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Yamaha TTR250L Service Manual

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TTR250L
C
(
)
SERVICE MANUAL
LIT-11616-12-57
5GF-28197-E0

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Summary of Contents for Yamaha TTR250L

  • Page 1 TTR250L SERVICE MANUAL LIT-11616-12-57 5GF-28197-E0...
  • Page 2 TTR250L(C) SERVICE MANUAL ©1999 by Yamaha Motor Corporation, U.S.A. 1st edition, January 1999 All rights reserved. Any reproduction or unauthorized use without the written permission of Yamaha Motor Corporation, U.S.A. is expressly prohibited. Printed in U.S.A. LIT-11616-12-57...
  • Page 3 EB001000 NOTICE This manual was produced by the Yamaha Motor Company 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, so it is assumed that anyone who uses this book to perform mainte- nance and repairs on Yamaha motorcycles has a basic understanding of the mechanical ideas and the procedures of motorcycle repair.
  • Page 4 EB002000 HOW TO USE THIS MANUAL MANUAL ORGANIZATION This manual is intended as a handy, easy-to-read reference book for the mechanic. It is divided into chapters, sections and sub-sections. Comprehensive explanations of all installa- tion, removal, disassembly, assembly, repair and inspection procedures are laid out with the individual steps in sequential order.
  • Page 5 EB003000 ILLUSTRATED SYMBOLS Illustrated symbols 1 to 8 are printed on the top right of each page and indicate the SPEC INFO subject of each chapter. 1 General information 2 Specifications INSP 3 Periodic inspections and adjustments 4 Engine overhall 5 Carburetor 6 Chassis 7 Electrical...
  • Page 6 TABLE OF CONTENTS GENERAL INFORMATION INFO SPECIFICATIONS SPEC PERIODIC CHECKS AND ADJUSTMENTS ENGINE CARBURETOR CARB CHASSIS CHAS – ELECTRICAL SYSTEM ELEC TROUBLESHOOTING TRBL SHTG...

  • Page 7: Table Of Contents

    CONTENTS CHAPTER 1. GENERAL INFORMATION MOTORCYCLE IDENTIFICATION ..............1-1 VEHICLE IDENTIFICATION NUMBER ..........1-1 ENGINE SERIAL NUMBER ..............1-1 IMPORTANT INFORMATION ..............1-2 PREPARATION FOR REMOVAL AND DISASSEMBLY ...... 1-2 ALL REPLACEMENT PARTS ..............1-3 GASKETS, OIL SEALS, AND O-RINGS ..........1-3 LOCK WASHERS/PLATES AND COTTER PINS ........
  • Page 8 CHAPTER 3. PERIODIC CHECKS AND ADJUSTMENTS PERIODIC INSPECTION AND ADJUSTMENT INTRODUCTION ................... 3-1 INFO PERIODIC MAINTENANCE/LUBRICATION ..........3-1 SEAT, FUEL TANK AND COVERS .............. 3-3 SPEC REMOVAL ..................... 3-3 INSTALLATION ..................3-4 ENGINE ......................3-6 INSP VALVE CLEARANCE ADJUSTMENT ..........3-6 TIMING CHAIN ADJUSTMENT ............
  • Page 9 FRONT FORK ADJUSTMENT ............3-39 REAR SHOCK ABSORBER ADJUSTMENT ........3-41 TIRE INSPECTION ................3-43 WHEEL INSPECTION ................. 3-46 SPOKES INSPECTION AND TIGHTENING ........3-46 CABLE INSPECTION AND LUBRICATION ........3-46 LEVER AND PEDAL LUBRICATION ..........3-47 SIDESTAND LUBRICATION .............. 3-47 ELECTRICAL ....................
  • Page 10 INSPECTION AND REPAIR ................ 4-16 CYLINDER HEAD ................4-16 VALVE SEAT ..................4-16 VALVE AND VALVE GUIDE ............... 4-20 VALVE SPRING .................. 4-21 CAMSHAFT ..................4-22 VALVE LIFTER ..................4-24 INFO TIMING CHAIN, SPROCKET AND CHAIN GUIDE ......4-24 CYLINDER AND PISTON ..............4-25 PISTON RING ..................
  • Page 11 CHAPTER 5. CARBURETOR CARBURETOR ....................5-1 REMOVAL ..................... 5-2 DISASSEMBLY ..................5-3 INSPECTION ..................5-5 ASSEMBLY ................... 5-7 INSTALLATION ..................5-9 FUEL LEVEL ADJUSTMENT .............. 5-10 THROTTLE VALVE POSITION ............5-11 CHAPTER 6. CHASSIS FRONT WHEEL ..................... 6-1 REMOVAL ..................... 6-2 INSPECTION ..................
  • Page 12 DRIVE CHAIN AND SPROCKETS .............. 6-72 REMOVAL ................... 6-73 INSPECTION ..................6-74 INSP INSTALLATION .................. 6-75 CHAPTER 7. ELECTRICAL TTR250L(C) CIRCUIT DIAGRAM ..............7-1 ELECTRICAL COMPONENTS ..............7-3 CARB CHECKING OF CONNECTIONS ..............7-5 IGNITION SYSTEM ..................7-6 CHAS ELECTRICAL STARTING SYSTEM ............7-12 –...
  • Page 13 FRONT FORK OIL LEAKAGE AND FRONT FORK MALFUNCTION ..8-4 OIL LEAKAGE ..................8-4 MALFUNCTION ..................8-4 INSTABLE HANDLING ................. 8-5 INSTABLE HANDLING ................. 8-5 FAULTY SIGNAL AND LIGHTING SYSTEM ..........8-6 HEADLIGHT DARK ................8-6 BULB BURNT OUT ................8-6 TTR250L(C) WIRING DIAGRAM...

  • Page 14: Chapter 1. General Information

    MOTORCYCLE IDENTIFICATION INFO GENERAL INFORMATION MOTORCYCLE IDENTIFICATION VEHICLE IDENTIFICATION NUMBER The vehicle identification number 1 is stamped into the right side of the steering head. NOTE: The vehicle identification number is used to identify your motorcycle and may be used to register your motorcycle with the licens- ing authority in your state.

  • Page 15: Important Information

    IMPORTANT INFORMATION INFO IMPORTANT INFORMATION PREPARATION FOR REMOVAL AND DISASSEMBLY 1.Remove all dirt, mud, dust, and foreign material before removing and disassem- bling. 2.Use proper tools and cleaning equipment. Refer to “SPECIAL TOOLS”. 3.When disassembling the motorcycle keep mated parts together. This includes gears, cylinder, piston and other mated parts that have been “mated”...

  • Page 16: All Replacement Parts

    IMPORTANT INFORMATION INFO ALL REPLACEMENT PARTS 1.Use only genuine Yamaha parts for all replacements. Use oil and/or grease rec- ommended by Yamaha for assembly and adjustment. Other brands may be similar in function and appearance, but inferior in quality. GASKETS, OIL SEALS, AND O-RINGS 1.All gaskets, seals and O-rings should be...

  • Page 17: Special Tools

    SPECIAL TOOLS INFO CIRCLIPS 1.All circlips should be inspected carefully before reassembly. Always replace piston pin clips after one use. Replace distorted circlips. When installing a circlip 1, make sure that the sharp-edged corner 2 is positioned opposite to the thrust 3 it receives.

  • Page 18: For Engine Service

    SPECIAL TOOLS INFO Piston pin puller P/N. YU-01304 FOR ENGINE SERVICE This tool is used to remove the piston pin. Sheave holder Rotor puller P/N. YS-01880 P/N. 2K7-85555-00 This tool is used to hold the rotor when removing or installing the rotor securing nut. This tool is used to remove the rotor.

  • Page 19: For Chassis Service

    SPECIAL TOOLS INFO Valve guide installer 5 mm (0.20 in) Crankshaft installing set P/N. YM-04098 P/N. YU-90050 This tool is needed to install the valve guides properly. These tools are used to install the crankshaft. Adapter (M10) Crank pot spacer P/N.

  • Page 20: For Electrical Components

    SPECIAL TOOLS INFO Rod puller Cylinder cup installer P/N. YM-01437 P/N. 90890-01996 This tool is used to install the master cylinder This tool is used to pull up the fork damper kit. Drive chain cutter P/N. YM-33858 FOR ELECTRICAL COMPONENTS This tool is used to cut and join the drive chain.
  • Page 21 INFO 1 - 8...

  • Page 22: Chapter 2. Specifications

    SPEC GENERAL SPECIFICATIONS SPECIFICATIONS GENERAL SPECIFICATIONS Model TTR250L(C) Model code: 5GF1 5GF2 Dimensions: Overall length 2,095 mm (82.5 in) Overall width 835 mm (32.9 in) Overall height 1,260 mm (49.6 in) Seat height 915 mm (36.0 in) Wheelbase 1,405 mm (55.3 in) Minimum ground clearance 305 mm (12.0 in)
  • Page 23 SPEC GENERAL SPECIFICATIONS Model TTR250L(C) Carburetor: Type / quantity Y30P/1 Manufacturer TEIKEI Spark plug: Type CR9E/U27ESR-N Manufacturer NGK/DENSO Spark plug gap 0.7 ~ 0.8 mm (0.028 ~ 0.031 in) Clutch type: Wet, multiple-disc Transmission: Primary reduction system Spur gear Primary reduction ratio 74/24 (3.083)
  • Page 24 SPEC GENERAL SPECIFICATIONS Model TTR250L(C) Brake: Front brake type Single disc brake operation Right hand operation Rear brake type Single disc brake operation Right foot operation Suspension: Front suspension Telescopic fork Rear suspension Swingarm (link suspension) Shock absorber: Front shock absorber...

  • Page 25: Maintenance Specifications

    SPEC MAINTENANCE SPECIFICATIONS MAINTENANCE SPECIFICATIONS ENGINE Model TTR250L(C) Cylinder head: Volume 21.6 ~ 22.2 cm <Warp <0.03 mm (0.0012 in)> limit> *Lines indicate straightedge measurement. Cylinder: Material Aluminum alloy Sleeve type Sleeveless, surface honing Bore size 72.97 ~ 73.02 mm (2.8728 ~ 2.8748 in) *Measuring point 40 mm (1.57 in)
  • Page 26 SPEC MAINTENANCE SPECIFICATIONS Model TTR250L(C) Valve, valve seat, valve guide: Valve clearance (cold) 0.09 ~ 0.19 mm (0.004 ~ 0.007 in) 0.19 ~ 0.27 mm (0.007 ~ 0.011 in) Valve dimensions: Seat Width Head Diameter Face Width Margin Thickness “A” head diameter 28.4 ~ 28.6 mm (1.118 ~ 1.126 in)
  • Page 27 SPEC MAINTENANCE SPECIFICATIONS Model TTR250L(C) Valve spring: Free length 35.59 mm (1.40 in) 35.59 mm (1.40 in) <Limit> <33.81 mm (1.33 in)> <33.81mm (1.33 in)> Spring rate IN-K1 18.9 N/mm (1.93 kg/mm, 107.92 lb/in) IN-K2 24.5 N/mm (2.50 kg/mm, 139.9 lb/in) EX-K1 18.9 N/mm (1.93 kg/mm, 107.92 lb/in)
  • Page 28 SPEC MAINTENANCE SPECIFICATIONS Model TTR250L(C) Piston rings: Top ring Type Barrel Dimensions (B × T) 1.0 × 3.1 mm (0.039 × 0.122 in) End gap (installed) 0.20 ~ 0.35 mm (0.008 ~ 0.014 in) <Limit> <0.4 mm (0.016 in)> Side clearance (installed) 0.04 ~ 0.08 mm (0.0016 ~ 0.0031 in)
  • Page 29 SPEC MAINTENANCE SPECIFICATIONS Model TTR250L(C) Clutch release method Inner push, cam push <Push rod bending limit> <0.5 mm (0.020 in)> Transmission: <Main axle deflection limit> <0.08 mm (0.003 in)> <Drive axle deflection limit> <0.08 mm (0.003 in)> Shifter: Shifter type...
  • Page 30 SPEC MAINTENANCE SPECIFICATIONS TIGHTENING TORQUES Tightening torque Thread Part to be tightened Part name Q’ty Remarks size m·kg ft·lb Cylinder head (camshaft cap) Flange bolt Spark plug – M10S Cylinder head (exhaust pipe) Stud bolt Cylinder head Flange bolt Cylinder head Flange bolt Cylinder head Cylinder head cover...
  • Page 31 SPEC MAINTENANCE SPECIFICATIONS Tightening torque Thread Part to be tightened Part name Q’ty Remarks size m·kg ft·lb Push rod 2 Push lever Screw Clutch cable holder Flange bolt Drive sprocket 11.0 Lever stopper Bolt Shift pedal Bolt Starter motor Flange bolt Straight Drain plug screw plug...
  • Page 32 SPEC MAINTENANCE SPECIFICATIONS Tightening sequence Cylinder head Lubrication chart Oil cleaner Cylinder head Drive axle Relief valve Oil pump Camshaft Main axle Crankshaft Oil strainer Oil pan 2 - 11...

  • Page 33: Chassis

    SPEC MAINTENANCE SPECIFICATIONS CHASSIS Model TTR250L(C) Steering system: Steering bearing type Taper roller bearing Front suspension: Front fork travel 280 mm (11.02 in) Fork spring free length 472 mm (18.6 in) <Limit> <462 mm (18.2 in)> Spring rate (K1) 4 N/mm (0.41 kg/mm 22.8 lb/in)
  • Page 34 SPEC MAINTENANCE SPECIFICATIONS Model TTR250L(C) Drive chain: Type / manufacturer 520V2 / DAIDO No. of links Chain free play 35 ~ 50 mm (1.4 ~ 2.0 in) Sealed type chain Front disc brake: Type Single Disc outside diameter × thickness 245.0 ×...
  • Page 35 SPEC MAINTENANCE SPECIFICATIONS TIGHTENING TORQUES Tightening torque Part to be tightened Thread size Remarks m·kg ft·lb Engine (front upper) and engine stay Engine stay (front upper) and frame Engine (front under) and frame Engine (rear under) and frame Engine (rear middle) and frame Engine stay (rear middle) and frame Engine (rear upper) and engine stay Engine stay (rear upper) and frame...
  • Page 36 SPEC MAINTENANCE SPECIFICATIONS Tightening torque Part to be tightened Thread size Remarks m·kg ft·lb Ignition coil and frame Battery box and frame Side cover and frame Seat and frame Rear fender and frame Helmet holder and frame Taillight and rear fender Front hub and front disk Front wheel shaft and front fork Axle holder and front fork...

  • Page 37: Electrical

    SPEC MAINTENANCE SPECIFICATIONS ELECTRICAL Model TTR250L(C) Voltage: 12 V Ignition system: Ignition timing (B.T.D.C.) 10° at 1,300 r/min Advanced timing (B.T.D.C.) 31° at 8,500 r/min Advancer type Digital type C.D.I.: 190 ~ 230 Ω at 20 °C (68 °F) / Yellow – Blue Pickup coil resistance / color C.D.I.
  • Page 38 SPEC MAINTENANCE SPECIFICATIONS Model TTR250L(C) Starter relay: Model / manufacturer MS5D-361 / JIDECO Amperage rating 100 A 3.9 ~ 4.7 Ω at 20 °C (68 °F) Coil winding resistance 2 - 17...

  • Page 39: General Torque Specifications

    SPEC GENERAL TORQUE SPECIFICATIONS GENERAL TORQUE SPECIFICATIONS General torque This chart specifies torque for standard fas- specifications teners with standard I.S.O. pitch threads. (Nut) (Bolt) Torque specifications for special compo- m • kg ft • lb nents or assemblies are included in the 10 mm 6 mm applicable sections of this book.

  • Page 40: Lubrication Points And Lubricant Types

    Transmission gear (wheel / pinion) Axle (main / drive) Shift cam Shift fork / guide bar Shift shaft (1, 2) Matching surface Yamaha Bond No. ® (cylinder head and cylinder head cover) 1215 Yamaha Bond No. Crankcase matching surface ®...

  • Page 41: Chassis

    SPEC LUBRICATION POINTS AND LUBRICANT TYPES CHASSIS Lubrication Point Lubricant Type Front wheel oil seal lips Rear wheel oil seal lips Bearing, oil seal lips (connecting rod) Oil seal lips, bearings (relay arm and frame) Pivot shaft (swingarm) Bearing (relay arm and rear shock absorber) Bolts, collars, seal lips (relay arm and frame) Bolt, collars (relay arm and connecting rod) Bolt (connecting rod and swingarm)

  • Page 42: Lubrication Diagram

    SPEC LUBRICATION DIAGRAM LUBRICATION DIAGRAM 1 Oil pump 2 Push lever 3 Delivery pipe 2 - 21...
  • Page 43 SPEC LUBRICATION DIAGRAM 1 Relief valve 2 Crankshaft 3 Main axle 4 Drive axle 5 Delivery pipe 6 Push lever 7 Camshaft 2 - 22...
  • Page 44 SPEC LUBRICATION DIAGRAM 1 Oil cleaner 2 Check bolt 3 Oil pump 4 Oil strainer 2 - 23...

  • Page 45: Cable Routing

    SPEC CABLE ROUTING CABLE ROUTING Å Cut the end of the band after Ì Pass the spark plug lead over the 1 Throttle cable 2 Wire sub lead tightening. leads. ı Do not put this portion of the Ó Install the clamp with its end fac- 3 A.C.
  • Page 46 SPEC CABLE ROUTING Å Install the clamp with its open side facing outward. 1 Rectifier/regulator lead ı Tighten the main switch lead to the rectifier/regulator. 2 Main switch lead Ç Tighten the ignition coil lead to the ignition coil. 3 Ignition coil lead Î...
  • Page 47 SPEC CABLE ROUTING Make sure the projection on the front fork is placed in the slot in the speedometer gear unit. Ò Pass the wireharness over the fuel tank bracket. ˜ Pass the wireharness under the regulator lead coupler. Make sure the coupler does not go over the right side.
  • Page 48 SPEC CABLE ROUTING Å The pipe portion of the brake hose should touch the projection 1 Clutch switch lead 2 Clutch cable on the master cylinder. ı Install the brake hose with its white mark facing forward. 3 Handlebar switch (left) lead Ç...
  • Page 49 SPEC 2 - 28...

  • Page 50: Periodic Inspection And Adjustment

    INTRODUCTION/ PERIODIC MAINTENANCE/LUBRICATION PERIODIC INSPECTION AND ADJUSTMENT INTRODUCTION This chapter includes all information necessary to perform recommended inspections and adjustments. These preventive maintenance procedures, if followed, will ensure more reli- able vehicle operation and a longer service life. The need for costly overhaul work will be greatly reduced.
  • Page 51 • Lubricate with molybdenum disulfide grease. point : Since these items require special tools, data and technical skills, they should be serviced by a Yamaha dealer. NOTE: The air filter needs more frequent service if you are riding in unusually wet or dusty areas.

  • Page 52: Seat, Fuel Tank And Covers

    SEAT, FUEL TANK AND COVERS SEAT, FUEL TANK AND COVERS REMOVAL WARNING Securely support the motorcycle so there is no danger of it falling over. 1.Remove: Side cover (left) 1 2.Remove: Side cover (right) 1 NOTE: When removing the side covers (left and right), remove the bolt 2.

  • Page 53: Installation

    SEAT, FUEL TANK AND COVERS 5.Disconnect: Fuel hose 1 NOTE: Place a rag on the engine to absorb any spil fuel. WARNING Gasoline is highly flammable. Avoid spilling fuel on the hot engine. 6.Disconnect: Fuel tank breather hose 1 7.Remove: Fuel tank bracket bolts 1 8.Remove: Band 1...
  • Page 54 SEAT, FUEL TANK AND COVERS 2.Install: Seat 1 Side covers (left and right) Bolt (seat): 7 Nm (0.7 m • kg, 5.1 ft • lb) Bolt (side cover): 7 Nm (0.7 m • kg, 5.1 ft • lb) 3 - 5...

  • Page 55: Engine

    VALVE CLEARANCE ADJUSTMENT ENGINE VALVE CLEARANCE ADJUSTMENT NOTE: The valve clearance must be adjusted when the engine is cool to the touch. Adjust the valve clearance when the pis- ton is at the Top Dead Center (T.D.C.) on compression stroke. WARNING Securely support the motorcycle so there is no danger of it falling over.
  • Page 56 VALVE CLEARANCE ADJUSTMENT Align the “T” mark 1 on the rotor with stationary pointer 2 on the crankcase cover. When the “T” mark is aligned with the stationary pointer, the piston is at Top Dead Center (T.D.C.). NOTE: T.D.C. on compression stroke check: Both cam lobes must have a valve clear- ance when the rotor match mark 1 is aligned with the stationary pointer match...
  • Page 57 VALVE CLEARANCE ADJUSTMENT 6.Remove: Exhaust pipe 1 7.Loosen: Cap bolt 1 8.Remove: Cam chain tensioner 2 9.Remove: Camshaft caps 1 Camshafts 2 NOTE: Refer to “ENGINE DISASSEMBLY-CYLIN- DER HEAD, CAMSHAFTS, CYLINDER AND PISTON” in CHAPTER 4. Fasten a wire to the cam chain to prevent it from falling into the crankcase.
  • Page 58 VALVE CLEARANCE ADJUSTMENT INTAKE Å ı INSTALLED PAD NUMBER MEASURED CLEARANCE 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240 0.00 ~ 0.04 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 0.05 ~ 0.08 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 0.09 ~ 0.17...
  • Page 59 VALVE CLEARANCE ADJUSTMENT Pad availability: Pad range 25 increments 1.20 mm No. 120 (0.047 in) Pads are stepped in 0.05 mm (0.002 in) No. 240 2.40 mm increments (0.094 in) NOTE: Thickness of each pad is marked on the pad face that contacts the valve lifter (not the cam).
  • Page 60 VALVE CLEARANCE ADJUSTMENT 11.Install: Camshafts 1 Timing chain 2 Camshaft caps Bolt (camshaft caps, cam chain tensioner): 10 Nm (1.0 m • kg, 7.2 ft • lb) Cap bolt (cam chain tensioner): 8 Nm (0.8 m • kg, 5.8 ft • lb) NOTE: Install the exhaust camshaft first.
  • Page 61 VALVE CLEARANCE ADJUSTMENT With the rod fully wound, install the gas- ket and the chain tensioner 2, and tighten the bolt 3 to the specified torque. Bolt 3 (chain tensioner): 10 Nm (1.0 m • kg, 7.2 ft • lb) Release the screwdriver, check that the tensioner rod to comes out and tighten the gasket and the cap bolt 4 to the spec-...

  • Page 62: Timing Chain Adjustment

    VALVE CLEARANCE ADJUSTMENT/TIMING CHAIN ADJUSTMENT/IDLING SPEED ADJUSTMENT 15.Install: Exhaust pipe Engine mount stay 1, 2: 30 Nm (3.0 m • kg, 22 ft • lb) Engine mount stay 3: 64 Nm (6.4 m • kg, 46 ft • lb) Nut 4, 5: 20 Nm (2.0 m •...

  • Page 63: Idling Speed Adjustment

    IDLING SPEED ADJUSTMENT/ THROTTLE CABLE FREE PLAY ADJUSTMENT 4.Adjust: Engine idling speed ********************************* Adjustment steps: Turn in the pilot screw 1 until it is lightly seated. Turn out the pilot screw for the specified number of turns. Pilot screw: 1-1/2 turns out Turn the throttle stop screw 2 in or out until specified idling speed is obtained.

  • Page 64: Spark Plug Inspection

    THROTTLE CABLE FREE PLAY ADJUSTMENT/ SPARK PLUG INSPECTION 1st step: Loosen the locknut 3 on throttle cable #2. Turn the adjuster 4 in or out until all slack is removed from throttle cable #2. 2nd step: Loosen the locknut 5 on throttle cable #1. Turn the adjuster 6 in or out until the specified free play is obtained.
  • Page 65 SPARK PLUG INSPECTION 3.Inspect: Spark plug type Incorrect → Replace. Standard spark plug: CR9E (NGK), U27ESR-N (DENSO) 4.Inspect: Electrode 1 Wear/damage → Replace. Insulator 2 Abnormal color → Replace. Normal color is a medium-to-light tan color. 5.Clean the spark plug with a spark plug cleaner or wire brush.

  • Page 66: Ignition Timing Check

    IGNITION TIMING CHECK IGNITION TIMING CHECK NOTE: Engine idling speed and throttle cable free play should be adjusted properly before checking the ignition timing. 1.Start the engine and let it warm up for several minutes, then stop the engine. 2.Attach: Inductive tachometer Timing light To spark plug lead.

  • Page 67: Compression Pressure Measurement

    COMPRESSION PRESSURE MEASUREMENT COMPRESSION PRESSURE MEASUREMENT NOTE: Insufficient compression pressure will result in performance loss. 1.Check: Valve clearance Out of specification → Adjust. Refer to “VALVE CLEARANCE ADJUST- MENT”. 2.Start the engine and let it warm up for several minutes. 3.Stop the engine.

  • Page 68: Engine Oil Level Inspection

    COMPRESSION PRESSURE MEASUREMENT/ ENGINE OIL LEVEL INSPECTION Compression pressure (at sea level): Standard: 1,200 kPa (12 kg/cm , 174 psi) Minimum: 1,000 kPa (10 kg/cm , 145 psi) Maximum: 1,300 kPa (13 kg/cm , 189 psi) If pressure falls below the minimum level: 1) Squirt a few drops of oil into the affected cylinder.

  • Page 69: Engine Oil Replacement

    ENGINE OIL LEVEL INSPECTION/ ENGINE OIL REPLACEMENT 4.Inspect: Oil level Oil level should be between maximum 1 and minimum 2 marks. Low oil level → Add oil to proper level. NOTE: Wait a few minutes until level settles before inspecting. Recommended oil: SAE 20W40 type SE motor oil or SAE 10W30 type SE motor oil...
  • Page 70 ENGINE OIL REPLACEMENT Engine oil replacement (without oil filter) 1.Place the motorcycle on a level place. 2.Warm up the engine for several minutes, then stop the engine. Then place a recep- tacle under the drain plug. 3.Remove: Drain plug 1 4.Drain: Engine oil 5.Remove:...
  • Page 71 ENGINE OIL REPLACEMENT 11.Inspect: Oil level Refer to “ENGINE OIL LEVEL INSPEC- TION”. Oil pressure Refer to “OIL PRESSURE INSPECTION”. Oil leaks Engine oil replacement (with oil filter) 1.Place the motorcycle on a level place. 2.Warm up the engine for several minutes, then stop the engine.
  • Page 72 ENGINE OIL REPLACEMENT 7.Inspect: O-ring Damage → Replace. 8.Clean: Oil filter Clean it with solvent. Clog/damage → Replace. 9.Install: Oil filter 1 CAUTION: Install the oil filter as shown. Oil filter cover Drain plug (crankcase) Bolt (oil filter): 10 Nm (1.0 m • kg, 7.2 ft • lb) Drain plug (crankcase): 20 Nm (2.0 m •...

  • Page 73: Oil Pressure Inspection

    OIL PRESSURE INSPECTION/ CLUTCH ADJUSTMENT OIL PRESSURE INSPECTION 1.Remove: Oil check bolt 1 2.Start the engine and keep it idling for sev- eral minutes. 3.Inspect: Oil condition of the bleed hole Oil flows out → Oil pressure is good. No oil comes out → Oil pressure is bad. CAUTION: If no oil comes out after a lapse of one minute, turn off the engine immediately so...

  • Page 74: Air Filter Cleaning

    CLUTCH ADJUSTMENT/ AIR FILTER CLEANING 2nd step: Loosen the locknut 2. Turn the adjuster 1 in or out until the cor- rect free play is obtained. Turning in → Free play is increased. Turning out → Free play is decreased. Tighten the locknut 2.
  • Page 75 AIR FILTER CLEANING 4.Clean: Air filter element Clean it with solvent. NOTE: After cleaning, remove the remaining sol- vent by squeezing the element. CAUTION: Do not twist the filter element when squeezing the filter element. WARNING Never use low flash point solvents such as gasoline to clean the air filter element.

  • Page 76: Spark Arrester Cleaning

    SPARK ARRESTER CLEANING SPARK ARRESTER CLEANING 1.Select a well-ventilated area free of com- bustible materials and make sure the exhaust and muffler are cool. 2.Remove: Spark arrester 1 3.Clean: Spark arrester with wire brush 4.Install: Spark arrester Bolt (spark arrester): 7 Nm (0.7 m •...

  • Page 77: Crankcase Breather Hose Inspection

    CRANKCASE BREATHER HOSE INSPECTION/ FUEL LINE INSPECTION/EXHAUST SYSTEM INSPECTION/ CRANKCASE BREATHER HOSE INSPECTION 1.Inspect: Breather hose 1 Cracks/damage → Replace. Check hose 2 Drain oil/water → Clean. FUEL LINE INSPECTION 1.Inspect: Fuel hose 1 Cracks/damage → Replace. EXHAUST SYSTEM INSPECTION 1.Inspect: Exhaust pipe Muffler...

  • Page 78: Chassis

    FRONT BRAKE ADJUSTMENT/ REAR BRAKE ADJUSTMENT CHASSIS FRONT BRAKE ADJUSTMENT 1.Check: Brake lever free play a Out of specification → Adjust. Free play: 2 ~ 5 mm (0.08 ~ 0.20 in) 2.Adjust: Brake lever free play ********************************* Adjustment steps: Loosen the locknut 1. Turn the adjuster 2 in or out until the specified free play is obtained.
  • Page 79 REAR BRAKE ADJUSTMENT 2.Adjust: Brake pedal height ********************************* Adjustment steps: Loosen the locknut 1. Turn the adjuster 2 in or out until the specified pedal height is obtained. Turning in Pedal height is increased. Turning out Pedal height is decreased. WARNING After adjusting the brake pedal height, visually check the adjuster end.

  • Page 80: Brake Fluid Level Inspection

    BRAKE FLUID LEVEL INSPECTION NB1A3008 BRAKE FLUID LEVEL INSPECTION NOTE: Position the motorcycle straight up when inspecting the fluid level. 1.Place the motorcycle on a level surface. NOTE: Place the motorcycle on its centerstand if a centerstand is equipped. If not, place a suit- able stand under the motorcycle.

  • Page 81: Air Bleeding (Hydraulic Brake System)

    AIR BLEEDING (HYDRAULIC BRAKE SYSTEM) NB1A3013 AIR BLEEDING (HYDRAULIC BRAKE SYSTEM) WARNING Bleed the brake system if: The system has been disassembled. A brake hose has been loosened or removed. The brake fluid is very low. The brake operation is faulty. A loss of braking performance may occur Å...

  • Page 82: Brake Pad Inspection

    AIR BLEEDING (HYDRAULIC BRAKE SYSTEM)/ BRAKE PAD INSPECTION/BRAKE HOSE INSPECTION Recommended fluid: Front: DOT #4 Rear: DOT #4 WARNING Check the operation of the brake after bleeding the brake system. ********************************* Å NB1A3009 BRAKE PAD INSPECTION 1.Activate the brake lever or brake pedal. 2.Inspect: Brake pad Wear indicator 1 nearly contacting brake...

  • Page 83: Brake Hose Inspection

    BRAKE HOSE INSPECTION/ DRIVE CHAIN SLACK ADJUSTMENT Å NB1A3012 BRAKE HOSE INSPECTION WARNING Securely support the motorcycle so there is no danger of it falling over. 1.Place the motorcycle on a level place. 2.Inspect: Brake hose(s) 1 Cracks/wear/damage → Replace. Å...
  • Page 84 DRIVE CHAIN SLACK ADJUSTMENT 2.Check: Drive chain slack a Out of specification → Adjust. Drive chain slack: 35 ~ 50 mm (1.38 ~ 1.97 in) with elevated rear wheel 3.Adjust: Drive chain slack ********************************* Adjustment steps: Remove the cotter pin 1 and loosen the axle nut 2.

  • Page 85: Drive Chain Lubrication

    DRIVE CHAIN LUBRICATION/ STEERING HEAD ADJUSTMENT DRIVE CHAIN LUBRICATION The chain consists of many parts which work against each other. If the chain is not maintained properly, it will wear out rap- idly, therefore, form the habit of periodi- cally servicing the chain. This service is especially necessary when riding in dusty conditions.
  • Page 86 STEERING HEAD ADJUSTMENT 5.Remove: Bolts (handlebar) 1 Nut (steering shaft) 2 Speedometer 3 Upper bracket 4 Pinch bolts (upper bracket) 6.Adjust: Steering head ********************************* Adjustment steps: Remove the lock washer 1. Remove the ring nut (upper) 2 and damper collar 3, then loosen the ring nut (lower) 4.

  • Page 87: Front Fork Inspection

    STEERING HEAD ADJUSTMENT/ FRONT FORK INSPECTION Check the steering stem by turning it lock to lock. If there is any binding, remove the steering stem assembly and inspect the steering bearings. Install the damper collar and ring nut (upper) 2 . Finger tighten the ring nut (upper) 2 , then align the slots of both ring nuts.

  • Page 88: Front Fork Adjustment

    FRONT FORK ADJUSTMENT 3.Check: Inner tube 1 Scratch/damage → Replace. Dust seal 2 Oil seal Excessive oil leakage → Replace. 4.Hold the motorcycle on upright position and apply the front brake. 5.Check: Operation Pump the front fork up and down for sev- eral times.
  • Page 89 FRONT FORK ADJUSTMENT Adjuster position: Standard: 13 clicks out Minimum: 20 clicks out Maximum: 1 click out from full turn in CAUTION: Always keep the adjustment level equal on both forks. Never attempt to turn the adjuster beyond the maximum or minimum set- ting.

  • Page 90: Rear Shock Absorber Adjustment

    FRONT FORK ADJUSTMENT/ REAR SHOCK ABSORBER ADJUSTMENT 4.Install: Air valve caps NB533012 REAR SHOCK ABSORBER ADJUSTMENT WARNING Securely support the motorcycle so there is no danger of it falling over. 1.Remove: Side cover (right) Battery box Seat Refer to “REAR SHOCK ABSORBER AND SWINGARM”...
  • Page 91 REAR SHOCK ABSORBER ADJUSTMENT Measurement length a: Standard: 228 mm (9.0 in) Minimum: 224 mm (8.8 in) Maximum: 236 mm (9.3 in) CAUTION: Never attempt to turn the adjuster beyond the maximum or minimum setting. Tighten the locknut. Locknut: 70 Nm (7.0 m • kg, 50 ft • lb) CAUTION: Always tighten the locknut against the spring adjuster and torque the locknut to...

  • Page 92: Tire Inspection

    REAR SHOCK ABSORBER ADJUSTMENT/ TIRE INSPECTION Rebound damping 1.Adjust: Rebound damping Turn the adjuster 1 in or out. Turning in → Rebound damping is harder. Turning out → Rebound damping is softer. Adjuster position: Standard: 8 clicks out Minimum: 16 clicks out Maximum: 1 click out from full turn in.
  • Page 93 TIRE INSPECTION Basic weight: With oil and full fuel 124 kg (273 lb) tank Maximum load- 90 kg (198 lb) except motorcycle* Cold tire pres- Front Rear sure 100 kPa 100 kPa Off-road (1 kg/cm (1 kg/cm riding* 14.5 psi) 14.5 psi) * Load is the total weight of rider, and accesso- ries.
  • Page 94 Be sure to install the correct tube when using tube type tires. After extensive tests, the tires mentioned below have been approved by Yamaha motor Co., Ltd. for this model. No guaran- tee for handling characteristics can be given if tire combinations other than what is approved are used on this motor- cycle.

  • Page 95: Wheel Inspection

    WHEEL INSPECTION/SPOKES INSPECTION AND TIGHTENING/CABLE INSPECTION AND LUBRICATION NA2A3016 WHEEL INSPECTION 1.Inspect: Wheels Damage/bends → Replace. NOTE: Always balance the wheel when a tire or wheel has been changed or replaced. WARNING Never attempt even small repairs to the wheel. NB2A3017 SPOKES INSPECTION AND TIGHTENING 1.Inspect:...

  • Page 96: Lever And Pedal Lubrication

    CABLE INSPECTION AND LUBRICATION/LEVER AND PEDAL LUBRICATION/SIDESTAND LUBRICATION 1.Inspect: Cable sheath Damage → Replace. 2.Check: Cable operation Unsmooth operation → Lubricate. Recommended lubricant: SAE 10W30 motor oil NOTE: Hold cable end high and apply several drops of lubricant to cable. NB3A3019 LEVER AND PEDAL LUBRICATION Lubricate the lever and pedal at their pivot-...

  • Page 97: Electrical

    BATTERY INSPECTION ELECTRICAL BATTERY INSPECTION NOTE: Since the MF battery is of a sealed-type construction, it is impossible to measure the specific gravity of the electrolyte in order to check the state of charge in the bat- tery. Therefore, to check the state of charge in the battery, voltage must be measured at the battery terminals.
  • Page 98 BATTERY INSPECTION WARNING Battery electrolyte is dangerous; it contains sulfuric acid and therefore is poisonous and highly caustic. Always follow these preventive measures: Avoid bodily contact with electrolyte as it can cause severe burns or permanent eye injury. Wear protective eye gear when handling or working near batteries.
  • Page 99 BATTERY INSPECTION 4.Check: Battery condition ********************************* Battery condition checking steps: Connect a digital volt meter to the battery terminals. Tester (+) lead → Battery (+) terminal. Tester (–) lead → Battery (–) terminal. NOTE: The state of a discharged MF battery can be checked by measuring the open-circuit volt- age (the voltage measured with the positive terminal being disconnected).
  • Page 100 BATTERY INSPECTION Use special care so that charging clips are in full contact with the terminal and that they are not shorted. (A corroded clip of the charger may cause the battery to gen- erate heat at the contact area. A weak clip spring may cause sparks.) Before removing the clips from the bat- tery terminals, be sure to turn off the...
  • Page 101 BATTERY INSPECTION Charging method using a variable-current (voltage) type charger 3 - 52...
  • Page 102 BATTERY INSPECTION Charging method using a constant-voltage type charger Charging method using a constant-current type charger This type of charger cannot charge the MF battery. 3 - 53...
  • Page 103 BATTERY INSPECTION/FUSE INSPECTION 6.Inspect: Battery terminal Dirty terminal → Clean with wire brush. Poor connection → Correct. NOTE: After cleaning the terminals, apply grease lightly to the terminals. 7.Install: Battery 8.Connect: Battery leads CAUTION: Connect the positive lead first and then connect the negative lead.

  • Page 104: Fuse Inspection

    FUSE INSPECTION 2.Remove: Fuse 1 3.Inspect: Fuse ********************************* Inspection steps: Connect the pocket tester to the fuse and check it for continuity. NOTE: Set the tester selector to “Ω × 1” position. Pocket tester: P/N. YU-03112 If the tester indicates ∞, the fuse is blown and needs to be replaced.

  • Page 105: Headlight Beam Adjustment

    HEADLIGHT BEAM ADJUSTMENT/ HEADLIGHT BULB REPLACEMENT HEADLIGHT BEAM ADJUSTMENT 1.Adjust: Headlight beam (vertical) Turn adjusting screw 1 To raise the beam counterclockwise. Turn adjusting screw 1 To lower the beam clockwise. HEADLIGHT BULB REPLACEMENT 1.Remove: Cover (headlight) 2.Disconnect: Headlight leads WARNING Keep flammable products and your hands away from the bulb while it is on, it will be...

  • Page 106: Chapter 4. Engine Overhaul

    ENGINE REMOVAL NB241000 ENGINE OVERHAUL ENGINE REMOVAL NOTE: It is not necessary to remove the engine in order to remove the following components. Cylinder head Cylinder Clutch Oil pump CDI magneto SEAT, FUEL TANK AND COVERS 1.Remove: Side covers Seat Fuel tank Refer to “SEAT, FUEL TANK AND COV- ERS”...

  • Page 107: Battery

    ENGINE REMOVAL NB241003 BATTERY 1.Remove: Battery 1 Refer to “BATTERY INSPECTION” in CHAPTER 3. EXHAUST PIPE 1.Loosen: Bolt 1 (clamp) 2.Remove: Mounting bolts 2 (front-upper) Nuts 3 (exhaust pipe) 3.Remove: Exhaust pipe CRANKCASE BREATHER HOSE 1.Disconnect: Crankcase breather hose 1 STARTER MOTOR 1.Disconnect: Gas chamber...

  • Page 108: Clutch Cable And Leads

    ENGINE REMOVAL CLUTCH CABLE AND LEADS 1.Remove: Clutch cable 1 ********************************* Removal steps: Loosen the locknuts 2, 4. Turn the adjuster 3, 5 enough to free the clutch cable. Unhook the cable end 6 from the clutch lever. Unhook the cable end from the clutch push lever 7.

  • Page 109: Footrest And Brake Pedal

    ENGINE REMOVAL 2.Remove: Nut 1 Lock washer 2 Drive sprocket 3 NOTE: Straighten the lock washer tab. Loosen the nut while applying the rear brake. First remove the drive chain on the rear sprocket side. FOOTREST AND BRAKE PEDAL 1.Remove: Footrest (right) 1 Brake pedal 2 ENGINE REMOVAL...

  • Page 110: Engine Disassembly

    ENGINE DISASSEMBLY NB342002 ENGINE DISASSEMBLY CYLINDER HEAD, CAMSHAFTS, CYLINDER AND PISTON 1.Remove: Cylinder head cover 1 Spark plug 2 2.Remove: Plugs (with O-ring) 3.Align: “T” mark on the rotor With the stationary pointer on the crank- case cover. ********************************* TDC alignment steps: Turn crankshaft clockwise...
  • Page 111 ENGINE DISASSEMBLY 6.Remove: Camshaft caps NOTE: Fasten a safety wire 1 to the timing chain to prevent it from falling into the crankcase. 7.Remove: Camshaft 1 (intake) Camshaft 2 (exhaust) Dowel pins 3 NOTE: Remove the camshaft cap bolts in a criss- cross pattern from outside to inside.
  • Page 112 ENGINE DISASSEMBLY 10.Remove: Dowel pins 1 Gasket 2 (cylinder head) Timing chain guide 3 (exhaust) Cylinder 4 11.Remove: Dowel pins 1 Gasket 2 (cylinder) 12.Remove: Piston pin circlip 1 Piston pin 2 Piston 3 NOTE: Before removing the piston pin circlip, cover the crankcase with a clean rag to prevent the circlip from falling into the crankcase cavity.

  • Page 113: Clutch, Oil Pump And Balancer Gear

    ENGINE DISASSEMBLY CLUTCH, OIL PUMP AND BALANCER GEAR NOTE: With the engine mounted, the clutch and oil pump can be maintained by removing the following parts. Footrest (right) Brake pedal 1.Remove: Crankcase cover 1 (right) NOTE: Working in a crisscross pattern, loosen the bolts 1/4 turn each.
  • Page 114 ENGINE DISASSEMBLY 5.Loosen: Nut 2 (clutch boss) NOTE: Loosen the nut (clutch boss) while holding the clutch boss with the universal clutch holder Universal clutch holder: P/N. YU-91042 6.Remove: Clutch boss 1 Thrust plate 2 Primary driven gear 3 Ball 4 Push rod 5 7.Straighten: Lock washer tab 1...

  • Page 115: Shift Shaft

    ENGINE DISASSEMBLY 11.Remove: Circlip 1 Collar 2 Circlip SHIFT SHAFT NOTE: With the engine mounted, the shift shaft can be maintained by removing the follow- ing parts. Footrest (right) Brake pedal Clutch Oil pump 1.Remove: Circlip 1 Shift lever 2 Stopper lever 3 Torsion spring 4 ROTOR AND STARTER DRIVES...
  • Page 116 ENGINE DISASSEMBLY 2.Remove: Generator cover 1 3.Remove: Starter idle gear 1 1 Shaft 2 Bearing 3 4.Remove: Crankcase cover 1 (left) NOTE: Working in a crisscross pattern, loosen the bolts 1/4 turn each. Remove them after all are loosened. 5.Remove: Starter idle gear 2 1 Push lever assembly 2 6.Remove:...

  • Page 117: Oil Filter

    ENGINE DISASSEMBLY CAUTION: Do not allow the rotor holder to touch the projection 3 on the rotor. 7.Remove: Rotor 1 Use the sheave holder 2 and rotor puller Rotor puller: P/N. 2K7-85555-00 8.Remove: Starter wheel gear 1 Woodruff key 2 Bearing Washer OIL FILTER...

  • Page 118: Balancer, Transmission And Shifter

    ENGINE DISASSEMBLY 2.Align: Shift cam segment 1 NOTE: Turn the shift cam to the position shown in the figure so that it does not contact the crankcase when separating the crankcase. 3.Remove: Crankcase CAUTION: The crankcase should be separated from right side.

  • Page 119: Crankshaft

    ENGINE DISASSEMBLY 3.Remove: Balancer shaft 1 Main axle shaft 2 Drive axle shaft 3 CRANKSHAFT 1.Remove: Crankshaft assembly 1 Use the crankcase separating tool 2. Crankcase separating tool: P/N. YU-01135-A NOTE: Tighten the tool holding bolts, but make sure that the tool body is vertical with the crankshaft.
  • Page 120 ENGINE DISASSEMBLY 2.Check: Valve sealing Leakage at valve seat → Inspect the valve face, valve seat and valve seat width. Refer to “INSPECTION AND REPAIR- VALVE SEAT”. ********************************* Checking steps: Pour a clean solvent 1 into the intake and exhaust ports. Check the valve sealing.

  • Page 121: Inspection And Repair

    INSPECTION AND REPAIR NB243001 INSPECTION AND REPAIR CYLINDER HEAD 1.Eliminate: Carbon deposit (from combustion chamber) Use rounded scraper 1. NOTE: Do not use a sharp instrument and avoid damaging or scratching: Spark plug thread Valve seat 2.Inspect: Cylinder head Scratches/damage → Replace. 3.Measure: Warpage Out of specification →...
  • Page 122 INSPECTION AND REPAIR 3.Measure: Valve seat width a Out of specification → Reface the valve seat. Valve seat width: Intake: 0.9 ~ 1.1 mm (0.035 ~ 0.043 in) Exhaust: 0.9 ~ 1.1 mm (0.035 ~ 0.043 in) ********************************* Measurement steps: Apply Mechanic’s blueing...
  • Page 123 INSPECTION AND REPAIR ********************************* Å Refacing steps: Å Valve seat is centered on the valve face but it is too wide. Valve seat cutter set Desired result To reduce valve 45° cutter seat width to lightly 60° cutter 1.0 mm (0.039 in). ı...
  • Page 124 INSPECTION AND REPAIR ********************************* Lapping steps: Apply a coarse lapping compound to the valve face. CAUTION: Be sure no compound enters the gap between the valve stem and guide. Apply a molybdenum disulfide oil to the valve stem. Install the valve into the cylinder head. Turn the valve until the valve face and valve seat are evenly polished, then clean off all compound.

  • Page 125: Valve And Valve Guide

    INSPECTION AND REPAIR NB243003 VALVE AND VALVE GUIDE 1.Measure: Stem-to-guide clearance Stem-to-guide clearance = Valve guide inside diameter a – Valve stem diameter b Out of specification → Replace valve guide. Stem-to-guide clearance: Intake: 0.010 ~ 0.037 mm (0.0004 ~ 0.0015 in) <Limit>: 0.08 mm (0.0031 in) Exhaust: 0.025 ~ 0.052 mm...

  • Page 126: Valve Spring

    INSPECTION AND REPAIR 3.Eliminate: Carbon deposit (from valve face) 4.Inspect: Valve face Pitting/wear → Grind the face. Valve stem end Mushroom shape or diameter larger than the body of the stem → Replace. 5.Measure: Margin thickness a Out of specification → Replace. Margin thickness: IN: 0.6 ~ 1.0 mm (0.02 ~ 0.04 in) EX: 0.8 ~ 1.2 mm (0.03 ~ 0.05 in)

  • Page 127: Camshaft

    INSPECTION AND REPAIR 2.Measure: Compressed force 1 (valve spring) Out of specification → Replace. Installed length Compressed force: Spring at 30.39 mm (1.20 in) 9.3 ~ 10.7 kg Intake (20.53 ~ 23.62 lb) 9.3 ~ 10.7 kg Exhaust (20.53 ~ 23.62 lb) 3.Measure: Spring tilt a Out of specification →...
  • Page 128 INSPECTION AND REPAIR 3.Measure: Runout (camshaft) Out of specification → Replace. Runout (camshaft): Less than 0.03 mm (0.0012 in) 4.Measure: Camshaft-to-cap clearance Out of specification → Measure bearing diameter (camshaft). Camshaft-to-cap clearance: 0.020 ~ 0.054 mm (0.0008 ~ 0.0021 in) ********************************* Measurement steps: Install the camshaft onto the cylinder...

  • Page 129: Valve Lifter

    INSPECTION AND REPAIR NB643006 VALVE LIFTER 1.Inspect: Valve lifters Scratches/damage → Replace both lifters and camshaft case. NB643007 TIMING CHAIN, SPROCKET AND CHAIN GUIDE 1.Inspect: Timing chain Stiff/cracks → Replace the timing chain and the sprockets as a set. 2.Inspect: Cam sprocket Wear/damage →...

  • Page 130: Cylinder And Piston

    INSPECTION AND REPAIR 4.Check: Timing chain tensioner movement ********************************* Checking steps: While pressing the tensioner rod lightly with fingers, use a thin screwdriver 1 and wind the tensioner rod up fully clockwise. When releasing the screwdriver by press- ing lightly with fingers, make sure that the tensioner rod will come out smoothly.
  • Page 131 INSPECTION AND REPAIR NOTE: Measure the cylinder bore “C” in parallel to and at right angles to the crankshaft. Then, find the average of the measure- ments. Cylinder bore “C”: 72.970 ~ 73.020 mm (2.873 ~ 2.875 in) <Limit: 73.1 mm (2.878 in) C = (X + Y)/2 If out of specification, rebore or replace the cylinder, and replace the piston and...

  • Page 132: Piston Ring

    INSPECTION AND REPAIR NB243009 PISTON RING 1.Measure: Side clearance Out of specification → Replace the piston and the piston rings as a set. NOTE: Clean carbon from piston ring grooves and rings before measuring side clearance. Side clearance: Top ring: 0.040 ~ 0.080 mm (0.0016 ~ 0.0031 in) 2nd ring:...

  • Page 133: Crankshaft

    INSPECTION AND REPAIR 2.Measure: Piston pin outside diameter Out of specification → Replace. Outside diameter (piston pin): 17.991 ~ 18.000 mm (0.7083 ~ 0.7087 in) 1 Micrometer 3.Measure: Piston pin bore inside diameter Out of specification → Replace. Piston pin bore inside diameter: 18.004 ~ 18.015 mm (0.7088 ~ 0.7093 in) CRANKSHAFT...

  • Page 134: Balancer Drive Gear And Balancer Gear

    INSPECTION AND REPAIR 2.Inspect: Crankshaft sprocket (cam chain sprocket) Wear/damage → Replace the crankshaft. 3.Inspect: Crankcase bearing 1 Abnormal noise/turn roughly/free play → Replace. Å Free play ********************************* Crankshaft reassembling point: The crankshaft 1 and the crank pin 2 oil passages must be properly interconnected with a tolerance of less than 1 mm (0.04 in).

  • Page 135: Primary Drive

    INSPECTION AND REPAIR NB243013 PRIMARY DRIVE 1.Inspect: Primary driven gear teeth 1 Clutch boss 2 Wear/damage → Replace. Excessive noise during operation → Replace. NB243014 CLUTCH 1.Inspect: Friction plate Damage/wear → Replace friction plates as a set. 2.Measure: Friction plate thickness Out of specification →...

  • Page 136: Transmission And Shifter

    INSPECTION AND REPAIR 7.Inspect: Dogs on the primary driven gear 1 Scoring/wear/damage → Deburr or replace. Clutch boss splines 2 → Scoring/wear/damage Replace clutch boss. NOTE: Scoring on the clutch housing dogs and the clutch boss splines will cause erratic opera- tion.
  • Page 137 INSPECTION AND REPAIR 2.Inspect: Shift cam groove 1 Shift cam segment 2 Wear/damage → Replace. 3.Check: Shift fork movement Unsmooth operation → Replace shift fork and/or guide bar. 4.Check: Guide bar Roll the guide bar on a flat surface. Bends → Replace. WARNING Do not attempt to straighten a bent guide bar.

  • Page 138: Oil Pump And Strainer

    INSPECTION AND REPAIR ********************************* Reassembling point: Press the 2nd pinion gear 1 in the main axle 2 as shown. ********************************* 7.Inspect: Shift shaft 1 1 Shift shaft 2 2 Stopper lever 3 Torsion spring 4 Cracks/damage → Replace. 8.Inspect: Shift lever 1 Torsion spring 2 Cracks/damage →...

  • Page 139: Electric Starter Drive

    INSPECTION AND REPAIR 2.Inspect: Oil pump driven gear 1 Oil pump 2 Wear/cracks/damage → Replace. 3.Inspect: Oil strainer Damage → Replace. NB243012 ELECTRIC STARTER DRIVE 1.Inspect: Starter idle gear 1 teeth 1 Starter idle gear 2 teeth 2 Burrs/chips/roughness/wear → Replace. 2.Inspect: Starter wheel gear (contacting surfaces)

  • Page 140: Crankcase

    INSPECTION AND REPAIR 5.Inspect: Pickup coil 1 Stator coil 2 Damage → Replace. NB243018 CRANKCASE 1.Thoroughly wash the case halves with mild solvent. 2.Throughly clean all the gasket mating sur- faces and crankcase mating surfaces. 3.Inspect: Crankcase Cracks/damage → Replace. Oil delivery passages Clog →...

  • Page 141: Engine Assembly And Adjustment

    ENGINE ASSEMBLY AND ADJUSTMENT ENGINE ASSEMBLY AND ADJUSTMENT CRANKSHAFT AND BALANCER 1 Bearing 8 Balancer gear 2 Woodruff key 9 Spring 3 Crankshaft assembly 0 Dowel pin 4 Woodruff key A Absorber plate 5 Bearing B Balancer weight 6 Bearings 7 Buffer boss 4 - 36...

  • Page 142: Crankshaft And Balancer Shaft

    ENGINE ASSEMBLY AND ADJUSTMENT CRANKSHAFT AND BALANCER SHAFT 1.Attach: Crankshaft installing tool Crank pot spacer 1: P/N. YU-01202 Adapter #12 2: P/N. YU-90062 Crankshaft installer set 3: P/N. YU-90050 2.Install: Crankshaft NOTE: Hold the connecting rod at top dead center with one hand while turning the nut of the installing tool with the other.

  • Page 143: Transmission

    ENGINE ASSEMBLY AND ADJUSTMENT TRANSMISSION 1 Drive sprocket 0 1st wheel gear 2 Oil seal A Bearing 3 Bearing B Bearing 4 Drive axle C 2nd pinion gear 5 2nd wheel gear D 5th pinion gear 6 5th wheel gear E 3rd/4th pinion gear 7 4th wheel gear F 6th pinion gear...

  • Page 144: Shifter

    ENGINE ASSEMBLY AND ADJUSTMENT SHIFTER 1 Shift shaft 1 7 Shift fork guide bar 2 Shift shaft 2 8 Shift cam 3 Oil seal 9 Torsion spring 4 Shift fork L 0 Shift lever assembly 5 Shift fork C A Stopper lever 6 Shift fork R B Torsion spring 4 - 39...

  • Page 145: Transmission And Shifter

    ENGINE ASSEMBLY AND ADJUSTMENT TRANSMISSION AND SHIFTER 1.Install: Neutral switch 2.Apply: Molybdenum disulfide oil (onto the drive axle, main axle and gears) 3.Install: Drive axle assembly 1 Main axle assembly 2 Circlip 3 Install the chamfered side 4 facing the gear 5.
  • Page 146 ENGINE ASSEMBLY AND ADJUSTMENT 6.Install: Shift cam 1 Shift fork C 2 Shift fork L 3 Shift fork R 4 Shift fork guide bar 5 NOTE: Install the shift forks with the embossed mark on each shift fork facing the right side of the engine.

  • Page 147: Crankcase

    ENGINE ASSEMBLY AND ADJUSTMENT CRANKCASE 1 Crankcase (right) 2 Dowel pin 3 Crankcase (left) 4 Drain bolt 5 Breather plate 2 6 Breather plate 1 7 Holder (clutch cable) 8 Breather hose 4 - 42...

  • Page 148: Crankcase (Right)

    ENGINE ASSEMBLY AND ADJUSTMENT CRANKCASE (RIGHT) 1.Apply: Sealant (onto mating surfaces of both case halves) ® Quick Gasket P/N. ACC-11001-05-01 NOTE: DO NOT ALLOW any sealant to come in contact with the oil gallery. 2.Install: Dowel pins 1 3.Fit the left crankcase onto the right case. Tap lightly on the case with a soft ham- mer.
  • Page 149 ENGINE ASSEMBLY AND ADJUSTMENT 2.Install: Torsion spring 1 Stopper lever 2 Washer 3 Shift lever 4 Circlip Cam chain Cam chain damper NOTE: Set the torsion spring 1 and stopper lever 2 at proper position. Install the torsion spring 5 fitting to the guide pin 6.

  • Page 150: Oil Pump

    ENGINE ASSEMBLY AND ADJUSTMENT OIL PUMP 1 Pump gear cover 2 Pump driven gear 3 Pump cover 4 Oil pump assembly 5 Oil strainer 4 - 45...

  • Page 151: Clutch

    ENGINE ASSEMBLY AND ADJUSTMENT CLUTCH 1 Clutch spring 9 Push rod 2 2 Pressure plate 0 Ball 3 Push plate A Push rod 1 4 Clutch plate B Primary driven gear 5 Friction plate C Primary drive gear 6 Clutch boss D Oil seal 7 Thrust plate E Bearing...

  • Page 152: Oil Pump

    ENGINE ASSEMBLY AND ADJUSTMENT OIL PUMP 1.Install: Gasket Oil pump assembly 1 Pump cover 2 Oil strainer 3 Bolts (oil pump): 6 Nm (0.6 m • kg, 4.3 ft • lb) 2.Install: Pump driven gear 1 Circlip 2 3.Install: Gear cover 1 CLUTCH 1.Install: Key 1...
  • Page 153 ENGINE ASSEMBLY AND ADJUSTMENT 4.Tighten: Nut 1 (clutch boss) NOTE: Tighten the nut (clutch boss) while holding the clutch boss with the universal clutch holder 2. Universal clutch holder: P/N. YM-91042 Nut 1 (clutch boss): 75 Nm (7.5 m • kg, 54 ft • lb) 5.Bend: Lock washer tabs (along nut flats)
  • Page 154 ENGINE ASSEMBLY AND ADJUSTMENT 9.Install: Push rod 1 1 Push plate 2 Pressure plate 3 Plain washer 4 Nut 5 Spring 6 Bolts 7 NOTE: Tighten the bolts 7 in a crisscross pattern. Bolt 7 (pressure plate): 8 Nm (0.8 m • kg, 5.8 ft • lb) 10.Check: Push lever position Push the push lever assembly in the direc-...

  • Page 155: Oil Filter

    ENGINE ASSEMBLY AND ADJUSTMENT 12.Install: Claw washer Lock washer 1 Nut 2 NOTE: Place a folded rag or aluminum plate between the teeth of the drive gear and primary driven gear. Take care not to damage the gear teeth. 13.Bend the lock washer tab along the nut flats.

  • Page 156: Rotor And Starter Drives

    ENGINE ASSEMBLY AND ADJUSTMENT ROTOR AND STARTER DRIVES 1 Starter idle gear 1 8 Plate washer 2 Bearing 9 Bearing 3 Shaft 1 0 Starter wheel gear 4 Bearing A Starter clutch 5 Washer B Rotor 6 Starter idle gear 2 C Stator coil 7 Bearing D Clamp...
  • Page 157 ENGINE ASSEMBLY AND ADJUSTMENT ROTOR AND STARTER DRIVES NOTE: Fasten a safety wire to the timing chain to prevent it from falling into the crankcase. 1.Apply: 4-stroke engine oil (onto journal and starter drives) 2.Install: Starter clutch Bolt 1 Bolt 1 (Starter clutch): 10 Nm (1.0 m •...
  • Page 158 ENGINE ASSEMBLY AND ADJUSTMENT 6.Install: Washer 1 Bolt 2 Bolt 2 (rotor): 60 Nm (6.0 m • kg, 43 ft • lb) NOTE: Tighten the bolt (rotor) while holding the rotor with the sheave holder 3. Sheave holder: P/N. YS-01880 CAUTION: Do not allow the rotor holder to touch the projections on the rotor.

  • Page 159: Cylinder And Piston

    ENGINE ASSEMBLY AND ADJUSTMENT CYLINDER AND PISTON 1 Cylinder 2 Dowel pin 3 O-ring 4 Cylinder gasket 5 Piston ring 6 Piston pin clip 7 Piston 8 Piston pin 4 - 54...

  • Page 160: Cylinder And Piston

    ENGINE ASSEMBLY AND ADJUSTMENT CYLINDER AND PISTON 1.Apply: 4-stroke engine oil (onto piston rings and piston pins) 2.Install: Piston rings NOTE: Be sure to install the rings so that manufac- turer’s marks or numbers are located on the top side of the rings. 3.Install: Piston 1 Piston pin 2...
  • Page 161 ENGINE ASSEMBLY AND ADJUSTMENT 6.Install: O-ring 1 7.Install: Cylinder NOTE: Install the cylinder with one hand while compressing the piston ring with the other hand. 8.Install: Timing chain guide 1 (exhaust) Dowel pins 2 Gasket 3 (cylinder head) 4 - 56...

  • Page 162: Cylinder Head

    ENGINE ASSEMBLY AND ADJUSTMENT CYLINDER HEAD 1 Mount rubber 2 Cylinder head cover gasket 3 Cylinder head assembly 4 Camshaft cap 5 Camshaft cap 6 Dowel pin 7 Circlip 8 Valve guide 9 Spark plug 0 Cylinder head gasket 4 - 57...

  • Page 163: Valve, Camshaft And Cam Chain

    ENGINE ASSEMBLY AND ADJUSTMENT VALVE, CAMSHAFT AND CAM CHAIN 1 Timing chain guide (intake) 0 Adjusting pad 2 Camshaft (intake) A Valve cotter 3 Camshaft (exhaust) B Valve retainer 4 Cam sprocket C Oil seal 5 Timing chain D Valve spring 6 Timing chain guide (exhaust) E Spring seat 7 Stopper guide...

  • Page 164: Valve And Camshaft

    ENGINE ASSEMBLY AND ADJUSTMENT VALVE AND CAMSHAFT 1.Deburr: Valve stem end Use an oil stone to smooth the stem end. 2.Apply: Molybdenum disulfide oil (onto valve stem 1 and oil seal 2) 3.Install: Valve 1 Spring seat 2 Oil seal 3 Valve spring 4 Valve retainer 5 (into cylinder head)
  • Page 165 ENGINE ASSEMBLY AND ADJUSTMENT 4.Install: Valve cotters 1 NOTE: Install the valve cotters while compressing the valve spring with the valve spring com- pressor 2. Valve spring compressor: P/N. YM-04019 5.Secure the valve cotters onto the valve stem by tapping lightly with a piece of wood.

  • Page 166: Cylinder Head

    ENGINE ASSEMBLY AND ADJUSTMENT CYLINDER HEAD 1.Install: Cylinder head 1 Bolts 1 ~ 4 (cylinder head): 40 Nm (4.0 m • kg, 29 ft • lb) Nuts 5, 6 (cylinder head): 20 Nm (2.0 m • kg, 14 ft • lb) Bolts 7, 8 (cylinder head): 10 Nm (1.0 m •...
  • Page 167 ENGINE ASSEMBLY AND ADJUSTMENT CAUTION: The bolts (camshaft caps) must be tight- ened evenly or damage to the cylinder head, camshaft caps and camshaft will result. 5.Install: Cam sprockets ********************************* Installing steps: Turn the crankshaft clockwise until the TDC mark 1 is aligned with the stationary pointer 2.

  • Page 168: Remounting Engine

    ENGINE ASSEMBLY AND ADJUSTMENT With the rod fully wound, install the gas- ket and the chain tensioner 2, and tighten the bolts 3 to the specified torque. Bolt 3 (chain tensioner): 10 Nm (1.0 m • kg, 7.2 ft • lb) Release the screwdriver, check if the ten- sioner rod comes out and tighten the gas- ket and the cap bolt to the specified...
  • Page 169 ENGINE ASSEMBLY AND ADJUSTMENT NOTE: Install all the bolts and nuts first, and then tighten the bolts and nuts to specifications. Bracket bolts: 23 Nm (2.3 m • kg, 17 ft • lb) Mounting bolts: 64 Nm (6.4 m • kg, 46 ft • lb) 2.Tighten: Bolt 1 Stay bolts (cylinder head-stay):...
  • Page 170 ENGINE ASSEMBLY AND ADJUSTMENT 6.Bend: Lock washer tabs (along nut flats) 7.Adjust: Drive chain slack Refer to “DRIVE CHAIN SLACK ADJUST- MENT” in CHAPTER 3. Drive chain slack: 35 ~ 50 mm (1.38 ~ 1.97 in) 8.Install: Crankcase cover 2 1 Shift pedal 2 Bolt (crankcase cover 2): 10 Nm (1.0 m •...
  • Page 171 ENGINE ASSEMBLY AND ADJUSTMENT 10.Apply: Lithium soap base grease (onto the O-ring on starter motor) 11.Install: Starter motor Bolts (starter motor): 10 Nm (1.0 m • kg, 7.2 ft • lb) 12.Connect: Starter motor lead 1 Ground lead 2 13.Install: Gas chamber Refer to “ENGINE REMOVAL”.
  • Page 172 ENGINE ASSEMBLY AND ADJUSTMENT 19.Install: Exhaust pipe 1 Engine stay 2 Nuts (exhaust pipe): 20 Nm (2.0 m • kg, 14 ft • lb) Bolt (clamp): 20 Nm (2.0 m • kg, 14 ft • lb) Nuts (stay-frame): 30 Nm (3.0 m • kg, 22 ft • lb) Nut (stay-engine): 64 Nm (6.4 m •...
  • Page 173 4 - 68...

  • Page 174: Chapter 5. Carburetor

    CARB CARBURETOR CARBURETOR CARBURETOR 1 Throttle arm assembly SPECIFICATIONS 2 Jet needle set 3 Throttle valve ID MARK 5GF1 00 4 Pump lever MAIN JET (M.J.) #137 5 Starter plunger assembly PILOT JET (P.J.) 6 Needle valve set JET NEEDLE (J.N.) #5C9C-3/5 7 One-way valve NEEDLE JET (N.J.)

  • Page 175: Removal

    CARB CARBURETOR REMOVAL 1.Remove: Side covers Seat Fuel tank Refer to “SEAT, FUEL TANK AND COV- ERS” in CHAPTER 3. 2.Drain: Fuel 1 (float chamber) Refer to “ENGINE REMOVAL” in CHAP- TER 4. 3.Loosen: Clamps 2 (carburetor joint) 4.Remove: Bolts (air filter case) 5.Loosen: Locknuts 1 6.Disconnect:...

  • Page 176: Disassembly

    CARB CARBURETOR DISASSEMBLY NOTE: The following parts can be cleaned and inspected without disassembly. Starter plunger Throttle stop screw Pilot screw 1.Disconnect: Starter plunger assembly 1 2.Remove: Float chamber 1 Pilot screw 2 3.Remove: Baffle plate 1 Float pin 2 Float 3 Needle valve assembly 4 NOTE:...
  • Page 177 CARB CARBURETOR 5.Remove: Cap (carburetor mixing chamber body) 1 6.Remove: Screw (throttle arm) 1 7.Remove: Screws (throttle valve) 1 8.Remove: Throttle valve 1 Ring 2 Jet needle 3 Needle holder 4 Spring 5 9.Remove: Cover assembly 1 Spring 2 Diaphragm 3 O-ring 4 5 - 4...

  • Page 178: Inspection

    CARB CARBURETOR INSPECTION 1.Inspect: Carburetor mixing chamber body Carburetor float chamber body Contamination → Blow out passages with compressed air. NOTE: Use a petroleum based solvent for cleaning. (Do not use any caustic carburetor cleaning solution.) Blow out all passages and jets with com- pressed air.
  • Page 179 CARB CARBURETOR 5.Inspect: Valve seat 1 Needle valve 2 O-ring 3 Damage/wear → Replace as a set. NOTE: Always replace the needle valve and valve seat as a set. 6.Inspect: Starter plunger 1 Bends/wear/damage → Replace. Spring 2 Damage → Replace. 7.Inspect: Diaphragm 1 Tears/damage →...

  • Page 180: Assembly

    CARB CARBURETOR ASSEMBLY Reverse the “DISASSEMBLY” procedures. Note the following points. CAUTION: Before reassembling, wash all the parts in clean petroleum based solvent. Always use a new gasket. 1.Install: Main nozzle 1 Main jet 2 Pilot jet 3 2.Install: Valve seat 1 3.Install: Float 1 Needle valve assembly 2...
  • Page 181 CARB CARBURETOR 5.Install: O-ring 1 Diaphragm 2 Spring 3 Cover assembly 4 6.Install: Starter plunger assembly 1 7.Install: Throttle valve 1 Ring 2 Jet needle 3 8.Install: Throttle valve 1 Throttle arm 2 9.Install: Cap (mixing chamber assembly) 1 5 - 8...

  • Page 182: Installation

    CARB CARBURETOR 10.Install: Air vent hose 1 Fuel hose Air vent hose INSTALLATION 1.Install: Carburetor assembly Refer to “ENGINE REMOVAL” in CHAP- TER 4. 2.Install: Throttle cables 1 Refer to “CABLE ROUTING” in CHAPTER 3.Adjust: Throttle cable free play Refer to “THROTTLE CABLE FREE PLAY ADJUSTMENT”...

  • Page 183: Fuel Level Adjustment

    CARB CARBURETOR FUEL LEVEL ADJUSTMENT 1.Place the motorcycle on a level place. 2.Use a suitable stand under the frame and engine to ensure that the carburetor is positioned vertically. 3.Connect the fuel level gauge 1 to the float chamber drain pipe. Fuel level gauge: P/N.

  • Page 184: Throttle Valve Position

    CARB CARBURETOR THROTTLE VALVE POSITION 1.Adjust: Throttle valve position ********************************* Adjustment steps: Loosen the locknut 1. Turn the throttle grip to the full-throttle position 3. Turn the adjuster 2 in or out so that throt- tle valve bottom is positioned within the limits as specified.

  • Page 185: Chapter 6. Chassis

    CHAS FRONT WHEEL CHASSIS FRONT WHEEL TIRE AIR PRESSURE (COLD): 1 Wheel axle Maximum load- 90 kg (198 lb) 2 Speedometer gear unit except motorcycle* 3 Oil seal Cold tire pressure Front Rear 4 Bearing 100 kPa 100 kPa 5 Spacer Off-road riding* (1 kg/cm (1 kg/cm...

  • Page 186: Removal

    CHAS FRONT WHEEL REMOVAL WARNING Securely support the motorcycle so there is no danger of it falling over. 1.Place the motorcycle on a level place. 2.Elevate the front wheel by placing a suit- able stand under the frame and engine. 3.Loosen: Nuts (axle holder) 1 4.Remove:...
  • Page 187 CHAS FRONT WHEEL 4.Check: Spoke(s) Bend/damage → Replace. Loose spoke(s) → Retighten. Turn the wheel and tap the spokes with a screwdriver. NOTE: A tight spoke will emit a clear, ringing tone; a loose spoke will sound flat. 5.Tighten: Loose spokes Nipple: 2 Nm (0.2 m •...
  • Page 188 CHAS FRONT WHEEL 8.Check: Wheel bearings Abnormal noise/turn roughly/free play → Replace. Oil seals Wear/damage → Replace. ********************************* Oil seal and wheel bearing replacement steps: Clean the outside of the wheel hub. Remove the oil seal 1 using a flat-head screwdriver.

  • Page 189: Installation

    CHAS FRONT WHEEL INSTALLATION Reverse the “Removal” procedure. Note the following points. 1.Lubricate: Wheel axle Spacer 1 Bearings 2 Oil seal (lips) 3 Lithium soap base grease 2.Install: Collar NOTE: Install the oil seal taking care not to damage or reverse the lips. 3.Install: Speedometer gear unit NOTE:...

  • Page 190: Wheel Static Balance Adjustment

    CHAS FRONT WHEEL 6.Tighten: Nuts (axle holder) 1 Nuts 1: 10 Nm (1.0 m • kg, 7.2 ft • lb) CAUTION: The axle holder should be installed with the arrow mark 2 facing upward. WHEEL STATIC BALANCE ADJUSTMENT NOTE: After replacing the tire and/or rim, the wheel static balance should be adjusted.
  • Page 191 CHAS FRONT WHEEL 4.Adjust: Wheel static balance ********************************* Adjusting steps: Install a balancing weight 1 on the rim exactly opposite to the heavy spot “X”. NOTE: Start with the smallest weight. Turn the wheel so that the heavy spot is 90°...

  • Page 192: Rear Wheel

    CHAS REAR WHEEL REAR WHEEL 1 Rear wheel 0 Spacer TIRE AIR PRESSURE (COLD): 2 Cotter pin A Bearing Maximum load- 90 kg (198 lb) 3 Washer B Oil seal except motorcycle* 4 Chain puller 2 C Collar Cold tire pressure Front Rear 5 Collar...

  • Page 193: Removal

    CHAS REAR WHEEL REMOVAL 1.Place the motorcycle on a level place. WARNING Securely support the motorcycle so there is no danger of it falling over. 2.Elevate the rear wheel by placing a suit- able stand under the swingarm. 3.Remove: Cotter pin 1 Axle nut 2 Washer 3 Chain puller 1 4...

  • Page 194: Installation

    CHAS REAR WHEEL 2.Measure: Wheel runout Refer to “FRONT WHEEL”. 3.Check: Spoke(s) Wheel bearings Oil seals Refer to “FRONT WHEEL”. INSTALLATION Reverse the “Removal” procedure. Note the following points. 1.Lubricate: Rear wheel axle Bearings Oil seals Recommended lubricant: Lithium soap base grease 2.Install: Rear brake caliper assembly 3.Install:...

  • Page 195: Wheel Static Balance Adjustment

    CHAS REAR WHEEL 6.Install: Cotter pin 1 NOTE: Bend the ends of the cotter pin. WARNING Always use a new cotter pin. NB272004 WHEEL STATIC BALANCE ADJUSTMENT NOTE: After replacing the tire and/or rim, the wheel static balance should be adjusted. Adjust the wheel static balance with the brake disc and the wheel hub installed.

  • Page 196: Front And Rear Brake

    CHAS FRONT AND REAR BRAKE FRONT AND REAR BRAKE 1 Master cylinder assembly 9 Pad spring 2 Master cylinder cap 0 Bleed screw 3 Diaphragm A Brake pads 4 Master cylinder kit B Pad pin 5 Brake hose C Brake disc 6 Brake caliper assembly 7 Caliper piston assembly 8 Caliper seal kit...
  • Page 197 CHAS FRONT AND REAR BRAKE 1 Brake caliper assembly 0 Protector I Reservoir hose 2 Caliper piston assembly A Brake hose holder J Pin 3 Caliper seal kit B Brake hose K Cotter pin 4 Pad spring C Master cylinder assembly 5 Brake pads D Master cylinder kit 6 Shim...

  • Page 198: Brake Pad Replacement

    CHAS FRONT AND REAR BRAKE CAUTION: Disc brake components rarely require dis- assembly. DO NOT: Disassemble components unless abso- lutely necessary. Use solvents on internal brake compo- nent. Use contaminated brake fluid for clean- ing. Allow brake fluid to come in contact with the eyes otherwise eye injury may occur.
  • Page 199 CHAS FRONT AND REAR BRAKE 2.Remove: Bolts 1 Caliper body 2 3.Remove: Pad pins Brake pads 1 Pad spring 2 NOTE: Replace the pad spring if pad replacement is required. Replace the pads as a set if either is found to be worn to the wear limit.
  • Page 200 CHAS FRONT AND REAR BRAKE 7.Install: Pad spring 1 Brake pads 2 Pad pins Pad pins: 18 Nm (1.8 m • kg, 13 ft • lb) NOTE: Install the brake pad (inner) with its a por- tion aligning with b of the caliper. ********************************* Installation steps: Connect a clear plastic tube 1 tightly to...
  • Page 201 CHAS FRONT AND REAR BRAKE 10.Check: Brake lever operation A soft or spongy feeling → Bleed the brake system. Refer to “AIR BLEEDING (HYDRAULIC BRAKE SYSTEM)” in CHAPTER 3. Rear brake 1.Remove: Caliper protector Pad pins 1 2.Remove: Brake pads 1 Shim (piston side) 3.Measure: Pad thickness a...

  • Page 202: Caliper Disassembly

    CHAS FRONT AND REAR BRAKE ********************************* Installation steps: Connect a suitable hose 1 tightly to the caliper bleed screw. Then, place the other end of this hose into an open container. Loosen the caliper bleed screw and push the pistons into the caliper with your fin- ger.
  • Page 203 CHAS FRONT AND REAR BRAKE Front brake 1.Loosen: Pad pins 1 Union bolt 2 2.Remove: Caliper body Refer to “BRAKE PAD REPLACEMENT”. 3.Remove: Pad pins Union bolt Copper washers NOTE: Place a container under the caliper to col- lect any remaining brake fluid. 4.Remove: Brake pads Pad spring...
  • Page 204 CHAS FRONT AND REAR BRAKE WARNING Never try to pry out the piston. Cover the piston with a rag. Use care so that the piston does not cause injury as it is expelled from the cylinder. ********************************* 7.Remove: Piston seals 1 CAUTION: Remove the piston seal by pushing it in with a finger.

  • Page 205: Master Cylinder Disassembly

    CHAS FRONT AND REAR BRAKE 4.Remove: Union bolt Pad pins Brake pads (with pad shim) Pad spring Refer to “BRAKE PAD REPLACEMENT”. 5.Remove: Piston 1 ********************************* Removal steps: Blow compressed air into the hose joint opening to force out the caliper pistons from the caliper body.
  • Page 206 CHAS FRONT AND REAR BRAKE Front brake 1.Remove: Brush guard Brake lever Return spring (brake lever) Brake switch NOTE: Remove the brake switch by pushing up the stopper with a thin screwdriver. 2.Remove: Union bolt 1 Copper washers 2 NOTE: Place a container under the master cylinder to collect any remaining brake fluid.
  • Page 207 CHAS FRONT AND REAR BRAKE 2.Remove: Union bolt 1 Copper washers 2 3.Disconnect: Brake hoses 3 4.Remove: Master cylinder 1 5.Remove: Reservoir tank 1 6.Remove: Dust boot 1 Circlip 2 Push rod 3 Master cylinder kit 4 Joint (brake hose) 5 O-ring 6 7.Remove: Brake hose 1...

  • Page 208: Inspection And Repair

    CHAS FRONT AND REAR BRAKE INSPECTION AND REPAIR Recommended brake component replace- ment schedule: Brake pads As required Piston seals Every two years Brake hoses Every four years Replace only when brakes Brake fluid are disassembled. WARNING All internal parts should be cleaned in new brake fluid only.
  • Page 209 CHAS FRONT AND REAR BRAKE Å 3.Inspect: ı Master cylinder kits 1 Scratches/wear/damage → Replace as a set. Å Front ı Rear 4.Inspect: Reservoir tank 1 Cracks/damage → Replace. Diaphragm (front) 2 Diaphragm (rear) 3 Wear/damage → Replace. Å ı 5.Inspect: Brake hoses (front, rear) Cracks/wear/damage →...

  • Page 210: Caliper Assembly

    CHAS FRONT AND REAR BRAKE 8.Measure: Å ı Brake disc deflection Out of specification → Inspect wheel runout. If the wheel runout is within the limits replace the brake disc. Maximum deflection: 0.5 mm (0.020 in) 1 Dial gauge Brake disc thickness a Out of specification →...
  • Page 211 CHAS FRONT AND REAR BRAKE Front brake 1.Install: Piston seals 1 Pistons 2 2.Install: Support bracket 1 NOTE: Place the rubber boot securely in the groove of the guide pin when installing the caliper body. 3.Install: Pad spring 1 Brake pads 2 Pad pins 3 Refer to “BRAKE PAD REPLACEMENT”.
  • Page 212 CHAS FRONT AND REAR BRAKE 5.Fill: Brake fluid Recommended brake fluid: DOT #4 CAUTION: Brake fluid may erode painted surfaces or plastic parts. Always clean up spilled fluid immediately. WARNING Use only the designated quality brake fluid: otherwise, the rubber seals may deteriorate, causing leakage and poor brake performance.
  • Page 213 CHAS FRONT AND REAR BRAKE Rear brake 1.Install: Piston seals 1 Caliper piston 2 WARNING Always use new piston seals. 2.Install: Pad spring Brake pads (with pad shim) Pad pins Refer to “BRAKE PAD REPLACEMENT”. 3.Install: Caliper assembly 1 Copper washers 2 Union bolt 3 Rear wheel Refer to “REAR WHEEL”.
  • Page 214 CHAS FRONT AND REAR BRAKE 4.Fill: Brake fluid Recommended brake fluid: DOT #4 CAUTION: Brake fluid may erode painted surfaces or plastic parts. Always clean up spilled fluid immediately. WARNING Use only the designated quality brake fluid: otherwise, the rubber seals may deteriorate, causing leakage and poor brake performance.

  • Page 215: Master Cylinder Assembly

    CHAS FRONT AND REAR BRAKE MASTER CYLINDER ASSEMBLY WARNING All internal parts should be cleaned in new brake fluid only. Internal parts should be lubricated with brake fluid when installed. Brake fluid: DOT #4 Front brake 1.Install: Master cylinder kit 1 Circlip 2 Rubber boot 3 Plate 4...
  • Page 216 CHAS FRONT AND REAR BRAKE NOTE: Install the brake hose as shown. WARNING Proper hose routing is essential to insure safe motorcycle operation. Refer to “CABLE ROUTING” in CHAPTER Always use new copper washers. 4.Install: Brake switch Spring Brake lever Brake lever cover Mirror (right) NOTE:...
  • Page 217 CHAS FRONT AND REAR BRAKE WARNING Proper hose routing is essential to insure safe motorcycle operation. Refer “CABLE ROUTING” in CHAPTER 2. Always use new copper washers. 3.Install: Pin 1 Washer 2 Cotter pin 3 WARNING Always use a new cotter pin. 4.Install: Reservoir tank NOTE:...
  • Page 218 CHAS FRONT AND REAR BRAKE 7.Air bleed: Brake system Refer to “AIR BLEEDING (HYDRAULIC BRAKE SYSTEM)” in CHAPTER 3. 8.Inspect: Brake fluid level Fluid level is under the “LOWER” level line → Replenish. Refer to “BRAKE FLUID LEVEL INSPEC- TION” in CHAPTER 3. 9.Install: Diaphragm 1 Holder (diaphragm) 2...

  • Page 219: Front Fork

    CHAS FRONT FORK FRONT FORK 1 Front fork assembly (left) B Piston metal M Axle holder 2 Cap bolt C Retaining clip N Boot 3 Upper seat D Dust seal 4 Collar E Oil seal 5 Lower seat F Plain washer 6 Fork spring G Slide metal 7 Locknut...

  • Page 220: Removal

    CHAS FRONT FORK REMOVAL WARNING Support the motorcycle securely so there is no danger of it falling over. 1.Place the motorcycle on a level place. 2.Elevate the front wheel by placing a suit- able stand under the frame and engine. 3.Remove: Front wheel Refer to “FRONT WHEEL”.

  • Page 221: Disassembly

    CHAS FRONT FORK DISASSEMBLY 1.Remove: Cap bolt (from the inner tube) 2.Remove: Cap bolt 1 (from the piston rod) NOTE: Remove the cap bolt using the rod holder Rod holder: P/N. YM-01434 3.Remove: Collars 1 Spring seats 2 Fork spring 3 4.Drain: Fork oil 5.Remove:...

  • Page 222: Inspection

    CHAS FRONT FORK 7.Remove: Inner fork tube ********************************* Removal steps: Hold the fork leg horizontally. Clamp the caliper mounting boss of the outer fork tube securely in a vise with soft jaws. Separate the inner tube from the outer tube by pulling forcefully but carefully on the inner tube.
  • Page 223 CHAS FRONT FORK 2.Measure: Fork spring free length a Out of specification → Replace. Fork spring free length: 472 mm (18.58 in) Minimum free length: 462 mm (18.19 in) 3.Inspect: Damper rod 1 Wear/bends/damage → Replace. Contamination → Blow out all oil pas- sages with compressed air.

  • Page 224: Assembly

    CHAS FRONT FORK ASSEMBLY Reverse the “DISASSEMBLY” procedure. Note the following points. NOTE: When assembling the front fork, be sure to replace the following parts. Piston metal Slide metal Oil seal Dust seal Make sure all components are clean before assembling the fork. 1.Install: Rebound spring 1 Piston rod 2...
  • Page 225 CHAS FRONT FORK 4.Tighten: Base valve 1 (damper rod) Use the damper rod holder 2 to hold the damper rod. Damper rod holder: YM-01418 Base valve (damper rod): 55 Nm (5.5 m • kg, 40 ft • lb) ® LOCTITE WARNING Always use a new copper washer.
  • Page 226 Fork oil capacity: 555 cm (19.57 Imp oz, 18.76 US oz) Recommended oil: Yamaha suspension oil 01 or equivalent CAUTION: Be sure to use the recommended fork oil. If other oils are used, they may have an adverse effect on the front fork perfor- mance.
  • Page 227 CHAS FRONT FORK 10.After filling, pump the inner tube slowly up and down (about 150 mm (5.90 in)) to distribute the fork oil once more. NOTE: Be careful not to stroke the inner tube over. A stroke of 150 mm (5.90 in) or more will cause air to enter.

  • Page 228: Installation

    CHAS FRONT FORK ********************************* Installing steps: Install the rod puller 1 and attachment 2 to the damper rod 3. Rod puller: P/N. YM-01437 Rod puller attachment: P/N. 90890-01436 Install the fork spring, spring seats and collars. Pull up the rod puller and set the rod holder 1 between the locknut 2 and spring seat.
  • Page 229 CHAS FRONT FORK NOTE: Position the inner fork tube end in such a way that it is flush a with the top of the handle crown. 2.Tighten: Pinch bolts 1 (lower bracket) Pinch bolts 2 (handlebar crown) Cap bolt 3 Pinch bolt 1 (lower bracket): 30 Nm (3.0 m •...

  • Page 230: Steering Head And Handlebar

    CHAS STEERING HEAD AND HANDLEBAR STEERING HEAD AND HANDLEBAR 1 Handlebar holder (upper) 9 Ring nut G Stay 2 Handlebar holder (lower) 0 Damper collar 3 Headlight stay 2 A Washer 4 Cap B Cover 5 Handlebar crown C Washer 6 Headlight stay 1 D Bearing (upper) 7 Brake hose holder...
  • Page 231 CHAS STEERING HEAD AND HANDLEBAR 1 Handlebar grip (right) 7 Throttle cable holder (rear) C Brush guard (left) 2 Leaf ring 8 Boot D Brush guard (right) 3 Throttle guide tube 9 Throttle cable 1 4 Handlebar 0 Throttle cable 2 5 Handlebar grip (left) A Clutch cable 6 Throttle cable holder (front)

  • Page 232: Removal

    CHAS STEERING HEAD AND HANDLEBAR REMOVAL Handlebar WARNING Securely support the motorcycle so there is no danger of it falling over. 1.Place the motorcycle on a level place. 2.Remove: Master cylinder assembly 1 Master cylinder bracket 2 Bands 3 3.Remove: Handlebar switch (right) 4.Remove: Throttle cable holder 1...
  • Page 233 CHAS STEERING HEAD AND HANDLEBAR 6.Remove: Handlebar upper holder 1 Handlebar 2 Handlebar lower holder 3 Steering head WARNING Securely support the motorcycle so there is no danger of it falling over. 1.Place the motorcycle on a level place. 2.Elevate the front wheel by placing a suit- able stand under the frame and engine.
  • Page 234 CHAS STEERING HEAD AND HANDLEBAR 9.Remove: Speedometer assembly 1 10.Remove: Handlebar crown 1 NOTE: Loosen the steering stem nut 2 and remove the handlebar crown 1. Take care that the handlebar crown does not touch the fuel tank. 11.Remove: Lock washer 1 Ring nut 2 Rubber washer NOTE:...

  • Page 235: Inspection

    CHAS STEERING HEAD AND HANDLEBAR INSPECTION 1.Inspect: Handlebar 1 Bends/cracks/damage → Replace. WARNING Do not attempt to straighten a bent han- dlebar as this may dangerously weaken the handlebar. ********************************* Replacement steps: Remove the handlebar grip. Apply a light coat of an adhesive for rub- ber on the left new handlebar end.

  • Page 236: Installation

    CHAS STEERING HEAD AND HANDLEBAR CAUTION: Always replace bearings and races as a set. A slant installation of the bearings and the races will damage the frame, so take care to install them horizontally. Do not strike the rollers. 3.Inspect: Handlebar crown 1 Lower bracket 2 Cracks/damage →...
  • Page 237 CHAS STEERING HEAD AND HANDLEBAR 2.Install: Handlebar holder 1 (lower) Clip Handlebar 2 Bolt (handlebar): 23 Nm (2.3 m • kg, 17 ft • lb) NOTE: The upper handlebar holder should be installed with the punch mark 1 facing forward. 2 Forward CAUTION: First tighten the bolts on the front side of...
  • Page 238 CHAS STEERING HEAD AND HANDLEBAR NOTE: When installing handlebar switch (right), make sure its projection fits into the hole. Install the master cylinder bracket with the “UP” mark facing upward. Tighten first the upper bolt, then the lower bolt. Bolt (master cylinder bracket): 7 Nm (0.7 m •...
  • Page 239 CHAS STEERING HEAD AND HANDLEBAR 3.Tighten: Ring nut 1 ********************************* Tightening steps: Tighten the ring nut using the ring nut wrench 2. Ring nut wrench: P/N. YU-33975 NOTE: Set the torque wrench to the ring nut wrench so that they form a right angle. Ring nut 1 (lower) (initial tightening): 5 Nm (0.5 m •...
  • Page 240 CHAS STEERING HEAD AND HANDLEBAR 5.Install: Handlebar crown 1 NOTE: Temporarily tighten the steering stem nut 6.Install: Brake hose holder Front flasher assembly 7.Install: Front fork Refer to “FRONT FORK”. NOTE: Temporarily tighten the pinch bolts. 8.Tighten: Steering stem nut Steering stem nut: 120 Nm (12 m •...
  • Page 241 CHAS STEERING HEAD AND HANDLEBAR WARNING Proper hose routing is essential to insure safe motorcycle operation. Refer “CABLE ROUTING” in CHAPTER 2. 11.Connect: Speedometer cable Refer to “CABLE ROUTING” in CHAPTER 12.Install: Headlight assembly Front cover 13.Install: Brake caliper Holder (brake hose) Refer to “FRONT FORK”.

  • Page 242: Rear Shock Absorber And Swingarm

    CHAS REAR SHOCK ABSORBER AND SWINGARM REAR SHOCK ABSORBER AND SWINGARM 1 Rear shock absorber 6 - 58...
  • Page 243 CHAS REAR SHOCK ABSORBER AND SWINGARM 1 Pivot shaft B Collar 2 Thrust cover (swingarm) C Dust seal 3 Oil seal D Circlip 4 Bearing E Bearing 5 Swingarm F Bearing 6 Bush G Oil seal 7 Oil seal H Collar 8 Bearing I Oil seal 9 Connecting rod...

  • Page 244: Handling Notes

    CHAS REAR SHOCK ABSORBER AND SWINGARM HANDLING NOTES WARNING This shock absorber contains highly pres- surized nitrogen gas. Read and understand the following information before handling the shock absorber. The manufacturer can- not be held responsible for property dam- age or personal injury that may result from improper handling.

  • Page 245: Removal

    CHAS REAR SHOCK ABSORBER AND SWINGARM REMOVAL Air filter case WARNING Securely support the motorcycle so there is no danger of it falling over. 1.Place the motorcycle on a level place. 2.Remove: Side covers Seat Fuel tank Refer to “SEAT, FUEL TANK AND COV- ERS”...
  • Page 246 CHAS REAR SHOCK ABSORBER AND SWINGARM 9.Remove: Air filter case assembly Rear shock absorber WARNING Securely support the motorcycle so there is no danger of it falling over. 1.Place the motorcycle on a level place. 2.Remove: Side covers Seat Fuel tank Refer to “SEAT, FUEL TANK AND COV- ERS”...
  • Page 247 CHAS REAR SHOCK ABSORBER AND SWINGARM 7.Remove: Rear shock absorber bolt (lower) 8.Remove: Rear shock absorber nut 1 (upper) 9.Remove: Rear shock absorber Swingarm WARNING Securely support the motorcycle so there is no danger of it falling over. 1.Place the motorcycle on a level place. 2.Elevate the rear wheel by placing a suit- able stand under the frame and engine.
  • Page 248 CHAS REAR SHOCK ABSORBER AND SWINGARM 5.Remove: Brake hose holders 1 Rear brake caliper 6.Remove: Chain case 1 Chain guide 2 NOTE: When removing the chain case, lift up and remove the chain case from the swingarm L-shaped part 3 on the back. 7.Check: Swingarm free play *********************************...
  • Page 249 CHAS REAR SHOCK ABSORBER AND SWINGARM 8.Remove: Bolt (relay arm-connecting rod) 9.Remove: Nut 1 (pivot shaft) Washer 2 Pivot shaft 3 Swingarm 10.Remove: Relay arm 11.Remove: Caps Connecting arm 1 12.Remove: Chain protector 1 6 - 65...

  • Page 250: Inspection

    CHAS REAR SHOCK ABSORBER AND SWINGARM INSPECTION 1.Inspect: Rear shock absorber Oil leaks/damage → Replace the rear shock absorber. Gas cylinder Oil leaks/damage → Replace the rear shock absorber. WARNING Do not disassemble the shock absorber, because of the highly pressurized nitrogen gas in it.
  • Page 251 CHAS REAR SHOCK ABSORBER AND SWINGARM Features Water seepage is no longer a problem since the polylube is solid. If water seeps into the bearing, it will emulsify and will not flow out. Lubrication can continuously be supplied to the contact points when heat is gener- ated by the friction caused by the centrifu- gal forces, since the lubricant is solid and always remains inside the bearing.

  • Page 252: Installation

    CHAS REAR SHOCK ABSORBER AND SWINGARM 6.Inspect: Oil seal 1 Wear/damage → Replace. Washer 2 Thrust cover 3 Bush 4 Scratches/damage → Replace. 7.Inspect: Chain guide 1 Chain protector 2 Cracks/damage → Replace. INSTALLATION Rear shock absorber Reverse the “REMOVAL” procedure. Note the following points.
  • Page 253 CHAS REAR SHOCK ABSORBER AND SWINGARM 6.Install: Air filter case Refer to “REAR SHOCK ABSORBER AND SWINGARM”. 7.Install: CDI unit Rear frame 2 Swingarm Reverse “REMOVAL” procedure. Note the following points. 1.Lubricate: Oil seal Bushing Thrust cover (inside) Collar Pivot shaft Bolt (relay arm-swingarm) Bolt (connecting arm-relay arm) Bolt (connecting arm-frame)
  • Page 254 CHAS REAR SHOCK ABSORBER AND SWINGARM 5.Tighten: Swingarm Nut 1 (pivot shaft) Nut 1 (pivot shaft): 105 Nm (10.5 m • kg, 75 ft • lb) 6.Install: Nut 1 (connecting arm-relay arm) Nut 1 (connecting arm-relay arm): 59 Nm (5.9 m • kg, 43 ft • lb) 7.Tighten: Bolt 1 (chain case) Bolt 2 (chain guide)
  • Page 255 CHAS REAR SHOCK ABSORBER AND SWINGARM 11.Tighten: Axle nut Axle nut: 105 Nm (10.5 m • kg, 75 ft • lb) Refer to “REAR WHEEL”. 12.Install: Cotter pin 1 NOTE: Bend the ends of the cotter pin as illus- trated. WARNING Always use a new cotter pin.

  • Page 256: Drive Chain And Sprockets

    CHAS DRIVE CHAIN AND SPROCKETS DRIVE CHAIN AND SPROCKETS 1 Driven sprocket 2 Chain joint 3 Drive chain 4 Washer 5 Drive sprocket 6 - 72...

  • Page 257: Removal

    CHAS DRIVE CHAIN AND SPROCKETS NOTE: Before removing the drive chain and sprockets, drive chain slack and 10-link length of drive chain should be measured. REMOVAL 1.Elevate the rear wheel by placing a suit- able stand under the frame and engine. WARNING Securely support the motorcycle so there is no danger of it falling over.

  • Page 258: Inspection

    CHAS DRIVE CHAIN AND SPROCKETS 5.Remove: Chain joint Use the drive chain cutter tool 1. Drive chain cutter: P/N. 90890-01286 6.Remove: Link plate 1 O-ring 2 Pin 3 Drive chain 4 7.Remove: Rear wheel Refer to “REAR WHEEL”. INSPECTION 1.Measure: 10-link length a (drive chain) Use a vernier caliper gauge.

  • Page 259: Installation

    CHAS DRIVE CHAIN AND SPROCKETS CAUTION: This motorcycle has a drive chain with small rubber O-rings 1 between the chain plates. Steam cleaning, high-pressure washers, and certain solvents can damage these O-rings. Use only kerosene to clean the drive chain. 3.Inspect: O-ring 1 (drive chain) Damage →...
  • Page 260 CHAS DRIVE CHAIN AND SPROCKETS 2.Install: Rear wheel Refer to “REAR WHEEL”. 3.Install: Drive chain 1 Drive sprocket 2 Washer 3 Nut 4 Nut (drive sprocket): 110 Nm (11.0 m • kg, 80 ft • lb) NOTE: Tighten the nut (drive sprocket) while applying the rear brake.
  • Page 261 CHAS DRIVE CHAIN AND SPROCKETS CAUTION: Too little chain slack will overload the engine and other vital parts; keep the slack within the specified limits. 7.Tighten: Axle nut Bolt (drive sprocket) Axle nut: 105 Nm (10.5 m • kg, 75 ft • lb) Refer to “REAR WHEEL”.

  • Page 262: Chapter 7. Electrical

    – ELEC TTR250L(C) CIRCUIT DIAGRAM ELECTRICAL TTR250L(C) CIRCUIT DIAGRAM 7 - 1...
  • Page 263 – ELEC TTR250L(C) CIRCUIT DIAGRAM 1 AC magneto I “LIGHTS” switch 2 Rectifier/regulator J Headlight 3 Main switch 4 Fuse (main) 5 Battery 6 Starter relay 7 Starter motor 8 Diode 9 CDI unit 0 Ignition coil A Spark plug B “ENGINE STOP”...

  • Page 264: Electrical Components

    – ELEC ELECTRICAL COMPONENTS ELECTRICAL COMPONENTS 1 Wireharness BATTERY: 2 Rectifier/regulator SPECIFIC GRAVITY: 1.320 3 CDI unit 4 Battery IGNITION COIL: 5 Fuse PRIMARY COIL RESISTANCE: 0.36 ~ 0.48 Ω at 20 °C (68 °F) 6 Fuse holder assembly 7 Ignition coil SECONDARY COIL RESISTANCE: 8 Plug cap 5.4 ~ 7.4 kΩ...
  • Page 265 – ELEC ELECTRICAL COMPONENTS 1 Neutral switch 2 Starter relay 7 - 4...

  • Page 266: Checking Of Connections

    – ELEC CHECKING OF CONNECTIONS CHECKING OF CONNECTIONS Dealing with stains, rust, moisture, etc. on the connector. 1.Disconnect: Connector 2.Dry each terminal with an air blower. 3.Connect and disconnect the connector two or three times. 4.Pull the lead to check that it will not come off.

  • Page 267: Ignition System

    – ELEC IGNITION SYSTEM IGNITION SYSTEM CIRCUIT DIAGRAM 1 AC magneto B “ENGINE STOP” switch 3 Main switch 4 Fuse (main) 5 Battery 9 CDI unit 0 Ignition coil A Spark plug 7 - 6...
  • Page 268 – ELEC IGNITION SYSTEM NB283000 TROUBLESHOOTING IF THE IGNITION SYSTEM SHOULD BECOME INOPERATIVE (NO SPARK OR INTERMITTENT SPARK) NB283100 Procedure Check: 1.Fuse (main) 7.Main switch 2.Battery 8.“ENGINE STOP” switch 3.Spark plug 9.Pickup coil resistance 4.Ignition spark gap 10.Wiring connection (entire ignition system) 5.Spark plug cap resistance 6.Ignition coil resistance NB283110...
  • Page 269 – ELEC IGNITION SYSTEM C0NTINUITY EB283140 3.Spark plug Check the spark plug condition. Check the spark plug type. Check the spark plug gap. Refer to “SPARK PLUG INSPECTION” in CHAPTER 3. INCORRECT Standard spark plug: CR9E (NGK), U27ESR-N (N.D.) Spark plug gap: Repair or replace the spark plug.
  • Page 270 – ELEC IGNITION SYSTEM OUT OF SPECIFICATION Check the spark plug cap for specified resistance. Spark plug cap resistance: 10 kΩ at 20 °C (68 °F) Replace the spark plug cap. MEET SPECIFICATION NB283170 6.Ignition coil resistance Disconnect the ignition coil leads from the ignition coil.
  • Page 271 – ELEC IGNITION SYSTEM C0NTINUITY NB283180 7.Main switch Disconnect the main switch coupler from the wireharness. Check the switch component for conti- nuity between “Red 1 and Brown 2”. INCORRECT Replace the main switch. CORRECT NB283190 8.“ENGINE STOP” switch Disconnect the handlebar switch (right) coupler from the wireharness.
  • Page 272 – ELEC IGNITION SYSTEM C0NTINUITY 9.Pickup coil resistance Disconnect the pickup coil coupler from the wireharness. Connect the pocket tester (Ω × 100) to the pickup coil terminal. Tester (+) lead → White/Red 1 Tester (–) lead → White/Blue 2 Check the pickup coil for specified resis- OUT OF SPECIFICATION tance.

  • Page 273: Electrical Starting System

    – ELEC ELECTRICAL STARTING SYSTEM ELECTRICAL STARTING SYSTEM CIRCUIT DIAGRAM 3 Main switch C “START” switch 4 Fuse (main) F Neutral switch 5 Battery G Clutch switch 6 Starter relay 7 Starter motor 8 Diode B “ENGINE STOP” switch 7 - 12...

  • Page 274: Starting Circuit Operation

    – ELEC ELECTRICAL STARTING SYSTEM NB284001 STARTING CIRCUIT OPERATION The starting circuit on this model consist of the starter motor and starter relay. If the “ENGINE STOP” switch and the main switch are both closed, the starter motor can operate only if: The transmission is in neutral (the neutral switch is closed).
  • Page 275 – ELEC ELECTRICAL STARTING SYSTEM NB284100 TROUBLESHOOTING STARTER MOTOR DOES NOT OPERATE. NB284110 Procedure Check: 7.Neutral switch 1.Fuse (main) 8.Clutch switch 2.Battery 9.“START” switch 3.Starter motor 10.Wiring connection 4.Starter relay (entire electric starting system) 5.Main switch 6.“ENGINE STOP” switch NB284120 NOTE: Remove the following parts before trouble- Pocket tester:...
  • Page 276 – ELEC ELECTRICAL STARTING SYSTEM C0NTINUITY NB284150 WARNING 3.Starter motor A wire for jumper lead must have the Connect the battery positive terminal 1 equivalent capacity as that of the battery and starter motor cable 2 using a lead or more, otherwise it may cause the jumper lead 3*.
  • Page 277 – ELEC ELECTRICAL STARTING SYSTEM C0NTINUITY NB284170 5.Main switch Disconnect the main switch coupler from the wireharness. Check the switch component for conti- nuity between “Red 1 and Brown 2”. INCORRECT Replace the main switch. CORRECT NB284190 6.“ENGINE STOP” switch Disconnect the handlebar switch (right) coupler from the wireharness.
  • Page 278 – ELEC ELECTRICAL STARTING SYSTEM C0NTINUITY NB284200 7.Neutral switch Disconnect the neutral switch lead from the wireharness. Check the switch component for conti- nuity between “Sky blue Ground”. INCORRECT Replace the neutral switch. CORRECT 8.Clutch switch Disconnect the clutch switch coupler from the wireharness.
  • Page 279 – ELEC ELECTRICAL STARTING SYSTEM C0NTINUITY NB284230 9.“START” switch Disconnect the handlebar switch (right) coupler from the wireharness. Check the “START” switch component for continuity between “Blue/White 1 and Black 2”. INCORRECT Replace the handlebar switch (right). CORRECT POOR CONNECTION 10.Wiring connection Check the entire starting system for con- nections.

  • Page 280: Starter Motor

    – ELEC ELECTRICAL STARTING SYSTEM STARTER MOTOR 1 Starter motor lead 2 Brush 3 Bracket 4 O-ring 5 Armature 6 Yoke 7 - 19...
  • Page 281 – ELEC ELECTRICAL STARTING SYSTEM NB284250 Removal 1.Remove: Starter motor Refer to “ENGINE DISASSEMBLY” in CHAPTER 4. NB284251 Disassembly 1.Put identifying marks 1 on the brackets for reassembly as shown. 2.Remove: Bolts 2 3.Remove: Armature 1 Yoke 2 Brush 3 NB284252 Inspection and repair 1.Inspect:...
  • Page 282 – ELEC ELECTRICAL STARTING SYSTEM NOTE: The mica insulation of the commutator must be undercut to ensure proper opera- tion of the commutator. 4.Inspect: Armature coil (insulation/continuity) Defects → Replace the starter motor. ********************************** Inspecting steps: Connect the pocket tester for continuity check 1 and insulation check 2.
  • Page 283 – ELEC ELECTRICAL STARTING SYSTEM 2.Install: Brush set NOTE: Align the projection on the brush seat with the slot on the housing. 3.Install: Armature 1 Bracket 2 NOTE: When installing the armature, avoid dam- age to the brush. 4.Install: Yoke 1 O-ring 2 NOTE: Align the match mark A and install.

  • Page 284: Charging System

    – ELEC CHARGING SYSTEM CHARGING SYSTEM CIRCUIT DIAGRAM 1 A.C. magneto 2 Rectifier/regulator 4 Fuse (main) 5 Battery 7 - 23...
  • Page 285 – ELEC CHARGING SYSTEM NB285000 TROUBLESHOOTING THE BATTERY IS NOT CHARGED. NB285100 Procedure Check: 1.Fuse (main) 4.Stator coil resistance 2.Battery 5.Wiring connection 3.Charging voltage (entire charging system) NB285110 NOTE: Inductive tachometer: Remove the following parts before trou- YU-8036-A bleshooting. Pocket tester: 1)Seat YU-03112 2)Side covers...
  • Page 286 – ELEC CHARGING SYSTEM Start the engine and accelerate to about 3,000 r/min. Check the charging voltage. MEETS SPECIFICATION Charging voltage: 13.0 ~ 15.0 V at 3,000 r/min. NOTE: Use a fully charged battery. Charging circuit is good. OUT OF SPECIFICATION NB285150 Tester (+) lead →...

  • Page 287: Lighting System

    – ELEC LIGHTING SYSTEM LIGHTING SYSTEM CIRCUIT DIAGRAM 3 Main switch 4 Fuse (main) 5 Battery H Tail light I “LIGHTS” switch J Headlight 7 - 26...
  • Page 288 – ELEC LIGHTING SYSTEM NB286000 TROUBLESHOOTING HEADLIGHT, “HIGH BEAM” INDICATOR LIGHT, AND/OR TAILLIGHT DO NOT COME ON NB286100 Procedure Check; 1.Fuse (main) 4.“LIGHTS” switch 2.Battery 5.Wiring connection 3.Main switch (entire charging system) NB286110 NOTE: Pocket tester: Remove the following parts before trou- YU-03112 ble shooting.
  • Page 289 – ELEC LIGHTING SYSTEM INCORRECT Replace the main switch. CORRECT 4.“LIGHTS” switch Disconnect the “LIGHTS” switch coupler from the wireharness. Check the switch component for conti- nuity between “Brown 1 and Yellow 2”. INCORRECT Replace the handlebar switch (right). CORRECT NB286160 POOR CONNECTION 5.Wiring connection...

  • Page 290: Lighting System Check

    – ELEC LIGHTING SYSTEM NB286170 LIGHTING SYSTEM CHECK 1.The headlight and “HIGH BEAM” indica- tor light do not come on. NO CONTINUITY 1.Bulb and bulb socket Check the bulb and bulb socket for conti- nuity. Replace the bulb and/or bulb socket. CONTINUITY NB286180 2.Voltage...
  • Page 291 – ELEC LIGHTING SYSTEM 2.Taillight does not come on. NO CONTINUITY 1.Bulb and bulb socket Check the bulb and bulb socket for conti- nuity. Replace the bulb and/or bulb socket. CONTINUITY NB286220 2.Voltage Connect the pocket tester (DC 20 V) to the bulb socket connector.

  • Page 292: Shtg

    TRBL STARTING FAILURE/HARD STARTING SHTG NB291000 TROUBLESHOOTING NOTE: The following troubleshooting does not cover all the possible causes of trouble. It should be helpful, however, as a guide to troubleshooting. Refer to the relative procedure in this man- ual for inspection, adjustment and replacement of parts. NB291100 STARTING FAILURE/HARD STARTING FUEL SYSTEM...

  • Page 293: Poor Idle Speed Performance

    TRBL STARTING FAILURE/HARD STARTING/POOR IDLE SPEED PERFORMANCE/POOR MEDIUM AND HIGH SPEED PERFORMANCE SHTG Switches and wiring Valve and camshaft Faulty main switch Improperly sealed valve Faulty “ENGINE STOP” switch Improper valve to valve seat contact Broken or shorted wiring Improper valve timing Faulty neutral switch Broken valve spring Faulty “START”...

  • Page 294: Faulty Gear Shifting

    FAULTY GEAR SHIFTING/ TRBL CLUTCH SLIPPING/DRAGGING SHTG NB293100 FAULTY GEAR SHIFTING HARD SHIFTING Refer to “CLUTCH DRAGGING”. NB293120 SHIFT PEDAL DOES NOT MOVE Shift shaft Transmission Bent shift shaft Seized transmission gear Jammed impurities Incorrectly assembled transmission Shift cam, shift fork Groove jammed with impurities Seized shift fork Bent shift fork guide bar...

  • Page 295: Overheating

    OVERHEATING/FAULTY BRAKE/FRONT FORK OIL TRBL LEAKAGE AND FRONT FORK MALFUNCTION SHTG NB295100 OVERHEATING OVERHEATING Ignition system Fuel system Improper spark plug gap Improper carburetor main jet Improper spark plug heat range (improper setting) Faulty ignition coil Improperly adjusted fuel level Clogged air filter element Compression system Engine oil...

  • Page 296: Instable Handling

    TRBL INSTABLE HANDLING SHTG INSTABLE HANDLING INSTABLE HANDLING Handlebars Steering Improperly installed or bent Improperly installed upper bracket Bent steering stem Tires Improperly installed steering stem Uneven tire pressures on both sides (improperly tightened ring nut) Incorrect tire pressure Damaged bearing or bearing race Unevenly worn tires Front forks Wheels...

  • Page 297: Faulty Signal And Lighting System

    TRBL FAULTY SIGNAL AND LIGHTING SYSTEM SHTG NB299100 FAULTY SIGNAL AND LIGHTING SYSTEM HEADLIGHT DARK BULB BURNT OUT Improper bulb Improper bulb Too many electric accessories Faulty battery Hard charging (broken stator coil and/or Faulty rectifier/regulator faulty rectifier/regulator) Improperly grounded Incorrect connection Faulty main and/or “LIGHTS”...

  • Page 298: Ttr250L(C) Wiring Diagram

    TTR250L(C) WIRING DIAGRAM 1 AC magneto 2 Rectifier/regulator 3 Main switch 4 Fuse (main) 5 Battery 6 Starter relay 7 Starter motor 8 Diode W/L O 9 CDI unit 0 Ignition coil (BLACK) A Spark plug B “ENGINE STOP” switch C “START”...
  • Page 299 YAMAHA MOTOR CO., LTD. 2500 SHINGAI IWATA SHIZUOKA JAPAN PRINTED IN U.S.A.

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