Yamaha YFM660RN Service Manual
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Yamaha YFM660RN Service Manual

Yamaha YFM660RN Service Manual

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YFM660RN
YFM660RNC
SERVICEMANUAL
LIT-11616-14-21
5LP-28197-E0

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Summary of Contents for Yamaha YFM660RN

  • Page 1 YFM660RN YFM660RNC SERVICEMANUAL LIT-11616-14-21 5LP-28197-E0...

  • Page 2: Specifications

    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 maintenance and repairs on Yamaha machine has a basic understanding of the mechanical ideas and the procedures of machine repair.

  • Page 3: How To Use This Manual

    EB002000 HOW TO USE THIS MANUAL MANUAL ORGANIZATION This manual consists of chapters for the main categories of subjects. (See “Illustrated symbols”) 1st title 1: This is the title of the chapter with its symbol in the upper right corner of each page. 2nd title 2: This title indicates the section of the chapter and only appears on the first page of each section.

  • Page 4: Periodic Checks And Adjustments

    EB003000 ILLUSTRATED SYMBOLS Illustrated symbols 1 to 9 are printed on the SPEC top right of each page and indicate the subject INFO of each chapter. 1 General information 2 Specifications 3 Periodic checks and adjustments CHAS 4 Chassis 5 Engine 6 Cooling system 7 Carburetion 8 Electrical...

  • Page 5: Table Of Contents

    TABLE OF CONTENTS GENERAL INFORMATION INFO SPECIFICATIONS SPEC PERIODIC CHECKS AND ADJUSTMENTS CHASSIS CHAS ENGINE COOLING SYSTEM COOL CARBURETION CARB – ELECTRICAL ELEC TROUBLESHOOTING TRBL SHTG...
  • Page 6 CHAPTER 1. GENERAL INFORMATION MACHINE IDENTIFICATION ................ 1-1 VEHICLE IDENTIFICATION NUMBER ..........1-1 MODEL LABEL ..................1-1 IMPORTANT INFORMATION ............... 1-2 PREPARATION FOR REMOVAL PROCEDURES ....... 1-2 REPLACEMENT PARTS ............... 1-2 GASKETS, OIL SEALS AND O-RINGS ..........1-2 LOCK WASHERS/PLATES AND COTTER PINS ......... 1-3 BEARINGS AND OIL SEALS ..............
  • Page 7 CHAPTER 3. PERIODIC CHECKS AND ADJUSTMENTS INTRODUCTION ................... 3-1 INFO PERIODIC MAINTENANCE/LUBRICATION INTERVALS ......3-1 SEAT, FENDERS AND FUEL TANK ............3-3 SEAT, FRONT PANEL, FOOTREST GUARDS AND ENGINE SKID PLATE ............... 3-3 SPEC HEADLIGHTS AND FRONT FENDER ..........3-4 REAR FENDER ..................
  • Page 8 CHECKING THE TIRE ................ 3-47 CHECKING THE WHEEL ..............3-49 CHECKING AND LUBRICATING THE CABLE ........3-49 LUBRICATING THE LEVERS AND PEDAL ........3-50 ELECTRICAL ....................3-51 CHECKING THE BATTERY ..............3-51 CHECKING THE FUSE ............... 3-56 ADJUSTING THE HEADLIGHT BEAM ..........3-58 REPLACING THE HEADLIGHT BULB ..........
  • Page 9 CHECKING THE FRONT AND REAR BRAKE CALIPER ....4-34 ASSEMBLING THE FRONT BRAKE CALIPER ........4-35 ASSEMBLING THE REAR BRAKE CALIPER ........4-36 INSTALLING THE FRONT BRAKE CALIPER ........4-37 INSTALLING THE REAR BRAKE CALIPER ........4-38 STEERING SYSTEM .................. 4-40 INFO HANDLEBAR ..................
  • Page 10 CHAPTER 5. ENGINE ENGINE REMOVAL ..................5-1 MUFFLER AND EXHAUST PIPES ............5-1 LEFT FOOTREST ................. 5-2 LEADS, CABLES AND HOSES ............5-3 ENGINE MOUNTING BOLTS ............... 5-5 INSTALLING THE ENGINE ..............5-7 CYLINDER HEAD COVER ................5-8 REMOVING THE CYLINDER HEAD COVER ........5-10 CHECKING THE CYLINDER HEAD COVER ........
  • Page 11 CLUTCH ...................... 5-43 REMOVING THE CLUTCH ..............5-47 REMOVING THE PRIMARY DRIVE GEAR AND BALANCER DRIVEN GEAR ........... 5-47 CHECKING THE FRICTION PLATE ........... 5-48 CHECKING THE CLUTCH PLATE ............. 5-48 CHECKING THE CLUTCH SPRING ........... 5-49 CHECKING THE CLUTCH HOUSING ..........5-49 INFO CHECKING THE CLUTCH BOSS ............
  • Page 12 TRANSMISSION ..................5-72 MAIN AXLE ..................5-74 DRIVE AXLE ..................5-75 CHECKING THE SHIFT FORK ............5-77 CHECKING THE SHIFT DRUM ............5-77 CHECKING THE TRANSMISSION ............. 5-77 ASSEMBLING THE MAIN AXLE AND DRIVE AXLE ......5-78 INSTALLING THE TRANSMISSION ........... 5-79 CHAPTER 6.

  • Page 13: Electrical

    CHAPTER 8. ELECTRICAL ELECTRICAL COMPONENTS ..............8-1 INFO CHECKING THE SWITCH ................8-2 CHECKING THE SWITCH ..............8-2 CHECKING A SWITCH SHOWN IN THE MANUAL ......8-2 CHECKING THE SWITCH CONTINUITY ..........8-3 SPEC IGNITION SYSTEM ..................8-5 CIRCUIT DIAGRAM ................8-5 TROUBLESHOOTING ................

  • Page 14: Troubleshooting

    CHAPTER 9. TROUBLESHOOTING STARTING FAILURE/HARD STARTING ............. 9-1 FUEL SYSTEM ..................9-1 ELECTRICAL SYSTEM ................. 9-1 COMPRESSION SYSTEM ..............9-2 POOR IDLE SPEED PERFORMANCE ............9-2 POOR IDLE SPEED PERFORMANCE ..........9-2 POOR MEDIUM AND HIGH-SPEED PERFORMANCE ....... 9-2 POOR MEDIUM AND HIGH-SPEED PERFORMANCE ....... 9-2 FAULTY GEAR SHIFTING ................

  • Page 15: Gen Info

    MACHINE IDENTIFICATION INFO GENERAL INFORMATION MACHINE IDENTIFICATION VEHICLE IDENTIFICATION NUMBER The vehicle identification number 1 is stamped into the left side of the frame. MODEL LABEL The model label 1 is affixed to the air filter case cover. This information will be needed to order spare parts.

  • Page 16: Important Information

    5.Keep all parts away from any source of fire. EB101010 REPLACEMENT PARTS 1.Use only genuine Yamaha parts for all replacements. Use oil and grease recom- mended by Yamaha for all lubrication jobs. Other brands may be similar in function and appearance, but inferior in quality.

  • Page 17: Lock Washers/Plates And Cotter Pins

    IMPORTANT INFORMATION INFO EB101030 LOCK WASHERS/PLATES AND COTTER PINS 1.Replace all lock washers/plates 1 and cotter pins after removal. Bend lock tabs along the bolt or nut flats after the bolt or nut has been tightened to specification. EB101040 BEARINGS AND OIL SEALS 1.Install bearings and oil seals so that the manufacturer’s marks or numbers are visible.

  • Page 18: Checking Of Connections

    CHECKING OF CONNECTIONS INFO EB801000 CHECKING OF CONNECTIONS Check the connectors for stains, rust, mois- ture, etc. 1.Disconnect: Connector 2.Check: Connector Moisture → Dry each terminal with an air blower. Stains/rust → Connect and disconnect the terminals several times. 3.Check: Connector leads Looseness →...

  • Page 19: Special Tools

    SPECIAL TOOLS INFO EB102001 SPECIAL TOOLS The following special tools are necessary for complete and accurate tune-up and assembly. Use only the appropriate special tools; this will help prevent damage caused by the use of inappropriate tools or improvised techniques. Special tools may differ by shape and part number from country to country.
  • Page 20 SPECIAL TOOLS INFO Tool No. Tool name/How to use Illustration Piston pin puller 90890-01304 YU-01304 This tool is used to remove the piston pin. Tappet adjusting tool (3 mm) 90890-01311 YM-08035 This tool is necessary for adjusting the valve clearance. Fuel level gauge 90890-01312 YM-01312-A...
  • Page 21 SPECIAL TOOLS INFO Tool No. Tool name/How to use Illustration Oil filter wrench 90890-01469 YM-01469 This tool is needed to loosen or tighten the oil filter cartridge. Ball joint remover/installer set 90890-01474 YM-01474 These tools are used to removing or installing the ball joint.
  • Page 22 90890-06754 This instrument is necessary for checking the ignition system components. Dynamic spark tester YM-34487 This instrument is necessary for checking the ignition system components. Yamaha bond No. 1215 ® Sealant (Quick Gasket Bond 90890-85505 Sealant ACC-11001-05-01 This sealant (bond) is used on crankcase mating surfaces, etc.

  • Page 23: Chapter 2. Specifications

    SPEC GENERAL SPECIFICATIONS SPECIFICATIONS GENERAL SPECIFICATIONS Item Standard Model code: 5LP1 : (Except for California) 5LP3 : (For California) Dimensions: Overall length 1,830 mm (72.0 in) Overall width 1,100 mm (43.3 in) Overall height 1,150 mm (45.3 in) Seat height 860 mm (33.9 in) Wheelbase 1,245 mm (49.0 in)
  • Page 24 SPEC GENERAL SPECIFICATIONS Item Standard Carburetor: Type/quantity BSR33/2 Manufacturer MIKUNI Spark plug: Type/manufacturer DPR8EA-9/NGK Spark plug gap 0.8 ~ 0.9 mm (0.031 ~ 0.035 in) Clutch type: Wet, multiple disc Transmission: Primary reduction system Spur gear Primary reduction ratio 71/34 (2.088) Secondary reduction system Chain drive Secondary reduction ratio...
  • Page 25 SPEC GENERAL SPECIFICATIONS Item Standard Tire pressure (cold tire): Maximum load* 100 kg (220 lb) Off-road riding front 27.5 kPa (0.275 kg/cm , 4.0 psi) rear 27.5 kPa (0.275 kg/cm , 4.0 psi) *Load in total weight of cargo, rider and acces- sories Brake: Front brake...

  • Page 26: Spec

    SPEC MAINTENANCE SPECIFICATIONS MAINTENANCE SPECIFICATIONS ENGINE Item Standard Limit Cylinder head: Warp limit ---- 0.05 mm (0.002 in) Cylinder: Bore size 100.005 ~ 100.045 mm 100.1 mm (3.9372 ~ 3.9388 in) (3.94 in) Measuring point 50 mm (2.0 in) ---- Camshaft: Drive method Chain drive (Left)
  • Page 27 SPEC MAINTENANCE SPECIFICATIONS Item Standard Limit Camshaft runout limit ---- 0.03 mm (0.0012 in) Timing chain: Timing chain type/No. of links 75-RH2015/126 ---- Timing chain adjustment method Automatic ---- Rocker arm/rocker arm shaft: Shaft outside diameter 11.976 ~ 11.991 mm ---- (0.4715 ~ 0.4721 in) Arm-to-shaft clearance...
  • Page 28 SPEC MAINTENANCE SPECIFICATIONS Item Standard Limit Stem-to-guide clearance 0.010 ~ 0.037 mm 0.08 mm (0.0004 ~ 0.0015 in) (0.0031 in) 0.025 ~ 0.052 mm 0.10 mm (0.0010 ~ 0.0020 in) (0.0039 in) Stem runout limit ---- 0.01 mm (0.0004 in) Valve seat width 0.9 ~ 1.1 mm 1.6 mm...
  • Page 29 SPEC MAINTENANCE SPECIFICATIONS Item Standard Limit Piston: Piston to cylinder clearance 0.05 ~ 0.07 mm 0.15 mm (0.0020 ~ 0.0028 in) (0.0059 in) Piston size “D” 99.945 ~ 99.995 mm ---- (3.9348 ~ 3.9368 in) Measuring point “H” 2.5 mm (0.10 in) ---- Piston off-set 1.0 mm (0.04 in)
  • Page 30 SPEC MAINTENANCE SPECIFICATIONS Item Standard Limit Crankshaft: Crank width “A” 74.95 ~ 75.00 mm ---- (2.9508 ~ 2.9528 in) Runout limit C1 ---- 0.03 mm (0.0012 in) ---- 0.03 mm (0.0012 in) Big end side clearance “D” 0.32 ~ 0.64 mm 1.0 mm (0.0126 ~ 0.0252 in) (0.0394 in)
  • Page 31 SPEC MAINTENANCE SPECIFICATIONS Item Standard Limit Transmission: Main axle deflection limit ---- 0.08 mm (0.0031 in) Drive axle deflection limit ---- 0.08 mm (0.0031 in) Shifter: Shifter type Shift drum and guide bar ---- Decompression device: Device type Auto decomp ---- Air filter oil grade: Engine oil...
  • Page 32 SPEC MAINTENANCE SPECIFICATIONS Item Standard Limit Cooling system: Radiator core Width 219 mm (8.62 in) ---- Height 300 mm (11.8 in) ---- Depth 16 mm (0.63 in) ---- Radiator cap opening pressure 95 ~ 125 kPa (0.95 ~ 1.25 kg/cm ---- 13.8 ~ 18.1 psi) Radiator capacity...
  • Page 33 SPEC MAINTENANCE SPECIFICATIONS Item Standard Limit Cylinder head tightening sequence: 2 - 11...
  • Page 34 SPEC MAINTENANCE SPECIFICATIONS Tightening torques Tightening torque Part Thread Part to be tightened Q’ty Remarks name size m·kg ft·lb Cylinder head (exhaust pipe) Stud bolt Cylinder head Bolt Bolt Bolt Spark plug — Cylinder head cover Bolt Camshaft end cap Bolt Oil check bolt —...
  • Page 35 SPEC MAINTENANCE SPECIFICATIONS Tightening torque Part Thread Part to be tightened Q’ty Remarks name size m·kg ft·lb Bearing retainer Screw AC magneto rotor 15.0 Starter clutch Bolt Balancer driven gear 14.0 Use a lock washer. Primary drive gear 15.0 Use a lock washer.

  • Page 36: Chassis

    SPEC MAINTENANCE SPECIFICATIONS CHASSIS Item Standard Limit Steering system: Steering bearing type Ball and race bearing ---- Front suspension: Shock absorber travel 110 mm (4.33 in) ---- Fork spring free length 316.5 mm (12.46 in) ---- Spring fitting length 293.5 mm (11.56 in) ---- Spring rate (K1)
  • Page 37 SPEC MAINTENANCE SPECIFICATIONS Item Standard Limit Front disc brake: Type Dual ---- Disc outside diameter × thickness 161.0 × 3.5 mm (6.34 × 0.14 in) ---- Pad thickness inner 4.2 mm (0.17 in) 1 mm (0.04 in) Pad thickness outer 4.2 mm (0.17 in) 1 mm (0.04 in)
  • Page 38 SPEC MAINTENANCE SPECIFICATIONS Tightening torques Tightening torque Part to be tightened Thread size Remarks m·kg ft·lb Engine bracket (upper) and frame Engine bracket (upper) and engine Engine bracket (lower) and frame Engine bracket (lower) and engine Engine bracket (middle and lower) and engine Swingarm pivot shaft, engine and frame Rear shock absorber and frame Relay arm and swingarm...
  • Page 39 SPEC MAINTENANCE SPECIFICATIONS Tightening torque Part to be tightened Thread size Remarks m·kg ft·lb Front brake master cylinder and brake lever Front brake master cylinder and brake hose Brake hose joint and frame Bleed screw Front brake pad holding bolt Front brake caliper and brake hose Front brake caliper retaining bolt Rear axle ring nut...

  • Page 40: Electrical

    Rotor rotation direction detection coil resis- ---- tance/color Red – White/Blue C.D.I. unit model/manufacturer F8T37971/MITSUBISHI ---- Ignition coil: Model/manufacturer 2JN/YAMAHA ---- Minimum spark gap 6 mm (0.24 in) ---- 0.18 ~ 0.28 Ω at 20 °C (68 °F) Primary winding resistance ---- Secondary winding resistance 6.32 ~ 9.48 kΩ...
  • Page 41 SPEC MAINTENANCE SPECIFICATIONS Item Standard Limit Starter relay Model/manufacturer MS5F-721/JIDECO ---- Amperage rating 180 A ---- 4.18 ~ 4.62 Ω at 20 °C (68 °F) Coil winding resistance ---- Thermostat switch: Thermostat switch 1 Model/manufacturer 5GH/NIPPON THERMOSTAT ---- Thermostat switch 2 Model/manufacturer 5LP/NIPPON THERMOSTAT ----...

  • Page 42: How To Use The Conversion Table

    HOW TO USE THE CONVERSION TABLE/ SPEC GENERAL TORQUE SPECIFICATIONS EB201000 EB202001 HOW TO USE THE CONVERSION GENERAL TORQUE TABLE SPECIFICATIONS All specification data in this manual are listed This chart specifies torque for standard fasten- in SI and METRIC UNITS. ers with standard I.S.O.

  • Page 43: Lubrication Points And Lubricant Types

    Shift fork/guide bar Shift drum/shift shaft/shift cam stopper ball Shift lever/shift guide  Sealant (Quick Gasket Crankcase mating surfaces Yamaha bond No.1215  Sealant (Quick Gasket Cylinder head and cylinder head cover mating surfaces Yamaha bond No.1215  AC magneto lead grommet...

  • Page 44: Coolant Flow Diagrams

    SPEC COOLANT FLOW DIAGRAMS COOLANT FLOW DIAGRAMS 1 Radiator 9 Radiator inlet hose 2 Radiator fan 0 Thermo switch 2 3 Radiator outlet hose A Thermo switch 1 4 Water pump inlet hose 5 Water pump 6 Water jacket outlet pipe 7 Thermostat inlet hose 8 Thermostat 2 - 22...

  • Page 45: Oil Flow Diagrams

    SPEC OIL FLOW DIAGRAMS OIL FLOW DIAGRAMS 1 Oil tank 2 Oil pipe 2 3 Oil pipe 1 2 - 23...
  • Page 46 SPEC OIL FLOW DIAGRAMS 1 Oil delivery pipe 2 2 Oil delivery pipe 1 3 Oil filter 4 Crankshaft 5 Oil pump 2 - 24...
  • Page 47 SPEC OIL FLOW DIAGRAMS 1 Oil pipe 2 2 Drive axle 3 Main axle 4 Engine oil drain bolt (engine) 5 Oil pipe 1 6 Oil strainer 7 Shift drum 2 - 25...
  • Page 48 SPEC OIL FLOW DIAGRAMS 1 Oil delivery pipe 2 2 Oil filter cartridge 3 Oil pump rotor 1 4 Oil pump rotor 2 5 Oil pipe 1 6 Main axle 2 - 26...

  • Page 49: Cable Routing

    SPEC CABLE ROUTING CABLE ROUTING 1 Parking brake cable È Fasten the handlebar switch lead, park switch 2 Starter cable lead and clutch switch lead to the handlebar with 3 Clutch cable the plastic band. 4 Throttle cable É Fasten the front brake switch lead to the handle- 5 Front brake hose bar with the plastic band.
  • Page 50 SPEC CABLE ROUTING 1 Front brake hose B Brake pipe 2 Throttle cable C Headlight lead coupler (right) 3 Main switch lead D Radiator fan breather hose 4 Indicator light lead E Headlight lead (right) 5 Clutch cable 6 Parking brake cable È...
  • Page 51 SPEC CABLE ROUTING 1 Throttle cable È Put the wire harness and coolant reservoir hose 2 Fuel tank breather hose with the plastic holder. 3 Fuel hose É Fasten the wire harness, AC magneto lead, 4 Carburetor air vent hose speed sensor lead, negative battery lead and 5 Negative battery lead rear brake switch lead with the plastic band.
  • Page 52 SPEC CABLE ROUTING 1 Coolant reservoir hose È Pass the negative battery lead between the wire 2 Carburetor air vent hose harness and frame. 3 Reservoir tank breather hose 4 Rectifier/regulator 5 CDI unit 6 Negative battery lead 7 AC magneto lead 8 Wire harness 9 Starter motor lead 0 Tail/brake light lead...
  • Page 53 SPEC CABLE ROUTING 1 Radiator fan breather hose È Fasten the reverse control cable to the frame 2 Reverse control cable with the plastic band. 3 Parking brake cable É 15 ~ 25 mm (0.59 ~ 0.98 in) 4 Clutch cable 2 - 31...
  • Page 54 SPEC CABLE ROUTING 1 Rear brake hose 2 Parking brake cable 3 Negative battery lead 4 AC magneto lead 5 Crankcase breather hose 6 Carburetor drain hose 7 Rear brake switch 8 Speed sensor 9 Speed sensor lead 0 Rear brake switch lead 2 - 32...
  • Page 55 SPEC CABLE ROUTING 1 Thermo switch 1 lead È Fasten the fan motor lead, headlight lead (right) 2 Headlight lead (right) and thermo switch 1 lead to the frame with the 3 Radiator fan breather hose plastic band. 4 Thermo switch 2 lead 5 Carburetor breather hose 6 Headlight lead (left) 7 Wire harness...
  • Page 56 SPEC CABLE ROUTING 1 Positive battery lead È Fasten the wire harness with the plastic clamp. 2 Tail/brake light lead É Fasten the starter motor lead and starter relay 3 Coolant reservoir breather hose lead with the plastic clamp. 4 Negative battery lead 5 Coolant reservoir hose 6 Starter motor lead 7 Wire harness...

  • Page 57: Chk Adj

    • Lubricate every 6 months.** Fittings and fasten- • Check all chassis fittings and fasteners. ers* • Correct if necessary. It is recommended that these items be serviced by a Yamaha dealer. ** Lithium soap base grease 3 - 1...
  • Page 58 PERIODIC MAINTENANCE/LUBRICATION INTERVALS NOTE: Recommended brake fluid: DOT 4 Brake fluid replacement: 1.When disassembling the master cylinder or caliper cylinder, replace the brake fluid. Normally check the brake fluid level and add fluid as required. 2.On the inner parts of the master cylinder and caliper cylinder, replace the oil seals every two years.

  • Page 59: Seat, Fenders And Fuel Tank

    SEAT, FENDERS AND FUEL TANK SEAT, FENDERS AND FUEL TANK SEAT, FRONT PANEL, FOOTREST GUARDS AND ENGINE SKID PLATE Order Job name/Part name Q’ty Remarks Removing the seat, front panel, foot- Remove the parts in the order below. rest guard and engine skid plate Seat NOTE: Pull back the seat lock lever, than pull up...

  • Page 60: Headlights And Front Fender

    SEAT, FENDERS AND FUEL TANK HEADLIGHTS AND FRONT FENDER Order Job name/Part name Q’ty Remarks Removing the headlight and front Remove the parts in the order below. fender Seat and front panel Refer to “SEAT, FRONT PANEL, FOOT- REST GUARDS AND ENGINE SKID PLATE”.

  • Page 61: Rear Fender

    SEAT, FENDERS AND FUEL TANK REAR FENDER Order Job name/Part name Q’ty Remarks Removing the rear fender Remove the parts in the order below. Seat Refer to “SEAT, FRONT PANEL, FOOT- REST GUARDS AND ENGINE SKID PLATE”. Front fender Refer to “HEADLIGHTS AND FRONT FENDER”.

  • Page 62: Fuel Tank

    SEAT, FENDERS AND FUEL TANK FUEL TANK Order Job name/Part name Q’ty Remarks Removing the fuel tank Remove the parts in the order below. Seat and front panel Refer to “SEAT, FRONT PANEL, FOOT- REST GUARDS AND ENGINE SKID PLATE”. Front fender Refer to “HEADLIGHTS AND FRONT FENDER”.
  • Page 63 SEAT, FENDERS AND FUEL TANK Order Job name/Part name Q’ty Remarks Rubber cover 1 Rubber cover 2 Hose holder For installation, reverse the removal pro- cedure. 3 - 7...

  • Page 64: Engine

    ADJUSTING THE VALVE CLEARANCE ENGINE ADJUSTING THE VALVE CLEARANCE NOTE: The valve clearance must be adjusted when the engine is cool to the touch. Adjust the valve clearance when the piston is at the Top Dead Center (T.D.C.) on the com- pression stroke.
  • Page 65 ADJUSTING THE VALVE CLEARANCE 6.Check: Valve clearance Out of specification → Adjust. Valve clearance (cold): Intake: 0.10 ~ 0.15 mm (0.0039 ~ 0.0059 in) Exhaust: 0.15 ~ 0.20 mm (0.0059 ~ 0.0079 in) *********************************************** Checking steps: Turn the crankshaft counterclockwise with a wrench.
  • Page 66 ADJUSTING THE VALVE CLEARANCE 7.Adjust: Valve clearance *********************************************** Adjustment steps: Loosen the locknut 1. Insert a feeler gauge 2 between the adjuster end and the valve end. Turn the adjuster 3 clockwise or counter- clockwise with the tappet adjusting tool 4 until the proper clearance is obtained.

  • Page 67: Adjusting The Timing Chain

    ADJUSTING THE VALVE CLEARANCE/ADJUSTING THE TIMING CHAIN/ADJUSTING THE IDLING SPEED 10.Install: Fuel tank Front fender Seat Refer to “SEAT, FENDERS AND FUEL TANK”. ADJUSTING THE TIMING CHAIN Adjustment free. ADJUSTING THE IDLING SPEED 1.Start the engine and let it warm up for sev- eral minutes.

  • Page 68: Adjusting The Throttle Lever Free Play

    ADJUSTING THE IDLING SPEED/ ADJUSTING THE THROTTLE LEVER FREE PLAY 4.Adjust: Engine idling speed *********************************************** Adjustment steps: Turn the throttle stop screw 1 in or out until the specified idling speed is obtained. Idling speed becomes Turning in higher. Idling speed becomes Turning out lower.
  • Page 69 ADJUSTING THE THROTTLE LEVER FREE PLAY 2.Adjust: Throttle lever free play *********************************************** Adjustment steps: First step: Pull back the adjuster cover 1. Loosen the locknut 2 on the carburetor side. Turn the adjuster 3 in or out until the correct free play is obtained.

  • Page 70: Adjusting The Speed Limiter

    ADJUSTING THE SPEED LIMITER ADJUSTING THE SPEED LIMITER The speed limiter keeps the carburetor throttle from becoming fully-opened even when the throttle lever is applied to the maximum posi- tion. Screwing in the adjuster stops the engine speed from increasing. 1.Check: Speed limiter length a Out of specification →...

  • Page 71: Adjusting The Starter Cable

    ADJUSTING THE STARTER CABLE ADJUSTING THE STARTER CABLE 1.Adjust: Starter cable *********************************************** Adjustment steps: Disconnect the starter cable 1 from the car- buretor body. NOTE: Do not remove the starter plunger 2 from the starter cable. Measure the starter plunger stroke distance a of the starter lever 3 fully close-to-fully open position.

  • Page 72: Checking The Spark Plug

    CHECKING THE SPARK PLUG CHECKING THE SPARK PLUG 1.Remove: Spark plug 2.Check: Spark plug type Incorrect → Replace. Standard spark plug: DPR8EA-9/NGK 3.Check: Electrode 1 Wear/damage → Replace. Insulator 2 Abnormal color → Replace. Normal color is a medium-to-light tan color. 4.Clean the spark plug with a spark plug cleaner or wire brush.

  • Page 73: Checking The Ignition Timing

    CHECKING THE IGNITION TIMING CHECKING THE IGNITION TIMING NOTE: Engine idling speed and throttle cable free play should be adjusted properly before checking the ignition timing. 1.Attach: Tachometer Timing light (to spark plug lead) Timing light: P/N. YM-33277-A, 90890-03141 2.Check: Ignition timing *********************************************** Checking steps:...

  • Page 74: Measuring The Compression Pressure

    MEASURING THE COMPRESSION PRESSURE MEASURING THE COMPRESSION PRESSURE NOTE: Insufficient compression pressure will result in a loss of performance. 1.Check: Valve clearance Out of specification → Adjust. Refer to “ADJUSTING THE VALVE CLEAR- ANCE”. 2.Start the engine and let it warm up for sev- eral minutes.

  • Page 75: Checking The Engine Oil Level

    MEASURING THE COMPRESSION PRESSURE/ CHECKING THE ENGINE OIL LEVEL Compression pressure (at sea level): Standard: 1,250 kPa (12.5 kg/cm , 181 psi) Minimum: 1,050 kPa (10.5 kg/cm , 149 psi) Maximum: 1,350 kPa (13.5 kg/cm , 192 psi) *********************************************** Measurement steps: Crank over the engine with the electric starter (be sure the battery is fully charged) with the throttle fully-open until the compres-...

  • Page 76: Changing The Engine Oil

    CHECKING THE ENGINE OIL LEVEL/ CHANGING THE ENGINE OIL 3.Check: Engine oil level Oil level should be between the minimum level mark a and the maximum level mark Low oil level → Add oil to the proper level. NOTE: Wait a few minutes until the oil settles before inspecting the oil level.
  • Page 77 CHANGING THE ENGINE OIL 4.Remove: Dipstick 1 Engine oil drain bolt (oil tank) 2 Engine oil drain bolt (crankcase) 3 Drain the engine oil from the oil tank and crankcase. 5.If the oil filter cartridge is also to be replaced, perform the following procedure.
  • Page 78 CHANGING THE ENGINE OIL Tighten the new oil filter cartridge to specifi- cation with an oil filter wrench. Oil filter cartridge: 17 Nm (1.7 m • kg, 12 ft • lb) *********************************************** 6.Install: Engine oil drain bolt (crankcase) 30 Nm (3.0 m • kg, 22 ft • lb) Engine oil drain bolt (oil tank) 25 Nm (2.5 m •...

  • Page 79: Adjusting The Clutch Cable

    CHANGING THE ENGINE OIL/ ADJUSTING THE CLUTCH CABLE 11.Check: Engine oil pressure *********************************************** Slightly loosen the oil gallery bolt 1. Start the engine and keep it idling until engine oil starts to seep from the oil gallery bolt. If no engine oil comes out after one minute, turn the engine off so that it will not seize.

  • Page 80: Cleaning The Air Filter

    ADJUSTING THE CLUTCH CABLE/ CLEANING THE AIR FILTER 2.Adjust: Clutch lever free play *********************************************** Adjustment steps: Pull the rubber cover 1 off. Loosen the locknut 2 and finger tighten the adjusting bolt 3. Loosen the locknut 4. Turn the adjusting nut 5 until the clutch lever free play is within the specified limits.
  • Page 81 CLEANING THE AIR FILTER 4.Remove: Air filter element assembly 1 Air filter element cap 2 Air filter element 3 NOTE: When removing the air filter element, rotate the air filter element cap 1/4 of a turn and remove the element. CAUTION: Never operate the engine with the air filter element removed.
  • Page 82 CLEANING THE AIR FILTER CAUTION: Do not twist or wring out the element. This could damage the foam material. Apply engine oil to the element. Squeeze out the excess oil. NOTE: The element should be wet but not dripping. *********************************************** 7.Install: Air filter element Air filter case cover...

  • Page 83: Checking The Coolant Level

    CHECKING THE COOLANT LEVEL/ CHANGING THE COOLANT CHECKING THE COOLANT LEVEL 1.Place the machine on a level surface. 2.Check: Coolant level The coolant level should be between the minimum level mark a and maximum level mark b. Below the minimum level mark → Add the recommended coolant to the proper level.
  • Page 84 CHANGING THE COOLANT 4.Drain: Coolant (from the coolant reservoir) 5.Connect: Coolant reservoir hose 6.Remove: Radiator cap 1 WARNING A hot radiator is under pressure. Therefore, do not remove the radiator cap when the engine is hot. Scalding hot fluid and steam may be blown out, which could cause seri- ous injury.
  • Page 85 CHANGING THE COOLANT 11.Fill: Cooling system (with the specified amount of the recom- mended coolant) Recommended antifreeze: High-quality ethylene glycol antifreeze containing corrosion inhibitors for aluminum engines Mixing ratio: 1:1 (antifreeze:water) Quantity: Total amount: 1.3 L (1.14 lmp qt, 1.37 US qt) Coolant reservoir capacity: 0.29 L (0.26 lmp qt, 0.31 US qt)
  • Page 86 CHANGING THE COOLANT 13.Fill: Coolant reservoir (with the recommended coolant to the proper level) 14.Install: Coolant reservoir cap 15.Start the engine, warm it up for several min- utes, and then turn it off. 16.Check: Coolant level Refer to “CHECKING THE COOLANT LEVEL”.

  • Page 87: Checking The Coolant Temperature Warning Light

    CHECKING THE COOLANT TEMPERATURE WARNING LIGHT/CLEANING THE SPARK ARRESTER CHECKING THE COOLANT TEMPERATURE WARNING LIGHT 1 Coolant temperature warning light CLEANING THE SPARK ARRESTER 1.Clean: Spark arrester *********************************************** Cleaning steps: WARNING Select a well-ventilated area free of com- bustible materials. Always let the exhaust system cool before performing this operation.

  • Page 88: Cleaning The Spark Arrester

    CLEANING THE SPARK ARRESTER Tap the tailpipe lightly with a soft-face ham- mer or suitable tool, then use a wire brush to remove any carbon deposits from the spark arrester portion of the tailpipe and the inner contact surfaces of the muffler. Insert the tailpipe into the muffler and align the bolt holes.

  • Page 89: Chassis

    ADJUSTING THE FRONT BRAKE/ ADJUSTING THE REAR BRAKE CHASSIS ADJUSTING THE FRONT BRAKE 1.Check: Brake lever free play a Out of specification → Bleed the front brake system. Refer to “AIR BLEEDING (HYDRAULIC BRAKE SYSTEM)”. Brake lever free play (at the brake lever end): 0 mm (0 in) ADJUSTING THE REAR BRAKE...

  • Page 90: Adjusting The Parking Brake

    ADJUSTING THE REAR BRAKE/ ADJUSTING THE PARKING BRAKE WARNING After this adjustment is performed, lift the rear wheels off the ground by placing a block under the engine, and spin the rear wheels to ensure there is no brake drag. If any brake drag is noticed perform the above steps again.

  • Page 91: Checking The Brake Fluid Level

    ADJUSTING THE PARKING BRAKE/ CHECKING THE BRAKE FLUID LEVEL WARNING After this adjustment is performed, lift the rear wheels off the ground by placing a block under the engine, and spin the rear wheels to ensure there is no brake drag. If any brake drag is noticed perform the above steps again.

  • Page 92: Checking The Front Brake Pad

    CHECKING THE FRONT BRAKE PAD/ CHECKING THE REAR BRAKE PAD/ ADJUSTING THE REAR BRAKE LIGHT SWITCH CHECKING THE FRONT BRAKE PAD 1.Remove: Front wheels 2.Check: Brake pad Wear indicators 1 almost in contact with the brake disc → Replace the brake pads as a set.

  • Page 93: Checking The Brake Hose

    ADJUSTING THE REAR BRAKE LIGHT SWITCH/ CHECKING THE BRAKE HOSE 1.Check: Rear brake light operation timing Incorrect → Adjust. 2.Adjust: Rear brake light operation timing *********************************************** Hold the main body 1 of the rear brake light switch so that it does not rotate and turn the adjusting nut 2 in direction a or b until the rear brake light comes on at the proper time.

  • Page 94: Bleeding The Hydraulic Brake System

    CHECKING THE BRAKE HOSE/ BLEEDING THE HYDRAULIC BRAKE SYSTEM 6.Install: Front fender Seat Refer to “SEAT, FENDERS AND FUEL TANK”. BLEEDING THE HYDRAULIC BRAKE SYSTEM WARNING Bleed the brake system if: The system has been disassembled. A brake hose or brake pipe have been loosened or removed.

  • Page 95: Adjusting The Shift Pedal

    BLEEDING THE HYDRAULIC BRAKE SYSTEM/ ADJUSTING THE SHIFT PEDAL j. Tighten the bleed screw. Bleed screw: 6 Nm (0.6 m • kg, 4.3 ft • lb) NOTE: If bleeding is difficult, it may be necessary to let the brake fluid settle for a few hours. Repeat the bleeding procedure when the tiny bubbles in the system have disappeared.

  • Page 96: Adjusting The Reverse Control Cable

    ADJUSTING THE REVERSE CONTROL CABLE/ ADJUSTING THE DRIVE CHAIN SLACK ADJUSTING THE REVERSE CONTROL CABLE 1.Check: Reverse knob free play a Out of specification → Adjust. Reverse knob free play: 0 mm (0 in) 2.Adjust: *********************************************** Adjustment steps: Pull the boots 1 and 2 off. Loosen the locknut 3.
  • Page 97 ADJUSTING THE DRIVE CHAIN SLACK 3.Measure: Drive chain slack a Out of specification → Adjust. Drive chain slack: 30 ~ 45 mm (1.18 ~ 1.77 in) 4.Adjust: Drive chain slack *********************************************** Adjustment steps: Loosen the hub nuts 1. Loosen the locknuts 2. Turn both adjusting bolts 3 in direction a or b until the specified drive chain slack is obtained.

  • Page 98: Checking The Steering System

    CHECKING THE STEERING SYSTEM/ ADJUSTING THE TOE-IN CHECKING THE STEERING SYSTEM 1.Place the machine on a level surface. 2.Check: Steering assembly bushings Move the handlebar up and down, and/or back and forth. Excessive play → Replace the steering stem bushings. 3.Check: Tie-rod ends Turn the handlebar to the left and/or right...
  • Page 99 ADJUSTING THE TOE-IN *********************************************** Toe-in measurement steps: NOTE: Before measuring the toe-in, make sure that the tire pressure is correct. Mark both front tire tread centers. Raise the front end of the machine so that there is no weight on the front tires. Face the handlebar straight ahead.

  • Page 100: Adjusting The Front Shock Absorber

    ADJUSTING THE TOE-IN/ ADJUSTING THE FRONT SHOCK ABSORBER *********************************************** Adjustment steps: Mark both tie-rods ends. This reference point will be needed during adjustment. Loosen the locknuts (tie-rod end) 1 of both tie-rods. The same number of turns should be given to both the right and left tie-rods 2 until the specified toe-in is obtained.

  • Page 101: Adjusting The Rear Shock Absorber

    ADJUSTING THE REAR SHOCK ABSORBER ADJUSTING THE REAR SHOCK ABSORBER 1.Adjust: Spring preload *********************************************** Adjustment steps: Elevate the rear wheels by placing a suitable stand under the frame. Loosen the locknut 1. Turn the adjusting ring 2 in direction a or Spring preload is Direction a increased (suspension...
  • Page 102 ADJUSTING THE REAR SHOCK ABSORBER 2.Adjust: Rebound damping force *********************************************** Adjustment steps: Turn the adjusting screw 1 in direction a or Rebound damping force Direction a is increased. Rebound damping force Direction b is decreased. From the fully turned-in position: Standard: 10 clicks out Minimum: 20 clicks out Maximum: 3 clicks out...

  • Page 103: Checking The Tire

    TIRE CHARACTERISTICS 1)Tire characteristics influence the handling of ATV’s. The tires listed below have been approved by Yamaha Motor Co., Ltd. for this model. If other tire combinations are used, they can adversely affect your machine’s handling characteristics and are therefore not recommended.
  • Page 104 CHECKING THE TIRE MAXIMUM LOADING LIMIT 1)Vehicle load limit (total weight of cargo, rider and accessories, and tongue weight): 100 kg (220 lb) 1.Measure: Tire pressure (cold tire pressure) Out of specification → Adjust. NOTE: The low-pressure tire gauge 1 is included as standard equipment.

  • Page 105: Checking The Wheel

    CHECKING THE TIRE/CHECKING THE WHEEL/ CHECKING AND LUBRICATING THE CABLE 2.Check: Tire surfaces Wear/damage → Replace. Tire wear limit a: Front and rear: 3.0 mm (0.12 in) WARNING It is dangerous to ride with a worn-out tire. When tire wear is out of specification, replace the tire immediately.

  • Page 106: Lubricating The Levers And Pedal

    Cable sheath Damage → Replace. 2.Check: Cable operation Unsmooth operation → Lubricate or replace. Recommended lubricant: Yamaha chain and cable lube or Engine oil NOTE: Hold the cable end up and apply several drops of lubricant to the cable. 3.Apply:...

  • Page 107: Electrical

    CHECKING THE BATTERY EB305000 ELECTRICAL CHECKING THE BATTERY NOTE: Since the MF battery is a sealed type battery, it is not possible to measure the specific gravity of the electrolyte in order to check the charge state of the battery. Therefore the charge of the battery has to be checked by measuring the voltage at the battery terminals.
  • Page 108 CHECKING THE BATTERY Batteries generate explosive hydrogen gas. Always follow these preventive measures: Charge batteries in a well-ventilated area. Keep batteries away from fire, sparks or open flames (e.g., welding equipment, lighted cigarettes, etc.). DO NOT SMOKE when charging or han- dling batteries.
  • Page 109 CHECKING THE BATTERY Check the condition of the battery using the following charts. Example: Open-circuit voltage = 12.0 V Charging time = 6.5 hours Charge condition of the battery = 20 ~ 30% Charging method for MF batteries CAUTION: If it is impossible to set the standard charging current, be careful not to over- charge.
  • Page 110 CHECKING THE BATTERY Charging method using a variable voltage charger 3 - 54...
  • Page 111 CHECKING THE BATTERY Charging method using a constant voltage charger 3 - 55...
  • Page 112 CHECKING THE BATTERY/CHECKING THE FUSE 5.Check: Battery terminals Dirty → Clean with a wire brush. Poor connection → Correct. NOTE: After cleaning the terminals, apply a light coat of grease. 6.Install: Battery 7.Connect: Battery leads CAUTION: First, connect the positive lead 1, then connect the negative lead 2.

  • Page 113: Checking The Fuse

    CHECKING THE FUSE NOTE: Set the tester to the “Ω × 1” position. Pocket tester: P/N. YU-03112, 90890-03112 If the tester indicates 0, replace the fuse. *********************************************** 3.Replace: Blown fuse *********************************************** Replacement steps: Turn off the ignition. Install a new fuse of the proper amperage. Turn on switches to verify operation of the related electrical devices.

  • Page 114: Adjusting The Headlight Beam

    ADJUSTING THE HEADLIGHT BEAM/ REPLACING THE HEADLIGHT BULB ADJUSTING THE HEADLIGHT BEAM 1.Adjust: Headlight beam (vertically) *********************************************** Adjustment steps: Loosen the screw 1. Slide the headlight lens unit under. Slide forward Headlight beam raises. Headlight beam low- Slide backward ers. Tighten the screw 1.
  • Page 115 REPLACING THE HEADLIGHT BULB 3.Remove: Cover 1 Bulb holder 2 Bulb NOTE: Turn the bulb holder counterclockwise and remove the defective bulb. WARNING Keep flammable products and your hands away from the bulb while it is on, since it will be hot. Do not touch the bulb until it cools down.

  • Page 116: Chapter 4. Chassis

    CHAS FRONT WHEELS CHASSIS FRONT WHEELS FRONT WHEELS Order Job name/Part name Q’ty Remarks Removing the front wheel Remove the parts in the order below. Place the machine on a level surface. WARNING Securely support the machine so there is no danger of it falling over. Cotter pin Refer to “INSTALLING THE WHEEL HUB”.

  • Page 117: Chas

    CHAS FRONT WHEELS Order Job name/Part name Q’ty Remarks Wheel hub Brake disc For installation, reverse the removal pro- cedure. 4 - 2...

  • Page 118: Checking The Wheel

    CHAS FRONT WHEELS CHECKING THE WHEEL 1.Check: Wheel 2.Measure: Wheel runout Over the specified limit → Replace the wheel or check the wheel bearing play 1. Wheel runout limit: Radial 2: 2.0 mm (0.08 in) Lateral 3: 2.0 mm (0.08 in) 3.Check: Wheel balance Out of balance →...

  • Page 119: Checking The Brake Disc

    CHAS FRONT WHEELS 2.Check: Wheel bearings Wheel hub play/wheel turns roughly → Replace. *********************************************** Wheel bearing replacement steps: Clean wheel hub exterior. Drive bearing out by pushing spacer aside and tapping around perimeter of bearing inner race. Use soft metal drift punch and hammer.

  • Page 120: Installing Wheel Hub

    CHAS FRONT WHEELS INSTALLING WHEEL HUB 1.Install: Axle nut 1 70 Nm (7.0 m • kg, 50 ft • lb) Cotter pin 2 NOTE: Do not loosen the axle nut after torquing it. If the axle nut groove is not aligned with the cot- ter pin hole, align the groove with the hole by tightening the axle nut.

  • Page 121: Rear Wheels, Wheel Axle And Hub

    CHAS REAR WHEELS, WHEEL AXLE AND HUB REAR WHEELS, WHEEL AXLE AND HUB REAR WHEELS Order Job name/Part name Q’ty Remarks Removing the rear wheel Remove the parts in the order below. Place the machine on a level surface. WARNING Securely support the machine so there is no danger of it falling over.

  • Page 122: Wheel Axle And Hub

    CHAS REAR WHEELS, WHEEL AXLE AND HUB WHEEL AXLE AND HUB Order Job name/Part name Q’ty Remarks Removing the wheel axle and hub Remove the parts in the order below. Refer to “INSTALLING THE NUTS (REAR AXLE)”. Locknut Refer to “REMOVING THE REAR AXLE”. Adjusting bolt Rear axle Brake caliper...
  • Page 123 CHAS REAR WHEELS, WHEEL AXLE AND HUB Order Job name/Part name Q’ty Remarks Brake disc Driven sprocket Brake caliper bracket For installation, reverse the removal pro- cedure. 4 - 8...

  • Page 124: Removing The Rear Axle

    CHAS REAR WHEELS, WHEEL AXLE AND HUB REMOVING THE REAR AXLE 1.Place the machine on a level surface. 2.Loosen: Nuts (rear axle) 1 NOTE: Apply the brake pedal so that the rear axle does not turn, when loosening the nuts. Use a axle nut wrench (50 mm) 2.

  • Page 125: Checking The Wheel

    CHAS REAR WHEELS, WHEEL AXLE AND HUB 7.Remove: Rear axle 1 CAUTION: Never directly tap the axle end with a hammer, since this will result in damage to the axle thread and spline. Attach a suitable socket 2 on the axle end and tap it with a soft hammer.

  • Page 126: Checking The Hub

    CHAS REAR WHEELS, WHEEL AXLE AND HUB CHECKING THE HUB 1.Check: Hub bearings Refer to “FRONT WHEELS-WHEEL HUB INSPECTION”. CHECKING THE BRAKE DISC Refer to “FRONT WHEELS”. INSTALLING THE NUTS (REAR AXLE) 1.Tighten: Nuts (rear axle) 1, 2 *********************************************** Nuts tightening steps: NOTE: Before tightening the nuts, apply the LOC- ®...

  • Page 127: Installing The Wheel Hub

    CHAS REAR WHEELS, WHEEL AXLE AND HUB INSTALLING THE WHEEL HUB Refer to “FRONT WHEELS”. INSTALLING THE WHEEL 1.Install: Wheel NOTE: The wording on the tire “SIDE FACING OUT- WARDS” 1 must be facing outwards. 4 - 12...

  • Page 128: Front And Rear Brakes

    CHAS FRONT AND REAR BRAKES FRONT AND REAR BRAKES FRONT BRAKE PADS Order Job name/Part name Q’ty Remarks Removing the front brake pad Remove the parts in the order below. Front wheel/wheel hub Refer to “FRONT WHEELS”. Brake pad holding bolt Refer to “REPLACING THE FRONT Brake pad/pad shim BRAKE PAD”.

  • Page 129: Rear Brake Pads

    CHAS FRONT AND REAR BRAKES REAR BRAKE PADS Order Job name/Part name Q’ty Remarks Removing rear brake pad Remove the parts in the order below. Brake caliper mounting bolt Brake caliper mounting bolt Brake pad holding bolt Refer to “REPLACING THE REAR BRAKE PAD”.

  • Page 130: Replacing The Front Brake Pad

    CHAS FRONT AND REAR BRAKES CAUTION: Disc brake components rarely require dis- assembly. DO NOT: disassemble components unless abso- lutely necessary; use solvents on internal brake compo- nents; use spent brake fluid for cleaning; (use only clean brake fluid) allow brake fluid to come in contact with the eyes, as this may cause eye injury;...
  • Page 131 CHAS FRONT AND REAR BRAKES *********************************************** Installation steps: Connect a suitable hose 1 tightly to the brake caliper bleed screw 2. Put the other end of this hose into an open container. Loosen the brake caliper bleed screw and, using a finger, push the caliper piston into the brake caliper.

  • Page 132: Replacing The Rear Brake Pad

    CHAS FRONT AND REAR BRAKES REPLACING THE REAR BRAKE PAD NOTE: It is not necessary to disassemble the brake caliper and brake hose to replace the brake pads. 1.Remove: Brake pads a Wear limit NOTE: Replace the brake pads as a set if either is found to be worn to the wear limit.
  • Page 133 CHAS FRONT AND REAR BRAKES Brake pad holding bolt: 18 Nm (1.8 m • kg, 13 ft • lb) Brake caliper mounting bolt: 28 Nm (2.8 m • kg, 20 ft • lb) Bend the lock washer tabs along a flat side of the bolts.

  • Page 134: Front Brake Master Cylinder

    CHAS FRONT AND REAR BRAKES FRONT BRAKE MASTER CYLINDER Order Job name/Part name Q’ty Remarks Removing front brake master cylin- Remove the parts in the order below. Brake fluid Drain. Brake fluid reservoir cap Brake fluid reservoir diaphragm Front brake switch Brake lever Union bolt Copper washer...
  • Page 135 CHAS FRONT AND REAR BRAKES Order Job name/Part name Q’ty Remarks Disassembling the front brake mas- Remove the parts in the order below. ter cylinder Dust boot Refer to “ASSEMBLING THE FRONT Circlip AND REAR BRAKE MASTER CYLIN- DER”. Brake master cylinder kit For assembly, reverse the disassembly procedure.

  • Page 136: Rear Brake Master Cylinder

    CHAS FRONT AND REAR BRAKES REAR BRAKE MASTER CYLINDER Order Job name/Part name Q’ty Remarks Removing the rear brake master cyl- Remove the parts in the order below. inder Right footrest guard Refer to “SEAT, FENDERS AND FUEL TANK” in CHAPTER 3. Brake fluid Drain.
  • Page 137 CHAS FRONT AND REAR BRAKES Order Job name/Part name Q’ty Remarks Union bolt Copper washer Refer to “INSTALLING THE REAR BRAKE MASTER CYLINDER”. Brake hose Brake master cylinder For installation, reverse the removal pro- cedure. 4 - 22...
  • Page 138 CHAS FRONT AND REAR BRAKES Order Job name/Part name Q’ty Remarks Disassembling the rear brake mas- Remove the parts in the order below. ter cylinder Hose joint Brake master cylinder kit Refer to “ASSEMBLING THE FRONT AND REAR BRAKE MASTER CYLIN- Brake master cylinder DER”.

  • Page 139: Checking The Master Cylinder

    CHAS FRONT AND REAR BRAKES CHECKING THE MASTER CYLINDER È 1.Check: Brake master cylinder 1 Wear/scratches → Replace the brake master cylinder assembly. Brake master cylinder body Cracks/damage → Replace. Brake fluid delivery passage (brake master cylinder body) Blockage → Blow out with compressed air. È...

  • Page 140: Assembling The Front And Rear Brake Master Cylinder

    CHAS FRONT AND REAR BRAKES EB702060 ASSEMBLING THE FRONT AND REAR BRAKE MASTER CYLINDER WARNING All internal brake components should be cleaned and lubricated with new brake fluid only before installation. Recommended brake fluid: DOT 4 Whenever a master cylinder is disassem- bled, replace the piston seals and dust seals.
  • Page 141 CHAS FRONT AND REAR BRAKES 3.Fill: Brake fluid reservoir Recommended brake fluid: DOT 4 CAUTION: Brake fluid may damage painted surfaces or plastic parts. Always clean up spilled brake fluid immediately. WARNING Use only the designated quality brake fluid: Other brake fluids may deteriorate the rubber seals, causing leakage and poor brake performance.

  • Page 142: Installing The Rear Brake Master Cylinder

    CHAS FRONT AND REAR BRAKES INSTALLING THE REAR BRAKE MASTER CYLINDER 1.Install: Copper washers 1 Brake hose 2 Union bolt 3 30 Nm (3.0 m • kg, 22 ft • lb) CAUTION: When installing the brake hose onto the brake master cylinder, make sure the brake pipe touches the projection a as shown.
  • Page 143 CHAS FRONT AND REAR BRAKES 3.Air bleed: Brake system Refer to “BLEEDING THE HYDRAULIC BRAKE SYSTEM” in CHAPTER 3. 4.Check: Brake fluid level Brake fluid level is below the “LOWER” level line → Add the recommended brake fluid to the proper level. Refer to “CHECKING THE BRAKE FLUID LEVEL”...

  • Page 144: Front Brake Calipers

    CHAS FRONT AND REAR BRAKES FRONT BRAKE CALIPERS Order Job name/Part name Q’ty Remarks Removing the front brake caliper Remove the parts in the order below. Brake fluid Drain. Front wheel Refer to “FRONT WHEELS”. Union bolt Copper washer Brake hose Disconnect.
  • Page 145 CHAS FRONT AND REAR BRAKES Order Job name/Part name Q’ty Remarks Disassembling the front brake cali- Remove the parts in the order below. Brake pad holding bolt Brake pad/pad shim Brake pad spring Retaining bolt Caliper bracket Brake caliper piston Refer to “DISASSEMBLING THE FRONT Dust seal AND REAR BRAKE CALIPER/ASSEM-...

  • Page 146: Rear Brake Caliper

    CHAS FRONT AND REAR BRAKES REAR BRAKE CALIPER Order Job name/Part name Q’ty Remarks Removing the rear brake caliper Remove the parts in the order below. Brake fluid Drain. Parking brake cable Disconnect. Union bolt Copper washer Refer to “INSTALLING Brake hose Disconnect.
  • Page 147 CHAS FRONT AND REAR BRAKES Order Job name/Part name Q’ty Remarks Disassembling the rear brake caliper Remove the parts in the order below. Adjusting bolt Locknut Parking brake lever Parking brake case mounting bolt Parking brake case Gasket Spring Bearing Refer to “ASSEMBLING THE REAR Brake pad holding bolt BRAKE CALIPER”.
  • Page 148 CHAS FRONT AND REAR BRAKES Order Job name/Part name Q’ty Remarks Brake pad/pad shim Brake pad spring Retaining bolt Caliper bracket Brake caliper piston Refer to “DISASSEMBLING THE FRONT Dust seal AND REAR BRAKE CALIPER/ASSEM- Caliper piston seal BLING THE REAR BRAKE CALIPER”. O-ring Bleed screw For assembly, reverse the disassembly...

  • Page 149: Disassembling The Front And Rear Brake Caliper

    CHAS FRONT AND REAR BRAKES DISASSEMBLING THE FRONT AND REAR BRAKE CALIPER 1.Remove: Brake caliper piston Dust seal 1 Caliper piston seal 2 *********************************************** Removal steps: Blow compressed air into the hose joint opening to force out the caliper piston from the brake caliper body.

  • Page 150: Assembling The Front Brake Caliper

    CHAS FRONT AND REAR BRAKES 1.Check: È Brake caliper piston 1 Scratches/rust/wear → Replace the brake caliper assembly. Brake caliper cylinder 2 Wear/scratches → Replace the brake caliper assembly. Brake caliper body 3 Cracks/damage → Replace. Brake fluid delivery passage (brake caliper body) É...

  • Page 151: Assembling The Rear Brake Caliper

    CHAS FRONT AND REAR BRAKES ASSEMBLING THE REAR BRAKE CALIPER WARNING All internal brake components should be cleaned and lubricated with new brake fluid only before installation. Recommended brake fluid: DOT 4 Replace the caliper piston seal whenever a brake caliper is disassembled. 1.Install: O-ring 1 Caliper piston seal 2...

  • Page 152: Installing The Front Brake Caliper

    CHAS FRONT AND REAR BRAKES INSTALLING THE FRONT BRAKE CALIPER 1.Install: Brake caliper assembly Brake caliper mounting bolts 1 28 Nm (2.8 m • kg, 20 ft • lb) Brake hose 2 Copper washers 3 Union bolt 4 27 Nm (2.7 m • kg, 19 ft • lb) CAUTION: When installing the brake hose on the brake caliper, make sure that the brake...

  • Page 153: Installing The Rear Brake Caliper

    CHAS FRONT AND REAR BRAKES 4.Check: Brake fluid level Brake fluid level is below the “LOWER” level line → Add the recommended brake fluid to the proper level. Refer to “CHECKING THE BRAKE FLUID LEVEL” in CHAPTER 3. INSTALLING THE REAR BRAKE CALIPER 1.Install: Brake caliper assembly Brake caliper mounting bolts 1...
  • Page 154 CHAS FRONT AND REAR BRAKES WARNING Use only the designated quality brake fluid: Other brake fluids may deteriorate the rubber seals, causing leakage and poor brake performance. Refill with the same type of brake fluid: Mixing brake fluids may result in a harmful chemical reaction and lead to poor brake performance.

  • Page 155: Steering System

    CHAS STEERING SYSTEM STEERING SYSTEM HANDLEBAR Order Job name/Part name Q’ty Remarks Removing the handlebar Remove the parts in the order below. Handlebar cover Band Front brake switch Refer to “REMOVING THE FRONT BRAKE SWITCH, PARK SWITCH AND CLUTCH SWITCH”. Brake master cylinder/bracket Refer to “INSTALLING THE BRAKE Throttle lever assembly/bracket...
  • Page 156 CHAS STEERING SYSTEM Order Job name/Part name Q’ty Remarks Handlebar grip Refer to “REMOVING/INSTALLING THE HANDLEBAR GRIP”. Handlebar cover bracket Refer to “INSTALLING THE HANDLE- Handlebar holder BAR”. Handlebar For installation, reverse the removal pro- cedure. 4 - 41...

  • Page 157: Removing The Front Brake Switch, Park Switch And Clutch Switch

    CHAS STEERING SYSTEM REMOVING THE FRONT BRAKE SWITCH, PARK SWITCH AND CLUTCH SWITCH 1.Remove: Front brake switch 1 Park switch Clutch switch NOTE: Push the fastener when removing the front brake switch out of the brake master cylin- der. Push the fastener when removing the park switch and clutch switch out of the clutch lever holder.

  • Page 158: Installing The Handlebar

    CHAS STEERING SYSTEM INSTALLING THE HANDLEBAR 1.Install: Handlebar Handlebar holders Handlebar cover brackets 23 Nm (2.3 m • kg, 17 ft • lb) NOTE: The upper handlebar holder should be installed with the punched mark 1 forward 2. CAUTION: First tighten the bolts 3 on the front side of the handlebar holder, and then tighten the bolts 4 on the rear side.

  • Page 159: Installing The Brake Master Cylinder

    CHAS STEERING SYSTEM INSTALLING THE BRAKE MASTER CYLINDER 1.Install: Throttle lever assembly Collar Brake master cylinder 7 Nm (0.7 m • kg, 5.1 ft • lb) NOTE: Engage the indentations a in the collar with the lobes b on the throttle lever assembly and brake master cylinder.

  • Page 160: Steering Stem

    CHAS STEERING SYSTEM STEERING STEM Order Job name/Part name Q’ty Remarks Removing the steering stem Remove the parts in the order below. Front fender Refer to “SEAT, FENDERS AND FUEL TANK” in CHAPTER 3. Fuel tank Handlebar Refer to “HANDLEBAR”. Pitman arm Lock washer Refer to “INSTALLING THE LOCK...
  • Page 161 CHAS STEERING SYSTEM Order Job name/Part name Q’ty Remarks Bearing retainer Refer to “REMOVING/INSTALLING THE BEARING RETAINER”. Bearing For installation, reverse the removal pro- cedure. 4 - 46...

  • Page 162: Removing The Bearing Retainer

    CHAS STEERING SYSTEM REMOVING THE BEARING RETAINER 1.Remove: Bearing retainer (steering stem) Damper rod holder: P/N. YM-01327, 90890-01327 CHECKING THE STEERING STEM 1.Check: Steering stem 1 Bends → Replace. WARNING Do not attempt to straighten a bent stem; this may dangerously weaken the stem. 2.Check: Oil seals 1 Steering stem bushings 2...

  • Page 163: Tie-Rod And Steering Knuckle

    CHAS STEERING SYSTEM TIE-ROD AND STEERING KNUCKLE Order Job name/Part name Q’ty Remarks Removing the tie-rod and steering Remove the parts in the order below. knuckle Front wheel/brake disc Refer to “FRONT WHEELS”. Tie-rod Refer to “INSTALLING THE TIE-ROD”. Pitman arm Brake disc guard (inner) Front bumper Front arm (lower)

  • Page 164: Removing The Steering Knuckle

    CHAS STEERING SYSTEM REMOVING THE STEERING KNUCKLE 1.Remove: Steering knuckle 1 NOTE: Use a general puller to separate the ball joint 2 and steering knuckle. CHECKING THE TIE-ROD 1.Check: Tie-rod free play and movement Free play → Replace the tie-rod end. Turns roughly →...

  • Page 165: Front Arms And Front Shock Absorbers

    CHAS FRONT ARMS AND FRONT SHOCK ABSORBERS FRONT ARMS AND FRONT SHOCK ABSORBERS Order Job name/Part name Q’ty Remarks Removing the front arm and front Remove the parts in the order below. shock absorber Front wheel/brake disc Refer to “FRONT WHEELS”. Front bumper Brake disc guard (inner) Tie-rod...
  • Page 166 CHAS FRONT ARMS AND FRONT SHOCK ABSORBERS Order Job name/Part name Q’ty Remarks Nut/bolt Front shock absorber/collar Steering knuckle Dust cover Collar Collar Bushing Circlip Rubber boot Ball joint For installation, reverse the removal pro- cedure. 4 - 51...

  • Page 167: Removing The Front Arm

    CHAS FRONT ARMS AND FRONT SHOCK ABSORBERS REMOVING THE FRONT ARM 1.Check: Front arm free play *********************************************** Checking steps: Check the front arm side play È by moving it from side to side. If side play is noticeable, check the bushings. Check the front arm vertical movement É...

  • Page 168: Checking The Ball Joint

    CHAS FRONT ARMS AND FRONT SHOCK ABSORBERS CHECKING THE BALL JOINT 1.Check: Ball joint (front arm-upper) Damage/pitting → Replace the front arm (upper). Free play → Replace the front arm. Turns roughly → Replace the front arm (upper). 2.Check: Ball joint (front arm-lower) Damage/pitting →...

  • Page 169: Installing The Front Arm

    CHAS FRONT ARMS AND FRONT SHOCK ABSORBERS Attach the assembled ball joint remover/ installer, new ball joint A, installer spacer 7 and installer washer 8 to the front lower arm NOTE: Do not tap or damage the top of the ball joint. Installer spacer 7 must be aligned with the projection on the head of the ball joint A.

  • Page 170: Rear Shock Absorber And Relay Arm

    CHAS REAR SHOCK ABSORBER AND RELAY ARM REAR SHOCK ABSORBER AND RELAY ARM Order Job name/Part name Q’ty Remarks Removing the rear shock absorber Remove the parts in the order below. and relay arm Rear wheels and hub Refer to “REAR WHEELS, WHEEL AXLE AND HUB”.
  • Page 171 CHAS REAR SHOCK ABSORBER AND RELAY ARM Order Job name/Part name Q’ty Remarks Self-locking nut/bolt Relay arm Spacer/oil seal/bushing 1/2/2 Refer to “INSTALLING THE RELAY ARM AND CONNECTING ARM”. Connecting arm Dust cover Spacer Spacer Bushing Refer to “INSTALLING THE RELAY ARM AND CONNECTING ARM”.

  • Page 172: Handling The Rear Shock Absorber And Gas Cylinder

    CHAS REAR SHOCK ABSORBER AND RELAY ARM HANDLING THE REAR SHOCK ABSORBER AND GAS CYLINDER WARNING This rear shock absorber and gas cylinder contain highly compressed nitrogen gas. Before handling the rear shock absorber or gas cylinder, read and make sure you understand the following information.

  • Page 173: Checking The Rear Shock Absorber

    CHAS REAR SHOCK ABSORBER AND RELAY ARM REMOVING THE REAR SHOCK ABSORBER 1.Remove: Connecting arm-to-frame bolt Rear shock absorber upper bolt NOTE: While removing the connecting arm-to-frame bolt, hold the swingarm so that it does not drop down. CHECKING THE REAR SHOCK ABSORBER 1.Check: Shock absorber Oil leaks →...

  • Page 174: Installing The Relay Arm And Connecting Arm

    CHAS REAR SHOCK ABSORBER AND RELAY ARM INSTALLING THE RELAY ARM AND CONNECTING ARM 1.Install: Bushing 1 (to connecting arm) NOTE: Apply the lithium soap base grease on the bushing when installing. Installed depth of bushing a: 1 mm (0.04 in) 2.Install: Bushing 1 Oil seal 2...

  • Page 175: Swingarm And Drive Chain

    CHAS SWINGARM AND DRIVE CHAIN SWINGARM AND DRIVE CHAIN Order Job name/Part name Q’ty Remarks Removing the swingarm and drive Remove the parts in the order below. chain Rear wheels and hub Refer to “REAR WHEELS, WHEEL AXLE AND HUB”. Rear shock absorber Refer to “REAR SHOCK ABSORBER AND RELAY ARM”.
  • Page 176 CHAS SWINGARM AND DRIVE CHAIN Order Job name/Part name Q’ty Remarks Refer to “INSTALLING THE DRIVE Lock washer SPROCKET”. Drive sprocket Drive chain Collar Spacer Oil seal Bearing Dust cover/oil seal/washer 1/1/1 Spacer Oil seal Bushing Refer to “INSTALLING THE SWING- ARM”.

  • Page 177: Removing The Swingarm

    CHAS SWINGARM AND DRIVE CHAIN NOTE: Before removing the drive chain and the sprockets, measure the drive chain slack and a ten link section of the drive chain. REMOVING THE SWINGARM 1.Check: Swingarm free play *********************************************** Checking steps: Check the tightening torque of the pivot shaft nut.

  • Page 178: Checking The Drive Chain

    CHAS SWINGARM AND DRIVE CHAIN 2.Check: Pivot shaft Roll the axle on a flat surface. Bends → Replace. WARNING Do not attempt to straighten a bent pivot shaft. 3.Clean: Pivot shaft Collar Spacers Bearings Bushings Recommended cleaning solvent: Kerosine 4.Check: Spacers Oil seals Damage/wear →...
  • Page 179 CHAS SWINGARM AND DRIVE CHAIN 2.Check: Drive chain Stiffness → Clean and lubricate or replace. 3.Clean: Drive chain *********************************************** Wipe the drive chain with a clean cloth. Put the drive chain in kerosine and remove any remaining dirt. Remove the drive chain from the kerosine and completely dry it.

  • Page 180: Installing The Swingarm

    CHAS SWINGARM AND DRIVE CHAIN 5.Lubricate: Drive chain Recommended lubricant: Engine oil or chain lubricant suitable for O-ring chains 6.Check: Drive sprocket Driven sprocket More than 1/4 tooth a wear → Replace the drive chain sprockets as a set. Bent teeth → Replace the drive chain sprockets as a set.

  • Page 181: Chapter 5. Engine

    ENGINE REMOVAL ENGINE ENGINE REMOVAL MUFFLER AND EXHAUST PIPES Order Job name/Part name Q’ty Remarks Removing the muffler and exhaust Remove the parts in the order below. pipes Seat/left footrest guard/engine Skid plate Refer to “SEAT, FENDERS AND FUEL TANK” in CHAPTER 3. Front and rear fenders Fuel tank and rubber covers Muffler...

  • Page 182: Left Footrest

    ENGINE REMOVAL LEFT FOOTREST Order Job name/Part name Q’ty Remarks Removing the left footrest Remove the parts in the order below. Locknut Locknut Left-hand threads Adjusting rod Left footrest guard bracket Left footrest For installation, reverse the removal pro- cedure. 5 - 2...

  • Page 183: Leads, Cables And Hoses

    ENGINE REMOVAL LEADS, CABLES AND HOSES Order Job name/Part name Q’ty Remarks Removing the leads, cables and Remove the parts in the order below. hoses Engine oil Drain. Coolant Drain. Water jacket outlet pipe Refer to “THERMOSTAT” in CHAPTER 6. Radiator outlet hose Refer to “WATER PUMP”...
  • Page 184 ENGINE REMOVAL Order Job name/Part name Q’ty Remarks Coupler Disconnect. Speed sensor/O-ring Neutral switch lead/reverse switch lead Ground lead Clutch cable Parking brake cable Reverse control cable Oil pipe 2 Disconnect. Oil pipe 1 Disconnect. Oil tank breather hose Disconnect. Crankcase breather hose Disconnect.

  • Page 185: Engine Mounting Bolts

    ENGINE REMOVAL ENGINE MOUNTING BOLTS Order Job name/Part name Q’ty Remarks Removing the engine mounting bolt Remove the parts in the order below. Engine mounting bolt (upper)/nut Engine bracket bolt (upper) Engine bracket (upper) Engine mounting bolt (middle)/nut CAUTION: Engine mounting bolt (lower)/nut Install all of the bolts/nuts and then Engine bracket (middle-left) tighten them to full torque specifica-...
  • Page 186 ENGINE REMOVAL Order Job name/Part name Q’ty Remarks Engine assembly NOTE: Remove the engine assembly from the left side of the machine. For installation, reverse the removal pro- cedure. 5 - 6...

  • Page 187: Installing The Engine

    ENGINE REMOVAL INSTALLING THE ENGINE 1.Install: Engine brackets (lower) 1 Engine bracket bolts (lower) 2 Engine brackets (middle) 3 Engine mounting bolt (lower)/nut 4 Engine mounting bolt (middle)/nut 5 Engine bracket (upper) 6 Engine bracket bolts (upper) 7 Engine mounting bolt (upper)/nut 8 NOTE: Do not fully tighten the bolts and nuts.

  • Page 188: Cylinder Head Cover

    CYLINDER HEAD COVER CYLINDER HEAD COVER Order Job name/Part name Q’ty Remarks Removing the cylinder head cover Remove the parts in the order below. Seat/front fender Refer to “SEAT, FENDERS AND FUEL TANK” in CHAPTER 3. Fuel tank/rubber cover 2 Engine mounting bolt/nut Engine bracket (front-upper) Oil tank breather hose...
  • Page 189 CYLINDER HEAD COVER Order Job name/Part name Q’ty Remarks Cylinder head cover Refer to “REMOVING/INSTALLING CYL- INDER HEAD COVER”. Dowel pin For installation, reverse the removal pro- cedure. 5 - 9...

  • Page 190: Removing The Cylinder Head Cover

    CYLINDER HEAD COVER REMOVING THE CYLINDER HEAD COVER 1.Align: “I” mark (with stationary pointer) *********************************************** Checking steps: Turn the crankshaft counterclockwise with a wrench. Align the “I” mark 1 on the rotor with the sta- tionary pointer 2 on the crankcase cover. When the “I”...

  • Page 191: Eng

    (to the mating surfaces of the cylinder head and cylinder head cover)  ) 1: Sealant (Quick Gasket P/N. ACC-11001-05-01  Yamaha bond No. 1215 P/N. 90890-85505 2.Install: Cylinder head cover Cable guides 1 Washers 2 Bolts 10 Nm (1.0 m • kg, 7.2 ft • lb)

  • Page 192: Rocker Arms

    ROCKER ARMS ROCKER ARMS Order Job name/Part name Q’ty Remarks Removing the rocker arm Remove the parts in the order below. Cylinder head cover Refer to “CYLINDER HEAD COVER”. Plug/O-ring Bolt Rocker arm shaft 2/O-ring Rocker arm 3 Rocker arm shaft 3/O-ring Refer to “REMOVING/INSTALLING THE Rocker arm 4 ROCKER ARM”.
  • Page 193 ROCKER ARMS Order Job name/Part name Q’ty Remarks Spring Locknut Valve adjuster For installation, reverse the removal pro- cedure. 5 - 13...

  • Page 194: Removing The Rocker Arm

    ROCKER ARMS REMOVING THE ROCKER ARM 1.Remove: Rocker arm shafts 1 Rocker arms 2 NOTE: Use a slide hammer bolt 3 and weight 4 to remove the rocker arm shafts. Slide hammer set: P/N. YU-01083-A Slide hammer bolt (M6): P/N. 90890-01083 Weight: P/N.

  • Page 195: Installing The Rocker Arm

    ROCKER ARMS Measure the outside diameter b of the rocker arm shafts. Out of specification → Replace. Rocker arm outside diameter: 11.976 ~ 11.991 mm (0.4715 ~ 0.4721 in) Calculate the clearance by subtracting the rocker arm shaft outside diameter from the rocker arm inside diameter.

  • Page 196: Camshaft And Cylinder Head

    CAMSHAFT AND CYLINDER HEAD CAMSHAFT AND CYLINDER HEAD Order Job name/Part name Q’ty Remarks Removing the camshaft and cylin- Remove the parts in the order below. der head Seat/front fender Refer to “SEAT, FENDERS AND FUEL TANK” in CHAPTER 3. Fuel tank/rubber covers Carburetors Refer to “CARBURETORS”...
  • Page 197 CAMSHAFT AND CYLINDER HEAD Order Job name/Part name Q’ty Remarks Camshaft Refer to “CAMSHAFT AND CYLINDER HEAD”. Cylinder head Cylinder head gasket Dowel pin Carburetor joint 1 Carburetor joint 2 For installation, reverse the removal pro- cedure. 5 - 17...

  • Page 198: Removing The Camshaft And Cylinder Head

    CAMSHAFT AND CYLINDER HEAD REMOVING THE CAMSHAFT AND CYLIN- DER HEAD 1.Loosen: Camshaft sprocket bolts 1 2.Loosen: Timing chain tensioner cap bolt 3.Remove: Timing chain tensioner Timing chain guide (exhaust) Decompressor cam guide plates Camshaft sprocket NOTE: Fasten a safety wire to the timing chain to prevent it from falling into the crankcase.

  • Page 199: Checking The Camshaft

    CAMSHAFT AND CYLINDER HEAD CHECKING THE CAMSHAFT 1.Check: Cam lobes Pitting/scratches/blue discoloration → Replace. 2.Measure: Cam lobes length a and b. Out of specification → Replace. Camshaft lobe limit: Intake: a 35.59 mm (1.4012 in) b 30.05 mm (1.1831 in) Exhaust: a 36.40 mm (1.4331 in) b 30.05 mm (1.1831 in)

  • Page 200: Checking The Timing Chain Guide

    CAMSHAFT AND CYLINDER HEAD CHECKING THE TIMING CHAIN GUIDE 1.Check: Exhaust side timing chain guide Wear/damage → Replace. CHECKING THE TIMING CHAIN TEN- SIONER 1.Check: One-way cam operation (tensioner) Unsmooth operation → Replace. CHECKING THE CYLINDER HEAD 1.Eliminate: Carbon deposits (from the combustion chambers) Use a rounded scraper.

  • Page 201: Installing The Camshaft And Cylinder Head

    CAMSHAFT AND CYLINDER HEAD 3.Measure: Cylinder head warpage Out of specification → Resurface. Cylinder head warpage: Less than 0.05 mm (0.002 in) *********************************************** Warpage measurement and resurfacing steps: Place a straightedge and a feeler gauge across the cylinder head. Use a feeler gauge to measure the warpage. If the warpage is out of specification, resur- face the cylinder head.
  • Page 202 CAMSHAFT AND CYLINDER HEAD 2.Install: Camshaft Camshaft sprocket *********************************************** Installation steps: Turn the crankshaft counterclockwise with a wrench. Align the “I” mark 1 on the rotor with the sta- tionary pointer 2 on the crankcase cover. When the “I” mark is aligned with the station- ary pointer, the piston is at the Top Dead Center (T.D.C.).
  • Page 203 CAMSHAFT AND CYLINDER HEAD Install the decompressor cam guide plates 9 and camshaft sprocket bolts 0. Camshaft sprocket bolt: 20 Nm (2.0 m • kg, 14 ft • lb) Remove the retaining wire. *********************************************** 3.Install: Timing chain tensioner *********************************************** Installation steps: Remove the timing chain tensioner cap bolt 1, washer 2 and spring 3.

  • Page 204: Valves And Valve Springs

    VALVES AND VALVE SPRINGS VALVES AND VALVE SPRINGS Order Job name/Part name Q’ty Remarks Removing the valve and valve Remove the parts in the order below. spring Cylinder head Refer to “CAMSHAFT AND CYLINDER HEAD”. Valve cotter Valve spring retainer Intake valve spring Exhaust valve spring Refer to “REMOVING/INSTALLING THE...

  • Page 205: Removing The Valve And Valve Spring

    VALVES AND VALVE SPRINGS REMOVING THE VALVE AND VALVE SPRING 1.Check: Valve sealing Leakage at the valve seat → Inspect the valve face, valve seat and valve seat width. Refer to “VALVE AND VALVE SPRING INSPECTION”. *********************************************** Checking steps: Pour a clean solvent 1 into the intake and exhaust ports.

  • Page 206: Checking The Valve And Valve Spring

    VALVES AND VALVE SPRINGS CHECKING THE VALVE AND VALVE SPRING 1.Measure: Stem-to-guide clearance Stem-to-guide clearance = valve guide inside diameter a – valve stem diameter b Out of specification → Replace the valve guide. Clearance (stem to guide): Intake: 0.010 ~ 0.037 mm (0.0004 ~ 0.0015 in) <Limit>: 0.08 mm (0.0031 in) Exhaust:...
  • Page 207 VALVES AND VALVE SPRINGS 3.Check: Valve face Pitting/wear → Grind the face. Valve stem end Mushroom shape or diameter larger than the body of the stem → Replace. 4.Measure: Margin thickness a Out of specification → Replace. Margin thickness: Intake: 0.85 ~ 1.15 mm (0.0335 ~ 0.0453 in) Exhaust:...
  • Page 208 VALVES AND VALVE SPRINGS 8.Measure: Valve seat width a Out of specification → Reface the valve seat. Valve seat width: Intake: 0.9 ~ 1.1 mm (0.0354 ~ 0.0433 in) <Limit>: 1.6 mm (0.0630 in) Exhaust: 0.9 ~ 1.1 mm (0.0354 ~ 0.0433 in) <Limit>: 1.6 mm (0.0630 in) *********************************************** Measurement steps:...
  • Page 209 VALVES AND VALVE SPRINGS Install the valve into the cylinder head. Turn the valve until the valve face and valve seat are evenly polished, then clean off all of the compound. NOTE: For best lapping results, lightly tap the valve seat while rotating the valve back and forth between your hands.

  • Page 210: Installing The Valve And Valve Spring

    VALVES AND VALVE SPRINGS 11.Measure: Compressed spring force a Out of specification → Replace. b Installed length Compressed spring force: Inner: 149 ~ 173 N at 27.2 mm (15.19 ~ 17.64 kg, 33.50 ~ 38.89 lb at 1.07 in) Outer: 165 ~ 191 N at 30.7 mm (16.83 ~ 19.49 kg, 37.09 ~ 42.94 lb at 1.21 in)
  • Page 211 VALVES AND VALVE SPRINGS 3.Install: Valve cotters NOTE: Install the valve cotters while compressing the valve spring with the valve spring compressor 1 and attachment 2. Valve spring compressor: P/N. YM-04019, 90890-04019 Valve spring compressor attachment: P/N. 90890-01243 4.To secure the valve cotters onto the valve stem, lightly tap the valve tip with a piece of wood.

  • Page 212: Cylinder And Piston

    CYLINDER AND PISTON CYLINDER AND PISTON Order Job name/Part name Q’ty Remarks Removing the cylinder and piston Remove the parts in the order below. Water jacket inlet housing Refer to “WATER PUMP” in CHAPTER 6. Cylinder head Refer to “CAMSHAFT AND CYLINDER HEAD”.

  • Page 213: Removing The Piston

    CYLINDER AND PISTON REMOVING THE PISTON 1.Remove: Piston pin clips 1 Piston pin 2 Piston 3 NOTE: Put identification marks on each piston head for reference during reinstallation. Before removing each piston pin, deburr the clip groove and pin hole area. If the piston pin groove is deburred and the piston pin is still difficult to remove, use the piston pin puller 4.
  • Page 214 CYLINDER AND PISTON NOTE: Measure cylinder bore “C” in parallel to and at right angles to the cylinder matching surface. Then, find the average of the measurements. Standard Wear limit 100.005 ~ Cylinder 100.100 mm 100.045 mm bore “C” (3.9404 in) (3.9372 ~ 3.9388 in) If out of specification, rebore or replace the cylinder, and replace the piston and piston...

  • Page 215: Checking The Piston Ring

    CYLINDER AND PISTON CHECKING THE PISTON RING 1.Measure: Ring side clearance Use a feeler gauge. Out of specification → Replace the piston and rings as a set. NOTE: Clean carbon from the piston ring grooves and rings before measuring the side clearance. Side clearance Standard Limit...

  • Page 216: Checking The Piston Pin Inspection

    CYLINDER AND PISTON CHECKING THE PISTON PIN INSPECTION 1.Check: Piston pin Blue discoloration/grooves → Replace, then inspect the lubrication system. 2.Measure: Piston pin-to-piston clearance *********************************************** Measurement steps: Measure the piston pin outside diameter a. If out of specification, replace the piston pin. Outside diameter (piston pin): 21.991 ~ 22.000 mm (0.8658 ~ 0.8661 in)

  • Page 217: Installing The Cylinder

    CYLINDER AND PISTON 2.Position: Top ring 2nd ring Oil ring Offset the piston ring end gaps as shown. a Top ring end b Oil ring end (lower) c Oil ring end (upper) d 2nd ring end 3.Install: Piston 1 Piston pin 2 Piston pin clips 3 NOTE: Apply engine oil onto the piston pin, piston...

  • Page 218: Ac Magneto

    AC MAGNETO AC MAGNETO Order Job name/Part name Q’ty Remarks Removing the AC magneto Remove the parts in the order below. Engine oil Drain. Shift pedal link Disconnect. Oil pipe 1 Disconnect. AC magneto coupler Starter idle gear cover/gasket Dowel pin Starter idle gear 1 Starter idle gear 1 shaft Bearing...
  • Page 219 AC MAGNETO Order Job name/Part name Q’ty Remarks Dowel pin/O-ring Lead holder Pickup coil Stator assembly Starter idle gear 2 Starter idle gear 2 shaft Bearing AC magneto rotor Refer to “REMOVING/INSTALLING THE AC MAGNETO ROTOR”. Starter wheel gear Woodruff key Bearing/washer For installation, reverse the removal pro- cedure.

  • Page 220: Removing The Ac Magneto Rotor

    AC MAGNETO REMOVING THE AC MAGNETO ROTOR 1.Remove: AC magneto cover NOTE: Loosen each bolt 1/4 of a turn at a time, in stages and in a crisscross pattern. After all of the bolts are fully loosened, remove them. 2.Remove: AC magneto rotor nut 1 Washer NOTE:...

  • Page 221: Checking The Starter Clutch

    AC MAGNETO CHECKING THE STARTER CLUTCH 1.Check: Starter one-way clutch 1 Cracks/damage → Replace. Bolts 2 (starter clutch) Loose → Replace. NOTE: The arrow mark on the starter clutch must face inward, away from the AC magneto rotor. Bolts (starter clutch): 16 Nm (1.6 m •...

  • Page 222: Installing The Ac Magneto Rotor

    ® Sealant (Quick Gasket (into the slit) ® Sealant (Quick Gasket P/N. ACC-11001-05-01 ® Yamaha bond No. 1215 P/N. 90890-85505 2.Install: Woodruff key AC magneto rotor NOTE: Before installing the rotor, clean the outside of the crankshaft and the inside of the rotor.

  • Page 223: Clutch

    CLUTCH CLUTCH Order Job name/Part name Q’ty Remarks Removing the clutch cover Remove the parts in the order below. Engine assembly Refer to “ENGINE REMOVAL”. Oil filter bolt Union bolt Copper washer Oil delivery pipe 1 Union bolt Copper washer Oil delivery pipe 2 Clutch cover Refer to “REMOVING/INSTALLING THE...
  • Page 224 CLUTCH Order Job name/Part name Q’ty Remarks Removing the pull lever shaft Remove the parts in the order below. Circlip Pull lever Pull lever spring Bolt Pull lever shaft Oil seal Bearing Bearing For installation, reverse the removal pro- cedure. 5 - 44...
  • Page 225 CLUTCH Order Job name/Part name Q’ty Remarks Removing the clutch Remove the parts in the order below. Clutch spring Pressure plate Refer to “INSTALLING THE CLUTCH”. Pull rod Bearing Friction plate 2 Inside diameter = 116 mm (4.57 in) Clutch plate Friction plate 1 Inside diameter = 112 mm (4.41 in) Cushion spring...
  • Page 226 CLUTCH Order Job name/Part name Q’ty Remarks Thrust washer Clutch housing Refer to “INSTALLING THE CLUTCH”. Lock washer Balancer driven gear Straight key Refer to “REMOVING/INSTALLING THE Lock washer PRIMARY DRIVE GEAR AND BAL- Primary drive gear ANCER DRIVEN GEAR”. Balancer drive gear Spring Dowel pin...

  • Page 227: Removing The Primary Drive Gear And Balancer Driven Gear

    CLUTCH REMOVING THE CLUTCH 1.Remove: Clutch cover NOTE: Loosen each bolt 1/4 of a turn at a time, in stages and in a crisscross pattern. After all of the bolts are fully loosened, remove them. 2.Straighten the lock washer tab. 3.Loosen: Clutch boss nut 1 NOTE:...

  • Page 228: Checking The Friction Plate

    CLUTCH CHECKING THE FRICTION PLATE The following procedure applies to all of the friction plates. 1.Check: Friction plate Damage/wear → Replace the friction plates as a set. 2.Measure: Friction plate thickness Out of specification → Replace the friction plates as a set. NOTE: Measure the friction plate at four places.

  • Page 229: Checking The Clutch Spring

    CLUTCH CHECKING THE CLUTCH SPRING The following procedure applies to all of the clutch springs. 1.Check: Clutch spring Damage → Replace the clutch springs as a set. 2.Measure: Clutch spring free length a Out of specification → Replace the clutch springs as a set.

  • Page 230: Checking The Pull Lever Shaft And Pull Rod

    CLUTCH CHECKING THE PULL LEVER SHAFT AND PULL ROD 1.Check: Pull lever shaft pinion gear teeth a Pull rod teeth b Damage/wear → Replace the pull lever shaft and pull rod as a set. 2.Check: Pull rod bearing Damage/wear → Replace. CHECKING THE PRIMARY DRIVE 1.Check: Primary drive gear 1...

  • Page 231: Installing The Primary Drive Gear And Balancer Driven Gear

    CLUTCH INSTALLING THE PRIMARY DRIVE GEAR AND BALANCER DRIVEN GEAR 1.Install: Dowel pin Spring Balancer drive gear (onto the primary drive gear) NOTE: Align the punch mark a on the balancer drive gear with the punch mark b on the primary drive gear.

  • Page 232: Installing The Clutch

    CLUTCH INSTALLING THE CLUTCH 1.Install: Clutch housing 1 NOTE: Make sure that the primary driven gear teeth and primary drive gear teeth mesh correctly. Make sure that the oil pump drive gear teeth and oil pump driven gear teeth mesh cor- rectly.
  • Page 233 CLUTCH 5.Install: Clutch spring 8 Nm (0.8 m • kg, 5.8 ft • lb) NOTE: Tighten the bolts in stages, using a crisscross pattern. 6.Install: Clutch cover NOTE: Be sure to mesh the pull lever shaft with the pull rod teeth to ensure that the mark a on pull lever 1 is at the closest position to stationary pointer b onto the clutch cover when the clutch is engaged.

  • Page 234: Oil Pump

    OIL PUMP OIL PUMP Order Job name/Part name Q’ty Remarks Removing the oil pump Remove the parts in the order below. Clutch Refer to “CLUTCH”. Circlip Oil pump driven gear Oil pump Oil pump gasket O-ring For installation, reverse the removal pro- cedure.
  • Page 235 OIL PUMP Order Job name/Part name Q’ty Remarks Disassembling the oil pump Remove the parts in the order below. Oil pump housing 1/oil seal Oil pump outer rotor 1 Dowel pin Oil pump inner rotor 1 Oil pump housing cover/oil seal Dowel pin Oil pump shaft Dowel pin...

  • Page 236: Checking The Oil Pump

    OIL PUMP CHECKING THE OIL PUMP 1.Check: Oil pump driven gear Oil pump housings Oil pump housing cover Cracks/wear/damage → Replace. 2.Measure: Tip clearance a (between the inner rotor 1 and the outer rotor 2) Side clearance b (between the outer rotor 2 and the pump housing 3) Out of specification →...

  • Page 237: Shift Shaft

    SHIFT SHAFT SHIFT SHAFT Order Job name/Part name Q’ty Remarks Removing the shift shaft Remove the parts in the order below. Clutch Refer to “CLUTCH”. Shift arm Shift shaft Refer to “INSTALLING THE SHIFT Shift shaft spring SHAFT”. Collar Roller Stopper lever Refer to “INSTALLING THE STOPPER Stopper lever spring...
  • Page 238 SHIFT SHAFT Order Job name/Part name Q’ty Remarks Shift guide Shift lever Pawl Refer to “INSTALLING THE SHIFT Pawl pin LEVER”. Spring Segment Oil seal For installation, reverse the removal pro- cedure. 5 - 58...

  • Page 239: Checking The Shift Shaft

    SHIFT SHAFT CHECKING THE SHIFT SHAFT 1.Check: Shift shaft 1 Bends/damage/wear → Replace. Shift shaft spring 2 Damage/wear → Replace. CHECKING THE STOPPER LEVER 1.Check: Stopper lever 1 Bends/damage → Replace. Roller turns roughly → Replace the stopper lever. Stopper spring 2 Damage →...

  • Page 240: Installing The Stopper Lever

    SHIFT SHAFT 2.Install: Springs 1 Pawl pins 2 Pawls 3 Shift guide 4 (to the shift lever) 3.Install: Shift lever assembly 1 Shift guide 2 NOTE: The shift lever assembly is installed at the same time as the shift guide. INSTALLING THE STOPPER LEVER 1.Install: Roller...

  • Page 241: Installing The Shift Shaft

    SHIFT SHAFT INSTALLING THE SHIFT SHAFT 1.Install: Roller 1 Collar Shift shaft spring Shift shaft 2 NOTE: Install the end of the shift shaft spring onto the shift shaft spring stopper 3. Install the end of the shift shaft lever onto the roller 1.

  • Page 242: Crankcase

    CRANKCASE CRANKCASE TIMING CHAIN AND SPEED SENSOR ROTOR Order Job name/Part name Q’ty Remarks Removing the timing chain and Remove the parts in the order below. speed sensor rotor Engine assembly Refer to “ENGINE REMOVAL”. Cylinder head cover Refer to “CYLINDER HEAD COVER”. Cylinder head Refer to “CAMSHAFT AND CYLINDER HEAD”.
  • Page 243 CRANKCASE Order Job name/Part name Q’ty Remarks Reverse shift lever Reverse shift lever spring Circlip Neutral switch Reverse switch Oil pipe joint Circlip Wave washer Speed sensor rotor Circlip For installation, reverse the removal pro- cedure. 5 - 63...

  • Page 244: Crankcase

    CRANKCASE CRANKCASE Order Job name/Part name Q’ty Remarks Separating the crankcase Remove the parts in the order below. Right crankcase Dowel pin Refer to “CRANKCASE”. Dowel pin/O-ring Left crankcase Oil strainer Cover Oil strainer gasket For installation, reverse the removal pro- cedure.

  • Page 245: Crankcase Bearing

    CRANKCASE CRANKCASE BEARING Order Job name/Part name Q’ty Remarks Removing the crankcase bearing Remove the parts in the order below. Crankshaft and balancer Refer to “CRANKSHAFT AND BAL- ANCER”. Transmission Refer to “TRANSMISSION”. Oil seal retainer Oil seal Bearing retainer Bearing For installation, reverse the removal pro- cedure.

  • Page 246: Separating The Crankcase

    CRANKCASE SEPARATING THE CRANKCASE È 1.Separate: Left crankcase Right crankcase *********************************************** Separation steps: Remove the crankcase bolts. NOTE: Loosen each bolt 1/4 of a turn at a time and after all the bolts are loosened, remove É them. Loosen the bolts in stages, using a criss- cross pattern.

  • Page 247: Checking The Crankcase

    Roughness → Replace. ASSEMBLING THE CRANKCASE 1.Apply: ® Sealant (Quick Gasket (to the mating surfaces of both case halves) ® Sealant (Quick Gasket P/N. ACC-11001-05-01 Yamaha bond No. 1215: P/N. 90890-85505 2.Install: Dowel pin 2 O-ring 3 5 - 67...
  • Page 248 CRANKCASE 3.Fit the right crankcase onto the left crank- case. Tap lightly on the case with a soft ham- mer. CAUTION: Before installing and torquing the crank- case holding bolts, be sure to check whether the transmission is functioning properly by manually rotating the shift cam in both directions.

  • Page 249: Crankshaft And Balancer

    CRANKSHAFT AND BALANCER CRANKSHAFT AND BALANCER Order Job name/Part name Q’ty Remarks Removing the crankshaft and bal- Remove the parts in the order below. ancer Crankcase Separate. Refer to “CRANKCASE”. Balancer Crankshaft Refer to “REMOVING/INSTALLING THE CRANKSHAFT”. For installation, reverse the removal pro- cedure.

  • Page 250: Removing The Crankshaft

    CRANKSHAFT AND BALANCER REMOVING THE CRANKSHAFT 1.Remove: Crankshaft Use a crankcase separating tool 1. Crankcase separating tool: P/N. YU-01135-A, 90890-01135 CHECKING THE CRANKSHAFT 1.Measure: Crank width A Out of specification → Replace the crank- shaft. Crank width: 74.95 ~ 75.00 mm (2.9508 ~ 2.9528 in) Side clearance D Out of specification →...

  • Page 251: Installing The Crankshaft

    CRANKSHAFT AND BALANCER INSTALLING THE CRANKSHAFT 1.Install: Crankshaft Crankshaft installer pot 1: P/N. 90890-01274 Crankshaft installer bolt 2: P/N. 90890-01275 Crankshaft installer set 3: P/N. YU-90050 Adapter 4: P/N. YM-90069, 90890-04059 Spacer (crankshaft installer) 5: P/N. YM-91044, 90890-04081 Spacer 6: P/N.

  • Page 252: Transmission

    TRANSMISSION TRANSMISSION Order Job name/Part name Q’ty Remarks Removing the transmission Remove the parts in the order below. Crankcase Separate. Refer to “CRANKCASE”. Shift fork guide bar (short) Shift fork “C” Shift fork guide bar (long) Refer to “INSTALLING THE TRANSMIS- SION”.
  • Page 253 TRANSMISSION Order Job name/Part name Q’ty Remarks Counter axle Counter gear For installation, reverse the removal pro- cedure. 5 - 73...

  • Page 254: Main Axle

    TRANSMISSION MAIN AXLE Order Job name/Part name Q’ty Remarks Disassembling the main axle Remove the parts in the order below. Reverse pinion gear 4th pinion gear 2nd/3rd pinion gear Circlip Refer to “ASSEMBLING THE MAIN AXLE AND DRIVE AXLE”. Toothed washer 5th pinion gear Main axle/1st pinion gear For assembly, reverse the disassembly...

  • Page 255: Drive Axle

    TRANSMISSION DRIVE AXLE Order Job name/Part name Q’ty Remarks Disassembling the drive axle Remove the parts in the order below. Washer 1st wheel gear 5th wheel gear Circlip Refer to “ASSEMBLING THE MAIN AXLE AND DRIVE AXLE”. Toothed washer 3rd wheel gear Toothed collar Toothed lock washer Toothed lock washer retainer...
  • Page 256 TRANSMISSION Order Job name/Part name Q’ty Remarks 4th wheel gear Reverse wheel gear Collar Drive axle For assembly, reverse the disassembly procedure. 5 - 76...

  • Page 257: Checking The Shift Fork

    TRANSMISSION CHECKING THE SHIFT FORK 1.Check: Shift fork cam follower 1 Shift fork pawl 2 Scoring/bends/wear/damage → Replace. 2.Check: Guide bar Roll the guide bar on a flat surface. Bends → Replace. WARNING Do not attempt to straighten a bent guide bar.

  • Page 258: Assembling The Main Axle And Drive Axle

    TRANSMISSION 2.Measure: Drive axle runout (with a centering device and dial gauge 1) Out of specification → Replace the drive axle. Maximum drive axle runout: 0.08 mm (0.0031 in) 3.Check: Transmission gears Blue discoloration/pitting/wear → Replace the defective gear(s). Transmission gear dogs Cracks/damage/rounded edges →...

  • Page 259: Installing The Transmission

    TRANSMISSION 2.Install: Reverse pinion gear 1 NOTE: Press the reverse pinion gear into the main axle 2, as shown in the illustration. a 115.65 ~ 115.85 mm (4.553 ~ 4.561 in) INSTALLING THE TRANSMISSION 1.Install: Shift drum 1 Shift fork “L” 2 Shift fork “R”...

  • Page 260: Cooling System

    COOL RADIATOR COOLING SYSTEM RADIATOR Order Job name/Part name Q’ty Remarks Removing the radiator Remove the parts in the order below. Front panel and front fender Refer to “SEAT, FENDERS AND FUEL TANK” in CHAPTER 3. Coolant Drain. Radiator fan coupler Disconnect.
  • Page 261 COOL RADIATOR Order Job name/Part name Q’ty Remarks Coolant reservoir Coolant reservoir cap For installation, reverse the removal pro- cedure. 6 - 2...

  • Page 262: Cool

    COOL RADIATOR CHECKING THE RADIATOR 1.Check: Radiator fins Obstruction → Clean. Apply compressed air to the rear of the radia- tor. Damage → Repair or replace. OTE: Straighten any flattened fins with a thin, flat- head screwdriver. 2.Check: Radiator hoses Cracks/damage →...

  • Page 263: Installing The Radiator

    COOL RADIATOR INSTALLING THE RADIATOR 1.Fill: Cooling system (with the specified amount of the recom- mended coolant) Refer to “CHANGING THE COOLANT” in CHAPTER 3. 2.Check: Cooling system Leaks → Repair or replace any faulty part. 6 - 4...

  • Page 264: Thermostat

    COOL THERMOSTAT THERMOSTAT Order Job name/Part name Q’ty Remarks Removing the thermostat Remove the parts in the order below. Front panel and front fender Refer to “SEAT, FENDERS AND FUEL TANK” in CHAPTER 3. Coolant Drain. Radiator Refer to “RADIATOR”. Radiator inlet hose Front fender bracket Thermostat inlet hose...
  • Page 265 COOL THERMOSTAT Order Job name/Part name Q’ty Remarks Disassembling the thermostat Remove the parts in the order listed. Thermostat cover O-ring Refer to “ASSEMBLING THE THERMO- STAT”. Thermostat Thermostat housing For assembly, reverse the disassembly procedure. 6 - 6...

  • Page 266: Checking The Thermostat

    COOL THERMOSTAT CHECKING THE THERMOSTAT 1.Check: Thermostat 1 Does not open at 69 ~ 73 °C (156.2 ~ 163.4 °F) → Replace. *********************************************** Checking steps: Suspend the thermostat in a container filled with water. Slowly heat the water. Place a thermometer in the water. While stirring the water, observe the thermo- stat and thermometer’s indicated tempera- ture.

  • Page 267: Water Pump

    COOL WATER PUMP WATER PUMP Order Job name/Part name Q’ty Remarks Removing the water pump Remove the parts in the order below. Coolant Drain. Radiator outlet hose Disconnect. Water pump outlet hose Water pump assembly O-ring Water jacket inlet housing O-ring For installation, reverse the removal pro- cedure.
  • Page 268 COOL WATER PUMP Order Job name/Part name Q’ty Remarks Disassembling the water pump Remove the parts in the order below. Water pump housing cover O-ring Circlip Impeller shaft gear Circlip Impeller Refer to “DISASSEMBLING/ASSEM- Impeller shaft BLING THE THERMOSTAT”. Rubber damper holder 6 - 9...
  • Page 269 COOL WATER PUMP Order Job name/Part name Q’ty Remarks Rubber damper Water pump seal Refer to “DISASSEMBLING/ASSEM- Oil seal BLING THE THERMOSTAT”. Bearing Water pump housing For assembly, reverse the disassembly procedure. 6 - 10...

  • Page 270: Disassembling The Water Pump

    COOL WATER PUMP DISASSEMBLING THE WATER PUMP 1.Remove: Impeller shaft 1 OTE: Tap out the impeller shaft from the impeller. 2.Remove: Rubber damper holder 1 Rubber damper 2 (from the impeller, with a thin, flathead screwdriver) OTE: Do not scratch the impeller. 3.Remove: Water pump seal 1 OTE:...

  • Page 271: Assembling The Water Pump

    COOL WATER PUMP 2.Check: Water pump seal Oil seal Water pump outlet pipe Cracks/damage/wear → Replace. Bearing Rough movement → Replace. ASSEMBLING THE WATER PUMP 1.Install: Oil seal 1 (into the water pump housing 2) OTE: Before installing the oil seal, apply tap water or coolant onto its outer surface.
  • Page 272 COOL WATER PUMP 4.Measure: Impeller shaft tilt Out of specification → Repeat steps (3) and (4). CAUTION: Make sure that the rubber damper and rub- ber damper holder are bottom with the impeller. Max. impeller shaft tilt: 0.15 mm (0.006 in) 1 Straightedge 2 Impeller 6 - 13...

  • Page 273: Chapter 7. Carburetion

    CARB CARBURETORS CARBURETION CARBURETORS Order Job name/Part name Q’ty Remarks Removing the carburetors Remove the parts in the order below. Seat/front fender/fuel tank/rubber cover Refer to “SEAT, FENDERS AND FUEL TANK” in CHAPTER 3. Air vent hose Float chamber breather hose Starter cable/starter plunger Throttle valve cover Throttle cable end...

  • Page 274: Carb

    CARB CARBURETORS Order Job name/Part name Q’ty Remarks Separating the carburetors Remove the parts in the order below. Drain hose Plate Connecting bolt/spacer Spring Hose joint Pipe Carburetor 2 Carburetor 1 For installation, reverse the separating procedure. 7 - 2...
  • Page 275 CARB CARBURETORS Order Job name/Part name Q’ty Remarks Disassembling the carburetor Remove the parts in the order below. Throttle stop screw Vacuum chamber cover Spring Jet needle holder Spring Jet needle set Piston valve Float chamber Drain screw Float Refer to “ASSEMBLING THE CARBURE- TOR”.
  • Page 276 CARB CARBURETORS Order Job name/Part name Q’ty Remarks Pilot jet Pilot screw set Refer to “DISASSEMBLING/ ASSEMBLING THE CARBURETOR”. OTE: Before disassembling the carburetor, make sure to note the number of times the pilot screw is turned out from the seated position to its set position.

  • Page 277: Disassembling The Carburetor

    CARB CARBURETORS DISASSEMBLING THE CARBURETOR OTE: Before disassembling the carburetor, make sure to note the number of times the pilot screw is turned out from the seated position to its set position. CHECKING THE CARBURETOR 1.Check: Carburetor body Float chamber Cracks/damage →...
  • Page 278 CARB CARBURETORS 4.Check: Piston valve 1 Scratches/wear/damage → Replace. Rubber diaphragm 2 Tears → Replace. 5.Check: Vacuum chamber cover 1 Spring 2 Cracks/damage → Replace. 6.Check: Jet needle 1 Main jet 2 Needle jet 3 Pilot air jet 4 Pilot jet 5 Pilot screw 6 Starter jet 7 Starter plunger 8...

  • Page 279: Assembling The Carburetor

    CARB CARBURETORS ASSEMBLING THE CARBURETOR CAUTION: Before reassembling, wash all of the parts in a clean petroleum based solvent. 1.Install: Pilot screw 1 OTE: Before assembling the carburetor, make sure to turn out the pilot screw the same number of times, as noted before disassembly, from the seated position to the set position.

  • Page 280: Adjusting The Fuel Level

    CARB CARBURETORS 3.Install: Carburetor 1 Carburetor 2 Pipe Hose joint Spring OTE: Install the throttle valve lever 1 onto carburetor 2 between the spring 2 and synchronizing screw 3. Make sure the throttle valves operate smoothly and that the synchronization is correct.
  • Page 281 CARB CARBURETORS Remove the carburetor. Inspect the valve seat and needle valve. If either is worn, replace them both. If both are fine, adjust the float level by bending the float tang 4 slightly. Install the carburetor. Recheck the fuel level. *********************************************** 7 - 9...

  • Page 282: Elec

    – ELEC ELECTRICAL COMPONENTS EB800000 ELECTRICAL ELECTRICAL COMPONENTS 1 Main switch 9 Starter relay G Rear brake switch 2 Front brake switch 0 Tail/brake light H Ignition coil 3 Indicator light A Rectifier/regulator I Headlight 4 Circuit breaker (fan) B CDI unit J Thermo switch 1 5 Park switch C Battery...

  • Page 283: Checking The Switch

    – ELEC CHECKING THE SWITCH CHECKING THE SWITCH CHECKING THE SWITCH Use a pocket tester to check the terminals for continuity. If the continuity is faulty at any point, replace the switch. Pocket tester: P/N. YU-03112, 90890-03112 OTE: Set the pocket tester to “0” before starting the test.

  • Page 284: Checking The Switch Continuity

    – ELEC CHECKING THE SWITCH CHECKING THE SWITCH CONTINUITY Refer to “CHECKING THE SWITCH” and check for continuity between lead terminals. Poor connection, no continuity → Correct or replace. The coupler locations are circled. 8 - 3...
  • Page 285 – ELEC CHECKING THE SWITCH 1 Lights switch 2 Engine stop switch 3 Start switch 4 Main switch 5 Front brake switch 6 Clutch switch 7 Park switch 8 Fuse 9 Reverse switch 0 Neutral switch A Rear brake switch 8 - 4...

  • Page 286: Ignition System

    – ELEC IGNITION SYSTEM EB802000 IGNITION SYSTEM CIRCUIT DIAGRAM 8 - 5...

  • Page 287: Troubleshooting

    – ELEC IGNITION SYSTEM EB802010 TROUBLESHOOTING IF THE IGNITION SYSTEM FAILS TO OPERATE (NO SPARK OR INTERMITTENT SPARK): Procedure Check: 1.Fuse 7.Engine stop switch 2.Battery 8.Main switch 3.Spark plug 9.Pickup coil resistance 4.Ignition spark gap 10.Charging/rotor rotation direction detection 5.Spark plug cap resistance coil resistance 6.Ignition coil resistance 11.Wiring connection (the entire ignition sys-...
  • Page 288 – ELEC IGNITION SYSTEM INCORRECT Spark plug gap: 0.8 ~ 0.9 mm (0.031 ~ 0.035 in) CORRECT Repair or replace the spark plug. For USA and CDN 4.Ignition spark gap Disconnect the spark plug cap from the spark plug. Connect the dynamic spark tester 1 as shown.
  • Page 289 – ELEC IGNITION SYSTEM 5.Spark plug cap resistance Remove the spark plug cap. Connect the pocket tester (Ω × 1k) to the spark plug cap. OUT OF SPECIFICATION Check that the spark plug cap has the specified resistance. Spark plug cap resistance: 10 kΩ...
  • Page 290 – ELEC IGNITION SYSTEM Connect the pocket tester (Ω × 1k) to the ignition coil. Tester (+) lead → Orange lead terminal Tester (–) lead → Spark plug lead Check that the secondary coil has the specified resistance. Secondary coil resistance: 6.32 ~ 9.48 kΩ...
  • Page 291 – ELEC IGNITION SYSTEM C0NTINUITY 10.Charging/rotor rotation direction detec- tion coil resistance Disconnect the AC magneto coupler from the wire harness. Connect the pocket tester (Ω × 100) to the charging/rotor rotation direction detection coil terminal. Tester (+) lead → Red terminal 1 Tester (–) lead →...

  • Page 292: Electric Starting System

    – ELEC ELECTRIC STARTING SYSTEM EB803000 ELECTRIC STARTING SYSTEM CIRCUIT DIAGRAM 8 - 11...

  • Page 293: Starting Circuit Operation

    – ELEC ELECTRIC STARTING SYSTEM STARTING CIRCUIT OPERATION The starting circuit on this model consists of the starter motor, starter relay, clutch switch, CDI unit and neutral switch. If the main switch is on and the engine stop switch is in the RUN position, the starter motor can be operated only if: The transmission is in neutral (the neutral...

  • Page 294: Troubleshooting

    – ELEC ELECTRIC STARTING SYSTEM EB803020 TROUBLESHOOTING IF THE STARTER MOTOR FAILS TO OPERATE: Procedure Check: 7.Start switch 1.Fuse 8.Neutral switch 2.Battery 9.Clutch switch 3.Starter motor 10.Wiring connection (the entire starting sys- 4.Starter relay tem) 5.Main switch 6.Engine stop switch OTE: Pocket tester: Remove the following part(s) before trouble-...
  • Page 295 – ELEC ELECTRIC STARTING SYSTEM C0NTINUITY WARNING 3.Starter motor A wire that is used as a jumper lead must Connect the battery positive terminal 1 have the equivalent capacity or more as and starter motor cable 2 using a jumper that of the battery lead, otherwise the lead 3 jumper lead may burn.
  • Page 296 – ELEC ELECTRIC STARTING SYSTEM C0NTINUITY INCORRECT 6.Engine stop switch Refer to “CHECKING THE SWITCH”. CORRECT Replace the handlebar switch (right). INCORRECT 7.Start switch Refer to “CHECKING THE SWITCH”. CORRECT Replace the handlebar switch (left). INCORRECT 8.Neutral switch Refer to “CHECKING THE SWITCH”. CORRECT Replace the neutral switch.

  • Page 297: Starter Motor

    – ELEC ELECTRIC STARTING SYSTEM STARTER MOTOR Order Job name/Part name Q’ty Remarks Removing the starter motor Remove the parts in the order below. Exhaust pipe Refer to “ENGINE REMOVAL”. Parking brake cable Disconnect. Starter motor lead Starter motor/O-ring Disassembling the starter motor Remove the parts in the order below.

  • Page 298: Checking The Starter Motor

    – ELEC ELECTRIC STARTING SYSTEM CHECKING THE STARTER MOTOR 1.Check: Commutator Dirty → Clean it with #600 grit sandpaper. 2.Measure: Commutator diameter a Out of specification → Replace the starter motor. Outside diameter: 28 mm (1.10 in) <Wear limit:> 27 mm (1.06 in) 3.Measure: Mica undercut b Out of specification →...

  • Page 299: Assembling The Starter Motor

    – ELEC ELECTRIC STARTING SYSTEM 5.Measure: Brush length a (each) Out of specification → Replace the brush. Brush length: 12.5 mm (0.49 in) <Wear limit:> 5 mm (0.20 in) 6.Measure: Brush spring force Fatigue/out of specification → Replace as a set.

  • Page 300: Charging System

    – ELEC CHARGING SYSTEM EB804000 CHARGING SYSTEM CIRCUIT DIAGRAM 1 AC magneto 2 Rectifier/regulator 4 Battery 5 Fuse 8 - 19...

  • Page 301: Troubleshooting

    – ELEC CHARGING SYSTEM EB804010 TROUBLESHOOTING IF THE BATTERY IS NOT CHARGED: Procedure Check: 1.Fuse 4.Charging coil resistance 2.Battery 5.Wiring connections 3.Charging voltage (the entire charging system) OTE: Pocket tester: Remove the following part(s) before trouble- P/N. YU-03112, 90890-03112 shooting: 1)Seat Use the following special tool(s) for trouble- shooting.
  • Page 302 – ELEC CHARGING SYSTEM Start the engine and accelerate to about 5,000 r/min. MEETS SPECIFICATION Charging voltage: 14 V at 5,000 r/min OUT OF SPECIFICATION The charging circuit is not faulty. EB804012 4.Charging coil resistance Disconnect the AC magneto coupler from the wire harness.

  • Page 303: Lighting System

    – ELEC LIGHTING SYSTEM EB805000 LIGHTING SYSTEM CIRCUIT DIAGRAM 3 Main switch 4 Battery 5 Fuse O Lights switch R Headlight S Tail/brake light 8 - 22...

  • Page 304: Troubleshooting

    – ELEC LIGHTING SYSTEM EB805010 TROUBLESHOOTING IF THE HEADLIGHT AND/OR TAIL/BRAKE LIGHT FAIL TO COME ON: Procedure Check: 4.Lights switch 1.Fuse 5.Wiring connections 2.Battery (the entire lighting system) 3.Main switch OTE: Pocket tester: Remove the following part(s) before trouble- P/N. YU-03112, 90890-03112 shooting: 1)Seat 2)Front fender...
  • Page 305 – ELEC LIGHTING SYSTEM C0NTINUITY INCORRECT 3.Main switch Refer to “CHECKING THE SWITCH”. CORRECT Replace the main switch. INCORRECT 4.Lights switch Refer to “CHECKING THE SWITCH”. Lights switch is faulty, replace the handlebar CORRECT switch (left). EB805013 5.Wiring connection POOR CONNECTION Check the connections of the entire lighting system.

  • Page 306: Checking The Lighting System

    – ELEC LIGHTING SYSTEM EB805020 CHECKING THE LIGHTING SYSTEM 1.If the headlights fail to come on: NO CONTINUITY 1.Bulb and bulb socket Check the bulb and bulb socket for continu- ity. Replace the bulb and/or bulb socket. CONTINUITY 2.Voltage Connect the pocket tester (DC 20V) to the headlight couplers.
  • Page 307 – ELEC LIGHTING SYSTEM EB805021 2.If the tail/brake light fails to come on: NO CONTINUITY 1.Bulb and bulb socket Check the bulb and bulb socket for continu- ity. Replace the bulb and/or bulb socket. CONTINUITY 2.Voltage Connect the pocket tester (20 V) to the bulb socket coupler.

  • Page 308: Signal System

    – ELEC SIGNAL SYSTEM EB806000 SIGNAL SYSTEM CIRCUIT DIAGRAM 8 - 27...

  • Page 309: Troubleshooting

    – ELEC SIGNAL SYSTEM EB806010 TROUBLESHOOTING IF THE TAIL/BRAKE LIGHT AND/OR INDICATOR LIGHT FAILS TO COME ON: Procedure Check: 1.Fuse 2.Battery 3.Main switch 4.Wiring connections (the entire signal system) OTE: Pocket tester: Remove the following part(s) before trouble- P/N. YU-03112, 90890-03112 shooting: 1)Seat 2)Front fender...
  • Page 310 – ELEC SIGNAL SYSTEM C0NTINUITY INCORRECT 3.Main switch Refer to “CHECKING THE SWITCH”. CORRECT Replace the main switch. EB806011 POOR CONNECTION 4.Wiring connections Check the connections of the entire signal system. Refer to “CIRCUIT DIAGRAM”. Properly connect the signal system. CORRECT Check the condition of each of the signal sys- tem’s circuits.

  • Page 311: Checking The Signal System

    – ELEC SIGNAL SYSTEM CHECKING THE SIGNAL SYSTEM 1.If the tail/brake light fails to come on: 1.Bulb and bulb socket NO CONTINUITY Check the bulb and bulb socket for continu- ity. CONTINUITY Replace the bulb and/or bulb socket. NO CONTINUITY 2.Brake switches Refer to “CHECKING THE SWITCH”.
  • Page 312 – ELEC SIGNAL SYSTEM EB806024 2.If the neutral indicator light fails to come on: 1.Bulb and bulb socket NO CONTINUITY Check the bulb and bulb socket for continu- ity. Replace the bulb and/or bulb socket. CONTINUITY NO CONTINUITY 2.Neutral switch Refer to “CHECKING THE SWITCH”.
  • Page 313 – ELEC SIGNAL SYSTEM 3.If the reverse indicator light fails to come on: NO CONTINUITY 1.Bulb and bulb socket Check the bulb and bulb socket for continu- ity. Replace the bulb and/or bulb socket. CONTINUITY NO CONTINUITY 2.Reverse switch Refer to “CHECKING THE SWITCH”. CONTINUITY Replace the reverse switch.
  • Page 314 – ELEC SIGNAL SYSTEM 4.If the coolant temperature warning light does not come on when the start switch is pushed on, or if the coolant temperature warning light does not come on when the temperature is high (more than 117 ~ 123 °C (242.6 ~ 253.4 °F)): NO CONTINUITY 1.Bulb and bulb socket Check the bulb and bulb socket for continu-...
  • Page 315 – ELEC SIGNAL SYSTEM C0NTINUITY 3.Voltage Connect the pocket tester (DC 20V) to the bulb socket coupler. Tester (+) lead → Red/Black terminal 1 Tester (–) lead → White/Blue terminal 2 OUT OF SPECIFICATION Turn the main switch to “ON”. Check the voltage (12 V).
  • Page 316 – ELEC SIGNAL SYSTEM C0NTINUITY INCORRECT 5.Start switch Refer to “CHECKING THE SWITCH”. CORRECT Replace the handlebar switch (left). This circuit is not faulty. 8 - 35...

  • Page 317: Cooling System

    – ELEC COOLING SYSTEM COOLING SYSTEM CIRCUIT DIAGRAM 8 - 36...
  • Page 318 – ELEC COOLING SYSTEM TROUBLESHOOTING IF THE FAN MOTOR DOES NOT MOVE: Procedure Check: 1.Fuse 6.Thermo switch 1 7.Wiring connection 2.Battery 3.Main switch (the entire cooling system) 4.Fan motor 5.Circuit breaker (fan motor) OTE: Pocket tester: Remove the following part(s) before trouble- P/N.
  • Page 319 – ELEC COOLING SYSTEM C0NTINUITY 4.Fan motor Disconnect the fan motor coupler. Connect the battery (12 V) as shown. Battery (+) lead → Blue terminal 1 Battery (–) lead → Black terminal 2 DOES NOT TURN Replace the fan motor. Check the operation of the fan motor.
  • Page 320 – ELEC COOLING SYSTEM C0NTINUITY 6.Thermo switch 1 Remove the thermo switch from the radia- tor. Connect the pocket tester (Ω × 10) to the thermo switch 1. Immerse the thermo switch in coolant 2. Check the thermo switch for continuity. While heating the coolant use a thermome- ter 3 to record the temperatures.
  • Page 321 – ELEC COOLING SYSTEM C0NTINUITY EB803028 POOR CONNECTION 7.Wiring connection Check the connections of the entire starting system. Refer to “CIRCUIT DIAGRAM”. Properly connect the cooling system. CORRECT This circuit is not faulty. 8 - 40...

  • Page 322: Trbl Shtg

    TRBL STARTING FAILURE/HARD STARTING SHTG 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 manual for inspection, adjustment and replacement of parts. STARTING FAILURE/HARD STARTING FUEL SYSTEM Fuel tank...

  • Page 323: Compression System

    TRBL STARTING FAILURE/HARD STARTING/POOR IDLE SPEED SHTG PERFORMANCE/POOR MEDIUM AND HIGH-SPEED PERFORMANCE COMPRESSION SYSTEM Cylinder and cylinder head Piston and piston rings Loose spark plug Improperly installed piston ring Loose cylinder head or cylinder Worn, fatigued or broken piston ring Broken cylinder head gasket Seized piston ring Broken cylinder gasket...

  • Page 324: Faulty Gear Shifting

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

  • Page 325: Overheating

    OVERHEATING/OVER COOLING/ TRBL FAULTY BRAKE SHTG OVERHEATING OVERHEATING Ignition system Engine oil Improper spark plug gap Improper oil level Improper spark plug heat range Improper oil viscosity Faulty CDI unit Inferior oil quality Fuel system Brake Improper carburetor main jet Brake drag (improper setting) Cooling system...

  • Page 326: Shock Absorber Malfunction

    SHOCK ABSORBER MALFUNCTION/ TRBL UNSTABLE HANDLING/LIGHTING SYSTEM SHTG SHOCK ABSORBER MALFUNCTION MALFUNCTION Bent or damaged damper rod Damaged oil seal lip Fatigued shock absorber spring UNSTABLE HANDLING UNSTABLE HANDLING Handlebar Wheels Improperly installed or bent Deformed wheel Steering Loose bearing Incorrect toe-in Bent or loose wheel axle Bent steering stem...
  • Page 327 YAMAHA MOTOR CO., LTD. 2500 SHINGAI IWATA SHIZUOKA JAPAN PRINTED IN U.S.A.

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