Yamaha YJ125S Service Manual
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Yamaha YJ125S Service Manual

Yamaha YJ125S Service Manual

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YJ125S

SERVICE MANUAL

LIT-11616-17-43
5YR-28197-10

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Summary of Contents for Yamaha YJ125S

  • Page 1: Service Manual

    YJ125S SERVICE MANUAL LIT-11616-17-43 5YR-28197-10...
  • Page 2 EAS00000 YJ125S 2003 SERVICE MANUAL ©2003 by Yamaha Motor Taiwan Co., Ltd. First edition, November 2003 All rights reserved. Any reproduction or unauthorized use without the written permission of Yamaha Motor Taiwan Co., Ltd. is expressly prohibited. Printed in U.S.A.

  • Page 3: Specifications

    EAS00002 NOTICE This manual was produced by the Yamaha Motor Taiwan Company, Ltd. primarily for use by Yamaha dealers and their qualified mechanics. It is not possible to include all the knowledge of a mechanic in one manual. Therefore, anyone who uses this book to perform maintenance and repairs on Yamaha vehicles should have a basic understanding of mechanics and the techniques to repair these types of vehicles.

  • Page 4: Periodic Checks And

    HOW TO USE THIS MANUAL This manual is intended as a handy, easy-to-read reference book for the mechanic. Comprehensive explanations of all installation, removal, disassembly, assembly, repair and check procedures are laid out with the individual steps in sequential order. 1 The manual is divided into chapters.

  • Page 5: General Information

    EAS00008 SYMBOLS The following symbols are not relevant to every SPEC vehicle. INFO Symbols 1 to 9 indicate the subject of each chapter. 1 General information CHAS 2 Specifications 3 Periodic checks and adjustments 4 Chassis 5 Engine 6 Cooling system COOL 7 Carburetor(s) 8 Electrical system...

  • Page 6: Table Of Contents

    EAS00011 TABLE OF CONTENTS GENERAL INFORMATION INFO SPECIFICATIONS SPEC PERIODIC CHECKS AND ADJUSTMENTS CHASSIS CHAS ENGINE CARBURETOR CARB ELECTRICAL SYSTEM ELEC TROUBLESHOOTING TRBL SHTG...

  • Page 7: Gen Info

    INFO CHAPTER 1 GENERAL INFORMATION SCOOTER IDENTIFICATION ..............1-1 VEHICLE IDENTIFICATION NUMBER ..........1-1 MODEL LABEL .................. 1-1 IMPORTANT INFORMATION ..............1-2 PREPARATION FOR REMOVAL AND DISASSEMBLY ....1-2 REPLACEMENT PARTS ..............1-2 GASKETS, OIL SEALS AND O-RINGS ..........1-2 LOCK WASHERS/PLATES AND COTTER PINS ......

  • Page 8: Scooter Identification

    SCOOTER IDENTIFICATION INFO EAS00015 GENERAL INFORMATION SCOOTER IDENTIFICATION EAS00017 VEHICLE IDENTIFICATION NUMBER The vehicle identification number 1 is stamped into the steering head pipe. EAS00018 MODEL LABEL The model label 1 is affixed to the seat. This information will be needed to order spare parts.

  • Page 9: Important Information

    5. Keep all parts away from any source of fire. EAS00021 REPLACEMENT PARTS Use only genuine Yamaha parts for all replace- ments. Use oil and grease recommended by Yamaha for all lubrication jobs. Other brands may be similar in function and appearance, but infe- rior in quality.

  • Page 10: Lock Washers/Plates And Cotter Pins

    IMPORTANT INFORMATION INFO EAS00023 LOCK WASHERS/PLATES AND COTTER PINS After removal, replace all lock washers/plates 1 and cotter pins. After the bolt or nut has been tightened to specification, bend the lock tabs along a flat of the bolt or nut. EAS00024 BEARINGS AND OIL SEALS Install bearings and oil seals so that the...

  • Page 11: Checking The Connections

    CHECKING THE CONNECTIONS INFO EAS00026 CHECKING THE CONNECTIONS Check the leads, couplers, and connectors for stains, rust, moisture, etc. 1. Disconnect: 8 lead 8 coupler 8 connector 2. Check: 8 lead 8 coupler 8 connector Moisture Dry with an air blower. Rust/stains Connect and disconnect several times.
  • Page 12 SPECIAL TOOLS INFO EAS00027 SPECIAL TOOLS The following special tools are necessary for complete and accurate tune-up and assembly. Use only the appropriate special tools as this will help prevent damage caused by the use of inappropri- ate tools or improvised techniques. Special tools, part numbers or both may differ depending on the country.

  • Page 13: Special Tools

    SPECIAL TOOLS INFO Tool NO. Tool name / Function Illustration Fork seal driver weight 1 90890-01367 YM-A9409-7 Fork seal driver attachment(Ø30mm) 2 90890-01400 YM-A9409-3 This tool is used when installing the fork seal. 90890-01384 Oil seal guide YM-33299 This tool is used for protecting the oil seal lip when installing the secondary sliding sheave.
  • Page 14 Illustration 90890-06754 Ignition checker YM-34487 This instrument is necessary for checking the ignition system components. 90890-85505 Yamaha bond NO.1215 ACC-11001-05-01 This sealant (bond) is used for crankcase mating surface, etc. 80890-04116 Valve guide remover (4.5 mm) YM-04116 This tool is used to remove or install the valve guides.

  • Page 15: Spec

    SPEC CHAPTER 2 SPECIFICATIONS GENERAL SPECIFICATIONS ..............2-1 ENGINE SPECIFICATIONS ..............2-2 CHASSIS SPECIFICATIONS ..............2-11 ELECTRICAL SPECIFICATIONS ............2-14 CONVERTION TABLE / GENERAL TIGHTENING TORQUE SPECIFICA- TIONS ....................2-18 TIGHTENING TORQUES................ 2-19 ENGINE TIGHTENING TORQUES ..........2-19 CHASSIS TIGHTENING TORQUES ..........2-21 LUBRICATION POINTS AND LUBRICANT TYPES ......

  • Page 16: General Specifications

    SPEC GENERAL SPECIFICATIONS SPECIFICATIONS GENERAL SPECIFICATIONS Item Standard Limit Model code 5YR1 (for USA) … 5YR2 (for CAN) … Dimensions Overall length 1755 mm (69.1 in) … Overall width 699 mm (27.5 in) … Overall height 1063 mm (41.8 in) …...

  • Page 17: Engine Specifications

    Wet sump … Recommended oil SAE20W40SE … -20˚ -10˚ 0˚ 10˚ 20˚ 30˚ 40˚ 50˚ Yamaha 4-cycle oil … EFERO X, Z, BX SAE 10W-30 SAE 10W-40 SAE 20W-40 SAE 20W-50 Quantity Periodic oil change 1.0L(0.92 lmp qt, 1.09 US qt) …...
  • Page 18 SPEC ENGINE SPECIFICATIONS Standard Limit Item Oil filter Oil filter type Wire mesh … Oil pump Oil pump type Trochoid … Inner rotor to outer rotor tip clearance 0.15 mm 0.23mm Outer rotor to pump housing clearance 0.013-0.036 mm 0.106mm Oil pump housing to inner rotor and outer 0.06-0.10 mm 0.17mm...
  • Page 19 SPEC ENGINE SPECIFICATIONS Standard Limit Item Camshaft Drive system Chain drive (left) … Intake camshaft lobe dimensions Measurement A 26.153~26.253 mm 26.053 mm Measurement B 21.015~21.115 mm 20.915 mm Measurement C 5.203mm … Exhaust camshaft lobe dimensions Measurement A 26.153~26.253 mm 26.053 mm Measurement B 21.056~21.156 mm...
  • Page 20 SPEC ENGINE SPECIFICATIONS Standard Limit Item Timing chain Model/number of links Morse 92RH2005 / 88 … Tensioning system Automatic … Valve, valve seats, valve guides Valve clearance (cold) Intake 0.08~0.12 mm … Exhaust 0.13~0.17 mm … Valve dimensions Head Diameter Face Width Seat Width Margin Thickness...
  • Page 21 SPEC ENGINE SPECIFICATIONS Standard Limit Item Valve springs Free length Intake 37.30 mm 35.40 mm Exhaust 37.30 mm 35.40 mm Installed length (valve closed) Intake 25.77mm … Exhaust 25.77mm … Compressed spring force (installed) Intake 147±11N (15.0 ± 1.1 kgf/mm) …...
  • Page 22 SPEC ENGINE SPECIFICATIONS Standard Limit Item Piston Piston-to-cylinder clearance 0.010~0.030 mm 0.150mm Diameter D 51.470~51.510 mm … Height H 3.5 mm … Piston pin bore (in the piston) Diameter 13.002~13.013 mm 13.043 mm Offset 0.35~0.65mm … Offset direction Intake side …...
  • Page 23 SPEC ENGINE SPECIFICATIONS Standard Limit Item Rocker arm/rocker arm shaft Rocker arm inside diameter 10~10.015mm … Rocker arm shaft outside diameter 9.981~9.991 mm … Arm-to-shaft clearance 0.009~0.034 mm … Connecting rod Connecting rod length 97.95~98.05 mm … Small end inside diameter 13.015~13.028mm …...
  • Page 24 SPEC ENGINE SPECIFICATIONS Standard Limit Item Clutch Clutch type Automatic centrifugal … Clutch shoe thickness 3.4 ± 0.1 mm 2.0mm Clutch shoe spring free length 28.0 ± 0.4 mm … Clutch housing inside diameter 120 ± 0.1 mm 120.3mm Compression spring free length 113.6 mm …...
  • Page 25 SPEC ENGINE SPECIFICATIONS Standard Limit Item Throttle bodys Model (manufacturer) × quantity 5YR (SAFETY CONTROL … CABLE) × 2 Intake vacuum pressure 30.0kpa (238.6mmHg) … Throttle cable free play (at the flange of the 3~5mm … throttle grip) ID mark 5YR1 …...

  • Page 26: Chassis Specifications

    SPEC CHASSIS SPECIFICATIONS CHASSIS SPECIFICATIONS Standard Limit Item Frame Frame type Steel tube underbone … Caster angle 32 ° … Trail 75 mm … Front wheel Wheel type Cast wheel … Size 10 × MT2.15 … Material Aluminum … Wheel travel 59mm …...
  • Page 27 SPEC CHASSIS SPECIFICATIONS Standard Limit Item Front disc brake Brake type Single disc brake … Operation Right-hand operation … Brake lever free play (at lever end) 3~5mm … Recommended fluid DOT 4 … Brake disc Diameter x thickness 180.0 × 4.0 mm 180.0 ×...
  • Page 28 SPEC CHASSIS SPECIFICATIONS Standard Limit Item Rear drum brake Brake type Drum brake … Operation Left-hand operation … Brake lever free play (at lever end) 10~20mm … Brake drum inside diameter 110 mm 111mm Lining thickness 4.0mm Front suspension Suspension type Telescopic …...

  • Page 29: Electrical Specifications

    SPEC ELECTRICAL SPECIFICATIONS ELECTRICAL SPECIFICATIONS Standard Limit Item System voltage … Ignition system Ignition system type C.D.I. … Ignition timing (B.T.D.C.) 5 °/1650 r/min (IDL) … Advancer type Digital … 304~456 Ω / WR-WL Pickup coil resistance /color … C.D.I. unit model (manufacturer) 5YR00(T-MORIC) …...
  • Page 30 SPEC ELECTRICAL SPECIFICATIONS Standard Limit Item Bulbs (voltage/wattage × quantity) Headlight 12 V 60 W/55 W × 1 … Tail/brake light 12 V 8W/27 W × 1 … Front turn signal light 12 V 10 W × 2 … Rear turn signal light 12 V 10 W ×...
  • Page 31 SPEC ELECTRICAL SPECIFICATIONS Standard Limit Item Electric starting system System type Constant mesh … Starter motor Model (manufacturer) 4TE1 (T-MORIC) … Suction voltage … Power output 0.3 kW … Brushes Overall length 10.0 mm 3.5mm Quantity … Spring force 5.52~8.28 N …...
  • Page 32 SPEC ELECTRICAL SPECIFICATIONS Standard Limit Item Fuel lever meter Type( manufacturer ) Moving magneto (CHAO LONG) … Fuse (amperage × quantity) Main fuse 10A×1 … Reserve fuse 10A×1 … 2-17...

  • Page 33: Convertion Table / General Tightening Torque Specifica- Tions

    CONVERTION TABLE / GENERAL TIGHTENING SPEC TORQUE SPECIFICATIONS EB201000 EAS00030 CONVERSION TABLE GENERAL TIGHTENING TORQUE All specification data in this manual are listed SPECIFICATIONS in SI and METRIC UNITS. This chart specifies tightening torques for stan- Use this table to convert METRIC unit data to dard fasteners with a standard ISO thread IMPERIAL unit data.

  • Page 34: Tightening Torques

    SPEC TIGHTENING TORQUES ENGINE TIGHTENING TORQUES Tightening Thread Part to be tightened ’ Part name torque Remarks size Nm m•kgf ft•lb Cylinder head and cylinder 15.9 Spark plug 12.5 1.25 Cylinder head(timing chain side) Bolt Mainfold stud bolt Exhaust pipe stud bolt Breather assembly Bolt Stopper plate...
  • Page 35 SPEC TIGHTENING TORQUES Tightening Thread ’ Part to be tightened Part name torque Remarks size Nm m•kgf ft•lb Drain bolt(engine oil ) 16.6 V-belt case air filter element holder Screw Oil pipe Bolt Cylinder stud bolt (case1) 12.5 1.25 Cylinder stud bolt (case2) 12.5 1.25 Crankcase cover3...

  • Page 36: Chassis Tightening Torques

    SPEC TIGHTENING TORQUES CHASSIS TIGHTENING TORQUES Tightening Thread Part to be tightened torque Remarks size m•kgf ft•lb Frame and engine bracket 2 30.4 Engine bracket 2 and engine bracket 3 39.8 Engine bracket, engine and centerstand 23.1 Rear shock absorber and frame 21.7 Rear shock absorber and engine 13.0...

  • Page 37: Lubrication Points And Lubricant Types

    SPEC LUBRICATION POINTS AND LUBRICANT TYPES ENGINE LUBRICATION POINTS AND LUBRICANT TYPES Lubrication Point Lubricant Oil seal lips O-ring (Except V-belt drive unit) Cylinder head tightening nut mounting surface Cylinder head stud bolt thread Cylinder head gasket dowel pin Crankshaft pin outside surface Connecting rod Piston outside and ring groove Piston pin outside surface...
  • Page 38 SPEC LUBRICATION POINTS AND LUBRICANT TYPES Lubrication Point Lubricant Primary sheave inside, Collar, Solid bush, Secondary fixed inner surface BEL-RAY asembly lube Secondary sheave torque cam ditch BEL-RAY asembly lube Gasket (Cylinder head cover) Sealant Stopper guide (Cylinder head cover) Sealant Crankcase mating surfaces Sealant...

  • Page 39: Chassis Lubrication Points And Lubrication Types

    SPEC LUBRICATION POINTS AND LUBRICANT TYPES EAS00032 CHASSIS LUBRICATION POINTS AND LUBRICATION TYPES Lubrication Point Lubricant Front wheel oil seal lips Frame head pipe bearing (upper and lower) Frame head pipe dust seal lips ( lower) Tube guide (throttle grip) inner surface Brake lever and lever holder bolt sliding surface Sidestand and frame sliding surface Centerstand sliding surface and mounting bolt...

  • Page 40: Oil Flow Diagrams

    SPEC OIL FLOW DIAGRAMS OIL FLOW DIAGRAMS 1 Oil strainer 2 Oil pump 3 Oil filter 4 Oil delivery pipe 5 Oil delivery pipe union bolt 2-25...
  • Page 41 SPEC OIL FLOW DIAGRAMS 1 Connecting rod big end bearing 2-26...

  • Page 42: Cable Routing

    SPEC CABLE ROUTING a Rear brake cable F Clamp the wire harness, wire CABLE ROUTING s Speedometer lead positive lead and wire nega- 1 Turn signal relay d Auto choke lead tive lead to the frame, clamp 2 Main switch assembly A Fasten the wire harness, rear position to the white mark 3 Seat lock cable...
  • Page 43 SPEC CABLE ROUTING J Fasten the C.D.I. unit lead and wire harness to the frame with a plastic locking tie, point the band tip to up- per and the trunk surface. K Fasten the wire harness to the frame and cut the end to be shorter than 5mm.
  • Page 44 SPEC CABLE ROUTING 1 Lever holder assembly (left A Pass the speedometer cable H The filler cover and fuel over- side) left side the inner fender and flow hose into the spacer. 2 Rear brake cable I Pass the fuel overflow hose front fender hole.
  • Page 45 SPEC CABLE ROUTING 1 Seat lock cable C Pass the throttle cable, wire H Clamp the starter motor lead 2 Carburetor heater lead harness and rear brake and C.D.I. magneto lead. 3 Carburetor autochoke lead I Pass the fuel overflow hose cable under the frame cross 4 Starter switch lead tube.

  • Page 46: Chk Adj

    CHAPTER 3 PERIODIC CHECKS AND ADJUSTMENTS INTRODUCTION ..................3-1 PERIODIC MAINTENANCE CHART FOR THE EMISSION CONTROL SYSTEM ....................3-2 Periodic maintenance chart for the emission control system ... 3-2 GENERAL MAINTENANCE AND LUBRICATION CHART ....3-3 General maintenance and lubrication chart........3-3 COVER AND PANEL ................
  • Page 47 CLEANING THE AIR FILTER ELEMENT/CLEANING THE V-BELT CASE AIR FILTER ELEMENT ............... 3-26 CLEANING THE AIR FILTER ELEMENT ........3-26 CLEANING THE V-BELT CASE AIR FILTER ELEMENT ....3-26 CHECKING THE CARBURETOR JOINT AND INTAKE MANIFOLD .. 3-28 CHECKING THE CARBURETOR JOINT AND INTAKE MANIFOLD ...................
  • Page 48 LUBRICATING THE SIDESTAND/LUBRICATING THE CENTERSTAND ..................3-45 LUBRICATING THE SIDESTAND ........... 3-45 LUBRICATING THE CENTERSTAND ..........3-45 CHECKING AND CHARGING THE BATTERY ........3-46 ELECTRICAL SYSTEM ................. 3-46 CHECKING AND CHARGING THE BATTERY....... 3-46 CHECKING AND CHARGING THE BATTERY/ CHECKING THE FUSES ................ 3-52 CHECKING THE FUSES ..............

  • Page 49: Introduction

    The annual checks must be performed every year, except if a kilometer-based maintenance is performed instead. From 30,000 km, repeat the maintenance intervals starting from 6,000 km. Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools, data and technical skills.

  • Page 50: Periodic Maintenance Chart For The Emission Control System

    • Check the air cut-off valve, reed valve, and hose for damage. Air induction system • Replace any damaged. * Since these items require special tools, data and technical skills, have a Yamaha dealer perform the service. NOTE: From 10000 mi (16000 km) or 30 months, repeat the maintenance intervals starting from 2000 mi...

  • Page 51: General Maintenance And Lubrication Chart

    CHART EAU32121 General maintenance and lubrication chart * Since these items require special tools, data and technical skills, have a Yamaha dealer perform the service. NOTE: From 12000 mi (18000 km) or 36 months, repeat the maintenance intervals starting from 4000 mi (7000 km) or 12 months.

  • Page 52: Cover And Panel

    COVER AND PANEL COVER AND PANEL SEAT AND SIDE COVERS • • 23Nm(2.3m kg, 16.6 ft Order Job/Part Q’ty Remarks Removing the seat and side covers Remove the parts in the order listed. Seat Rear carrier Side cover( left ) Side cover( right ) Hook( left ) Hook( right )

  • Page 53: Footrest Board And Footrest Board Side Cover Mole

    COVER AND PANEL FOOTREST BOARD AND FOOTREST BOARD SIDE COVER MOLE Order Job/Part Q’ty Remarks Removing the footrest board and Remove the parts in the order listed. footrest board side cover mole Side covers( left and right ) Refer to “SEAT AND SIDE COVERS” Battery cover Battery negative(-) lead Battery positive(+) lead...

  • Page 54: Leg Shield 1 , 2

    COVER AND PANEL LEG SHIELD 1 , 2 Order Job/Part Q’ty Remarks Removing the leg shield 1,2 Remove the parts in the order listed. Footrest board Refer to “FOOTREST BOARD AND FOOTREST BOARD SIDE COVER MOLE” Headlight cover Headlight assembly Front turn signal light bracket Leg shield 1 Main switch cover...

  • Page 55: Adjusting The Valve Clearance

    ADJUSTING THE VALVE CLEARANCE EAS00049 ENGINE ADJUSTING THE VALVE CLEARANCE The following procedure applies to all of the valves. NOTE: 8 Valve clearance adjustment should be made on a cold engine, at room tempera- ture. 8 When the valve clearance is to be mea- sured or adjusted, the piston must be at top dead center (TDC) on the compression stroke.

  • Page 56: Adjusting The Valve Clearance

    ADJUSTING THE VALVE CLEARANCE ***************************************************** a. Turn the crankshaft counterclockwise. b. When the piston is at TDC on the compres- sion stroke, align the punch mark in the camshaft sprocket with the stationary on the cylinder head. c. Align the TDC mark 1 on the magneto ro- tor with the stationary pointer 2 on the crankcase.
  • Page 57 ADJUSTING THE VALVE CLEARANCE 5. Install: 8 cap 8 spark plug 12.5 Nm (1.25 m • kg, 9 ft • lb) 8 valve cover (exhaust ) 8 engine oil cap 6. Install: 8 spark plug cap 8 front cover 8 hook 8 side cover (right,left ) 8 rear carrier 8 cover...

  • Page 58: Adjusting The Engine Idling Speed

    ADJUSTING THE ENGINE IDLING SPEED EAS00054 ADJUSTING THE ENGINE IDLING SPEED NOTE: Prior to adjusting the engine idling speed, the air filter element should be clean, and the en- gine should have adequate compression. 1. Start the engine and let it warm up for sev- eral minutes.

  • Page 59: Checking The Exhaust Gas At Idle

    CHECKING THE EXHAUST GAS AT IDLE CHECKING THE EXHAUST GAS AT IDLE (Measuring the exhaust gas at idle[when air induction system is operation]) 1. Stand the scooter on a level surface. NOTE: 8 Place the scooter on a suitable stand. 8 Make sure the scooter is upright.
  • Page 60 CHECKING THE EXHAUST GAS AT IDLE NOTE: 8 Since it is necessary to insert the sampling probe 600mm into the exhaust pipe, be sure to use a heat-resisant rubber tube as shown in the illustration. 8 Be sure to set the heat-resistant rubber tube so that exhaust gas does not leak out.

  • Page 61: Adjusting The Throttle Cable Free Play

    ADJUSTING THE THROTTLE CABLE FREE PLAY EAS00057 ADJUSTING THE THROTTLE CABLE FREE PLAY NOTE: Prior to adjusting the throttle cable free play, the engine idling speed should be adjusted prop- erly. 1. Check: 8 throttle cable free play a Out of specification Adjust.
  • Page 62 ADJUSTING THE THROTTLE CABLE FREE PLAY Handlebar side a. Loosen the locknut 1. b. Turn the adjusting nut 2 in direction a or b until the specified throttle cable free play is obtained. Direction a Throttle cable free play is increased. Direction b Throttle cable free play is de- creased.

  • Page 63: Checking The Spark Plug

    CHECKING THE SPARK PLUG EAS00060 CHECKING THE SPARK PLUG 1. Remove: 8 cover Refer to “COVER AND PANEL”. 2. Disconnect: 8 spark plug cap 3. Remove: 8 spark plug Before removing the spark plug, blow away any dirt accumulated in the spark plug well with compressed air to prevent it from falling into the cylinder.

  • Page 64: Checking The Ignition Timing

    CHECKING THE IGNITION TIMING EAS00062 CHECKING THE IGNITION TIMING NOTE: Prior to checking the ignition timing, check the wiring connections of the entire ignition system. Make sure all connections are tight and free of corrosion. 1. Remove: cap 1 2. Attach: timing light engine tachometer (onto the spark plug lead of cylinder)

  • Page 65: Measuring The Compression Pressure

    MEASURING THE COMPRESSION PRESSURE EAS00067 MEASURING THE COMPRESSION PRES- SURE NOTE: Insufficient compression pressure will result in a loss of performance. 1. Measure: 8 valve clearance Out of specification Adjust Refer to “ADJUSTING THE VALVE CLEARANCE”. 2. Start the engine, warm it up for several min- utes, and then turn it off.
  • Page 66 MEASURING THE COMPRESSION PRESSURE 7. Measure: 8 compression pressure Out of specification Refer to steps (c) and (d). Compression pressure (at sea level) Minimum 827 kPa (8.27 kg/cm , 400r/min) Standard 950 kPa (9.5 kg/cm , 400r/min) Maximum 1064 kPa (10.64 kg/cm , 400r/min) ***************************************************** a.
  • Page 67 MEASURING THE COMPRESSION PRESSURE 11. Install: 8 front cover 8 hook 8 side cover (right,left ) 8 rear carrier 8 cover Refer to “COVER AND PANEL”. 3-19...

  • Page 68: Checking The Engine Oil Level

    CHECKING THE ENGINE OIL LEVEL EAS00069 CHECKING THE ENGINE OIL LEVEL 1. Stand the scooter on a level surface. NOTE: 8 Place the scooter on a suitable stand. 8 Make sure the scooter is upright. 2. Start the engine, warm it up for several min- utes, and then turn it off.

  • Page 69: Checking The Engine Oil

    CHECKING THE ENGINE OIL EAS00076 CHANGING THE ENGINE OIL 1. Start the engine, warm it up for several min- utes, and then turn it off. 2. Place a container under the engine oil drain bolt. 3. Remove: 8 engine oil filler cap 1 8 engine oil drain bolt 2 (along with the gasket) 4.

  • Page 70: Changing The Engine Oil Filter Element

    CHANGING THE ENGINE OIL FILTER ELEMENT 11. Check: 8 engine oil level Refer to “CHECKING THE ENGINE OIL LEVEL”. 12. Check: 8 engine oil pressure Refer to “CHECKING THE ENGINE OIL PRESSURE”. CHANGING THE ENGINE OIL FILTER ELE- MENT 1. Drain: 8 engine oil 2.
  • Page 71 CHANGING THE ENGINE OIL FILTER ELEMENT Check it under the condition that a check bolt is surely loosened because oil erupts when a check bolt is removed and an engine is started. 5. Fill: 8 crankcase Refer to “CHECKING THE ENGINE OIL “.

  • Page 72: Changing The Transmission Oil

    CHANGING THE TRANSMISSION OIL CHANGING THE TRANSMISSION OIL 1. Stand the scooter on a level surface. NOTE: 8 Stand the scooter on a suitable stand. 8 Make sure that the scooter up right. 2. Start the engine, warm it up for several min- utes, and then turn it off.

  • Page 73: Measuring The Engine Oil Pressure

    MEASURING THE ENGINE OIL PRESSURE EAS00077 MEASURING THE ENGINE OIL PRESSURE 1. Check: 8 engine oil level Below the minimum level mark Add the recommended engine oil to the proper level. Refer to “CHECKING THE ENGINE OIL LEVEL”. 2. Start the engine, warm it up for several min- utes, and then turn it off.

  • Page 74: Cleaning The Air Filter Element/Cleaning The V-Belt Case Air Filter Element

    CLEANING THE AIR FILTER ELEMENT/ CLEANING THE V-BELT CASE AIR FILTER ELEMENT EAS00086 CLEANING THE AIR FILTER ELEMENT 1. Remove: 8 air filter case cover 1 8 air filter element2 2. Check: 8 air filter element Damage Replace. EAS00091 CLEANING THE V-BELT CASE AIR FILTER ELEMENT 1.
  • Page 75 CLEANING THE V-BELT CASE AIR FILTER ELEMENT NOTE: After cleaning, gently squeeze the V-belt case air filter element to remove the excess solvent. Do not twist the V-belt case air filter element when squeezing it. 5. Apply the recommended oil to the entire surface of the air filter element and squeeze out the excess oil.

  • Page 76: Checking The Carburetor Joint And Intake Manifold

    CHECKING THE CARBURETOR JOINT AND INTAKE MANIFOLD EAS00094 CHECKING THE CARBURETOR JOINT AND INTAKE MANIFOLD 1. Remove: 8 cover 8 rear carrier 8 side cover (right,left ) 8 seat 8 hook 8 front cover 8 fuel tank cap 8 rear cover 8 trunk Refer to “COVER AND PANEL”.

  • Page 77: Checking The Fuel And Vacuum Hoses/Checking The Crankcase Breather Hose

    CHECKING THE FUEL AND VACUUM HOSES/ CHECKING THE CRANKCASE BREATHER HOSE EAS00096 CHECKING THE FUEL AND VACUUM HOSES The following procedure applies to all of the fuel and vacuum hoses. 1. Remove: 8cover 8rear carrier 8side cover (left ) Refer to “COVER AND PANEL”. 2.

  • Page 78: Checking The Exhaust System

    CHECKING THE EXHAUST SYSTEM EAS00099 CHECKING THE EXHAUST SYSTEM The following procedure applies to all of the muffler assembly and gaskets. 1. Remove: 8 hose(from air fi/ter) 8 vacuum hose 8 hose(to cylinder head) 8 air cut-off valve assembly Refer to “AIR INDUCTION SYSTEM”in chapter 6.

  • Page 79: Adjusting The Front Brake/Adjusting The Rear Brake

    ADJUSTING THE FRONT BRAKE/ ADJUSTING THE REAR BRAKE EAS00108 CHASSIS ADJUSTING THE FRONT BRAKE 1. Check: 8 brake lever free play a Brake lever free play (at the end of the brake lever) 3 ~ 5mm (0.12 ~ 0.20 in) A soft or spongy feeling in the brake lever can indicate the presence of air in the brake system.

  • Page 80: Checking The Brake Fluid Level

    CHECKING THE BRAKE FLUID LEVEL EAS00116 CHECKING THE BRAKE FLUID LEVEL 1. Stand the scooter on a level surface. NOTE: 8 Place the scooter on a suitable stand. 8 Make sure the scooter is upright. 2. Check: 8 brake fluid level Below the minimum level mark a the recommended brake fluid to the proper level.

  • Page 81: Checking The Front Brake Pads/ Checking The Rear Brake Shoes/Checking The Front Brake Hose

    CHECKING THE FRONT BRAKE PADS/ CHECKING THE REAR BRAKE SHOES/ CHECKING THE FRONT BRAKE HOSE EAS00117 CHECKING THE FRONT BRAKE PADS The following procedure applies to all of the brake pads. 1. Remove: 8 cap 1 2. Operate the brake. 3.

  • Page 82: Brake Fluid Change

    BRAKE FLUID CHANGE BRAKE FLUID CHANGE Should you feel loose when pulling Brake, it is possibly due to leaking of Brake fluid of mixing with air which led to the ineffectiveness of Brake. Since poor performance of Brake caused by mixing with air may trigger accidents, therefore inspection must be carried out prior to riding, and expel the air if necessary.
  • Page 83 BRAKE FLUID CHANGE e. Remove the reservoir diaphragm. f. Fill proper volume of designated brake fluid into the reservoir of the master cylinder. Refer to “CHECKING THE BRAKE FLUID LEVEL”. g. Operate brake lever slowly for several times. Repeat the procedures until the small amount of air (air bubbles) in the reservoir tank disappears, and the brake lever feels heavy.

  • Page 84: Bleeding The Hydraulic Brake System

    BLEEDING THE HYDRAULIC BRAKE SYSTEM EAS00133 BLEEDING THE HYDRAULIC BRAKE SYS- Bleed the hydraulic brake system whenever: 8 8 8 8 8 the system is disassembled. 8 8 8 8 8 a brake hose is loosened, disconnected or replaced. 8 8 8 8 8 the brake fluid level is very low. 8 8 8 8 8 brake operation is faulty.
  • Page 85 BLEEDING THE HYDRAULIC BRAKE SYSTEM h. Tighten the bleed screw and then release the brake lever. i. Repeat steps (e) to (h) until all of the air bubbles have disappeared from the brake fluid in the plastic hose. j. Tighten the bleed screw to specification. Bleed screw 6 Nm (0.6 m •...

  • Page 86: Checking And Adjusting The Steering Head

    CHECKING AND ADJUSTING THE STEERING HEAD EAS00148 CHECKING AND ADJUSTING THE STEER- ING HEAD 1. Stand the scooter on a level surface. Securely support the scooter so that there is no danger of it falling over. NOTE: Place the scooter on a suitable stand so that the front wheel is elevated.
  • Page 87 CHECKING AND ADJUSTING THE STEERING HEAD c. Loosen the lower ring nut completely and then tighten it to specification with a steer- ing nut wrench . Do not overtighten the lower ring nut. Lower ring nut (final tightening torque) 9 Nm (0.9 m • kg, 6.5 ft • lb) d.

  • Page 88: Checking The Front Fork

    CHECKING THE FRONT FORK EAS00151 CHECKING THE FRONT FORK 1. Stand the scooter on a level surface. Securely support the scooter so that there is no danger of it falling over. 2. Check: 8 inner tube Damage/scratches Replace. 8 oil seal Oil leakage Replace.

  • Page 89: Checking The Tires

    CHECKING THE TIRES EAS00163 CHECKING THE TIRES The following procedure applies to both of the tires. 1. Check: 8tire pressure Out of specification Regulate. 8 8 8 8 8 The tire pressure should only be checked and regulated when the tire temperature equals the ambient air tem- perature.
  • Page 90 No guarantee concerning han- dling characteristics can be given if a tire combination other than one ap- proved by Yamaha is used on this scooter. Front tire Manufacturer Model...
  • Page 91 CHECKING THE TIRES New tires have a relatively low grip on the road surface until they have been slightly worn. Therefore, approximately 100 km should be traveled at normal speed before any high-speed riding is done. NOTE: For tires with a direction of rotation mark 1: 8 Install the tire with the mark pointing in the direction of wheel rotation.

  • Page 92: Checking The Wheels/Checking And Lubricating The Cables

    CHECKING THE WHEELS/ CHECKING AND LUBRICATING THE CABLES EAS00168 CHECKING THE WHEELS The following procedure applies to both of the wheels. 1. Check: 8 wheel Damage/out-of-round Replace. Never attempt to make any repairs to the wheel. NOTE: After a tire or wheel has been changed or re- placed, always balance the wheel.

  • Page 93: Lubricating The Sidestand/Lubricating The Centerstand

    LUBRICATING THE SIDESTAND/ LUBRICATING THE CENTERSTAND EAS00172 LUBRICATING THE SIDESTAND Lubricate the pivoting point and metal-to-metal moving parts of the sidestand. Recommended lubricant Lithium-soap-based grease EAS00173 LUBRICATING THE CENTERSTAND Lubricate the pivoting point and metal-to-metal moving parts of the centerstand. Recommended lubricant Lithium-soap-based grease 3-45...

  • Page 94: Checking And Charging The Battery

    CHECKING AND CHARGING THE BATTERY EAS00179 ELECTRICAL SYSTEM CHECKING AND CHARGING THE BATTERY Batteries generate explosive hydrogen gas and contain electrolyte which is made of poisonous and highly caustic sulfuric acid. Therefore, always follow these preventive measures: 8 8 8 8 8 Wear protective eye gear when handling or working near batteries.

  • Page 95: Checking And Charging The Battery

    CHECKING AND CHARGING THE BATTERY NOTE: Since MF batteries are sealed, it is not possible to check the charge state of the battery by mea- suring the specific gravity of the electrolyte. Therefore, the charge of the battery has to be checked by measuring the voltage at the bat- tery terminals.

  • Page 96: Checking And Charging The Battery

    CHECKING AND CHARGING THE BATTERY b. Check the charge of the battery, as shown Relationship between the open-circuit voltage 13.0 and the charging time at 20 C in the charts and the following example. 12.5 Example 12.0 c. Open-circuit voltage = 12.0 V 11.5 d.
  • Page 97 CHECKING AND CHARGING THE BATTERY 8 8 8 8 8 Make sure the battery charger lead clips are in full contact with the battery ter- minal and that they are not shorted. A corroded battery charger lead clip may generate heat in the contact area and a weak clip spring may cause sparks.
  • Page 98 CHECKING AND CHARGING THE BATTERY Charging method using a variable-current (voltage) charger NOTE: Charger Measure the open-circuit Ammeter Leave the battery unused for more voltage prior to charging. than 30 minutes before measuring its opencircuit voltage. Connect a charger and am- NOTE: meter to the battery and Set the charging voltage to 16-17 V.
  • Page 99 CHECKING AND CHARGING THE BATTERY Charging method using a constant voltage charger Measure the open-circuit NOTE: voltage prior to charging. Leave the battery unused for more than 30 minutes before measuring its opencircuit voltage. Connect a charger and am- meter to the battery and start charging.

  • Page 100: Checking The Fuses

    CHECKING AND CHARGING THE BATTERY/ CHECKING THE FUSES 6. Install: 8 battery 7. Connect: 8 battery leads (to the battery terminals) First, connect the positive battery lead 1 1 1 1 1 , and then the negative battery lead 2 2 2 2 2 . 8.
  • Page 101 CHECKING THE FUSES 2. Check: 8 fuse ***************************************************** a. Connect the pocket tester to the fuse and check the continuity. NOTE: Set the pocket tester selector to “Ω × 1”. Pocket tester 90890-03132 (YU-03112-C) b. If the pocket tester indicates “∞”, replace the fuse.

  • Page 102: Replacing The Headlight Bulb

    REPLACING THE HEADLIGHT BULB EAS00182 REPLACING THE HEADLIGHT BULB 1. Remove: 8 headlight cover 2. Disconnect: 8 headlight coupler 1 3. Remove: 8 headlight bulb holder rubber2 4. Remove : 8 headlight bulb holder 1 8 headlight bulb 2 Since the headlight bulb gets extremely hot, keep flammable products and your hands away from the bulb until it has cooled down.

  • Page 103: Adjusting The Headlight Beams

    ADJUSTING THE HEADLIGHT BEAMS EAS00185 ADJUSTING THE HEADLIGHT BEAMS The following procedure applies to both of the headlight. 1. Adjust: 8 headlight beam (vertically) a. Loosen the adjusting screw 1and press headlight in direction a or b. ***************************************************** Direction a Headlight beam is raised.

  • Page 104: Chas

    CHAS CHAPTER 4 CHASSIS FRONT WHEEL AND BRAKE DISC ............4-1 FRONT WHEEL ................. 4-2 REMOVING THE FRONT WHEEL ............ 4-3 CHECKING THE FRONT WHEEL ............ 4-4 CHECKING THE BRAKE DISC ............4-5 ASSEMBLING THE FRONT WHEEL ..........4-7 INSTALLING THE FRONT WHEEL ..........4-8 ADJUSTING THE FRONT WHEEL STATIC BALANCE ....
  • Page 105 CHAS HANDLEBAR ..................4-43 REMOVING THE HANDLEBAR ............4-44 CHECKING THE HANDLEBAR ............4-44 INSTALLING THE HANDLEBAR............. 4-45 STEERING HEAD ................... 4-47 LOWER FENDER COVER AND HANDLEBAR LOWER HOLDER ..................4-47 LOWER BRACKET ................4-48 REMOVING THE LOWER BRACKET ..........4-50 CHECKING THE STEERING HEAD ..........

  • Page 106: Front Wheel And Brake Disc

    CHAS FRONT WHEEL AND BRAKE DISC EAS00513 CHASSIS FRONT WHEEL AND BRAKE DISC • • 70Nm(7.0m kg, 50.6 ft • • 20Nm(2.0m kg, 14.5 ft Order Job/Part Q’ty Remarks Removing the front wheel and brake Remove the parts in the order listed. disc NOTE: Place the scooter on a suitable stand so...

  • Page 107: Front Wheel

    CHAS FRONT WHEEL AND BRAKE DISC EAS00518 FRONT WHEEL Order Job/Part Q’ty Remarks Disassembling the front wheel Remove the parts in the order listed. Oil seal Bearing Collar Bearing Refer to”REMOVING THE FRONT WHEEL” and “INSTALLING THE FRONT WHEEL” For assembly, reverse the disassembly procedure.

  • Page 108: Removing The Front Wheel

    CHAS FRONT WHEEL AND BRAKE DISC EAS00520 REMOVING THE FRONT WHEEL 1. Stand the scooter on a level surface. Securely support the scooter so that there is no danger of it falling over. NOTE: Place the scooter on a suitable stand so that the front wheel is elevated.

  • Page 109: Checking The Front Wheel

    CHAS FRONT WHEEL AND BRAKE DISC EAS00525 CHECKING THE FRONT WHEEL 1. Check: 8 wheel axle Roll the wheel axle on a flat surface. Bends Replace. Do not attempt to straighten a bent wheel axle. 2. Check: 8 tire 8 front wheel Damage/wear Replace.

  • Page 110: Checking The Brake Disc

    CHAS FRONT WHEEL AND BRAKE DISC Clean the outside of the front wheel hub. Remove the oil seals 1 with a flat-head screwdriver. NOTE: To prevent damaging the wheel, place a rag 2 between the screwdriver and the wheel surface. c.
  • Page 111 CHAS FRONT WHEEL AND BRAKE DISC 3. Measure: 8 brake disc thicknessb Measure the brake disc thickness at a few different locations. Out of specification Replace. Brake disc thickness limit (mini- mum) 3.5 mm (0.14 in) 4. Adjust: 8 brake disc deflection ***************************************************** a.

  • Page 112: Assembling The Front Wheel

    CHAS FRONT WHEEL AND BRAKE DISC EAS00539 ASSEMBLING THE FRONT WHEEL 1. Install: 8 wheel bearings 8 oil seals ***************************************************** a. Install the new wheel bearings and oil seals in the reverse order of disassembly. Do not contact the wheel bearing inner race 1 1 1 1 1 or balls 2 2 2 2 2 .

  • Page 113: Installing The Front Wheel

    CHAS FRONT WHEEL AND BRAKE DISC EAS00542 INSTALLING THE FRONT WHEEL 1. Lubricate: 8 wheel axle 8 wheel bearings 8 oil seal lips Recommended lubricant Lithium-soap-based grease 2. Install: 8 speedometer gear unit 1 NOTE: Make sure the speedometer gear unit and the wheel hub are installed with the two projections 2meshed into the two slots3 respectively.

  • Page 114: Adjusting The Front Wheel Static Balance

    CHAS FRONT WHEEL AND BRAKE DISC EAS00548 ADJUSTING THE FRONT WHEEL STATIC BALANCE NOTE: 8 After replacing the tire, wheel or both, the front wheel static balance should be ad- justed. 8 Adjust the front wheel static balance with the brake disc installed. 1.
  • Page 115 CHAS FRONT WHEEL AND BRAKE DISC 3. Adjust: 8 front wheel static balance ***************************************************** a. Install a balancing weight 1 onto the rim exactly opposite the heavy spot “X”. NOTE: Start with the lightest weight. Turn the front wheel 90° so that the heavy spot is positioned as shown.

  • Page 116: Rear Wheel And Rear Brake

    CHAS REAR WHEEL AND REAR BRAKE REAR WHEEL AND REAR BRAKE • • 105Nm(10.5m kg, 75.9 ft Order Job/Part Q’ty Remarks Removing the rear wheel and rear Remove the parts in the order listed. brake NOTE: Place the scooter on a suitable stand so that the front wheel is elevated.

  • Page 117: Checking The Rear Wheel

    CHAS REAR WHEEL AND REAR BRAKE EAS00565 CHECKING THE REAR WHEEL 1. Check: 8 wheel axle 8 rear wheel Refer to “CHECKING THE FRONT WHEEL”. 2. Check: 8 tire 8 rear wheel Damage/wear Replace. Refer to “CHECKING THE TIRES” and “CHECKING THE WHEELS”...

  • Page 118: Checking The Brake

    CHAS REAR WHEEL AND REAR BRAKE EAS00569 CHECKING THE BRAKE The following procedure applies to all of the brake shoes. 1. Check: 8 brake shoe lining Glazed areas Repair. Sand the glazed areas with course sand- paper. NOTE: After sanding the glazed areas, clean the brake shoe with a cloth.

  • Page 119: Assembling The Brake Shoe Plate

    CHAS REAR WHEEL AND REAR BRAKE EAS00570 ASSEMBLING THE BRAKE SHOE PLATE 1. Install: 8 brake camshaft 1 8 brake shoe wear indicator 2 ***************************************************** Install the brake camshaft so its punch mark a is positioned as shown. Align the projection b on the brake shoe wear indicator with the notch in the brake shoe camshaft.

  • Page 120: Front Brake

    CHAS FRONT BRAKE EAS00576 FRONT BRAKE FRONT BRAKE PADS • • 35Nm(3.5m kg, 25.3 ft • • 22Nm(2.2m kg, 15.9 ft Order Job/Part Q’ty Remarks Removing the front brake pads Remove the parts in the order listed. Caliper brake bracket bolt Caliper brake pad bolt Brake pad Brake pad plate...

  • Page 121: Front Brake Pads

    CHAS FRONT BRAKE EAS00579 Disc brake components rarely require disassembly. Therefore, always follow these preventive measures: 8 8 8 8 8 Never disassemble brake components unless absolutely necessary. 8 8 8 8 8 If any connection on the hydraulic brake system is disconnected, the entire brake system must be disassembled, drained, cleaned, properly filled, and bled after...
  • Page 122 CHAS FRONT BRAKE 3. Remove: 8 brake pad bolt 8 brake pad spring 1 8 brake pads 2 8 brake pad plate 3 4. Measure: 8 brake pad wear limit a Out of specification Replace the brake pads as a set. Brake pad wear limit 0.8 mm(0.03 in) 5.
  • Page 123 CHAS FRONT BRAKE Lubricate: 8brake caliper guide bar Recommended lubricant Lithium-soap-based grease 8 8 8 8 8 Do not allow grease to contact the brake pads. 8 8 8 8 8 Remove any excess grease. 7. Install: 8brake pad bolt 22 Nm (2.2 m •...

  • Page 124: Front Brake Master Cylinder

    CHAS FRONT BRAKE EAS00584 FRONT BRAKE MASTER CYLINDER • • 9Nm(0.9m kg, 6.5 ft • • 1.6Nm(0.16m kg, 1.2 ft • • 26Nm(2.6m kg, 18.8 ft Order Job/Part Q’ty Remarks Removing the front brake master cyl- Remove the parts in the order listed. inder Brake fluid Drain.

  • Page 125: Disassembing The Front Brake Master Cylinder

    CHAS FRONT BRAKE EAS00585 DISASSEMBING THE FRONT BRAKE MASTER CYLINDER Order Job/Part Q’ty Remarks Disassembling the front brake mas- Remove the parts in the order listed. ter cylinder Reservoir diaphragm Dust boot Circlip / Washer Master cylinder kit Spring For assembly, reverse the disassembly procedure.

  • Page 126: Checking The Front Brake Master Cylinder

    CHAS FRONT BRAKE EAS00588 DISASSEMBLING THE FRONT BRAKE MAS- TER CYLINDER NOTE: Before disassembling the front brake master cylinder, drain the brake fluid from the entire brake system. 1. Disconnect: 8 brake switch coupler (from the brake switch) 2. Remove: 8 union bolt 1 8 copper washer 2 8 brake hose 3...
  • Page 127 CHAS FRONT BRAKE 3. Check: 8 brake master cylinder reservoir Cracks/damage Replace. brake master cylinder reservoir diaphragm Damage/wear Replace. 4. Check: brake hoses 1 Cracks/damage/wear Replace. 4-22...

  • Page 128: Assembling And Installing The Front Brake Master Cylinder

    CHAS FRONT BRAKE EAS00597 ASSEMBLING AND INSTALLING THE FRONT BRAKE MASTER CYLINDER 8 8 8 8 8 Before installation, all internal brake components should be cleaned and lu- bricated with clean or new brake fluid. 8 8 8 8 8 Never use solvents on internal brake components.
  • Page 129 CHAS FRONT BRAKE 5. Install: 8 copper washers1 8 brake hose2 8 union bolt3 26 Nm (2.6 m • kg, 18.8 ft • lb) Proper brake hose routing is essential to insure safe scooter operation. Refer to “CABLE ROUTING”. NOTE: 8 While holding the brake hose, tighten the union bolt as shown.
  • Page 130 CHAS FRONT BRAKE 7. Bleed: 8 brake system Refer to “BLEEDING THE HYDRAULIC BRAKE SYSTEM” in chapter 3. 8. Check: 8 brake fluid level Below the MIN level mark a Add the recommended brake fluid to the proper level. Refer to “CHECKING THE BRAKE FLUID LEVEL”...

  • Page 131: Front Brake Caliper

    CHAS FRONT BRAKE EAS00612 FRONT BRAKE CALIPER • • 35Nm(3.5m kg, 25.3 ft • • 23Nm(2.3m kg, 16.6 ft Order Job/Part Q’ty Remarks Removing the front brake caliper Remove the parts in the order listed. Brake fluid Drain. Union bolt Copper washer Brake hose Front brake caliper bracket bolt...

  • Page 132: Disassembing The Front Brake Caliper

    CHAS FRONT BRAKE EAS00614 DISASSEMBING THE FRONT BRAKE CALIPER • • 6Nm(0.6m kg, 4.3 ft • • 22Nm(2.2m kg, 15.9 ft Order Job/Part Q’ty Remarks Disassembling the front brake cali- Remove the parts in the order listed. Caliper bracket Brake pad Brake pad plate Brake spring Dust seal...
  • Page 133 CHAS FRONT BRAKE EAS00619 DISASSEMBLING THE FRONT BRAKE CALI- NOTE: Before disassembling the brake caliper, drain the brake fluid from the entire brake system. 1. Remove: 8 union bolt 1 8 copper washers 2 8 brake hose 3 8 brake caliper pad bolt 4 8 brake caliper bracket bolts 5 8 brake caliper assembly6 NOTE:...

  • Page 134: Checking The Front Brake Caliper

    CHAS FRONT BRAKE EAS00631 CHECKING THE FRONT BRAKE CALIPER Recommended brake component replacement schedule Brake pads If necessary Piston seal Every 2 years Brake fluid Every 2 year and whenever the brake is disassembled 1. Check: 8 brake caliper piston 1 Rust/scratches/wear Replace the brake caliper piston assembly.

  • Page 135: Assembling And Installing The Front Brake Caliper

    CHAS FRONT BRAKE EAS00637 ASSEMBLING AND INSTALLING THE FRONT BRAKE CALIPER 8 8 8 8 8 Before installation, all internal brake components should be cleaned and lu- bricated with clean or new brake fluid. 8 8 8 8 8 Never use solvents on internal brake components as they will cause the pis- ton seals to swell and distort.
  • Page 136 CHAS FRONT BRAKE 8brake caliper pad bolt 3 22 Nm (2.2 m • kg, 15.9 ft • lb) 8brake hose 4 8copper washers 5 8union bolt 6 23 Nm (2.3 m • kg, 16.6 ft • lb) Proper brake hose routing is essential to insure safe scooter operation.
  • Page 137 CHAS FRONT BRAKE ter will significantly lower the boiling point of the brake fluid and could cause vapor lock. Brake fluid may damage painted surfaces and plastic parts. Therefore, always clean up any spilt brake fluid immediately. 5. Bleed: 8 brake system Refer to “BLEEDING THE HYDRAULIC BRAKE SYSTEM”...

  • Page 138: Front Fork

    CHAS FRONT FORK EAS00646 FRONT FORK • • 45Nm(4.5m kg, 32.5 ft • • 23Nm(2.3m kg, 16.6 ft Order Job/Part Q’ty Remarks Removing the front fork legs Remove the parts in the order listed. Front wheel Refer to “FRONT WHEEL AND BRAKE DISC”.

  • Page 139: Disassembing The Front Fork Legs

    CHAS FRONT FORK EAS00648 DISASSEMBING THE FRONT FORK LEGS • • 30Nm(3.0m kg, 21.7 ft Order Job/Part Q’ty Remarks Disassembling the front fork legs Remove the parts in the order listed. Fork oil Drain. Fork spring Clamp / Boot Damper rod bolt / Gasket Inner tube Damper rod Rebound spring...

  • Page 140: Removing The Front Fork Legs

    CHAS FRONT FORK EAS00651 REMOVING THE FRONT FORK LEGS The following procedure applies to both of the front fork legs. 1. Stand the scooter on a level surface. Securely support the scooter so that there is no danger of it falling over. NOTE: Place the scooter on a suitable stand so that the front wheel is elevated.

  • Page 141: Disassembling The Front Fork Legs

    CHAS FRONT FORK EAS00653 DISASSEMBLING THE FRONT FORK LEGS The following procedure applies to both of the front fork legs. 1. Remove: 8fork spring 1 2. Drain: 8fork oil 3. Remove: 8damper rod assembly bolt 1 8damper rod assembly NOTE: While holding the damper rod with the damper rod holder 2 and T- handle3, loosen the damper rod assembly bolt.
  • Page 142 CHAS FRONT FORK 5. Remove: 8oil seal clip 1 (with a flat-head screwdriver) Do not scratch the inner tube. 6. Remove: 8oil seal 1 Never reuse the oil seal. 8 Rag 2 4-37...

  • Page 143: Checking The Front Fork Legs

    CHAS FRONT FORK EAS00656 CHECKING THE FRONT FORK LEGS The following procedure applies to both of the front fork legs. 1. Check: 8 inner tube 1 8 outer tube 2 Bends/damage/scratches Replace. Do not attempt to straighten a bent inner tube as this may dangerously weaken it.

  • Page 144: Assembling The Front Fork Legs

    CHAS FRONT FORK EAS00658 ASSEMBLING THE FRONT FORK LEGS The following procedure applies to both of the front fork legs. 8 8 8 8 8 Make sure the oil levels in both front fork legs are equal. 8 8 8 8 8 Uneven oil levels can result in poor han- dling and a loss of stability.
  • Page 145 CHAS FRONT FORK Damper rod holder 90890-01294(YM-01300-1) T-handle 90890-01326(YM-01326) 4. Install: 8oil seal 1 (with the fork seal driver weight 2 and adapter 3) Fork seal driver weight 90890-01367(YM-A9409-7) Adapter 90890-01400(YM-A9409-3) Make sure the numbered side of the oil seal faces up.
  • Page 146 CHAS FRONT FORK 6. Install: 8fork boot 1 7. Fill: 8 front fork leg (with the specified amount of the recom- mended fork oil) Quantity (each front fork leg) 0.126 L (0.11 lmp qt, 0.13 US qt) Recommended oil Fork oil 10W or equivalent NOTE: 8 While filling the front fork leg, keep it up- right.

  • Page 147: Installing The Front Fork Legs

    CHAS FRONT FORK EAS00663 INSTALLING THE FRONT FORK LEGS The following procedure applies to both of the front fork legs. 1. Install: 8front fork leg NOTE: Pull up the inner tube until it stops, then install the cap bolt. 2. Tighten: 8cap bolt 1 45 Nm (4.5 m •...

  • Page 148: Handlebar

    CHAS HANDLEBAR EAS00664 HANDLEBAR • • 9Nm(0.89m kg, 6.5 ft • • 30Nm(3.0m kg, 21.7 ft Order Job/Part Q’ty Remarks Removing the handlebar Remove the parts in the order listed. Rear view mirror ( left and right ) Brake master cylinder bracket Brake master cylinder assembly Handlebar switch assembly (right) Throttle cable...

  • Page 149: Removing The Handlebar

    CHAS HANDLEBAR EAS00666 REMOVING THE HANDLEBAR 1. Stand the scooter on a level surface. Securely support the scooter so that there is no danger of it falling over. 2. Remove: 8handlebar switch assembly (right)1 8throttle grip assembly 2 8brake master cylinder assembly 3 NOTE: While removing the handlebar switch assembly (right), pull back the rubber cover.

  • Page 150: Installing The Handlebar

    CHAS HANDLEBAR EAS00671 INSTALLING THE HANDLEBAR 1. Stand the scooter on a level surface. Securely support the scooter so that there is no danger of it falling over. 2. Install: 8 handlebar 1 8 upper handlebar holders 2 30 Nm (3.0 m • kg, 21.7 ft • lb) 8 8 8 8 8 First, tighten the bolts on the front side of the handlebar holder, and then on the rear side.
  • Page 151 CHAS HANDLEBAR 4. Install: 8 left handlebar switch 1 NOTE: Align the projection a on the left handlebar switch with the hole b in the handlebar. 5. Install: 8 throttle grip 1 8 right handlebar switch2 8 throttle cables 3 NOTE: 8 Lubricate the inside of the throttle grip with a thin coat of lithium-soap-based grease...

  • Page 152: Steering Head

    CHAS STEERING HEAD EAS00675 STEERING HEAD LOWER FENDER COVER AND HANDLEBAR LOWER HOLDER • • 47.5Nm(4.75m kg, 34.4 ft Order Job/Part Q’ty Remarks Removing the lower fender cover and Remove the parts in the order listed. handlebar lower holder Front wheel Refer to “FRONT WHEEL AND BRAKE DISC”.

  • Page 153: Lower Bracket

    CHAS STEERING HEAD EAS00675 LOWER BRACKET • • 60Nm(6.0m kg, 43.4 ft • • 75Nm(7.5m kg, 54.2 ft • • 28Nm(2.8m kg, 20.3 ft • • 2nd 9Nm(0.9m kg, 6.5 ft Order Job/Part Q’ty Remarks Removing the lower bracket Remove the parts in the order listed. Front wheel Refer to “FRONT WHEEL AND BRAKE DISC”.
  • Page 154 CHAS STEERING HEAD • • 60Nm(6.0m kg, 43.4 ft • • 75Nm(7.5m kg, 54.2 ft • • 28Nm(2.8m kg, 20.3 ft 2nd 9Nm(0.9m • • kg, 6.5 ft Order Job/Part Q’ty Remarks Rubber washer For installation, reverse the removal pro- cedure.

  • Page 155: Removing The Lower Bracket

    CHAS STEERING HEAD EAS00678 REMOVING THE LOWER BRACKET 1. Stand the scooter on a level surface. Securely support the scooter so that there is no danger of it falling over. 2. Remove: 8 handlebar holder bracket 1 NOTE: 8 Remove the handlebar holder bracket by loosening the upper ring nut2 gradually.

  • Page 156: Checking The Steering Head

    CHAS STEERING HEAD EAS00682 CHECKING THE STEERING HEAD 1. Wash: 8bearings 8bearing races Recommended cleaning solvent Kerosene 2. Check: 8bearings 1 8bearing races 2 Damage/pitting Replace. 3. Replace: 8bearings 8bearing races ***************************************************** a. Remove the bearing races from the steer- ing head pipe with a long rod 1 and ham- mer.

  • Page 157: Installing The Steering Head

    CHAS STEERING HEAD EAS00684 INSTALLING THE STEERING HEAD 1. Lubricate: 8 upper bearing 8 lower bearing 8 bearing races Recommended lubricant Lithium-soap-based grease 2. Install: 8 lower ring nut 1 8 rubber washer 2 8 center ring nut 3 8 lock washer 4 8 upper ring nut 5 Refer to “CHECKING THE STEERING HEAD”...

  • Page 158: Rear Shock Absorber

    CHAS REAR SHOCK ABSORBER EAS00692 REMOVING THE REAR SHOCK ABSORBER ASSEMBLY 1. Stand the scooter on a level surface. Securely support the scooter so that there is no danger of it falling over. NOTE: Place the scooter on a suitable stand so that the rear wheel is elevated.

  • Page 159: Installing The Rear Shock Absorber Assembly

    CHAS REAR SHOCK ABSORBER EAS00698 INSTALLING THE REAR SHOCK ABSORBER ASSEMBLY 1. Lubricate: 8 spacer 8 bush Recommended lubricant Molybdenum disulfide grease 2. Install: 8 rear shock absorber assembly 3. Tighten: 8 rear shock absorber assembly upper nut1 30 Nm (3.0 m • kg, 21.7 ft • lb) 8 rear shock absorber assembly lower bolt2 18 Nm (1.8 m •...

  • Page 160: Eng

    CHAPTER 5 ENGINE ENGINE ..................... 5-1 LEADS, HOSES AND REAR BRAKE ..........5-1 INSTALLING THE ENGINE ............... 5-3 MAINFOLD, AIR FILTER AND MUFFLER ASSEMBLY ....5-4 CYLINDER HEAD ..................5-5 CYLINDER HEAD ................5-5 REMOVING THE CYLINDER HEAD..........5-7 CHECKING THE CYLINDER HEAD ..........5-9 INSTALLING THE CYLINDER HEAD ..........
  • Page 161 BELT DRIVE.................... 5-35 CRANKCASE COVER ..............5-35 KICKSTARTER ................5-36 INSTALLING THE KICKSTARTER ..........5-37 V-BELT, CLUTCH, PRIMARY AND SECONDARY SHEAVE ..5-38 DISASSEMBLING THE SECONDARY SHEAVE ......5-39 REMOVING THE PRIMARY SHEAVE ..........5-40 REMOVING THE SECONDARY SHEAVE AND V-BELT....5-40 DISASSEMBLING THE SECONDARY SHEAVE ......

  • Page 162: Engine

    ENGINE EAS00188 ENGINE ENGINE LEADS, HOSES AND REAR BRAKE • • 18Nm(1.8m kg, 13.0 ft • • 42Nm(4.2m kg, 30.4 ft Order Job/Part Q’ty Remarks Removing the leads, hoses and rear Remove the parts in the order listed. brake Seat/Rear carrier Side cover ( left / right )/Fuel tank cap Refer to “COVER AND PANEL”in chap- Rear cover/Hook( left and right )
  • Page 163 ENGINE • • 18Nm(1.8m kg, 13.0 ft • • 42Nm(4.2m kg, 30.4 ft Order Job/Part Q’ty Remarks For installation, reverse the removal pro- cedure.

  • Page 164: Installing The Engine

    ENGINE NOTE: Make sure to reset the oil change indicator when the oil is changed. EAS00192 INSTALLING THE ENGINE 1. Install: 8 engine bracket bolt 1 NOTE: Do not fully tighten the bolts. 2. Tighten: 8 engine bracket bolt1 55Nm(5.5 m • kg, 39.8 ft • lb) 8 engine...

  • Page 165: Mainfold, Air Filter And Muffler Assembly

    ENGINE MAINFOLD, AIR FILTER AND MUFFLER ASSEMBLY • • 7Nm(0.7m kg, 5.1 ft • • 31Nm(3.1m kg, 22.4 ft • • 10Nm(1.0m kg, 7.2 ft Order Job/Part Q’ty Remarks Removing the mainfold, air filter and Remove the parts in the order listed. muffler assembly Starting motor lead / Earth lead Auto choke lead...

  • Page 166: Cylinder Head

    CYLINDER HEAD EAS00221 CYLINDER HEAD • • 8Nm(0.8m kg, 5.8 ft • • 8Nm(0.8m kg, 5.8 ft • • 10Nm(1.0m kg, 7.2 ft • • 10Nm(1.0m kg,7.2 ft • • 30Nm(3.0m kg, 21.7 ft • • 12Nm(1.2m kg, 8.7 ft •...
  • Page 167 CYLINDER HEAD • • 8Nm(0.8m kg, 5.8 ft • • 8Nm(0.8m kg, 5.8 ft • • 10Nm(1.0m kg, 7.2 ft • • 10Nm(1.0m kg,7.2 ft • • 30Nm(3.0m kg, 21.7 ft • • 12Nm(1.2m kg, 8.7 ft • • 22Nm(2.2m kg, 15.9 ft Order Job/Part...

  • Page 168: Removing The Cylinder Head

    CYLINDER HEAD EAS00225 REMOVING THE CYLINDER HEAD 1. Remove : 8 oil delivery pipe 8 engine oil cap 8 valve cover 8 Air shroud 1 8 Air shroud 2 8 breather 2. Align: 8 “I” mark a on the magneto (with the stationary pointer b on the crankcase cover) *****************************************************...
  • Page 169 CYLINDER HEAD NOTE: 8 To prevent the timing chain from falling into the crankcase, fasten it with a wire. 8 While holding the C.D.I. magneto bolt with a wrench, remove the camshaft sprocket plate bolt 1. 5. Remove: 8cylinder head NOTE: 8 Loosen the nuts in the proper sequence as shown.

  • Page 170: Checking The Cylinder Head

    CYLINDER HEAD EAS00227 CHECKING THE CYLINDER HEAD 1. Eliminate: 8 combustion chamber carbon deposits (with a rounded scraper) NOTE: Do not use a sharp instrument to avoid damag- ing or scratching: 8 spark plug bore thread 8 valve seats 2. Check: 8 cylinder head Damage/scratches Replace.

  • Page 171: Installing The Cylinder Head

    CYLINDER HEAD EAS00231 INSTALLING THE CYLINDER HEAD 1. Install: 8 gasket 8 dowel pins 2. Install: 8 cylinder head 3. Tighten: 8 cylinder head nuts 22 Nm (2.2 m • kg, 15.9 ft • lb) 8 cylinder head bolts 12 Nm (1.2 m • kg, 8.7 ft • lb) NOTE: 8 Lubricate the cylinder head nuts with en- gine oil.
  • Page 172 CYLINDER HEAD Do not turn the crankshaft when installing the camshaft to avoid damage or improper valve timing. e. While holding the camshaft, temporarily tighten the camshaft sprocket bolts. f. Remove the wire from the timing chain. ***************************************************** 5. Install 8camshaft sprocket plate 1 8camshaft sprocket plate bolt 2 6.
  • Page 173 CYLINDER HEAD 7. Turn: 8crankshaft (several turns counterclockwise) 8. Check: 8“I” mark a Align the “I” mark on the C.D.I. magneto rotor with the stationary pointer b on the crankcase cover. 8“I” mark c Align the “I” mark on the camshaft sprocket with the stationary pointer d on the cylinder head.

  • Page 174: The Rocker Arms And Camshaft

    THE ROCKER ARMS AND CAMSHAFT THE ROCKER ARMS AND CAMSHAFT • • 7Nm(0.7m kg, 5.1 ft • • 7Nm(0.7m kg, 5.1 ft Order Job/Part Q’ty Remarks Removing the rocker arms and cam- Remove the parts in the order listed. shaft Cylinder head Refer to “CYLINDER HEAD”.

  • Page 175: Removing The Rocker Arms And Camshaft

    THE ROCKER ARMS AND CAMSHAFT EAS00202 REMOVING THE ROCKER ARMS AND CAM- SHAFT 1. Remove: 8 locknut 1 8 stopper plate 2 2. Remove: 8 intake rocker arm shaft 8 exhaust rocker arm shaft 8 intake rocker arm 8 exhaust rocker arm NOTE: Remove the rocker arm shafts with the slide hammer bolt 1 and weight2 .
  • Page 176 THE ROCKER ARMS AND CAMSHAFT EAS00206 CHECKING THE ROCKER ARMS AND ROCKER ARM SHAFTS The following procedure applies to all of the rocker arms and rocker arm shafts. 1. Check: 8 rocker arm Damage/wear Replace. 2. Check: 8 rocker arm shaft Blue discoloration/excessive wear/pitting/ scratches Replace or check the lubri-...

  • Page 177: Checking The Camshaft

    THE ROCKER ARMS AND CAMSHAFT Rocker-arm-to-rocker-arm-shaft clearance 0.009 ~ 0.034 mm(0.0004~0.001 in) EAS00205 CHECKING THE CAMSHAFT 1. Check: 8 camshaft bushings Damage/wear Replace. 2. Check: 8 camshaft lobes Blue discoloration/pitting/scratches Replace the camshaft. 3. Measure: 8 camshaft lobe dimensions a and b Out of specification Replace the cam- shaft.

  • Page 178: Checking The Timing Chain, Camshaft Sprockets, And Timing Chain Guides

    THE ROCKER ARMS AND CAMSHAFT EAS00208 CHECKING THE TIMING CHAIN, CAMSHAFT SPROCKETS, AND TIMING CHAIN GUIDES The following procedure applies to all of the cam- shaft sprockets and timing chain guides. 1. Check: 8 timing chain 1 Damage/stiffness Replace the timing chain and camshaft sprockets as a set.

  • Page 179: Installing The Camshaft And Rocker Arms

    THE ROCKER ARMS AND CAMSHAFT EAS00220 INSTALLING THE CAMSHAFT AND ROCKER ARMS 1. Lubricate: 8 camshaft 1 Recommended lubricant Camshaft Molybdenum disulfide oil Camshaft bearing Engine oil 2. Lubricate: 8 rocker arm shafts Recommended lubricant Molybdenum disulfide oil 3. Install: 8 exhaust rocker arm 1 8 exhaust rocker arm shaft 2 NOTE:...

  • Page 180: Valves And Valve Springs

    VALVES AND VALVE SPRINGS EAS00236 VALVES AND VALVE SPRINGS Order Job/Part Q’ty Remarks Removing the valves and valve Remove the parts in the order listed. springs Cylinder head Refer to “CYLINDER HEAD”. Rocker arm and rocker arm shaft Refer to “ ROCKER ARMS AND ROCKER ARMS SHAFTS”.

  • Page 181: Removing The Valves

    VALVES AND VALVE SPRINGS EAS00237 REMOVING THE VALVES The following procedure applies to all of the valves and related components. NOTE: Before removing the internal parts of the cylin- der head (e.g., valves, valve springs, valve seats), make sure the valves properly seal. 1.

  • Page 182: Checking The Valves And Valve Guides

    VALVES AND VALVE SPRINGS 3. Remove: 8 valve cotter 1 8 valve spring retainer 2 8 valve spring 3 8 valve stem seal 4 8 lower spring seat 5 8 valve 6 NOTE: Identify the position of each part very carefully so that it can be reinstalled in its original place.
  • Page 183 VALVES AND VALVE SPRINGS NOTE: After replacing the valve guide, reface the valve seat. Valve guide remover (4.5 mm) 90890-04116 (YM-04116) Valve guide installer (4.5 mm) 90890-04117 (YM-04117) Valve guide reamer (5.0 mm) 90890-04099 ***************************************************** 3. Eliminate: 8 carbon deposits (from the valve face and valve seat) 4.

  • Page 184: Checking The Valve Seats

    VALVES AND VALVE SPRINGS EAS00240 CHECKING THE VALVE SEATS The following procedure applies to all of the valves and valve seats. 1. Eliminate: 8 carbon deposits (from the valve face and valve seat) 2. Check: 8 valve seat Pitting/wear Replace the cylinder head. 3.
  • Page 185 VALVES AND VALVE SPRINGS a. Apply a coarse lapping compound a to the valve face. Do not let the lapping compound enter the gap between the valve stem and the valve guide. b. Apply molybdenum disulfide oil onto the valve stem. c.

  • Page 186: Checking The Valve Springs

    VALVES AND VALVE SPRINGS EAS00241 CHECKING THE VALVE SPRINGS The following procedure applies to all of the valve springs. 1. Measure: 8 valve spring free length a Out of specification Replace the valve spring. Valve spring free length 37.30 mm(1.469 in) <Limit>: 35.40 mm(1.394 in) 2.

  • Page 187: Installing The Valves

    VALVES AND VALVE SPRINGS EAS00245 INSTALLING THE VALVES The following procedure applies to all of the valves and related components. 1. Deburr: 8valve stem end (with an oil stone) 2. Lubricate: 8valve stem 8valve stem seal (with the recommended lubricant) Recommended lubricant Molybdenum disulfide oil 3.
  • Page 188 VALVES AND VALVE SPRINGS Valve spring compressor 90890-04109 (YM-04109) Valve spring compressor attach- ment 90890-04108 (YM-04108) 5. To secure the valve cotters onto the valve stem, lightly tap the valve tip with a soft- face hammer. Hitting the valve tip with excessive force could damage the valve.

  • Page 189: Cylinder And Piston

    CYLINDER AND PISTON EAS00251 CYLINDER AND PISTON • • 12Nm(1.2m kg, 8.7 ft Order Job/Part Q’ty Remarks Removing the cylinder and piston Remove the parts in the order listed. Cylinder head Refer to “CYLINDER HEAD”. Clamp Pipe Timing chain guide (exhaust side) Cylinder O-ring Dowel pin...

  • Page 190: Removing The Cylinder And Piston

    CYLINDER AND PISTON EAS00253 REMOVING THE CYLINDER AND PISTON 1. Remove: 8 piston pin clip 1 8 piston pin 2 8 piston 3 Do not use a hammer to drive the piston pin out. NOTE: 8 Before removing the piston pin clip, cover the crankcase opening with a clean rag to prevent the piston pin clip from falling into the crankcase.

  • Page 191: Checking The Cylinder And Piston

    CYLINDER AND PISTON EAS00261* CHECKING THE CYLINDER AND PISTON 1. Check: 8 piston wall 8 cylinder wall Vertical scratches Replace the cylin- der, and the piston and piston rings as a set. 2. Measure: 8 piston-to-cylinder clearance ***************************************************** a. Please carry out the following inspections: 8 cylinder Measure the piston pin in both of its hori- zontal axis direction a and its right angle...

  • Page 192: Checking The Piston Rings

    CYLINDER AND PISTON EAS00263 CHECKING THE PISTON RINGS 1. Measure: 8 piston ring side clearance Out of specification Replace the pis- ton and piston rings as a set. NOTE: Before measuring the piston ring side clearance, eliminate any carbon deposits from the piston ring grooves and piston rings.

  • Page 193: Checking The Piston Pin

    CYLINDER AND PISTON EAS00265 CHECKING THE PISTON PIN 1. Check: 8 piston pin Blue discoloration/grooves Replace the piston pin and then check the lubrication system. 2. Measure: 8 piston pin outside diameter a Out of specification Replace the pis- ton pin. Piston pin outside diameter 12.996 ~ 13.000 mm (0.5117~0.5118 in)

  • Page 194: Checking The Timing Chain Guide

    CYLINDER AND PISTON CHECKING THE TIMING CHAIN GUIDE 1. Check: 8 timing chain guide (exhaust side) Damage/wear Replace EAS00267 INSTALLING THE PISTON AND CYLINDER 1. Install: 8 oil ring expander 1 8 oil ring rail 2 8 2nd ring 3 8 top ring 4 NOTE: Be sure to install the piston rings so that the...
  • Page 195 CYLINDER AND PISTON 3. Install: 8 gasket 8 dowel pins 2 4. Lubricate: 8 piston 8 piston rings 8 cylinder (with the recommended lubricant) Recommended lubricant Engine oil 5. Offset: 8 piston ring end gaps a Top ring b Lower oil ring rail c Upper oil ring rail d 2nd ring A Exhaust side...

  • Page 196: Crankcase Cover

    BELT DRIVE EAS00316 BELT DRIVE CRANKCASE COVER • • 10Nm(1.0m kg, 7.2 ft • • 7Nm(0.7m kg, 5.1 ft • • 23Nm(2.3m kg, 16.6 ft Order Job/Part Q’ty Remarks Removing the belt drive Remove the parts in the order listed. Kickstarter Crankcase cover - 3 V-belt case air filter element holder...

  • Page 197: Kickstarter

    BELT DRIVE EAS00338 KICKSTARTER • • 9Nm(0.9m kg, 6.5 ft Order Job/Part Q’ty Remarks Removing the kickstarter Remove the parts in the order listed. Crankcase cover Refer to “CRANKCASE COVER “. Plate (V-belt guide) Gasket Kick pinion gear Kick pinion gear clip Refer to “INSTALLING THE KICKSTARTER“.

  • Page 198: Installing The Kickstarter

    BELT DRIVE EAS00340 INSTALLING THE KICKSTARTER 1. Install: 8 solid bush 1 8 kickstarter shaft 2 8 kickstarter spring 3 2. Hook: 8 kickstarter spring NOTE: Hook the spring enda on the kickstarter shaft b as shown, and hook the other end c on the projectiond .

  • Page 199: V-Belt, Clutch, Primary And Secondary Sheave

    BELT DRIVE V-BELT, CLUTCH, PRIMARY AND SECONDARY SHEAVE • • 60Nm(6.0m kg, 43.4 ft • • 55Nm(5.5m kg, 39.8 ft Order Job/Part Q’ty Remarks Removing the V-belt, clutch, primary Remove the parts in the order listed. and secondary sheave Primary sheave nut / Plate washer Oneway clutch Refer to “...

  • Page 200: Disassembling The Secondary Sheave

    BELT DRIVE DISASSEMBLING THE SECONDARY SHEAVE • • 90Nm(9.0m kg, 65.1 ft Order Job/Part Q’ty Remarks Disassembling the secondary Disassemble the parts in the order listed. sheave Clutch carrier nut Clutch carrier Clutch shoe spring Compression spring Spring seat Refer to “ REMOVING AND INSTALLING Guide pin THE SECONDARY SHEAVE “...

  • Page 201: Removing The Primary Sheave

    BELT DRIVE EAS00317 REMOVING THE PRIMARY SHEAVE 1. Remove: 8 primary sheave nut 1 8 plate washer 8 primary fixed sheave 2 NOTE: While holding the primary fixed sheave with the rotor holding tool 3, loosen the primary fixed sheave nut. Rotor holding tool: 90890-01235 (YU-01235) EAS00318...

  • Page 202: Disassembling The Secondary Sheave

    BELT DRIVE 3. Remove: 8 secondary sheave assembly 1 8 V-belt 2 NOTE: Remove the V-belt and clutch assembly from the primary sheave side. EAS00319 DISASSEMBLING THE SECONDARY SHEAVE 1. Remove: 8 clutch carrier nut 1 NOTE: Install the clutch spring holder 2 and clutch spring holder arm 3 onto the secondary sheave as shown.

  • Page 203: Checking The V-Belt

    BELT DRIVE EAS00320 CHECKING THE V-BELT 1. Check: 8 V-belt 1 Cracks/damage/wear Replace. Grease/oil Clean the primary and sec- ondary sheave. 2. Measure: 8 V-belt width a Out of specification Replace. V-belt width 21.6 mm (0.0850 in) <Limit>: 19.5 mm (0.768 in) CHECKING THE PRIMARY SHEAVE 1.

  • Page 204: Checking The Slider

    BELT DRIVE CHECKING THE SLIDER Check: slider 1 Damage/wear Replace EAS00322 CHECKING THE SECONDARY SHEAVE 1. Check: 8secondary fixed sheave 8secondary sliding sheave Cracks/damage/wear Replace the sec- ondary fixed and sliding sheaves as a set. 2. Check: 8torque cam groove 1 Damage/wear Replace the secondary fixed and sliding sheaves as a set.
  • Page 205 BELT DRIVE 3. Install: 8 slider 1 8 primary sliding sheave 2 8 cam 3 5-44...

  • Page 206: Assembling The Secondary Sheave

    BELT DRIVE EAS00324 ASSEMBLING THE SECONDARY SHEAVE 1. Lubricate: 8 secondary fixed sheave’s inner surface 1 8 secondary sliding sheave’s inner surface 8 torque cam groove 8 oil seals 8 bearings (with the recommended lubricant) Recommended lubricant BEL-RAY assembly lube 2.

  • Page 207: Installing The Belt Drive

    BELT DRIVE 5. Install: 8 secondary sheave 1 8 spring 8 clutch carrier 2 NOTE: Attach the clutch spring holder 3 and clutch spring holder arm 4 onto the secondary sheave as shown. Then, compress the spring, and tighten the clutch carrier nut 5. Clutch spring holder 90890-01337 (YM-33285) ( YM-33285-6)
  • Page 208 BELT DRIVE 2. Install: 8 clutch carrier nut 1 90 Nm (9.0 m • kg, 65.1 ft • lb) NOTE: While holding the clutch carrier with the rotor holding tool 2, tighten the clutch carrier nut with the locknut wrench 3. Rotor holding tool 90890-01235 Locknut wrench...

  • Page 209: Starter Clutch And Starter Motor

    STARTER CLUTCH AND STARTER MOTOR STARTER CLUTCH AND STARTER MOTOR • • 7Nm(0.7m kg, 5.1 ft • • 7Nm(0.7m kg, 5.1 ft Order Job/Part Q’ty Remarks Removing the starter clutch and Disassemble the parts in the order listed. starter motor Primary sheave Refer to “...

  • Page 210: Checking The Starter Wheel Gear

    STARTER CLUTCH AND STARTER MOTOR CHECKING THE STARTER WHEEL GEAR 1. Check: 8 starter wheel gear 1 8 idle gear2 Burrs/chips/roughness/wear Replace 2. Check: 8 starter clutch operation ***************************************************** a. Install the starter clutch gear 1 onto the starter clutch2 and hold the starter clutch. b.

  • Page 211: C.d.i. Magneto

    C.D.I. MAGNETO C.D.I. MAGNETO • • 7Nm(0.7m kg, 5.1 ft • • 70Nm(7.0m kg, 50.6 ft Order Job/Part Q’ty Remarks Removing the C.D.I. magneto Disassemble the parts in the order listed. Air shroud 1 Refer to “CYLINDER HEAD”in chapter 3. C.D.I.

  • Page 212: Removing The C.d.i. Magneto

    C.D.I. MAGNETO REMOVING THE C.D.I. MAGNETO 1. Remove: 8 nut 1 8 plate washer NOTE: 8 While holding the C.D.I. magneto rotor with the holding tool 2, loosen the C.D.I. mag- neto nut1. 8 Do not allow the sheave holder to touch the projection on the C.D.I.

  • Page 213: Installing The C.d.i. Magneto

    C.D.I. MAGNETO INSTALLING THE C.D.I. MAGNETO 1. Install: 8 C.D.I. magneto rotor 1 NOTE: 8 Clean the tapered portion of the crankshaft and the magneto rotor hub. 8 When installing the magneto rotor, make sure the woodruff key is properly seated in the keyway of the crankshaft.

  • Page 214: Oil Pump

    OIL PUMP EAS00360 OIL PUMP • • 7Nm(0.7m kg, 5.1 ft • • 7Nm(0.7m kg, 5.1 ft Order Job/Part Q’ty Remarks Disassembling the oil pump Remove the parts in the order listed. C.D.I. magneto Refer to “ C.D.I. MAGNETO “ Cover O-ring Gasket...

  • Page 215: Checking The Oil Pump

    OIL PUMP EAS00364 CHECKING THE OIL PUMP 1. Check: 8 oil pump driven gear 1 Cracks/damage/wear Replace the de- fective part(s). 2. Measure: 8 inner-rotor-to-outer-rotor-tip clearance a 8 outer-rotor-to-oil-pump-housing clear- ance b 8 oil-pump-housing-to-inner-rotor-and- outer-rotor clearance c Out of specification Replace the oil pump.

  • Page 216: Installing The Oil Pump

    OIL PUMP 3. Check: 8 oil pump operation Rough movement Repeat steps (1) and (2) or replace the defective part(s). EAS00376 INSTALLING THE OIL PUMP 1. Install: 8 gasket 1 8 oil pump assembly2 8 oil pump bolt 7 Nm (0.7 m • kg, 5.1 ft • lb) After tightening the bolts, make sure the oil pump turns smoothly.

  • Page 217: Transmission

    TRANSMISSION EAS00419 TRANSMISSION • • 12Nm(1.2m kg, 8.7 ft Order Job/Part Q’ty Remarks Removing the transmission, shift Remove the parts in the order listed. drum assembly, and shift forks Transmission oil Drain. Rear wheel Refer to “REAR WHEEL AND REAR BRAKE “...

  • Page 218: Checking The Transmission

    TRANSMISSION EAS00425 CHECKING THE TRANSMISSION 1. Measure: 8 main axle runout (with a centering device and dial gauge ) Out of specification Replace the main axle. Main axle runout limit 0.02 mm (0.0008 in) 2. Measure: 8 primary drive gear shaft runout (with a centering device and dial gauge ) Out of specification Replace the drive...

  • Page 219: Crankcase And Crankshaft

    CRANKCASE AND CRANKSHAFT EAS00381 CRANKCASE AND CRANKSHAFT • • 12Nm(1.2m kg, 8.7 ft • • 8Nm(0.8m kg, 5.8 ft • • 32Nm(3.2m kg, 23.1 ft • • 32Nm(3.2m kg, 23.1 ft Order Job/Part Q’ty Remarks Removing the crankshaft assembly Remove the parts in the order listed. Engine Refer to “...
  • Page 220 CRANKCASE AND CRANKSHAFT • • 12Nm(1.2m kg, 8.7 ft • • 8Nm(0.8m kg, 5.8 ft • • 32Nm(3.2m kg, 23.1 ft • • 32Nm(3.2m kg, 23.1 ft Order Job/Part Q’ty Remarks Dowel pin Crankshaft Refer to “DISASSEMBLING THE CRANKCASE “ Timing chain Crankcase ( left ) Refer to “INSTALLING THE CRANK-...

  • Page 221: Disassembling The Crankcase

    CRANKCASE AND CRANKSHAFT DISASSEMBLING THE CRANKCASE 1. Remove: 8 centerstand assembly 2. Remove: 8 crankcase bolts 1 NOTE: Loosen each bolt 1/4 of a turn at a time, in stages and in a crisscross pattern. After all of the bolts are fully loosened, remove them.

  • Page 222: Removing The Crankshaft Assembly

    CRANKCASE AND CRANKSHAFT EAS00389 REMOVING THE CRANKSHAFT ASSEMBLY 1. Remove: 8 crankshaft assembly 1 8 timing chain 2 NOTE: 8 Before removing the crankshaft assembly, remove the timing chain from the crankshaft sprocket. 8 The crankshaft assembly cannot be re- moved if the timing chain is attached onto the crankshaft sprocket.

  • Page 223: Checking The Crankshaft And Connecting Rod

    CRANKCASE AND CRANKSHAFT EAS00394 CHECKING THE CRANKSHAFT AND CON- NECTING ROD 1. Measure: 8 crankshaft runout Out of specification Replace the crank- shaft, bearing or both. NOTE: Turn the crankshaft slowly. Maximum crankshaft runout 0.03 mm (0.0012 in) 2. Measure: 8 big end side clearance Out of specification Replace the big end...

  • Page 224: Installing The Crankshaft

    CRANKCASE AND CRANKSHAFT 5. Check: 8 crankshaft journal Scratches/wear Replace the crank- shaft. 8 crankshaft journal oil passage Obstruction Blow out with compressed air. EAS00408 INSTALLING THE CRANKSHAFT 1. Install: 8 crankshaft assembly 1 8 crankcase2 8 timing chain3 To avoid scratching the crankshaft and to ease the installation procedure, lubricate the oil seal lips with lithium-soap-based grease and each bearing with engine oil.

  • Page 225: Assembling The Crankcase

    1. Thoroughly clean all the gasket mating sur- faces and crankcase mating surfaces. 2. Apply: 8 sealant (onto the crankcase mating surfaces) Yamaha bond No. 1215 90890-85505 (ACC-11001-05-01) NOTE: Do not allow any sealant to come into contact with the oil gallery.

  • Page 226: Carb

    CARB CHAPTER 6 CARBRETOR CARBURETOR ..................6-1 CHECKING THE CARBURETOR ............. 6-3 ASSEMBLING THE CARBURETOR..........6-5 INSTALLING THE CARBURETOR ........... 6-6 MEASURING AND ADJUSTING THE FUEL LEVEL ....... 6-7 CHECKING THE FUEL COCK ............6-8 CHECKING THE AUTOCHOKE UNIT ..........6-8 AIR INDUCTION SYSTEM ..............
  • Page 227 CARB CARBURETOR CARBURETOR EAS00483 CARBURETOR Order Job/Part Q’ty Remarks Disassembling the carburetor Remove the parts in the order listed. Auto choke unit Auto choke holder Throttle stop screw / Spring Bracket Clamp Vacuum chamber cover / Piston valve spring Piston valve Jet needle kit Float chamber Gasket...
  • Page 228 CARB CARBURETOR Order Job/Part Q’ty Remarks Carburetor heater Ground terminal For assembly, reverse the disassembly procedure.

  • Page 229: Carburetor

    CARB CARBURETOR EAS00485 CHECKING THE CARBURETOR 1. Check: 8 carburetor body 8 float chamber Cracks/damage Replace. 2. Check: 8 fuel passages Obstruction Clean. ***************************************************** a. Wash the carburetor in a petroleum-based solvent. Do not use any caustic carburetor cleaning solution. b.
  • Page 230 CARB CARBURETOR 6. Check: 8 needle valve 1 8 needle valve seat 2 Damage/obstruction/wear Replace the needle valve, needle valve seat and O- ring as a set. 7. Check: 8 O-ring 3 Damage/wear Replace the needle valve, needle valve seat and O-ring as a set.

  • Page 231: Assembling The Carburetor

    CARB CARBURETOR EAS00487 ASSEMBLING THE CARBURETOR 8 8 8 8 8 Before assembling the carburetor, wash all of the parts in a petroleum-based sol- vent. 8 8 8 8 8 Always use a new gasket. 1. Install: 8 main nozzle 1 8 main jet 2 8 pilot jet 3 2.

  • Page 232: Installing The Carburetor

    CARB CARBURETOR EAS00492 INSTALLING THE CARBURETOR 1. Adjust: 8 engine idling speed Engine idling speed 1,600 ~ 1,700r/min Refer to “ADJUSTING THE ENGINE IDLING SPEED” in chapter 3. 2. Adjust: 8 throttle cable free play Throttle cable free play (at the flange of the throttle grip) 3 ~ 5 mm (0.12 ~ 0.20 in) Refer to “ADJUSTING THE THROTTLE...

  • Page 233: Measuring And Adjusting The Fuel Level

    CARB CARBURETOR EAS00498 MEASURING AND ADJUSTING THE FUEL LEVEL 1. Measure: 8 fuel level a Out of specification Adjust. Fuel level (below the float chamber mating surface) 6.5 ~ 7.5 mm (0.26 ~ 0.30 in) ***************************************************** a. Stand the motorcycle on a level surface. b.

  • Page 234: Checking The Fuel Cock

    CARB CARBURETOR EAS00505 CHECKING THE FUEL COCK 1. Check: 8fuel cock Cracks/damage/wear Replace. 2. Check: 8fuel cock strainer 1 obstruction clean. Blow out the jets with compressed air. Damage Replace. EAS00503 CHECKING THE AUTOCHOKE UNIT NOTE: When checking the autochoke unit, the ambient temperature must be lower than 45°C (113°F).
  • Page 235 CARB CARBURETOR 3. Check: 8 autochoke unit ***************************************************** a. Connect the autochoke unit leads to a 12.0- V battery for five minutes. Positive battery lead 1 black Negative battery lead 2 black b. Connect a 3.3-mm hose 3 to the starter air passage 4 and blow into the hose.

  • Page 236: Air Induction System

    CARB AIR INDUCTION SYSTEM AIR INDUCTION SYSTEM • • 4Nm(0.4m kg, 2.9 ft • • 31Nm(3.1m kg, 22.4 ft Order Job/Part Q’ty Remarks Removing the air induction system Remove the parts in the order listed. Hose (from AI air filter) Vacuum hose( from mainfold ) Hose (to cylinder head) Muffler assembly...

  • Page 237: Checking The Air Induction System

    CARB AIR INDUCTION SYSTEM EAS00510 CHECKING THE AIR INDUCTION SYSTEM 1. Check: 8 hoses Loose connection Connect properly. Cracks/damage Replace. 8 pipe Cracks/damage Replace. 2. Check: 8 air cut-off valve Cracks/damage Replace. NOTE: When the negative pressure is applied to the part 1, check that the continuity in the direction of arrow mark is completely lost.

  • Page 238: Elec

    ELEC CHAPTER 7 ELECTRICAL ELECTRICAL COMPONENTS ..............7-1 WIRING DIAGRAM ................... 7-2 CHECKING SWITCH CONTINUITY ............7-4 CHECKING THE SWITCHES ..............7-5 CHECKING THE BULBS AND BULB SOCKETS ........7-6 TYPES OF BULBS ................7-6 CHECKING THE CONDITION OF THE BULBS ....... 7-7 CHECKING THE CONDITION OF THE BULB SOCKETS ....

  • Page 239: Electrical Components

    ELEC ELECTRICAL COMPONENTS EAS00729 ELECTRICAL ELECTRICAL COMPONENTS 1 Wire harness q Thermo switch 2 Battery w Fuel sender 3 C.D.I. unit e Starter relay 4 Carburetor heater r Turn signal relay 5 Sidestand switch t Front brake light switch 6 Horn y Starting circuit cut-off relay 7 Rectifier/Regulator 8 Ignition coil...

  • Page 240: Wiring Diagram

    ELEC WIRING DIAGRAM WIRING DIAGRAM...
  • Page 241 ELEC WIRING DIAGRAM 1 Main switch Color Cod 2 C.D.I. magneto Black 3 Rectifier/Regulator Brown 4 Battery Chocolate 5 Main fuse Dark green 6 Battery (+) lead Green 7 Battery (-) lead Blue 8 Wire lead Orange 9 Starter relay Pink 0 Starter motor q C.D.I.

  • Page 242: Checking Switch Continuity

    ELEC CHECKING SWITCH CONTINUITY EAS00730 CHECKING SWITCH CONTINUITY Check each switch for continuity with the pocket tester. If the continuity reading is incorrect, check the wiring connections and if necessary, replace the switch. Never insert the tester probes into the coupler terminal slots.

  • Page 243: Checking The Switches

    ELEC CHECKING THE SWITCHES EAS00731 CHECKING THE SWITCHES Check each switch for damage or wear, proper connections, and also for continuity between the terminals. Refer to “CHECKING SWITCH CONTINUITY”. Damage/wear Repair or replace. Improperly connected Properly connect. Incorrect continuity reading Replace the switch.

  • Page 244: Checking The Bulbs And Bulb Sockets

    ELEC CHECKING THE BULBS AND BULB SOCKETS EAS00733 CHECKING THE BULBS AND BULB SOCKETS Check each bulb and bulb socket for damage or wear, proper connections, and also for continu- ity between the terminals. Damage/wear Repair or replace the bulb, bulb socket or both. Improperly connected Properly con- nect.
  • Page 245 ELEC CHECKING THE BULBS AND BULB SOCKETS CHECKING THE CONDITION OF THE BULBS The following procedure applies to all of the bulbs. 1. Remove: 8 bulb Since the headlight bulb gets extremely hot, keep flammable products and your hands away from the bulb until it has cooled down. 8 8 8 8 8 Be sure to hold the socket firmly when removing the bulb.

  • Page 246: Checking The Condition Of The Bulbs

    ELEC CHECKING THE BULBS AND BULB SOCKETS CHECKING THE CONDITION OF THE BULB SOCKETS The following procedure applies to all of the bulb sockets. Check: 8 bulb socket (for continuity) (with the pocket tester) No continuity Replace. Pocket tester 90890-03132 (YU-03112-C) NOTE: Check each bulb socket for continuity in the same manner as described in the bulb section;...

  • Page 247: Ignition System

    ELEC IGNITION SYSTEM IGNITION SYSTEM CIRCUIT DIAGRAM 1 Main switch 2 Pickup coil 4 Battery 5 Main fuse 6 Battery (+) lead 7 Battery (-) lead 8 Wire lead q C.D.I. unit w Ignition coil u Engine stop switch o Sidestand switch...

  • Page 248: Troubleshooting

    ELEC IGNITION SYSTEM EAS00736 EAS00738 TROUBLESHOOTING Main Fuse 8 Check the fuse for continuity. The ignition system fails to operate (no Refer to “CHECKING THE FUSE” in chap- spark or intermittent spark). ter 3. 8 Is the fuse OK? Check: 1.
  • Page 249 ELEC IGNITION SYSTEM EAS00742 EAS00744 4. Ignition spark gap 5. Spark plug cap resistance 8 Disconnect the spark plug cap from the 8Remove the spark plug cap from the spark plug. spark plug lead. 8Connect the pocket tester (“Ω × 1k” 8 Connect the ignition checker 1 as shown.
  • Page 250 ELEC IGNITION SYSTEM EAS00749 7. Main switch 8 Check the main switch for continuity. Refer to “CHECKING THE SWITCHES”. 8 Is the main switch OK? Replace the main switch. 8 Measure the primary coil resistance. EAS00750 8. Engine stop switch Primary coil resistance 8 Check the engine stopswitch for continu- 0.184 ~ 0.276 Ω...
  • Page 251 ELEC IGNITION SYSTEM EAS00748 10.Pickup coil resistance 8Disconnect the pickup coil coupler from the wire harness. 8Connect the pocket tester (Ω × 100) to the pickup coil terminal as shown. white/red 1 1 1 1 1 Positive tester probe white/blue 2 2 2 2 2 Negative tester probe 8Measure the pickup coil resistance.

  • Page 252: Electric Starting System

    ELEC ELECTRIC STARTING SYSTEM ELECTRIC STARTING SYSTEM CIRCUIT DIAGRAM 1 Main switch 4 Battery 5 Main fuse 6 Battery (+) lead 7 Battery (-) lead 8 Wire lead 9 Starter relay 0 Starter motor q C.D.I. unit r Front brake light switch t Rear brake light switch y Start switch u Engine stop switch...

  • Page 253: Starting Circuit Cut-Off System Operation

    ELEC ELECTRIC STARTING SYSTEM EAS00756 STARTING CIRCUIT CUT-OFF SYSTEM OP- ERATION If the main switch is set to “ON” (switchis closed), the starter motor can only operate if at least one of the following conditions is met: 8 The sidesatnd switch is up (the side stand switch is closed), and the brake lever ( front or rear) is pulled to the handlebar (the brake light switch is closed)

  • Page 254: Troubleshooting

    ELEC ELECTRIC STARTING SYSTEM EAS00757 EAS00738 TROUBLESHOOTING 1. Main fuse 8 Check the fuse for continuity. The starter motor fails to turn. Refer to “CHECKING THE FUSE” in chapter 3. 8 Is the fuse OK? Check: 1. Main fuse 2. Battery 3.
  • Page 255 ELEC ELECTRIC STARTING SYSTEM EAS00758 EAS00759 3. Starter motor 4. Starting circuit cut-off relay 8 Connect the positive battery terminal 1 8Disconnect the starting circuit cut-off re- and starter motor lead 2 with a jumper lay coupler from the wire harness. 8Connect the pocket tester (Ω...
  • Page 256 ELEC ELECTRIC STARTING SYSTEM EAS00761 EAS00751 5. Starter relay 7. Brake light switch(front and rear) 8 Disconnect the starter relay coupler from 8 Check the brake light switch for continu- the coupler. ity. 8 Connect the pocket tester (Ω × 1) and Refer to “CHECKING THE SWITCHES”.
  • Page 257 ELEC ELECTRIC STARTING SYSTEM EAS00766 11. Wiring 8 Check the entire starting system’s wir- ing. Refer to “CIRCUIT DIAGRAM”. 8 Is the starting system’s wiring properly connected and without defects? Properly connect or The starting sys- repair the starting tem circuit is OK. system’s wiring or replace the C.D.I.
  • Page 258 ELEC ELECTRIC STARTING SYSTEM STARTER MOTOR • • 3.5Nm(0.35m kg, 2.5 ft Order Job/Part Q’ty Remarks Starter motor removal Remove the parts in the order listed. Air filter case Refer to“LEADS, HOSES AND REAR BRAKE ”in chapter 5. Starter motor lead Starter motor For installation, reverse the removal pro- cedure.

  • Page 259: Checking The Starter Motor

    ELEC ELECTRIC STARTING SYSTEM EAS00769 CHECKING THE STARTER MOTOR 1. Check: 8 commutator Dirt Clean with 600-grit sandpaper. 2. Measure: 8 commutator diameter a Out of specification Replace the starter motor. Commutator wear limit 21 mm (0.83 in) Measure: 8 mica undercut a Out of specification Scrape the mica to the proper measurement with a hack-...
  • Page 260 ELEC ELECTRIC STARTING SYSTEM 5. Measure: 8 brush length a Out of specification Replace the brushes as a set. Brush length wear limit 3.5 mm (0.14 in) 6. Measure: 8 brush spring force Out of specification Replace the brush springs as a set. Brush spring force 5.52 ~ 8.28 N 7.

  • Page 261: Assembling The Starter Motor

    ELEC ELECTRIC STARTING SYSTEM EAS00772 ASSEMBLING THE STARTER MOTOR 1. Install: 8 brush spring 1 8 brush 2 8 armature coil 2. Install: 8 gasket 1 8 starter motor front bracket 2 8 starter motor rear bracket 3 NOTE: Align the match marks a on the starter motor yoke with the match marks b on the front and starter motor rear brackets.

  • Page 262: Charging System

    ELEC CHARGING SYSTEM EAS00773 CHARGING SYSTEM CIRCUIT DIAGRAM 2 C.D.I. magneto 3 Rectifier/Regulator 4 Battery 5 Main fuse 6 Battery (+) lead 7 Battery (-) lead 7-24...

  • Page 263: Troubleshooting

    ELEC CHARGING SYSTEM EAS00774 EAS00739 TROUBLESHOOTING 2. Battery 8Check the condition of the battery. The battery is not being charged. Refer to “CHECKING AND CHARGING THE BATTERY” in chapter 3. Check: 1. main fuse Minimum open-circuit voltage 2. battery 12.8 V or more at 20°C 3.
  • Page 264 ELEC CHARGING SYSTEM EAS00754 NOTE: 5. Wiring Make sure the battery is fully charged. 8Check the entire charging system’s wir- ing. 8Is the charging voltage within specifica- Refer to “CIRCUIT DIAGRAM”. tion? 8Is the charging system’s wiring properly connected and without defects? The charging circuit is OK.

  • Page 265: Lighting System

    ELEC LIGHTING SYSTEM EAS00780 LIGHTING SYSTEM CIRCUIT DIAGRAM 2 C.D.I. magneto f Speedometer light h Dimmer switch j High beam indicator light l Fuel lever meter light z Headlight 7-27...

  • Page 266: Troubleshooting

    ELEC LIGHTING SYSTEM EAS00781 EAS00739 TROUBLESHOOTING 2. Battery 8Check the condition of the battery. Any of the following fail to light: headlight, Refer to “CHECKING AND CHARGING high beam indicator light, fuel level meter THE BATTERY” in chapter 3. light or meter light. Minimum open-circuit voltage Check: 12.8 V or more at 20°C...

  • Page 267: Checking The Lighting System

    ELEC LIGHTING SYSTEM EAS00787 EAS00788 5. Wiring CHECKING THE LIGHTING SYSTEM 8 Check the entire lighting system’s wir- 1. The headlight and the high beam indicator ing. light fail to come on. Refer to “CIRCUIT DIAGRAM”. 8 Is the lighting system’s wiring properly 1.
  • Page 268 ELEC LIGHTING SYSTEM 3. Voltage 8 Connect the pocket tester (DC 20 V) to the headlight and high beam indicator The wiring circuit from the This circuit is OK. light couplers as shown. main switch to the head- When the dimmer switch is set to “%” light coupler and hight When the dimmer switch is set to “&”...
  • Page 269 ELEC LIGHTING SYSTEM EAS00789 EAS00841 2. The meter light fails to come on. 3. Fuel level meter light 8 Check the fuel level meter light bulb and 1. Meter light bulb and socket 8 Check the meter light bulb and socket socket for continuity.
  • Page 270 ELEC LIGHTING SYSTEM EAS00748 4. Lighting coil resistance 8 Disconnect the lighting coil coupler from the wire harness. 8 Connect the pocket tester (Ω × 1) to the lighting coil terminal as shown. yellow/red 1 1 1 1 1 Positive tester probe Negative tester probe ground 8 Measure the lighting coil resistance.

  • Page 271: Signaling System

    ELEC SIGNALING SYSTEM EAS00793 SIGNALING SYSTEM CIRCUIT DIAGRAM 1 Main switch 4 Battery 5 Main fuse 6 Battery (+) lead 7 Battery (-) lead 8 Wire lead r Front brake light switch t Rear brake light switch p Horn a Horn switch s Turn signal switch d Turn signal relay g Tail/brake light...

  • Page 272: Troubleshooting

    ELEC SIGNALING SYSTEM EAS00794 EAS00739 TROUBLESHOOTING 2. Battery 8Check the condition of the battery. 8 8 8 8 8 Any of the following fail to light: turn Refer to “CHECKING AND CHARGING signal light, brake light or an indica- THE BATTERY” in chapter 3. tor light.

  • Page 273: Checking The Signaling System

    ELEC SIGNALING SYSTEM EAS00796 3. Horn CHECKING THE SIGNALING SYSTEM 8Disconnect the pink connector at the horn terminal. The horn fails to sound. 8Connect a jumper lead 1 to the horn terminal and ground the jumper lead. 1. Horn switch 8Set the main switch to “ON”.
  • Page 274 ELEC SIGNALING SYSTEM EAS00798 3. Voltage The tail/brake light fails to come on. 8 Connect the pocket tester (DC 20 V) to the tail/brake light coupler (wire harness 1. Tail/brake light bulb and socket side) as shown. 8 Check the tail/brake light bulb and socket green/ yellow 1 1 1 1 1 Positive tester probe for continuity.
  • Page 275 ELEC SIGNALING SYSTEM EAS00799 3. Voltage 3. The turn signal light, turn signal indicator 8Connect the pocket tester (DC 20 V) to light or both fail to blink. the turn signal relay coupler (wire har- ness side) as shown. 1. Turn signal light and turn signal indicator brown 1 1 1 1 1 Positive tester probe light bulbs and sockets...
  • Page 276 ELEC SIGNALING SYSTEM 4. Voltage 5. Voltage 8Connect the pocket tester (DC 20 V) to 8Connect the pocket tester (DC 20 V) to the turn signal relay coupler (wire har- the turn signal light connector or meter ness side) as shown. assembly coupler (wire harness side) as brown/white 1 1 1 1 1 Positive tester probe...
  • Page 277 ELEC SIGNALING SYSTEM EAS00804 2. Voltage 4. The fuel level meter fails to operate. 8 Connect the pocket tester (DC 20 V) to the meter light coupler (wire harness 1. Fuel sender side) as shown. 8 Remove the fuel sender from the fuel brown 1 1 1 1 1 Positive tester probe tank.
  • Page 278 ELEC SIGNALING SYSTEM 3. Fuel level meter 8 Set the main switch to “ON”. 8 Move the float up 1 or down 2. 8 Check that the fuel level meter needle moves to “F” or “E”. NOTE: Before reading the fuel level meter, leave the float in one position (either up or down) for at least three minutes.

  • Page 279: Craburetor Heating System

    ELEC CRABURETOR HEATING SYSTEM EAS00820 CARBURETOR HEATING SYSTEM CIRCUIT DIAGRAM 1 Main switch 4 Battery 5 Main fuse 6 Battery (+) lead 7 Battery (-) lead 8 Wire lead n Thermo switch m Carburetor heater 7-41...

  • Page 280: Troubleshooting

    ELEC CRABURETOR HEATING SYSTEM EAS00821 EAS00739 TROUBLESHOOTING 2. Battery 8Check the condition of the battery. The carburetor heating system fails to Refer to “CHECKING AND CHARGING operate. THE BATTERY” in chapter 3. Check: Minimum open-circuit voltage 1. Main fuse 12.8 V or more at 20°C 2.
  • Page 281 ELEC CRABURETOR HEATING SYSTEM EAS00823 A The coolant temperature sensor circuit is 4. Thermo switch closed. 8 Remove the thermo switch from the B The coolant temperature sensor circuit is thermo switch plate wire harness. open. 8 Connect the pocket tester to the (Ω × 1) to the thermo switch 1 as shown.
  • Page 282 ELEC CRABURETOR HEATING SYSTEM EAS00826 6. Wiring 8 Check the entire carburetor heating system’s wiring. Refer to “CIRCUIT DIAGRAM”. 8 Is the carburetor heating system’s wir- ing properly connected and without de- fects? Properly connect or re- pair the carburetor heat- ing system’s wiring.

  • Page 283: Auto Choke System

    ELEC AUTO CHOKE SYSTEM AUTO CHOKE SYSTEM CIRCUIT DIAGRAM 2 C.D.I. magneto e Auto choke unit 7-45...

  • Page 284: Troubleshooting

    ELEC AUTO CHOKE SYSTEM EAS00748 TROUBLESHOOTING 1. Lighting coil resistance 8 Disconnect the lighting coil coupler from The auto choke system fails to operate. the wire harness. 8 Connect the pocket tester (Ω × 1) to the Check: lighting coil terminal as shown. 1.
  • Page 285 ELEC AUTO CHOKE SYSTEM 2. Auto choke unit resistance 8Disconnect the auto choke unit coupler from wire harness. 8Connect the Pocket tester(Ω × 1) to the Auto choke unit coupler as shown. black 1 1 1 1 1 Positive tester probe black 2 2 2 2 2 Negative tester probe 8Measure the auto choke unit resistance.

  • Page 286: Trbl Shtg

    TRBL SHTG CHAPTER 8 TROUBLE SHOOTING STARTING FAILURES ................8-1 ENGINE ....................8-1 FUEL SYSTEM .................. 8-1 ELECTRICAL SYSTEMS ..............8-1 STARTING FAILURES/INCORRECT ENGINE IDLING SPEED .... 8-2 INCORRECT ENGINE IDLING SPEED ........... 8-2 ENGINE ....................8-2 FUEL SYSTEM .................. 8-2 ELECTRICAL SYSTEMS ..............
  • Page 287 TRBL SHTG UNSTABLE HANDLING/FAULTY LIGHTING OR SIGNALING SYSTEM ....................8-5 UNSTABLE HANDLING ................8-5 FAULTY LIGHTING OR SIGNALING SYSTEM ........8-5 HEADLIGHT DOES NOT COME ON ..........8-5 HEADLIGHT BULB BURNT OUT ............. 8-5 TAIL/BRAKE LIGHT DOES NOT COME ON ........8-5 TAIL/BRAKE LIGHT BULB BURNT OUT .........

  • Page 288: Starting Failures

    TRBL STARTING FAILURES SHTG EAS00844 TROUBLESHOOTING NOTE: The following guide for troubleshooting does not cover all the possible causes of trouble. It should be helpful, however, as a guide to basic troubleshooting. Refer to the relative procedure in this manual for checks, adjustments, and replacement of parts.

  • Page 289: Starting Failures/Incorrect Engine Idling Speed

    STARTING FAILURES/ TRBL INCORRECT ENGINE IDLING SPEED SHTG EAS00846 Ignition system INCORRECT ENGINE IDLING 8Faulty C.D.I unit 8Faulty pickup coil SPEED 8Broken magneto rotor woodruff key ENGINE Switches and wiring Cylinder and cylinder head 8Faulty main switch 8Incorrect valve clearance 8Faulty engine stop switch 8Damaged valve train components 8Broken or shorted wiring...

  • Page 290: Poor Medium-And-High-Speed Performance/Faulty Clutch

    POOR MEDIUM-AND-HIGH-SPEED PERFORMANCE/ TRBL FAULTY CLUTCH SHTG EAS00853 EAS00849 POOR MEDIUM-AND-HIGH-SPEED FAULTY CLUTCH PERFORMANCE ENGINE OPERATES BUT SCOOTER WILL NOT MOVE Refer to “STARTING FAILURES”. V-belt ENGINE 8Bent, damaged or worn V-belt Air filter 8Slipping V-belt 8Clogged air filter element Primary pulley cam and primary pulley slider Air intake system 8Damaged or worn primary pulley cam...

  • Page 291: Fork Legs

    TRBL OVERHEATING/POOR BRAKING PERFORMANCE/ SHTG FAULTY FRONT FORK LEGS EAS00859 POOR SPEED PERFORMANCE POOR BRAKING PERFORMANCE V-belt 8Oil or grease on the V-belt Disc brake 8Worn brake pad Primary pulley weight(s) 8Worn brake disc 8Faulty operation 8Air in hydraulic brake system 8Worn primary pulley weight 8Leaking brake fluid 8Faulty brake caliper kit...
  • Page 292 UNSTABLE HANDLING/ TRBL FAULTY LIGHTING OR SIGNALING SYSTEM SHTG EAS00862 EAS00866 UNSTABLE HANDLING FAULTY LIGHTING OR SIGNALING SYSTEM Handlebar 8Bent or improperly installed handlebar HEADLIGHT DOES NOT COME ON 8Wrong headlight bulb Steering head components 8Too many electrical accessories 8Improperly installed upper bracket 8Hard charging 8Improperly installed lower bracket 8Incorrect connection...
  • Page 293 TRBL FAULTY LIGHTING OR SIGNALING SYSTEM SHTG TURN SIGNAL REMAINS LIT 8Faulty turn signal relay 8Burnt-out turn signal bulb TURN SIGNAL BLINKS QUICKLY 8Incorrect turn signal bulb 8Faulty turn signal relay 8Burnt-out turn signal bulb HORN DOES NOT SOUND 8Improperly adjusted horn 8Damaged or faulty horn 8Faulty main switch 8Faulty horn switch...
  • Page 294 YAMAHA MOTOR TAIWAN CO., LTD...

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