn the adjuster inwards or outwards

until the correct free play is obtained.

INSPECTION OF BRAKE PADS1. Activate the front brake lever2. Inspect:

• Brake pads. Wear indicator almost contacts withthe brake disc Replace the set ofbrake pads.See “CHANGE OF BRAKE PADS” sec-tion in chapter 6.

5 ~ 10 mm

2 ~ 5 mm

INSPADJ

INSPECTION OF BRAKE SHOES /INSPECTION OF BRAKE FLUID LEVEL

3-13

NSPECTION OF BRAKE SHOES1. Activate the brake lever2. Inspect:

• Wear indicator Indicator on wear limit line Changethe brake shoes.

INSPECTION OF BRAKE FLUID LEVEL

NOTE:

Place the scooter upright when inspecting thefluid level.

1. Inspect:• Fluid level.

The fluid level is below the minimumlevel line Refill up to correct level.

ATTENTION:

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

ss WARNING:

• Only use fluid of the designated quality.Otherwise the rubber seals may deterio-rate due to leakages and poor performan-ce of the brakes.

• Refill with the same type of fluid. The mix-ture of fluids may cause a damaging che-mical reaction which may cause the poorperformance of the brakes.

• Take care not to let water enter the pumpwhile it is being filled. The water will lowerthe boiling point of the fluid significantlyand may cause a steam blockage.

Recommended fluid:DOT 4

INSPADJ

AIR BLEEDING (HYDRAULIC BRAKE SYSTEM) /STEERING ADJUSTMENT

3-14

AIR BLEEDING (HYDRAULIC BRAKE SYS-TEM)1. Bleed:

• Brake fluid

Steps for air bleeding:a. Add the appropriate amount of brake fluid

to the sump.b. Install the diaphragm. Take care not to spill

fluid or to let the sump overflow.c. Connect the clean plastic tube .d. Place the other end of the tube in a contai-

ner.e. Slowly apply the brake lever several times.f. Pull the lever inwards. Keep it in this posi-

tion.g. Loosen the bleed screw and tighten the

lever as far as it will go.h. Tighten the bleed screw when it has rea-

ched its limit, afterwards loosen the lever.i. Repeat steps (e) to (h) until the air bubbles

in the system have been removed.j. Add brake fluid to the correct level.

ss WARNING

Check the brake operation after bleedingthe system.

STEERING ADJUSTMENT1. Check:

• Steering assembly bearings Press downthe bottom of the fork and carefullymove the assembly forwards and back-wards. Loose Adjust

INSPADJINSPECTION OF TYRES

3-15

Steps for tightening the steering nut:1. Tighten the lower ring to 3.8 m • kg.2. Loosen the lower ring nut 1/2 of a turn

and tighten to 0.65 m • kg.3. Check the steering for smooth operation.4. Install rubber washer .5. Install central ring nut and hand tighten

untill the lower and central ring nuts slotsallignet.

6. Install the lock washer .7. Supporting the lower and central ring nuts,

install and thigten the upper ring nut to 7.5 m • kg.

INSPECTION OF TYRES

ss WARNING

• Do not try to use tubeless tyres in a wheeldesigned only for inner tube tyres. Thismay cause damage to the tyre and perso-nal injury due to a puncture.

1. Measure:• Air pressure

Outside specified value Adjust

2. Inspect:• Tyre surface

Worn/Damaged Change

Thread depth Side wall Wear indicator

Wheel TyreTube type Only imer tube type

tubeless type With or without tube type

Basic weight:

With oil sump and fuel

tank full 87 kg

Maximum load* 155

Cold tyre front Rear

pressure 1.75kg/cm2 2.00 kg/cm2

Minimum depth of thread of tyres0.8 mm

INSPADJ

WHEEL INSPECTION / INSPECTION OF REAR FORK /REAR SHOCK ABSORBER INSPECTION

3-16

WHEEL INSPECTION1. Inspect:

• Wheels damaged/warped Replace.

ss WARNING:

Never try to make even the smallestrepairs on wheels.

INSPECTION OF REAR FORK1. Inspect:

• Rear fork Bent/Damaged Fork bar Change Oil leaks Seals Change Rough operation Fork assembly

Change

REAR SHOCK ABSORBER INSPECTION1. Inspect:

• Rear shock absorberOil leaks/Damage Replace

2. Check• Coupling torque

Upper(nut) 3.2 m • kg

Lower(bolt) 1.8 m • kg

INSPADJBATTERY INSPECTION

3-17

ELECTRICAL SYSTEMBATTERY INSPECTION1. Remove:

• Battery cover See “REAR BODYWORK” section

2. Inspect:The fluid level between the maximum and minimum marks. Incorrect Refill

ATTENTION:

Add only distilled water; tap water containsminerals which are damaging to the battery.

3. Inspect:• Battery terminals

Dirty terminals Clean with a wirebrush Bad connection Correct

NOTE:

Once the terminals are clean, apply a thincover of grease.

4. Check:• The density of the electrolyte

Less than 1,280 Recharge the battery

Charge current:0.3 Amps/10 Hrs

Electrolyte density:1,280 at 20 °C (68 °F)

INSPADJBATTERY INSPECTION

3-18

Change the battery in the following cases:• When the voltage does not reach the speci-

fied value and bubbles do not appear, evenafter several hours of charging.

• When one or more of the trays becomesulphated, which can be seen when theplates become white are material accumu-lates on the bottom.

• When the density readings after slow char-ging over a prolonged period, indicate thatone of the trays is lower than the other.

• When the warping or ondulation of one ofthe plates or insulators is evident.

ATTENTION:

Always charge new batteries beforeassembling them, in order to guaranteemaximum performance.

ss WARNING

The electrolyse in the battery is dangerous;it contains sulphuric acid and is conse-quently poisonous and very caustic.Always follow the following preventivemeasures:• Avoid physical contact with the electroly-

te which can cause serious burns or per-manent damage to sight.

• Use protective glasses when handlingbatteries or working near them. Antidote(EXTERNAL):

• SKIN - Wash with water.• EYES - Wash with water for 15 minutes

and consult a doctor immediately.Antidote (INTERNAL):• Drink large quantities of water or milk,

followed by milk of magnesia, beaten eggof vegetable oil.

• See a doctor immediately.Batteries also generate explosive hydrogengas, so that the following preventive mea-sures should always be observed:• Charge the batteries in a well ventilated

area.• Maintain the batteries away from fire,

sparks or flames (for example, solderingequipment, lit cigarettes, etc.).

• DO NOT SMOKE while batteries are beingcharged or handled.

MAINTAIN BATTERIES AND THE ELEC-TROLYSE OUT OF THE REACH OF CHIL-DREN.

INSPADJINSPECTION OF FUSES

3-19

INSPECTION OF FUSES1. Remove:

• The battery cover See the “FRONT BODYWORK” section

2. Inspect:• Fuse

Defective Replace

Steps to be taken for blown fuses:• Disconnect the ignition and circuit.• Install a new fuse of the correct amperage.• Connect the switches to check the correct

operation of the electrical device.• If the fuse blows immediately after, check

the circuit concerned.

ss WARNING

Do not use fuses of a higher amperage thanthat recommended. This can cause extensi-ve damage to the electrical system and fire.

Description Amperage QuantityPrincipal 7A 1

INSPADJ

ADJUSTMENT OF HEADLAMP BEAM /REPLACEMENT OF HEADLAMP BULB

3-20

ADJUSTMENT OF HEADLAMP BEAM1. Adjust:

• Headlamp (vertically)

REPLACEMENT OF HEADLAMP BULB1. Remove:

• Front fairing2. Disconnect

• Headlamp cables

3. Remove:• Headlamp bulb cover• Headlamp bulb

4. Install:When the front fairing is installed, reversethe removal process

To raise the beam

Turn the screw inwardsTo lower the beam

Turn the screw outwards

CHAPTER 4GENERAL OVERHAUL OF ENGINE

ENGINE REMOVAL ………………………………………………………………4-1REAR COVER AND FOOTREST PANEL ……………………………………4-1CARBURETTOR ………………………………………………………………4-1SILENCER ASSEMBLY ………………………………………………………4-1CABLES AND TUBES …………………………………………………………4-2REMOVAL OF ENGINE ………………………………………………………4-3

DISASSEMBLY THE ENGINE …………………………………………………4-4REAR WHEEL …………………………………………………………………4-4CENTRAL SUPPORT …………………………………………………………4-4CYLINDER HEAD AND CYLINDERS ………………………………………4-4PISTON PINS AND PISTON …………………………………………………4-4KICK STARTER…………………………………………………………………4-5PRIMARY PULLEY WHEEL …………………………………………………4-6SECONDARY PULLEY WHEEL………………………………………………4-6STARTER SYSTEM ……………………………………………………………4-7TRANSMISSION ………………………………………………………………4-8MAGNETIC FLYWHEEL ………………………………………………………4-8AUTOLUBRICATION PUMP …………………………………………………4-9CRANKCASE AND CRANKSHAFT …………………………………………4-9

INSPECTION AND REPAIR……………………………………………………4-11CYLINDER HEAD ……………………………………………………………4-11CYLINDER AND PISTON ……………………………………………………4-11PISTON RINGS ………………………………………………………………4-13PISTON PIN AND PISTON PIN BEARING ………………………………4-14KICK STARTER ………………………………………………………………4-15TRANSMISSION………………………………………………………………4-16AUTOLUBRICATION PUMP…………………………………………………4-16CRANKSHAFT ………………………………………………………………4-16PRIMARY PULLEY WHEEL …………………………………………………4-17SECONDARY PULLEY WHEEL ……………………………………………4-18TRAPEZOIDAL BELT…………………………………………………………4-19GEARS AND STARTER CLUTCH …………………………………………4-19

ASSEMBLY AND ADJUSTMENT OF ENGINE ……………………………4-21CRANKSHAFT AND CRANKCASE…………………………………………4-21AUTOLUBRICATION PUMP…………………………………………………4-23FLYWHEEL MAGNET ………………………………………………………4-24TRANSMISSION………………………………………………………………4-25STARTER MOTOR ……………………………………………………………4-27SECONDARY PULLEY WHEEL ……………………………………………4-29PRIMARY PULLEY WHEEL …………………………………………………4-29STARTER PEDAL ……………………………………………………………4-30PISTON AND PISTON PIN …………………………………………………4-35CYLINDER AND HEAD ……………………………………………………4-36ENGINE ASSEMBLY …………………………………………………………4-38

ENG

ENGENGINE REMOVAL

4-1

GENERAL OVERHAUL OFTHE ENGINEREMOVAL OF ENGINEREAR BODYWORK AND FOOTREST1. Remove:

• Side covers (left and right)• Rear cover• Footrest panel See section in chapter 3

“REAR BODYWORK AND FOOTREST”

CARBURETTOR1. Remove:

• Air filter box assembly

2. Disconnect:• Autochoke wire • Trhottle cable

3. Remove:• Oil discharge tube • Fuel supply tube• Carburettor

SILENCER ASSEMBLY1. Remove:

• Silencer assembly • Ventilator cover

2. Loosen:• Rear axle nut

NOTE:

When the rear wheel axle nut is loosened,apply the rear brake.

1

1

1

ENGENGINE REMOVAL

4-2

CABLES AND PIPES1. Remove:

• Oil pipe from side of oil pump.

NOTE:

Position oil pipe so that the oil does not spillout.

2. Remove:• Bolts (trunk)• Overflow bowl rivets

NOTE:

To remove the overflow bowl, take off the fueland oil caps and replace them immediatelyafter removing the bowl.

3. Disconnect:• Battery cable • Starter motor cable • Magnetic flywheel cable • Spark plug pipe

4. Remove:• Rear brake cable

1

ENGENGINE REMOVAL

4-3

ENGINE REMOVAL1. Remove:

• Rear shock absorber screw (lower)

2. Remove:• Engine assembly screw • Engine Lift the frame and remove theengine

3. Place the frame on a suitable support

ENGDISASSEMBLY THE ENGINE

4-4

DISASSEMBLY ENGINEREAR WHEEL1. Remove:

• Rear wheel• Brake shoes • Flat washer

CENTRAL STAND1. Remove:

• Clip • Rubber washer • Axle• Clasp • Spring • Central stand

CYLINDER HEAD AND CYLINDER1. Remove:

• Cover• Cylinder head • Cylinder head gasket

NOTE:

• Before loosening the cylinder head, loosenthe spark plug .

• The position nuts of the cylinder headshould be loosened by 1/2 a turn each timeand then removed.

2. Remove:• Cylinder • Cylinder gasket

PISTON PIN AND PISTON1. Remove:

• Piston pin clip

NOTE:

Before removing the piston pin clip, cover thecrankcase with a clean cloth so that it doesnot accidentally fall into the crankcase.


4-5

2. Remove:• Piston pin • Piston • Piston pin bearing

ATTENTION:

Do not use a hammer to take out the pis-ton pin.

KICKSTART SYSTEM1. Remove:

• Kickstart pedal• Crankcase cover (left)

2. Remove:• Guide(air filter)• Air filter

3. Remove:• Pedal gear

NOTE:

When the pedal gear removed, move thepedal axle.

4. Unhook:• Return spring

5. Remove:• Circlip • Flat washer • Pedal axle


4-6

PRIMARY PULLEY WHEEL1. Remove:

• Fan2. Remove:

• Nut (primary pulley wheel)

NOTE:

When the nut is loosened (primary pulleywheel), support the magnetic flywheel usingthe engine wheel support tool

3. Remove:• Conical spring washer • One-way clutch • Washer • Fixed primary pulley wheel • Shim • Trapezoidal belt

4. Remove:• Hub • Primary pulley wheel assembly

SECONDARY PULLEY WHEEL1. Remove:

• Nut (secondary pulley wheel)

NOTE:

Support the secondary pulley wheel using thepulley wheel clamp .

2. Remove:• Clutch drum • Secondary pulley wheel assembly • Crankcase cover gasket• Centring devices

Engine wheel holding tool:90890-01235

Pulley wheel clamp:90890-01701


4-7

3. Apply:• Pulley wheel clamp • Nut spanner (41MM)

4. Loosen:• Clutch positioning nut

ATTENTION:

Do not remove the clutch positioning nutyet.

5. Apply:• Clutch spring compressor

6. Remove:• Clutch positioning nut

7. Remove:• Clutch assembly • Clutch spring • Spring seat • Guide pins• Secondary sliding pulley wheel

STARTER SYSTEM1. Remove:

• Plate (intermediate gearing)• Intermediate gearing • Starter clutch assembly • Washer• Starter wheel gearing

2. Remove:• Bushing • Bearing • Washer • Starter motor

Pulley wheel clamp:90890-01701

Clutch spring compressor:90890-01337


4-8

TRANSMISSION1. Remove:

• Transmission box cover • Gasket • Centring devices

NOTE:

Before proceeding to disassemble the trans-mission cap, empty the oil.

2. Remove:• Main axle • Drive axle • Flat washer • Conical spring washer

3. Remove:• Oil seal • Bearing • Secondary pulley wheel axle

MAGNETIC FLYWHEEL1. Remove:

• Nut (rotor)• Flat washer

NOTE:

Support the rotor to loosen the nut with theengine flywheel support tool .

2. Remove:• Rotor • Woodruff key

Use the magnetic flywheel extractor

• Stator assembly• Gasket

Magnetic flywheel extractor90890-01362

Engine flywheel support tool90890-01235


4-9

AUTOLUBRICATION PUMP1. Remove:

• Autolubrication pump

2. Remove:• Elastic circlip • Pump drive gearing • Pin • Elastic circlip

3. Remove:• Carburettor gasket • Reed valve• Reed valve gasket

CRANKCASE AND CRANKSHAFT1. Remove:

• Oil seal catch • Screws (crankcase)

NOTE:

Loosen each screw 1/4 of a turn and removethem after loosening them.

2. Apply:• Crankcase separation tool

NOTE:

Fully tighten the positioning nuts of the tool,but ensure that the tool body is parallel withthe box. If necessary, slightly loosen one ofthe screws to level the body of the tool.

Crankcase separation tool90890-01135


4-10

3. Remove:• Crankcase (right)

While pressure is applied, strike alternati-vely on the engine assembly hubs.

4. Apply:• Crankcase separation tool

5. Remove:• Crankshaft

Crankcase separation tool90890-01135

ENGINSPECTION AND REPAIR

4-11

INSPECTION AND REPAIRCYLINDER HEAD1. Eliminate:

• Carbon deposits Use a rounded scraper

2. Inspect:• Cylinder head warping.

Outside specified value Rectify

Steps for measuring warping and rectifica-tion:• Join a straight edge and a thickness cali-

bration on the cylinder head• Measure the limit of the warping

• If the warping is outside the specified value,rectify the cylinder head

NOTE:

Turn the cylinder head several times to avoidremoving too much material from one side

CYLINDER AND PISTON1. Eliminate:

• Carbon deposits Use a rounded file 2. Inspect:

• Cylinder wall Wear/striping Rectify orchange

3. Eliminate:• Carbon deposits

From the piston crown and ring grooves.

Warping limit0.02 mm


4-12

4. Remove:• Cracking marks and carbon deposits on

piston sides.5. Inspect:

• Piston wall Wear/striping/damage Change

6. Measure:• Cylinder piston clearance

Steps for measuring the clearance of thecylinder pistonFirst step:• Measure the lower diameter “C” with a dial

gauge.

NOTE:

Measure the inner diameter of cylinder “C” inparallel and at right angles to the crankshaft.Then find the mean of the measurements.

• If this is outside the specified value, rectifyor change the cylinder, change the piston andthe set of rings.

Second step:• Measure the diameter of the piston skirt “P”

with a micrometer.a 5.0 mm (0.20 in) from the inner edge ofthe piston

WearStandard limit

Inner diameter40.0 mm 40.10 mmof cylinder “C”

Taper– 0.05 mm“T”

Eccentricity– 0.01 mm“R”

“C” = Maximum D“T” = (Maximum D1 o D2) - (Maximum D5

or D6)“R” = (Maximum D1 D3 o D5) -

(Maximum D2 D4 o D6)


4-13

• If this is outside the specified value changethe piston and the set of rings.

Third step:• Calculate the clearance of the piston to the

cylinder using the following formula:

• If this is outside the specified value, rectifyor change the cylinder and change the pis-ton and set of rings.

PISTON RINGS1. Measurement:

• Lateral clearance Outside specified value Change the piston and/or rings. Usea thickness gauge .

2. Install:• Piston rings on the cylinder

Press the ring and the piston crowntogether.

Size of the piston P

Standard 39.952 ~ 39.997 mm1st Clearance 40.25 mm2st Clearance 40.50 mm

Clearance of piston to cylinder =Inner diameter of cylinder “C” –Diameter of piston skirt “P”

Cylinder-piston clearance0.034 ~ 0.047 mm

Limit0.1 mm

Standard Limit

Top ring 0.03~0.05 mm 0.10 mm

Second ring 0.03~0.05 mm 0.10 mm


4-14

3. Measure:• Gap between ends

Outside specified value Change setof rings. Use a thickness gauge .

a Measurement point 20 mm (0.8 in)

4. Clearance of piston rings:The size of the rings is not stamped on itsupper part.

PISTON PIN AND PISTON PIN BEARING1. Inspect:

Piston pinBlue discolouring/Groove Change, theninspect the lubrication system.

2. Measure:• External diameter a (Piston pin clip)

Outside specified value Change

3. Measure:• Clearance of piston pin to piston:

Outside specified value Change thepiston

Clearance of piston pin to piston0.004 ~ 0.016 mm

Limit0.07 mm

Standard Limit

Top ring 0.15~0.35 mm 0.60 mm

Second ring 0.15~0.35 mm 0.60 mm

Clearance of piston pin to piston=Size of inner diameter (Piston pin) b -External diameter (piston pin housing) a

External diameter (piston pin clip)9.996 ~ 10.00 mm

Piston ring clearance1st Clearance 40.25 mm2st Clearance 40.50 mm


4-15

4. Inspect:Bearing (piston pin)Pitting/Damage Change

KICKSTART1. Inspect:

• Pedal gear teeth • Pedal pinion gear teeth

Burrs/Spalling/Non-uniformity/Wear

Change

2. Inspect:• Locking bolt(pedal pinion gear and one

way clutch) Rounded edges/Wear Change

3. Measure:• Spring tension (pedal pinion gear)

Outside specified value Change Use a dynamometer

Standard tension150 ~ 250 gr


4-16

TRANSMISSION1. Inspect:

• Drive axle • Main axle • Secondary pulley wheel axle


Change

2. Inspect:• Secondary pulley wheel axle bearing • Main axle bearing • Drive axle bearing

Pivot the inner guide of the bearing.Excessive play/Non-uniformity

Change Pitting/Damage Change

AUTOLUBRICATION PUMPInternal wear or poor operation may causethe pump to deviate from its factory adjust-ment. However, this is very uncommon. Ifincorrect operation is suspected, inspect thefollowing:1. Inspect:

• Supply line Obstruction Apply airunder pressure

• O-ring Wear/Damage Change2. Inspect:

• Drive gear teeth of the autolubricationpump • Gear teeth driven by autolubrication

pump Pitting/Wear/Damage

Change

CRANKSHAFT1. Measurement:

• Deflection limit “C”• Clearance on big end side “D”• Limit of free play at small end of connec-

ting rod “F” Outside specified value Change. Use V blocks, dial gauges and thicknessgauge.


4-17

2. Inspect:• Bearings (crankshaft) Pivot the inner bea-

ring guide. Excessive play/Non-uniformity

ChangePitting/Damage Change

PRIMARY PULLEY WHEEL1. Inspect:

• Primary sliding pulley wheel • Primary fixed pulley wheel

Wear/Cracks/Striping/Damage

Change

2. Check:• Free movement Insert the bushing in the

primary sliding pulley wheel and check ifthere is free movement. If it catches or there is excessive play

Change the pulley wheel or the bushing.

3. Measure:• External diameter (roller)

Outside specified value Change.

External diameter (roller)15.0 mm

Limit:14,5 mm

Deflection limit “C”:0.03 mm

Clearance on big end side “D”:0.2 ~ 0.5 mm

Free play at small end “F”:0.4 ~ 0.8 mm


4-18

SECONDARY PULLEY WHEEL1. Inspect:

• Secondary fixed pulley wheel • Secondary sliding pulley wheel

Striping/Cracks/Damage Change set.• Oil seal

Damage Change.

2. Inspect:• Turning cam groove • Guide pin

Wear/Damage Change set.• O-ring

Damaged Change.

3. Measure:• Free length of variator spring.


4. Inspect:• Inner surface of the clutch hub

Oil/Striping Clean

5. Measure:• Internal diameter of the clutch hub a


Free length of secondary pulleywheel

109.6 mm<Limit>

90.4 mm

Oil Use a cloth dampened withdissolvent

Striping Use sand paper (polish lightlyand uniformly)

Internal diameter of clutch hub105.0 mm

<Wear limit>105.4 mm


4-19

6. Inspect:• Clutch shoes shiny parts Polish with

sand paper.

NOTE:

After using sand paper, clean the polishedparticles with a cloth.

7. Measure:• Thickness of clutch shoe a


TRAPEZOIDAL BELT1. Inspect:

• Trapezoidal beltCracks/Wear Change

NOTE:

Replace the trapezoidal belt if it is dirty withoil or grease.

2. Measure:• Width of trapezoidal belt a


STARTER CLUTCH AND GEARS1. Inspect:

• Starter clutch Press the conical pin in thedirection of the arrow. Rough operation Change the starterclutch assembly

Width of trapezoidal belt16.5 mm

<Wear limit>15.7 mm

Thickness of clutch shoe2.0 mm

<Wear limit>1.0 mm


4-20

2. Inspect:• Starter wheel gear teeth • Intermediate gear teeth


Change• Bearing (starter wheel gear)

Pitting/Damage Change

ENGASSEMBLY AND ADJUSTMENT OF ENGINE

4-21

ASSEMBLY AND ADJUSTMENT OF ENGINECRANKSHAFT AND CRAKCASE

Oil seal Oil seal catch Crankcase (right) Centring device Bearing Crankcase (right) Bearing

Crankshaft pin Connecting rod10 Crankcase (left)11 Bearing12 Engine mounting spacer13 Crankcase (left)14 Oil seal

CRANKSHAFT

A: 37.90 ~ 37.95 mm

C: 0.03 mmD: 0.2 ~ 0.5 mmF: <Limit> 1.0 mm

0.4 ~ 0.8 mm

MOTASSEMBLY AND ADJUSTMENT OF ENGINE

4-22

CRANKSHAFT AND CRANKCASE

1. Place:• Crankshaft installation tool

2. Install:• Crankshaft

(in left crankcase)3. Install:

• Centring device• Engine mounting spacer

4. Apply:• Yamaha N.º 1215 adhesive on the

corresponding surfaces of both halves ofthe crankcase

5. Place:• Crankshaft installation tool

6. Install:• Right crankcase

7. Tighten:• Crankcase positioning screws

NOTE:

Tighten the crankcase positioning screws instages, using a crossed method for tighte-ning.

8. Check:• Rotation of crankshaft

Rough turning Repair9. Install:

• Oil seal catch plate

Crankshaft installation tool:: 90890-01411: 90890-01274: 90890-01275: 90890-01277

Yamaha N. 1215 adhesive:90890-85505

Crankshaft installation tool:: 90890-01411: 90890-01274: 90890-01275: 90890-01277

Crankcase screws0.9 m • kg

Screw (oil seal catch plate)0.9 m • kg


4-23

Fan Flat washer Rotor assembly Charge coil Lighting coil Harnessing coil Stator plate Oil seal Gasket

10 Oil outlet pipe11 Oil pipe12 Bushing13 Autolubrication pump14 O-ring15 Elastic circlip16 Oil pump drive gear17 Pin

AUTOLUBRICATION PUMP AND MAGNETIC FLYWHEEL


4-24

AUTOLUBRICATION PUMP1. Install:

• Elastic circlip • Pin • Pump drive gear • Elastic circlip

2. Apply:• Grease with lithium soap base

(on the o-ring )3. Install:

• Autolubrication pump


(on the autolubrication pump gear , )

FLYWHEEL MAGNETO1. Install:

• Seal2. Apply:

• Grease with lithium soap base (on the oil reten )

3. Pass the wheel cable through the crankca-se orifice.

4. Install:• Stator assembly

5. Install:• Key• Magnetic wheel• Flat washer• Nut

Screw (autolubrication pump)0.4 m • kg

15 cc

Screw (stator assembly)0.8 m • kg


4-25

TRANSMISSION

Circlip Bearing Oil seal Drive axle Bearing Main axle Conical spring washer Flat washer

Secondary pulley wheel axle10 Bearing11 Centring device12 Seal13 Transmission box cover14 Bearing15 Oil seal


4-26

6. Tighten:• Nut (flywheel magneto)

Use the engine wheel support tool .

TRANSMISSION1. Apply:

• SE engine oil type 10W30(on the transmission box cover bearing)

2. Install:• Secondary pulley wheel axle

(on transmission box cover)3. Install:

• Circlip • Oil seal

NOTE:

Apply grease with lithium soap based on theoil seal lips.

4. Check:• Rotation of secondary pulley wheel axle.

Rough rotation Repair.

5. Apply:• SE type 10W30 engine oil

(on bearing of main axle and drive axlebearing)

6. Install:• Drive axle • Main axle• Conical spring washer • Flat washer

7. Install:• Gasket• Conical pins• Transmission box cover

Screw (box cover)0.9 m • kg

Flywheel nut4.3 m • kg

Engine wheel support tool90890-01235


4-27

STARTER SYSTEM

Bushing Bearing Starter wheel gear Starter clutch Plate

Axle Flat washer Intermediate gear O-ring10 Starter engine


4-28

STARTER SYSTEM1. Install:

• Bushing • Bearing • Starter wheel gear • Starter clutch

NOTE:

• Apply grease with a lithium soap base onthe bearing .

• Apply molybdenum disulphide oil on the pin (starter clutch) .

2. Install:• Flat washer • Intermediate gear • Flat washer • Plate (intermediate gear)

NOTE:

Apply engine oil on the intermediate gear .

3. Install:• Starter motor

NOTE:

Apply grease with a lithium soap base on theo-ring of the starter motor.

Screw (intermediate gear plate)0,8 m • kg

Starter motor bolts1,3 m • kg


4-29

SECONDARY AND PRIMARY PULLEY WHEEL

Nut Clutch drum Clutch plate Shoe spring Clutch spring Spring seat Oil seal O-ring

Secondary sliding pulleywheel

10 Trapezoidal belt11 Guide pin12 Secondary fixed pulley wheel13 Conical washer14 One-way clutch15 Washer16 Fixed primary pulley wheel

17 Shim18 Hub19 Sliding primary pulley wheel20 Rollers21 Runner22 Cam23 Washer

*: Apply assembly lube

FREE LENGTH LIMIT OF VARIATOR:83 mm

WASTE LIMIT OF CLUTCH HOUSING:107.4 mm

WASTE LIMIT OF CLUTCH SHOES:1.0 mm

TRAPEZOIDAL BELT WASTE LIMIT:15.7 mm

VARIATOR ROLLER LIMIT:14.5 mm


4-30

KICKSTART PEDAL

Pedal axle Return spring Bushing Flat washer Elastic retainer Starter pedal Spring Pedal pinion gear

10 Nm (1.0 m • kg)

150 ~ 250 g


4-31

SECONDARY PULLEY WHEELWhen assembling the secondary pulleywheel, reverse the disassembly procedure.Remember the following points:1. Apply:

• Assembly grease(in the sliding/fixed pulley wheel)

2. Install:• Sliding pulley wheel

NOTE:

Take care that the lips of the oil seals do notturn when the pulley wheel is installed.

3. Apply:• Assembly grease

(on the torsion cam grooves and o-rings)4. Check:

• Sliding pulley wheel. Faulty operation Repair.

5. Install:• Clutch positioning bolt

Use the clutch spring compressor

6. Tighten:• Clutch positioning nut

Use the pulley wheel clamp Spanner (41 MM).

Clutch spring compressor90890-01337

Pulley wheel clamp90890-01701

5.0 m • kg


4-32

7. Install:• Conical pin• Crankcase cover seal• Secondary pulley wheel assembly • Clutch drum

8. Tighten:• Nut (secondary pulley wheel)

Use the pulley wheel support

9. Install• O-ring

PRIMARY PULLEY WHEEL1. Clean:

• Surface of primary sliding pulley wheel• Surface of primary fixed pulley wheel • Hubs • Rollers • Roller races

2. Install:• Counterbalance • Race • Runner • Hub

3. Check:• Operation of race Rough operation

Repair.

4. Install:• Primary pulley wheel assembly • Hub

5. Install:• Trapezoidal belt

NOTE:

The trapezoidal belt should be installed withthe arrow facing towards the front.

Pulley wheel clamp90890-01701

Clutch drum nut4.0 m • kg


4-33

6. Install:• Shim • Primary fixed pulley wheel • Washer • One-way clutch • Conical spring washer • Nut

7. Tighten:• Nut (primary pulley wheel)

NOTE:

When the nut is tightened (primary pulleywheel), support the magnetic flywheel usingthe engine wheel support tool

8. Adjust:• Trapezoidal belt

Tense the trapezoidal belt by turning theprimary pulley wheel several times

9. Install:• Fan

KICKSTART PEDAL1. Install:

• Return spring • Pedal axle • Bushing • Flat washer • Elastic circlip

Engine wheel support tool90890-01235

Primary pulley wheel nut3,3 m • kg

Screw (fan)0.7 m • kg


4-34

2. Hook on:• Return spring

(on pedal gear and hub)3. Install:

• Pedal pinion gear

4. Install:• Crankcase cover

5. Install:• Kickstart pedal

Screw (crankcase cover)7 Nm (0.7 m • kg)

Kickstart pedal0.9 m • kg


4-35

PISTON, CYLINDER AND CYLINDER HEAD

Carburettor gasket Reed valve Gasket Cylinder head Cylinder head gasket Cylinder

Cylinder seal Piston rings Piston10 Piston pin11 Circlips12 Bearing

SPARK PLUGMANUFACTURER/TYPE:

NKG/BR7HSGAP BETWEEN ELECTRODES

0.06 ~ 0.7 mm

CLEARANCE FROM PISTON TOCYLINDER:

0.034 ~ 0.047 mmLimit: 0.1 mm

BETWEEN ENDS (INSTALLED):Top ring

0.15 ~ 0.35 mmLimit:

0.60 mmSecond ring

0.15 ~ 0.35 mmLimit:

0.60 mm

LATERAL CLEARANCE:Top ring

0.03 ~ 0.05 mmLimit

0.10 mmSecond ring

0.03 ~ 0.05 mmLimit

0.10 mm


4-36

PISTON AND PISTON PIN1. Apply:

• Engine oil (in the crankshaft bearing, big end bea-ring, small end bearing, piston pin, pistonring grooves and piston skirt areas.)

2. Install:• Reed valve gasket• Reed valve • Carburettor gasket

3. Install:• Small end bearing• Piston • Piston pin • Piston circlips

NOTE:

• The arrow of the piston should point tothe exhaust side.

• Before installing the piston circlip, cover thecrankcase with a towel or clean cloth sothat the circlip and other materials do notaccidentally fall into the crankcase.

• Always use new piston circlips.

CYLINDER AND CYLINDER HEAD1. Install:

• Cylinder gasket (Use a new gasket)2. Check:

• Piston rings

NOTE:

• Ensure that the ends of the rings arecorrectly coupled around the centring devi-ces on the piston grooves.

• Check that the manufacturers symbols ornumbers printed on the rings are on theupper side of same.

Carburettor gasket0.9 m • kg


4-37

3. Install:• Cylinder

NOTE:

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

4. Install:• Cylinder head gasket (new gasket)

5. Install:• Cylinder head • Spark plug • Air protector

NOTE:

• The arrow “EX” from the cylinder headshould point to the exhaust side.

• Tighten the cylinder head positioning nutsin several steps, using a cris-cross pattern

6. Install:• Central stand • Spring • Axle • Clasp • Rubber washer • Strap loop

7. Install:• Brake shoes • Flat washer • Rear wheel

Cylinder head positioning screws1.4 m • kg

spark plug2.0 m • kg

rear wheel axle bolt12.5 m • kg


4-38

ASSEMBLY OF ENGINEWhen the engine is being assembled, reversethe removal procedure1. Install:

• Engine assembly bolt • Rear shock absorber bolt (lower)

2. Install:• Carburettor• Oil supply pipe• Fuel pipes• Air filter box assembly

NOTE:

• Align the projection of the carburettor withthe projections of the head

• Before installing the oil supply pipe, fill itwith oil.

3. Install:• Oil pipe • Oil supply pipe

NOTE:

Pass the oil supply pipe and the oil pipethrough as shown.

4. Bleed the air:• Autolubrication pump

Consult chapter 3, section – “BLEEDINGOF AIR FROM THE AUTOLUBRICATIONPUMP”.

5. Tighten:• Rear wheel axle nut

NOTE:

When the rear wheel axle nut is tightened,apply the rear brake.

Engine assembly bolt8.4 m • kg

Rear shock absorber bolt (lower)1.8 m • kg

1


4-39

6. Install:• Silencer • Fan cover

7. Apply:• Transmission oil.

See chapter 3 section - “CHANGINGTRANSMISSION OIL”.

8. Adjust:• Free play of brake levers.

See chapter 3, section – “ADJUSTMENTOF FREE PLAY OF FRONT/REARBRAKE LEVER”.

• Free play of accelerator cable See sec-tion “ADJUSTMENT OF FREE PLAY OFACCELERATOR CABLE”.

9. Install:• Helmet carrier• Overflow bowl• Footrest• Rear bodywork• Rear coverFollow the reverse process to the removal procedure.

10. Install:• Battery in its footrest housing

11. Connect:• Battery cables

12. Place:• Front cover

Bolt (silencer)2.6 m • kg

Bolt (exhaust pipe)0.9 m • kg

1

2

Positive cable + to positive terminal + of battery

Negative cable – to negative terminal – of battery

CARB 5

CHAPTER 5CARBURETOR

CARBURETOR ……………………………………………………………………5-1REMOVING THE CARBURETOR ……………………………………………5-2DISASSEMBLING THE CARBURETOR ……………………………………5-2CHECKING THE CARBURETOR ……………………………………………5-3ASSEMBLING THE CARBURETOR …………………………………………5-5CHECKING THE AUTOCHOKE UNIT ………………………………………5-6INSTALLING THE CARBURETOR……………………………………………5-7

FUEL COCK ………………………………………………………………………5-7CHECKING THE FUEL COCK ………………………………………………5-7

REED VALVE ………………………………………………………………………5-8REMOVING THE REED VALVE ………………………………………………5-8CHECKING THE REED VALVE ………………………………………………5-8INSTALLING THE REED VALVE………………………………………………5-9

CARB

CARBCARBURETOR

5-1

EAS00480

CARBURETORCARBURETOR

Throttle valve spring Spring catch Throttle valve Jet needle Pilot air screw Throttle stop screw Needle jet Main jet

Pilot jet10 Float11 Float gasket12 Drain screw13 Needle valve14 Float chamber15 Autochoke unit

13

11

14

10

12

carburetor dell’orto carburetor gurtner

15

13

11

14

10

15

CARBCARBURETOR

5-2

REMOVING THE CARBURETOR1. Remove:• air filter box• helmet box

Refer to “REAR BODYWORK, MUD-GUARD” in chapter 3

2. Drain:• fuel (from drain screw )

3. Disconnect:• autochoke lead coupler • fuel hose • vacuum hose • oil delivery hose • throttle cable (with throttle valve) • clamp (fixing clip)

4. Remove:• carburetor

DISASSEMBLING THE CARBURETOR1. Remove:• float chamber

2. Remove:• float pin • float • needle valve

3. Remove:• pilot jet • main jet • needle jet

CARBCARBURETOR

5-3

4. Remove:• throttle stop screw (with spring,

washer and o-ring)• pilot air screw (with spring)

5. Remove:• spring seat • jet needle • throttle valve • throttle valve spring

EAS00485

CHECKING THE CARBURETOR1. Check:• carburetor body

Dirty Clean

NOTE:

For cleaning, use a petrol based solvent. Cleanthe pipes and jets with compressed air

2. Check:• main jet • needle jet • pilot jet

Dirty Clean

3. Check:• needle valve

Wear/Dirty Clean• float

Damage Change• gasket Damage Change

CARBCARBURETOR

5-4

4. Check:• throttle valve

Wear/Damage Change

5. Check:• throttle valve displacement

Irregular movement/Catches ChangeInsert the throttle valve in the body and check its displacement.

6. Check:• throttle stop screw • pilot air screw • jet needle • starter plunger

Wear/Damage Change

7. Measure:• Float height a

Outside specifications Check valve,float and valve seat

Steps for measuring the height of the float:• Assemble the valve, float and axle on the

carburettor body• Turn the carburettor upside down• Using a vernier caliper, measure the distance

between the plane of the bowl gasket (wit-hout the gasket) and the upper part of thefloat.

Float height a 15.0 mm ~ 17.0 mm

CARBCARBURETOR

5-5

NOTE:

The arm of the float should be supported onthe valve without compressing it.• If the height of the float is not within the spe-

cified limits, inspect the valve and its seat.• Substitute both parts if any part of them is

worn.• If both are in good condition, replace the

float.• Check the height of the float again.

NOTE:

The height of the float is adjusted in the fac-tory. Do not try to modify it under any cir-cumstances.

EAS00487

ASSEMBLING THE CARBURETORThe assembly of the carburetor is carried outfollowing the reverse procedure to “DISAS-SEMBLY”. Bear in mind the following points:

CAUTION:• Before assembling the carburetor, wash

all of the parts in a petroleum-based sol-vent.

• Always use new gaskets.

1. Install:• jet needle • clip • throttle valve • spring seat• spring

2. Install:• throttle valve

NOTE:

Align the groove with the carburetor projec-tion .

Jet needle clip position:3/5 (Dell’orto) 2/3 (Gurtner)1/3 (Mofa Version)

CARBCARBURETOR

5-6

EAS00503

CHECKING THE AUTOCHOKE UNIT

NOTE:

When checking the autochoke unit, theambient temperature must be lower than 45°C(113°F).


2. Check:• autochoke unit

a. Connect a 3.3 mm hose to the starter airpassage and blow into the hose.

NOTE:

When the starter plunger is open, air shouldcome out of the other side of the starter airpassage.

3. Check:• autochoke unit

a. Connect the autochoke unit leads to a 12.0 V battery for five minutes.

b. Connect a 3.3 mm hose to the starter airpassage and blow into the hose.

Starter plunger Perform step (3)opens

Starter plunger Replace the auto-closes choke unit.

Positive batter lead yellow/red

Negtive battery lead black

Starter plunger Replace the auto-opens choke unit.

Starter plunger Autochoke is OK.closes

CARBCARBURETOR/ FUEL COCK

5-7

EAS00492

INSTALLING THE CARBURETOR1. Adjust:• engine idling speed

Refer to “ADJUSTING HE ENGINE IDLINGSPEED” in chapter 3.

2. Adjust:• throttle cable free play

Refer to “ADJUSTING HE ENGINE IDLINGSPEED” in chapter 3.

EAS00505

FUEL COCKCHECKING THE FUEL COCK1. Stop the engine.2. Remove:• helmet box

Refer to chapter 3, “REAR BODYWORK,MUDGUARD” section.

3. Inspect:• fuel cock

Steps for inspecting fuel cock:• Disconnect the fuel hose • Place a receptacle under the end of the fuel

hose.• Disconnect the vacum hose and suction

to create a vacuum• If the fuel comes out of the fuel hose as a

result of applying a vacuum and stops whenthe vacuum is stopped, the cock is in goodcondition. If not, clean or replace the vacuumhose, the fuel hose and cock.

Engine idling speed1.800 rpm

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

2 ~ 5 mm

CARBREED VALVE

5-8

REED VALVEREMOVING THE REED VALVE1. Remove:• helmet box

Refer to “REAR BODYWORK, MUD-GUARD” in chapter 3.

• air filter box assembly


See section “REMOVING THE CARBURE-TOR”

3. Remove:• carburetor joint • reed valve assembly

CHECKING THE REED VALVE1. Inspect:• carburetor joint

Damage/Cracks Change• reed valve

Fatigue/Cracks Change

Inspection steps:• Visually inspect the reed valve.• If there is any doubt on how to seal, apply

suction on the carburettor side.• Leaks should be light or moderate.

CARBREED VALVE

5-9

2. Measure:• valve stopper height

Out of specification Adjust the stop-per/Replace the valve stopper.

3. Measure:• clearance of reed valve

Out of specification Replace the reedvalve.

INSTALLING THE REED VALVEWhen the reed valve assembly is installed,reverse the removal procedure. Bear in mindthe following points.1. Install:• gasket

2. Tighten:• tighten the bolts for reed valve

NOTE:

Tighten each bolt gradually to avoid it beingdeformed.

Height of valve stopper 6.0 ~ 6.4 mm

Clearance of reed valve Less than 0.2 mm

Reed valve11 Nm (1.1 m • kg)

New

CHAS 6

CHAPTER 6CHASSIS

FRONT WHEEL …………………………………………………………………6-1EXTRACTION …………………………………………………………………6-2INSPECTION……………………………………………………………………6-2INSTALLATION …………………………………………………………………6-3

REAR BRAKE ……………………………………………………………………6-4CHANGE OF BRAKE BLOCKS ………………………………………………6-5DISASSEMBLY OF CALLIPER ………………………………………………6-6INSPECTION AND REPAIR …………………………………………………6-7ASSEMBLY OF CALLIPER ……………………………………………………6-7ASSEMBLY OF PUMP ………………………………………………………6-8

REAR WHEEL ……………………………………………………………………6-9EXTRACTION …………………………………………………………………6-10INSPECTION …………………………………………………………………6-10ASSEMBLY ……………………………………………………………………6-11INSTALLATION ………………………………………………………………6-12

REAR FORK ……………………………………………………………………6-13EXTRACTION …………………………………………………………………6-14DISASSEMBLY ………………………………………………………………6-14INSPECTION …………………………………………………………………6-15ASSEMBLY ……………………………………………………………………6-16INSTALLATION ………………………………………………………………6-18

HANDLEBAR AND STEERING ………………………………………………6-19REMOVAL ……………………………………………………………………6-20INSPECTION …………………………………………………………………6-21INSTALLATION ………………………………………………………………6-22

CHAS

CHASFRONT WHEEL

6-1

CHASSISFRONT WHEEL

Wheel axle Speedometer gear unit Bearing Spacer Hub Rim assembly

Tyre Oil seal Spacer10 Nut11 Washer

TYRE SIZE:120/70/12

RIM RUN-OUT LIMIT:Vertical: 1.0 mmLateral: 1.0 mm

WHEEL AXLE BEND LIMIT:0.25 mm

CHASFRONT WHEEL

6-2

REMOVAL1. Remove:

• brake caliper • Axle • Wheel

NOTE:

Do not press the brake lever when the wheelis removed from the scooter, otherwise thebrake blocks will be closed under force.

INSPECTION1. Measure:

• Bend of wheel axle Outside specified value Change

ss WARNING

Do not try to straighten a bent axle

2. Measure:• Run out of wheel


3. Inspect:• Wheel Cracks/Marked/Deformed

Change4. Inspect:

• Wheel bearings Bearings allow play on the wheel hub orthe wheel turns abruptly Change

5. Inspect:• Speedometer gear unit

Wear/Damage Change

Bend limitof wheel axle0.25 mm

Run-out limit:Vertical: 1.0 mmLateral: 1.0 mm

CHASFRONT WHEEL

6-3

INSTALLATIONReverse the removal process. Bear in mind thefollowing points.1. Lubricate:

• Front wheel axle• Bearings• Oil seal (edges)• Drive gear (speedometer)

2. Install:• Speedometer gear unit

NOTE:

Ensure that the two projections in the gearunit are engaging with the flat surface of thegear unit.

3. Install:• Front wheel

NOTE:

Ensure that the projection (torsion stopper) of the casing of the gear unit is correctlypositioned.

4. Tighten:• Front wheel axle:

ss WARNING:

Ensure that the brake pipe is correctlypositioned.

Recommended lubricant:Grease with lithium soap base

Front wheel axle:4.8 m • kg

CHASFRONT BRAKE

6-4

FRONT BRAKE

Retaining bolt Bleed screw Calliper assembly Block spring Pad set Piston seal Piston Brake disc

Master cylinder cap10 Diaphragm11 Hose12 Brake pump assembly13 Assembly plate14 Copper washer15 Assembly bolt16 Brake light switch cable

TYPE OF BRAKE FLUIDDOT 3 or 4

WEAR LIMIT OF BRAKE PADS:0.8 mm

WEAR LIMIT OF BRAKE DISC:3.0 mm

CHASFRONT BRAKE

6-5

EAS00583

REPLACING THE FRONT BRAKE PADS

NOTE:

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

1. Remove:• brake pad cover • brake pad clip • brake pad pin • brake pad spring

2. Remove:• brake pads

(along with the brake pad shims )3. Measure:• brake pad wear limit a

Out of specification Replace the brakepads as a set.

4. Install:• brake pad shims

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

NOTE:

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

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

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

c. Tighten the bleed screw.

d. Install a new brake pad shim onto eachnew brake pad .

a

a

Brake pad wear limit0.5 mm

Bleed screw6 Nm (0.6 m• kg)

CHASFRONT BRAKE

6-6

NOTE:

The triangle mark a on the brake pad shimmust point in the direction of disc rotation.

e. Install new brake pads and a new brakepad spring .

NOTE:

The arrow mark b of the brake pad springmust point in the direction of disc rotation.

5. Install:• brake pad pins• brake pad clips• brake pad cover

6. Chek:• brake fluid levelBelow the minimum level mark Add therecommended brake fluid to the proper level.Refer to “CHECKING THE BRAKE FLUIDLEVEL” in chapter 3.

7. Check:• brake lever operation

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

REMOVING THE BRAKE HOSE

NOTE:

Before replacing the brake hose, drain thebrake fluid from the entire brake system.

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

NOTE:

To collect any remaining brake fluid, place acontainer under the end of the brake hose.

b

CHASFRONT BRAKE

6-7

CHECKING THE BRAKE HOSE1. Check:• brake hoses

cracks/damage/wear Replace.

BRAKE HOSE ASSEMBLY

ss WARNING

• All internal parts should be cleaned onlyin new brake fluid.

• Internal parts should be lubricated withbrake fluid when installed.

1. Install:• Brake hose • Copper washers • Assembly bolts • Brake switch

ss WARNING

• The correct positioning of the hose isessential to ensure the safe operation ofthe scooter. See “CABLE ROUTING”.

• Always use new copper washers.

2. Ensure that the brake hose does not touchother parts (accelerator cable, installation,cables, etc.) by turning the handlebar to theleft and right. If it does touch, correct this.

12 3

4

Recommended brake fluidDOT 4

Assembly bolt:2.3 m • kg

CHASFRONT BRAKE

6-8

CHECKING THE BRAKE DISC1. Measure:

• Deflection of brake disc Outside specified value Inspect run-out of wheel.If the wheel is in good condition, changethe brake disc

• Brake disc thickness Outside specified value Change

Maximum deflection0.5 mm

Minimum thickness3.0 mm

Bolt (brake disc)2.0 m • kg

LOCTITE®

CHASREAR WHEEL

6-9

REAR WHEEL

Flat washer Valve Nut Flat washer Return spring

Brake shoe Brake cam Shoe axle Wear indicator10 Brake lever

Change:Brake shoes and returnspring as a set

TYRE SIZE:130/70-12

BRAKE DRUM WEAR LIMIT:110.5 mm

BRAKE SHOE WEAR LIMIT:2.0 mm

WHEEL RUN-OUT LIMIT:Vertical: 1.0 mmLateral: 1.0 mm

CHASREAR WHEEL

6-10

REMOVAL1. Remove:

• Exhaust pipe assembly2. Loosen:

• Rear axle nut

NOTE:

When the axle nut is loosened, apply rearbrake.

3. Remove:• Rear wheel

4. Remove:• Rear brake cable • Brake shoes • Flat washer

INSPECTION1. Inspect:

• Wheel See “INSPECTION OF REAR WHEEL”section

2. Measure:• Wheel run-out

See “INSPECTION OF REAR WHEEL”section

3. Check:• Wheel bearings Consult the “INSPEC-TION OF REAR WHEEL” section

4. Inspect:• Brake shoes Crystallisation Polishwith sand paper.

NOTE:

After using sand paper, clean the polishedparticles with a cloth.

Rim run-out limits:Vertical: 1.0 mmLateral: 1.0 mm

CHASREAR WHEEL

6-11

5. Measure:• Thickness of brake shoes a


6. Inspect:• Drum brake iner surface

Oil/Scratches Change

7. Measure• Drum brake inner diameter a:

Out of specification Change

ASSEMBLYWhen the brake shoe carrier plate is assem-bled, reverse the removal procedure.Bear in mind the following points.1. Install:

• Brake cam

NOTE:

Apply Grease with a lithium soap base on thebrake camand pin .

ATTENTION:

After installing the brake cam, removeexcess grease.

2. Install:• Brake shoes • Return spring

NOTE:

Install with the mark outwards.

3. Install:• Torsion spring • Wear indicator • Cam lever

NOTE:

• Align the projection of the wear indicator with the line as shown.

• Align the punch marks .

Brake shoes thickness4.0 mm

Limit: 2.0 mm

Wear limit of brake drum110.5 mm

31

2

1

23

4

2

1

CHASREAR WHEEL

6-12

4. Install:• Flat washer • Brake cable

INSTALLATIONWhen installing the rear wheel, reverse theremoval procedure.The following points should be remembered.1. Install:

• Rear wheel• Flat washer • Nut

2. Install:• Silencer

3. Adjust:• Free play of rear brake lever

See section in chapter 3 “CHECKINGFREE PLAY OF REAR BRAKE LEVER”.

Bolt (cam lever):0.7 m • kg

Nut (Rear wheel axle):12.5 m • kg

Bolt (exhaust pipe side):0.9 m • kg

Bolt (silencer side):2.6 m • kg

CHASFRONT FORK

6-13

FRONT FORK

Front fork assembly (left) Rubber cap Restraining ring Restraining ring Cap O-ring Dust guard Retainer

Oil seal10 Fork spring11 Sliding metal12 Shock absorber rod13 Return spring14 Bar15 Oil lock piece16 Outer tube17 Front fork assembly (right)

FREE LENGTH OF FORK SPRING:LIMIT:

LEFT 226 mmRIGHT 226 mm

FORK OIL CAPACITY:50 cc ± 1 cc

GRADE: 10 W oil fork or equivalent

CHASFRONT FORK

6-14

REMOVAL1. Place the scooter on its central stand and

place an adequate support under the engi-ne

2. Remove:• Brake callipers

Consult “FRONT BRAKE REMOVAL” sec-tion

3. Remove:• Front wheel

See “FRONT WHEEL REMOVAL SEC-TION”

4. Remove:• Mudguard, front fairing

See chapter 3 “FRONT BODYWORK,MUDGUARD”

5. Loosen:• Positioning bolt (fork)

6. Remove:• Restraining ring • FRONT FORK

DISASSEMBLY1. Remove:

• Rubber cap• Restraining ring • Cap• Fork spring

2. Drain:• Fork oil

3. Remove:• Mudguard• Retainer

1

3

2

CHASFRONT FORK

6-15

4. Remove:• Bolt (shock absorber rod) • Copper washer

NOTE:

Remove the bolt (shock absorber rod) whilethe shock absorber rod is held with the T-handle and a support

5. Remove:• Inner pipe• Shock absorber rod• Oil lock piece (left side)• Oil seal

INSPECTION1. Inspect:

• Fork bar• Outer tube• Shock absorber rod

Striping/Warping/Wear/Damage

Change

ss WARNING

Do not try to straighten a fork bar or anouter tube as this may dangerously wea-ken the tube.

2. Measure:• Fork spring

Above specified limit Change

3. Inspect:• Oil lock piece• O-ring (cover)

Wear/Damage Change

T-handle:90890-01326

Support:90890-01294-A

Free length of fork spring (limit) :Left 226 mmRight 226 mm

CHASFRONT FORK

6-16

ASSEMBLYReverse the disassembly procedure. Bear inmind the following points.

NOTE:

• When assembling the fork, ensure that thefollowing new parts are used.

• Oil seal• Mudguard• Sliding metal• Ensure that all components are clean before

assembly.

1. Install:• Shock absorber rod• Oil lock piece (left side)• Bar • Copper washer (new)• Bolt (shock absorber rod)

NOTE:

Tighten the bolt (hydraulic rod) while suppor-ting the bar with the T-handle and the sup-port .

2. Install:• Oil seal

Use a counterbalance for installing forkseals and an adaptor .

NOTE:

Before installing the oil seal, apply greasewith a lithium soap base on the edges ofsame.

ATTENTION:

Ensure that the numbered side of the sealis facing upwards.

Bolt (hydraulic rod):23 Nm (2.3 m • kg, 17 • lb)LOCTITE®

T-handle:90890-01326

Support:90890-01294-A

Counterbalance for installing oilseals:

90890-01184Adaptor:

90890-01186

CHASFRONT FORK

6-17

3. Install:• Retainer • Dust guard

NOTE:

Couple the retainer correctly on the groove ofthe outer tube .

4. Fill :• Fork oil

NOTE:

Place the fork in a vertical position.

5. Install:• Fork spring• Cover• Restraining ring• Rubber cap

NOTE:

• Before installing the cover, apply grease tothe o-ring.

• Couple the restraining ring correctly on theinner tube groove.

Each fork:50 cm3

10 W fork oil or equivalent after filling, slowly pump the fork to distribute the oil.

Oil level:95 mm

From the upper part of the innerfork tube totally compressed wit-hout the spring.

CHASFRONT FORK

6-18

INSTALLATIONReverse the removal procedure.The following points should be remembered1. Install:

• Front fork:• Stopper ring

NOTE:

Attach the stopper ring correctly on the innertube groove.

2. Tighten:• Positioning bolt (lower bracket)

3. Install:• Front wheel• Brake calliper• Clasp (brake hose)• Speedometer cable

See “FRONT WHEEL” section• Front mudguard

See chapter 3, section “FRONT BODY-WORK MUDGUARD”

Positioning bolt (inner lever arm)30 Nm (3.0 m • kg, 22 ft • lb)

Wheel axle48 Nm (4.8 m • kg, 35 ft • lb)

CHASHANDLEBAR AND STEERING

6-19

HANDLEBAR AND STEERING

Handlebar Grip cap Throttle grip Throttle grip guide Grip Nut Bolt Throttle cable Brake cable10 Upper ring nut

11 Lock washer12 Center ring nut13 Rubber washer14 Lower ring nut15 Bearing cover16 Upper bearing race17 Bearing cage18 Bearing race19 Lower bracket

10

11

13

15

17

16

18

19

12

14

16

18

17


6-20

REMOVAL1. Place the scooter on its central stand and

place a suitable support under the engine.2. Remove:

• Front wheel See section “REMOVAL OF FRONTWHEEL”

3. Remove:• Mudguard• Front fairing

See chapter 3,“FRONT BODYWORK,MUDGUARDS” section.

4. Remove:• Handlebar covers See chapter 3 “HAND-LEBAR COVER” section

NOTE:

Before completely removing the rear coverwith the speedometer, disconnect the spee-dometer cable and the signalling and lightingsystem cables.

5. Remove:• Front fork

See “REMOVAL OF FRONT FORK” sec-tion

6. Remove:• Brake pump support• Brake pump.• Throttle grip

7. Remove:• Flange (electrical installation)

12

1


6-21

8. Remove:• Upper ring nut

ss WARNING

Support the steering axle so that it doesnot fall.

9. Remove:• Lock washer• Central ring nut• Rubber washer• Lower ring nut• Bearing cover• Lower bracket

INSPECTION1. Wash the bearing and race with solvent.2. Inspect:

• Bearings• Bearing race

Pitted/Damage Change

Steps for replacing the bearing race:• Remove steering bearing races using a long

rod and the hammer as shown.• Remove the bearing race from the shaft

using a chisel and the hammer asshown.

• Install the new mudguard and the guides.

Ring nut wrench for steering90890-01403


6-22

NOTE:

• Always change the bearing and the racestogether.

• Change the mudguard whenever the stee-ring head is disassembled.

ATTENTION:

If the bearing race is not coupled correctly,the steering tube may be damaged.

3. Inspect:• Lower lever arm (with steering rod)

Cracks/Damage Change

4. Inspect:• Handlebar

Cracks/Damage Change

ss WARNING

Do not try to straighten a bent handlebarsince this can weaken it dangerously.

INSTALLATIONReverse the steps for disassembly and remo-val. The following points should be remembe-red1. Apply:

• Wheel bearing grease (on upper bearings and lower bearings.)

2. Install:• Lower bracket • Lower ring nut • Rubber washer • Central ring nut • Lock washer • Upper ring nut

ATTENTION:

Support the steering column until it is inposition.


6-23

3. Tighten:• Steering nut

Steps for tightening the steering nut:1. Tighten the lower ring nut to 3.8 m•kg.2. Loosen the lower ring nut 1/2 of a turn

and tighten to 0.65 m•kg.3. Check the steering for smooth operation.4. Install rubber washer .5. Install central ring nut and hand tighten

untill the lower and central ring nuts slotsallignet.

6. Install the lock washer .7. Supporting the lower and central ring nuts,

install and thigten the upper ring nut to 7.5m•kg.

4. Install:• Handlebar • Bolt • Nut

NOTE:

Match up the bolt on the tooth of the stee-ring column .

5. Install:• Flange

NOTE:

Support electrical installation


(on the end of the accelerator cable andright end of the handlebar.)

Bolt (handlebar)4.3 m • kg


6-24

7. Install:• Brake pump

NOTE:

First tighten the upper bolt, then the lowerbolt.

8. Install:• Rear handlebar cover with speedometer• Front handlebar cover

NOTE:

Connect the speedometer cables, signallingand lighting systems.

ATTENTION:

Situate the speedometer cable through itshousing in the rear cover.

9. Install:• Front fork

See “INSTALLATION OF FRONT FORKSECTION”.

10. Install:• Front wheel

See section “INSTALLATION OF FRONTWHEEL”

1

Bolt (brake pump)0.9 m • kg

ELEC 7

CHAPTER 7ELECTRICAL SYSTEM

ELECTRICAL COMPONENTS …………………………………………………7-1

IGNITION AND STARTER SYSTEM……………………………………………7-3CIRCUIT DIAGRAM ……………………………………………………………7-3IGNITION AND STARTER CIRCUIT SYSTEM………………………………7-4TROUBLESHOOTING …………………………………………………………7-5

CHARGING SYSTEM …………………………………………………………7-10CIRCUIT DIAGRAM …………………………………………………………7-10LOCATION AND REPAIR OF FAULTS ……………………………………7-11

LIGHTING SYSTEM ……………………………………………………………7-13CIRCUIT DIAGRAM …………………………………………………………7-13LOCATION AND REPAIR OF FAULTS ……………………………………7-14CHECKING OF LIGHTING SYSTEM ………………………………………7-15

SIGNALLING SYSTEM …………………………………………………………7-17CIRCUIT DIAGRAM …………………………………………………………7-17LOCATION AND REPAIR OF BREAKDOWNS ……………………………7-18CHECKING OF SIGNALLING SYSTEM……………………………………7-19

ELEC

ELECELECTRICAL COMPONENTS

7-1

Wire harness Starter motor CDI unit Engine oil level gauge Starter relay Fuel level gauge Battery Ignition coil

ELECTRICAL SYSTEMELECTRICAL COMPONENTS

IGNITION COIL:PRIMARY COIL RESISTANCE:

0.56 ~ 0.84 Ω at 20 °C (68 °F)SECONDARY COIL RESISTANCE:

5.7 ~ 8.5 Ω at 20 °C (68 °F)

BATTERYSPECIFIC GRAVITY: 1,280

ELECELECTRICAL COMPONENTS

7-2

Main switch/seat lock Turn signal relay Rectifier/regulator Horn

ELECIGNITION AND STARTER SYSTEM

7-3

. CDI magneto. CDI . Spark plug. Main switch. Fuse. Battery. Starter relay

10 . Starter motor11 . “START” switch24 . Front brake switch25 . Rear brake switch34 . Ignition coil

IGNITION AND STARTER SYSTEMCIRCUIT DIAGRAM


7-4

SISTEMA DE ENCENDIDO Y ARRANQUE

Spark plug Ignition coil CDI unit Starter motor Starter relay Fuse10 Battery

11 Starter switch12 Main switch18 Front brake switch19 Rear brake switchB Pick-up coilG To oil level switch

RB

LOCK

OPEN

OFF

CHECK

ON

Br

GB/W

DC

CDI

UNIT

B/W

Br

B

0

B

W/LB

B

Current which flows in the ignition control circuit

Current which flows in the starter motor control circuit

INDUCED COIL RESISTANCE:0.05 ~ 0.06 _ at 20 °C (68 °F)

BRUSH WEAR LIMIT:0.9 mm

COMMUTATOR WEAR LIMIT:16.6 mm

MICA LOWER CUT-OFF:1.35 mm


7-5

TROUBLESHOOTING

NOTE:

• Remove the following parts before carrying out the repair of fault .1) Side covers (right and left)2) Rear cover 3) Footrest panel

• Use the following special tools to repair faults.

IF THE IGNITION SYSTEM IS NOT OPERATING(NO SPARK OR INTERMITTENT SPARK)

Ignition tester:90890-06754

Pocket tester:90890-03112

1. Spark plug

• Check spark plug conditions.• Check type of spark plug.• Check distance between electrodes .

Consult chapter 3 “INSPECTION OFSPARK PLUG”

CORRECT

2. Gap of the ignition spark plug

• Disconnect the spark plug pipe from thespark plug.

• Connect the ignition tester as shown. Spark plug pipe Spark gap• Check spark gap• Start the engine and increase the spark

jump until ignition fails.

Minimum spark gap:6.0 mm

OUTSIDE SPECIFIEDVALUE ORNO SPARK

INCORRECT

Defective spark plug, change or adjust thedistance between the electrodes

Standard spark plugBR7HS (NGK)

Distance between electrodes0.6 ~ 0.7 mm

SATISFIES THE SPECIFIED VALUE

The ignition system is in good condition.


7-6

3. Spark plug cap resistance

• Remove spark plug cap• Connect the pocket tester (Ωx1k) on the

spark plug cap.• Check if the spark plug pipe has the spe-

cified resistance

Resistance of spark plug:5 kΩ at 20 °C (68 °F)

SATISFIESTHE SPECIFIEDVALUE

4. Resistance of ignition coil

• Disconnect the ignition coil cables.• Connect the pocket tester (Ωx1) on the

ignition coil .

Ignition coil:Cable (+) of tester Terminal +(orange)Cable (–) of tester Terminal –(ground)

• Check if the primary coil has the specifiedresistance.

Primary coil resistance:0.56 ~ 0.84 Ω at 20 °C (68 °F)

• Connect the pocket tester (Ωx1k) on theignition bobbin.

Cable (+) of tester Cable of sparkplugCable (–) of tester Ground

• Check if the secondary coil has the speci-fied resistance.

Secondary coil resistance:5.7 ~ 8.5 kΩ at 20 °C (68 °F)(Spark plug cable - Coil cable)

BOTH SATISFY THE SPECIFIEDVALUE

OUTSIDE SPECIFIED VALUE

Replace the spark plug cap


The ignition coil is defective, replace it


7-7

5. Pick up coil resistance

• Disconnect the Pick up coil coupler of theinstallation

• Connect the pocket tester (Ωx100) on thepick up coil terminal.

Cable (+) of tester White blueCable (–) of tester Black

• Check if the pick up coil has the specifiedresistance.

Resistance of harnessing coil250 ~ 370 Ω at 20 °C (68 °F)


CORRECT

6. Connections

Check the connections throughout the igni-tion system for connections.Consult the “ELECTRICAL DIAGRAM”sec-tion

Replace the CDI unit.


The pick up coil is defective, replace it

Correct


7-8

NOTE:

• Remove the following parts before repairing the faults.1) Side covers (right and left)2) Rear cover 3) Front mudguard 4) Handlebar cover (upper)

• Use the following special tool for these repairs.

THE STARTER MOTOR DOES NOT FUNCTION


1. Fuse

• Remove the fuse.• Connect the pocket tester (Ωx1) on the

fuse.• Check the fuse to see if there is continuity.

2. Battery

• Check the conditions of the battery.Consult the “INSPECTION OF THE BAT-TERY” section in chapter 3.

CONTINUITY

CORRECT

Open circuit voltage:12.8 V or more at 20 °C (68 °F)

• Check the operation of the starter motor.

3. Starter motor

• Connect the positive terminal of the battery and the starter motor cable using abridge cable *

STARTER MOTORTURNS

NO CONTINUITY

The fuse is defective

INCORRECT

• Clean the battery terminals• Recharge or change battery.

STARTER MOTOR DOESN’T TURN

The starter motor is defective, repair orchange.

ss WARNING:

• The bridge cable should have the samecapacity as the cable or more, otherwisethe cable may burn .

• This composition may cause sparks, as aresult, ensure that there are no gases orinflammable liquids in the area.


7-9

4. Starter relay

• Disconnect the starter relay cable from theinstallation.

• Connect the battery to the starter relaycables as shown using the bridge cables.

• Check the operation of the starter motor.

DOES MOVE

5. Main switch

• Disconnect the coupler of the main switchfrom the installation.

• Check the switch component to see ifthere is continuity between “Red andBrown ”.

6. Starter switch

• Disconnect the coupler of the handlebarswitch (right) from the installation.

• Check the starter switch component to seeif there is continuity between “Blue/Whiteand Black ”

CORRECT

CORRECT

7. Connections

• Check the connections throughout the igni-tion system.See the “ELECTRICAL DIAGRAM”

INCORRECT

The main switch is defective, change.

DOESN’T MOVE

The starter relay is defective, change

INCORRECT

The starter switch is defective, change thehandlebar switch (right).

BAD CONNECTION

Correct

ELECCHARGING SYSTEM

7-10

CHARGING SYSTEMCIRCUIT DIAGRAM

Flywheel Magneto Fuse Battery Rectifier/Regulator

ELECCHARGING SYSTEM

7-11

TROUBLESHOOTING

NOTE:• Remove the following parts before carrying out the repair of the fault.

1) Side covers (right and left)2) Rear cover

• Use the following special tool for this repair.

THE BATTERY IS NOT CHARGED

Inductive tachometer:90890-03113


1. Fuse (main)

• Remove the fuse.• Connect the pocket tester (Ωx1) to the

fuse.• Check the fuse to see if there is continuity

2. Battery

• Check the condition of the battery.See chapter 3, section “INSPECTION OFTHE BATTERY”.

CONTINUITY

OUTSIDE SPECI-FIED VALUE


3. Charging voltage

• Connect the inductive tachometer on thespark plug cable

• Connect the pocket tester (20 V CC) on thebattery.

Cable (+) of the tester Terminal (+) Cable (–) of the tester Terminal (–)

• Start the engine and accelerate to 5,000rpm/min.

• Check charging voltage.

Charging voltage:14 ~ 15 V at 5,000 rpm/min.

CORRECT

NOTE:

Use a fully charged battery.

NO CONTINUITY

The fuse is defective, change.

INCORRECT

• Clean the battery terminals• Recharge or change the battery.


The charging circuit is in good condition.

ELECCHARGING SYSTEM

7-12

4. Charge coil resistance

• Disconnect the charge coil coupler from theinstallation.

• Connect the pocket tester(Ωx1) on thecharge coils.

• Measure the resistances of the charge coil.


5. Connections

Check the connections throughout the igni-tion system.Consult the “ELECTRICAL DIAGRAM” sec-tion.

Cable (+) of the tester White cable Cable (–) of tester Yellow/Red Cable

Charge coil resistance:0,288 ~ 0.432 Ω at 20 °C (68 °F)

GOOD

Change the rectifier/regulator


The charge coil is defective, change

BAD CONNECTION

Correct.

ELECLIGHTING SYSTEM

7-13

LIGHTING SYSTEMCIRCUIT DIAGRAM

Flywheel 14 Light dinmer switch16 Headlamp21 Brake and rear light27 Meter light

ELECLIGHTING SYSTEM

7-14

TROUBLESHOOTING

NOTE:

• Remove the following parts before repairing the faults. 1) Side covers (right and left)2) Rear cover 3) Handlebar cover (upper)

• Use the following special tool for these repairs.

HEADLAMP, “HIGH BEAM” LIGHT INDICATOR, REAR LIGHT AND/OR METER LIGHT DO NOT LIGHT UP


1. Light switch “k j”

• Disconnect the coupler of the main switch(left) from the installation.

• Place the switch “k j” in position “j”.• Check the switch component to see if

there is continuity between “Blue/Yellow”and “Blue/Green ”.

2. Resistance of the lighting coil

• Disconnect the lighting coil coupler fromthe installation

• Connect the pocket tester (Ωx1) on thelighting coils.

• Measure the resistances of the lighting coil.

correct

Cable (+) of tester Yellow/Red Cable (–) of tester Ground

Lighting coil resistance:0,176 ~ 0,264 Ω at 20 °C (68 °F)

SATISFIES THESPECIFIED VALUE

INCORRECT

The “LIGHTS” switch (intensity control) isdefective, Change the handlebar switch(left).


The lighting coil is defective, change.

ELECLIGHTING SYSTEM

7-15

3. Connections

Check the connections throughout the ligh-ting system.See “ELECTRICAL DIAGRAM” section

CORRECT

The circuit is in good condition

CHECKING LIGHTING SYSTEM1. The headlight does not light

1. Bulb and bulb holder

• Check the bulb and bulb holder to see ifthere is continuity.

CONTINUITY

2. Voltage

• Connect the pocket tester (20 V AC) on theheadlight.

Headlamp light:Cable (+) of Yellow or GreenCable (–) of tester Black

A When the switch “k j”(intensity control)is in position “k”.

B When the switch “k j” (intensity control)is in position “j”.

• Place the main switch on “f”.• Start the engine.• Place the switch “k j” (dimmer switch) in

position “k” or “j”.• Check if there is a voltage (12 V) in the

“Green” and “Yellow” cable in the connec-tors of the bulb holder.

SATISFIES THE SPECIFIEDVALUE (12 V)

The circuit is in good condition.

BAD CONNECTION

Correct

NO CONTINUITY

Replace the bulb and/or bulb holder.


The connection circuit of the main switch tothe bulb holder connector is defective, repairit.

ELECLIGHTING SYSTEM

7-16

NO CONTINUITY




NO CONTINUITY




2. The panel light does not light.


• Check the bulb and bulb holder to see ifthere is continuity.

CONTINUITY

2. Voltage

• Connect the pocket tester (20 V AC) on thebulb holder coupler.

Cable (+) of the tester Blue terminal Cable (–) of tester Black terminal

• Place the main switch on “ON”• Check if there is a voltage (12 V) in the

“Blue cable” of the connector of the bulbholder.

The circuit is in good condition


SATISFIES THESPECIFIEDVALUE(12 V)

1. Bulb and bulb holder.

• Check the bulb and bulb holder for conti-nuity.

3. The rear light does not light.

CONTINUITY

2. Voltage

• Connect the pocket tester (20 V AC) in thebulb holder connector .

Cable (+) of the tester Blue terminal Cable (–) of tester Black terminal

• Place the main switch on “ON”.• Start engine.• Check if there is a voltage (12 V on the

“Blue” cable of the bulb holder connec-tor).

SATISFIES THESPECIFIED VALUE(12 V)

ELECSIGNALLING SYSTEM

7-17

SIGNALLING SYSTEMCIRCUIT DIAGRAM

Speed sensor Main switch Fuse Battery13 Horn13 “HORN” switch15 “TURN” switch17 Front indicator light (Left)18 Front indicator light (Right)19 Rear indicator light (Left)

20 Rear indicator light (Right)21 Tail light22 Horn23 Indicator relay24 Front brake switch25 Rear brake switch26 Oil level switch27 Motor lights28 Fuel sensor


7-18

TROUBLESHOOTING

NOTE:

• Remove the following parts before repairing the faults .1) Front cover . 4) Front lower fender2) Inner cover3) Rear panel (battery box)

• Use the following special tool for the repairs.

• INDICATOR LIGHT, BRAKE LIGHT, AND/OR INDICATING LIGHTS DO NOT LIGHT.• THE HORN DOES NOT SOUND


1. (Main) fuse

• Remove the fuses.• Connect the pocket tester (Ωx1) on the

fuses.• See “INSPECTION OF FUSES” in chapter

3.

2. Battery

• Check the operation of the battery. See section “INSPECTION OF THE BAT-TERY” in chapter 3.

CORRECT



CORRECT

3. Main switch

• Disconnect the main switch coupler of theinstallation

• Check the switch component for continuitybetween “Red and Brown ” and “Red and Gray ”.

NO CONTINUITY

The fuse is defective, change.

INCORRECT

• Clean the battery terminals• Charge or change the battery.

INCORRECT

The main switch is defective, change


7-19

4. Connections

• Check the connections throughout the sig-nalling system.

• See the “ELECTRICAL DIAGRAM”section

Check the conditions for each signalling sys-tem circuit. Consult the “CHECKING SIGNALLING SYS-TEM” section.

CHECKING SIGNALLING SYSTEM

1. Horn does not operate

1.“HORN” switch.

• Disconnect the coupler of the handlebarswitch (left) from the installation and horncable.

• Check the switch component for continuitybetween “Black and Red ”.

2. Voltage

• Connect the pocket tester (20 V DC) on thehorn cable.

Cable (+) of the tester Brown Cable (–) of tester Frame earth

• Place the main switch on “ON”• Check if there is a voltage (12 V) in the

brown cable of the horn terminal.

SATISFIES THE SPECIFIEDVALUE (12 V)

CORRECT

CORRECT

BAD CONNECTION

Repair

INCORRECT

The “HORN” switch is defective, change thehandlebar switch (left).


The connection circuit from the main switchto the horn terminal is defective, repair.


7-20

3. Horn

• Disconnect the “Pink” cable from the hornterminal.

• Connect a bridge cable on the horn ter-minal and earth the bridge cable.

• Place the main switch on “ON”.

2.The brake lights do not light.

1.Bulb and bulb holder.

• Check the bulb and bulb holder for conti-nuity

SATISFIES THE SPECIFIEDVALUE

4. Voltage

• Connect the pocket tester (20 V DC) on thehorn, on the “Pink” terminal.

THE HORN DOES NOT SOUND.

Cable (+) of tester Pink Cable (–) of tester Earth of frame

• Place main switch on “ON”.• Check if there is a voltage (12 V) in the

“Pink” cable on the horn terminal.

Adjust the horn.

CONTINUITY

2.Brake switch

• Disconnect the brake switch cables fromthe installation.

• Check the switch component for continuitybetween “Brown and Green/Yellow ”.


The horn is defective.

NO CONTINUITY

Change the bulb and/or bulb holder.

THE HORN SOUNDS

The horn is in good condition.


7-21

3. The Master lights do not flash.

1. Bulb and bulb holder.


CORRECTO

3.Voltage

• Connect the pocket tester (20 V DC) on thebulb holder connector.


CONTINUITY

2.Turning signal switch “b”

• Disconnect the handlebar switch coupler(left) from the installation.

• Check the switch component for continuitybetween “Brown/white” and “Chocolate” and “Brown/White” and “Darkgreen”

Cable (+) of tester Green/Yellow Cable (–) of tester Black

• Place the main switch on “ON”.• Activate the brake lever.• Check if there is a voltage (12 V) on the

“Green/Yellow” cable of the bulb holderconnector.


CORRECT

INCORRECT

The brake switch is defective, change.


The connection circuit from the main switchto the connector of the bulb holder isdefective, change.

NO CONTINUITY

Change the bulb and/or bulb holder.


7-22

3.Voltage

• Connect the pocket tester (20 V DC) on theflasher relay .

SATISFIES THE SPECIFIED VALUE(12 V)

Cable (+) of tester BrownCable (–) of tester Fame ground

• Place the main switch on “ON”.• Check if there is a voltage (12 V) on the

“Brown” cable and “Frame ground” of theflasher relay terminal.

• Place the main switch on “ON”• Chek it there is a vollàge (12V) on the

“Brown / White” cable and “Frame ground”of the flasher relay terminal.

Cable (+) of tester White/BrownCable (-) of tester Frame ground

SATISFIES THESPECIFIED VALUE(12V)

4. Voltage

• Connect the pocket tester (20VDC) on theflaster relay.

5. Voltage

• Connect the pocket tester (20 V DC) on thebulb holder receptacle.

On the indicator light (left):Cable (+) of the tester Chocolate Cable (–) of tester Frame ground

On the indicator light (right):Cable (+) of tester Dark Green Cable (–) of tester Frame ground

INCORRECT

The “TURN” is defective, change the hand-lebar switch (left).


The flasher relay is faulty, change


The indicator relay is defective, change


7-23

Switchposition

Goodcondition

Bad condition

• Place the main switch on “f”.• Place the switch “b” on position “c” or

“d”.• Check if there is a voltage (12 V) on the

“Chocolate” or “Dark Green” cable of thebulb holder connector.



4. The oil indicator light “OIL” does not light.



CONTINUITY

2.Oil level switch

• Remove the oil sump oil level switch.• Connect the pocket tester (Ωx1) on the oil

level switch.

Cable (+) of tester Terminal Cable (–) of tester Terminal

• Check the oil level measurer for continuity.

A Vertical position x x upwards

B Reverse position x x

: Continuity x: No continuity

GOOD CONDITION

3. Voltage

• Connect the pocket tester (20 V DC) onthe bulb holder connector .

Cable (+) of tester Gray Cable (–) of tester Frame ground


The connection circuit from the “TURN”switch to the bulb holder connector isdefective, review.

NO CONTINUITY

Change the bulb and/or bulb receptacle.

POOR CONDITION

Change the oil level switch.


7-24

• Place main switch on “*”• Check if there is a voltage (12 V) on the

“Gray” cable of the bulb holder connector

SATISFIES THE SPECIFIED VALUE(12 V)


5. The speedometer fails to come on.

1. Voltage

• Connect the pocket tester (DC 20 V) to themulti-function meter socket coupler (wireharness side) as shown.

Positive tester probe red/yellow Negative tester probe black/yellow

LY

Br

Ch Dg

R B

Gy GR

BY Sb G LG

Dg Ch L GR Y Gy

RBrBBYSbG

RY

RYLG

RY/

LG/

BY/

13 2

• Set the main switch to “ON”.• Measure the voltage (DC 12 V) of

red/yellow on the multi-function metercoupler (wire harness side).

• Is the voltage within specification?

Replace the speedsensor.

YES NO


4. Connections

• Check the connections throughout the sig-nalling system. See the “ELECTRICAL DIAGRAM” section.

This circuit is OK.


7-25

2. Speed sensor

• Connect the pocket tester (DC 20 V) to thespeed sensor coupler (wire harness side)as shown.

Positive tester probe blue/green Negative tester probe black/yellow

L B R BY/

RY/

LG/

• Set the main switch to “ON”.• Elevate the front wheel and slowly rotate it.• Measure the voltage (DC 12 V) of

red/yellow and black/yellow. With each fullrotation of the front wheel, the voltage rea-ding should cycle from 0 V to 5 ~ 11V to 0V to 5 ~ 11V, etc.

• Does the voltage reading cycle correctly?

Replace the speedsensor.

YES NO

The circuit is OK.

LOCAVER 8

?

CHAPTER 8LOCATION AND REPAIR OF BREAKDOWNS

LOCATION AND REPAIR OF ENGINE BREAKDOWNS ……………………8-1ELECTRICAL SYSTEM ………………………………………………………8-1COMPRESSION SYSTEM ……………………………………………………8-2INLET AND EXHAUST SYSTEM ……………………………………………8-3

ELECTRICAL DIAGRAM YN50

LOCAVER

LOCAVERTROUBLE SHOOTING

8-1

ELECTRICAL SYSTEM

* CHECK ALL CABLE CONNECTIONS

MAIN SWITCH• The main switch is short

circuited.

SPARK PLUG• Excessive carbon deposits.• Damp electrodes.• Incorrect gap.• Broken.

SOURCE COIL• The coils are broken.

PICK-UP COIL• The coils are broken.• Incorrect ignition distribution.

CDI UNIT• CDI unit defective

IGNITION COIL• The primary and secondary

coils are broken or defective.• The high voltage cable is

defective.• The spark plug cap is

defective.


8-2

COMPRESSION SYSTEM

FATIGUE/CRACKS

DEFECTIVE SEALING

DAMAGEDAMAGE/WEAR

WEAR/CRACKS/DAMAGE

INSUFFICIENT TIGHTENING TORQUE

WEAR/STRIPING

WEAR/CATCHING/BREAKS

CARBON DEPOSITS

WARPING/CARBON DEPOSITS

DAMAGE/WEAR

DAMAGE

DAMAGE


8-3

INLET AND EXHAUST SYSTEM

CARBURETTOR JOINT• Air leaks

MAIN JET• Incorrect size• Obstructed (High speed)

MUFFLER• Obstructed

EXHAUST PIPE• Cracked or broken• Carbon deposits

NEEDLE• Badly adjusted

(Average speed)

PILOT JET• Obstructed (Low range)

FLOAT• Incorrect adjustment of fuel level• Broken

FUEL TANK CAP• Obstructed

FUEL PIPE• Obstructed

AIR FILTER ELEMENT• Dirty or obstructed

FUEL COCK• Obstructed

AIR SCREW• Badly adjusted

(Idling and starting)

ACCELERATOR STOPPING SCREW• Badly adjusted

(Idling and starting)

BOWL• Accumulated dust and/or water

FLOAT VALVE• Worn

DAMP TYPE

(CARBURETTOR)

COMPONENTS

1. Flywheel magneto2. CDI UNIT3. SPEED SENSOR4. Spark plug5. Main switch6. Fuse7. Battery8. Rectifier/regulator9. Starter relay

10. Starter motor11. Starter switch13. Horn switch14. Dimmer switch15. Turn lights switch16. Headlight17. Front left turn light18. Front right turn light19. Rear left turn light20. Rear right turn light21. Tail light22. Horn23. Turn lights relay24. Front stop switch25. Rear stop switch26. Oil level switch27. Instrument panel28. Fuel sender31. License light (UK only)33. Auto choke34. Ignition coil

COLOUR CODE

B ...............................BLACKR ...............................REDL................................BLUEG...............................GREENO...............................ORANGEY ...............................YELLOWP ...............................PINKBR.............................BROWNCH ............................CHOCOLATESB.............................SKY BLUEDG ............................DARK GREENW ..............................WHITEB/BR.........................BLACK/BROWN.B/Y............................BLACK/YELLOWB/R ...........................BLACK/REDB/W...........................BLACK/WHITEG/R ...........................GREEN/REDG/Y ...........................GREEN/YELLOWBR/W ........................BROWN/WHITEW/R...........................WHITE/REDW/B...........................WHITE/BLACKW/G ..........................WHITE/GREENY/L ............................YELLOW/BLUEY/R............................YELLOW/REDL/B............................BLUE/BLACKL/W...........................BLUE/WHITEL/Y ............................BLUE/YELLOWR/Y............................RED/YELLOWL/G............................BLEU/GREEN

ELECTRICAL DIAGRAM YN50

yamaha neo's 50-service manual (02)

Documents

chapter symbol

inspection procedures

manual formatall procedures

danger symbol

disassemblyassembly

procedures inherent

procedures easierand

warningthis manual