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Yamaha YZ85W1 Service Manual

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2007
YZ85W1
YZ85(W)
YZ85LW(W)
SERVICE MANUAL
5PA-28197-E0

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  • Page 1 2007 YZ85W1 YZ85(W) YZ85LW(W) SERVICE MANUAL 5PA-28197-E0...
  • Page 2 EAS00000 YZ85W1 / YZ85 (W) / YZ85LW (W) SERVICE MANUAL ©2006 by Yamaha Motor Co., Ltd. First edition, April 2006 All rights reserved. Any reproduction or unauthorized use without the written permission of Yamaha Motor Co., Ltd. is expressly prohibited.
  • Page 3 EAS00002 NOTICE This manual was produced by the Yamaha Motor Company, Ltd. primarily for use by Yamaha deal- ers and their qualified mechanics. It is not possible to include all the knowledge of a mechanic in one manual. Therefore, anyone who uses this book to perform maintenance and repairs on Yamaha vehicles should have a basic understanding of mechanics and the techniques to repair these types of vehicles.
  • Page 4 EAS00007 HOW TO USE THIS MANUAL This manual is intended as a handy, easy-to-read reference book for the mechanic. Comprehensive explanations of all installation, removal, disassembly, assembly, repair and check procedures are laid out with the individual steps in sequential order. The manual is divided into chapters.
  • Page 5 EAS00008 SYMBOLS The following symbols are not relevant to every vehicle. Symbols indicate the subject of each chapter. General information Specifications Periodic checks and adjustments Chassis Engine Cooling system Carburetor(s) Electrical system Tuning Troubleshooting Symbols indicate the following. Serviceable with engine mounted Filling fluid Lubricant Special tool...
  • Page 6 EAS00010 TABLE OF CONTENTS GENERAL INFORMATION INFO SPECIFICATIONS SPEC PERIODIC CHECKS AND ADJUSTMENTS CHASSIS CHAS ENGINE COOLING SYSTEM COOL CARBURETOR CARB ELECTRICAL SYSTEM ELEC TUNING TROUBLESHOOTING TRBL SHTG...

  • Page 7: Table Of Contents

    INFO CHAPTER 1 GENERAL INFORMATION VEHICLE IDENTIFICATION ........1-1 VEHICLE IDENTIFICATION NUMBER .

  • Page 8: General Information

    VEHICLE IDENTIFICATION INFO EAS00014 GENERAL INFORMATION VEHICLE IDENTIFICATION EAS00017 VEHICLE IDENTIFICATION NUMBER The vehicle identification number stamped into the right side of the steering head pipe. EAS00018 MODEL LABEL The model label is affixed to the frame. This information will be needed to order spare parts.

  • Page 9: Important Information

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

  • Page 10: Lock Washers / Plates And Cotter Pins

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

  • Page 11: Fuel And Engine Mixing Oil

    FUEL AND ENGINE MIXING OIL INFO FUEL AND ENGINE MIXING OIL Mix oil with the gas at the ratio specified below. Always use fresh, name-brand gasoline, and mix the oil and gas the day of the race. Do not use premix that is more than a few hours old. Recommended fuel Premium unleaded gasoline only with a research octane...

  • Page 12: Checking The Connections

    CHECKING THE CONNECTIONS INFO EAS00026 CHECKING THE CONNECTIONS Check the leads, couplers, and connectors for stains, rust, moisture, etc. 1. Disconnect: • lead • coupler • connector 2. Check: • lead • coupler • connector Moisture → Dry with an air blower. Rust / stains →...

  • Page 13: Special Tools

    SPECIAL TOOLS INFO EAS00027 SPECIAL TOOLS The following special tools are necessary for complete and accurate tune-up and assembly. Use only the appropriate special tools as this will help prevent damage caused by the use of inappropri- ate tools or improvised techniques. Special tools, part numbers or both may differ depending on the country.
  • Page 14 SPECIAL TOOLS INFO Tool No. Tool name / Function Illustration Radiator cap tester Radiator cap tester 90890-01325 Radiator cap tester adapter YU-24460-01 Radiator cap tester adapter These tools are used for checking the cooling 90890-01352 system. YU-33984 Steering nut wrench 90890-01403 YU-33975 This tool is used when tighten the steering...
  • Page 15 Tool name / Function Illustration Dynamic spark tester Ignition checker 90890-06754 YM-34487 This instrument is necessary for checking the ignition system components. Yamaha bond No.1215 ® (Three Bond No.1215 90890-85505 This sealant (Bond) is used for crankcase mating surface, etc.
  • Page 16 SPEC CHAPTER 2 SPECIFICATIONS GENERAL SPECIFICATIONS ....... . 2-1 ENGINE SPECIFICATIONS ........2-2 CHASSIS SPECIFICATIONS .

  • Page 17: Specifications

    SPEC GENERAL SPECIFICATIONS SPECIFICATIONS GENERAL SPECIFICATIONS Item Standard Limit Model code YZ85 5PAG (EUR, CAN), 5PAH (AUS,NZL) • • • YZ85LW 5SHG (EUR), 5SHH (AUS,NZL) • • • Dimensions Overall length 1,818 mm (71.6 in) (YZ85) • • • 1,903 mm (74.9 in) (YZ85LW) •...

  • Page 18: Engine Specifications

    SPEC ENGINE SPECIFICATIONS ENGINE SPECIFICATIONS Item Standard Limit Engine Engine type Liquid cooled 2-stroke, gasoline • • • Displacement 84.7 cm (5.17 cu.in) • • • Cylinder arrangement Single cylinder, forward inclined • • • Bore × stroke 47.5 × 47.8 mm (1.870 × 1.882 in) •...
  • Page 19 SPEC ENGINE SPECIFICATIONS Item Standard Limit Cylinder Bore 47.500 ~ 47.514 mm (1.8701 ~ 1.8706 in) 47.6 mm (1.874 in) Max. taper limit • • • 0.05 mm (0.0020 in) Max. out-of-round • • • 0.01 mm (0.0004 in) Piston Piston-to-cylinder clearance 0.040 ~ 0.045 mm (0.0016 ~ 0.0018 in) 0.1 mm...
  • Page 20 SPEC ENGINE SPECIFICATIONS Item Standard Limit Crankshaft Crank width “A” 44.90 ~ 44.95 mm (1.768 ~ 1.770 in) • • • Runout limit “C” 0.03 mm (0.0012 in) 0.05 mm (0.002 in) (YZ85) 0.08 mm (0.003 in) (YZ85LW) Big end side clearance “D” 0.20 ~ 0.70 mm (0.008 ~ 0.028 in) •...
  • Page 21 SPEC ENGINE SPECIFICATIONS Item Standard Limit Transmission Transmission type Constant mesh, 6-speed • • • Primary reduction system Spur gear • • • Primary reduction ratio 65 / 18 (3.611) • • • Secondary reduction system Chain drive • • • Secondary reduction ratio 47 / 14 (3.357) (YZ85 for EUR, CAN) •...
  • Page 22 SPEC ENGINE SPECIFICATIONS Item Standard Limit Reed valve Thickness “T” 0.42 mm (0.017 in) • • • Valve stopper height 7.4 ~ 7.8 mm (0.291 ~ 0.307 in) • • • Valve bending limit 0.2 mm (0.008 in)

  • Page 23: Chassis Specifications

    SPEC CHASSIS SPECIFICATIONS CHASSIS SPECIFICATIONS Item Standard Limit Frame Frame type Semi double cradle • • • Material Steel • • • Caster angle 26.3° (YZ85) • • • 26.9° (YZ85LW) • • • Trail 88.0 mm (3.46 in) (YZ85) •...
  • Page 24 SPEC CHASSIS SPECIFICATIONS Item Standard Limit Front tire Tire type Tube • • • Size 70 / 100-17 40M (YZ85) • • • 70 / 100-19 42M (YZ85LW) • • • Model (manufacturer) D739FA (DUNLOP) (YZ85 for EUR, CAN) • • • D756F (DUNLOP)( YZ85 for AUS, NZL) •...
  • Page 25 SPEC CHASSIS SPECIFICATIONS Item Standard Limit Steering Steering bearing type Taper roller bearing • • • Lock to lock angle (left) 45° • • • Lock to lock angle (right) 45° • • • Front suspension Suspension type Telescopic fork •...
  • Page 26 SPEC CHASSIS SPECIFICATIONS Item Standard Limit Rear suspension Suspension type Swingarm (link type monocross • • • suspension) Rear shock absorber assembly type Coil spring / gas, oil damper • • • Rear shock absorber assembly travel 102 mm (4.02 in) •...

  • Page 27: Electrical Specifications

    Advancer type Digital • • • C.D.I. Magneto model (manufacturer) 5PA-01 (YAMAHA) • • • 248 ~ 372 Ω at 20 °C (68 °F) (W / L-W / R) Pickup coil resistance (color) • • • 720 ~ 1,080 Ω at 20 °C (68 °F) (G / W-B / R) • • •...

  • Page 28: Conversion Table

    CONVERSION TABLE / SPEC GENERAL TIGHTENING TORQUE SPECIFICATIONS EAS00028 EAS00030 CONVERSION TABLE GENERAL TIGHTENING TORQUE All specification data in this manual are listed SPECIFICATIONS in SI and METRIC UNITS. This chart specifies tightening torques for Use this table to convert METRIC unit data to standard fasteners with a standard ISO thread IMPERIAL unit data.

  • Page 29: Tightening Torques

    SPEC TIGHTENING TORQUES TIGHTENING TORQUES ENGINE TIGHTENING TORQUES Tightening torque Thread Item Fastener Q’ty Remarks size m•kg ft•lb Spark plug — Cylinder head Stud bolt Cylinder Studbolt Water pump impeller — Coolant drain bolt Bolt Water pump housing Bolt Radiator hose clamp Clamp Air filter element Bolt...

  • Page 30: Chassis Tightening Torques

    SPEC TIGHTENING TORQUES CHASSIS TIGHTENING TORQUES Tightening torque Thread Item Fastener Q’ty Remarks size m•kg ft•lb Upper bracket and outer tube Bolt Lower bracket and outer tube Bolt Upper bracket and steering stem 12.5 Handlebar holder and upper bracket Bolt Steering stem and steering ring nut See NOTE.
  • Page 31 SPEC TIGHTENING TORQUES Tightening torque Thread Item Fastener Q’ty Remarks size m•kg ft•lb Relay arm and connecting rod Connecting rod and swingarm Rear shock absorber and frame Rear shock absorber and relay arm Bolt Rear frame (upper) Bolt Rear frame (lower) Bolt Swingarm and brake hose holder Screw...

  • Page 32: Lubrication Points And Lubricant Types

    Push lever (lower) Transmission wheel gears inner surface Transmission pinion gears Shift forks and shift fork guide bers Shift shaft Shift dram Crankcase mating surface Yamaha bond No.1215 EAS00032 CHASSIS Lubrication point Lubricant Steeling bearings and bearing race (upper and lower)

  • Page 33: Cable Routing

    SPEC CABLE ROUTING EAS00035 CABLE ROUTING Cable guide Radiator breather hose Brake hose Clutch cable Throttle cable Spark plug lead Fuel tank breather hose Radiator hose Engine stop switch lead Brake hose holder Ground lead Ignition coil Primary coil lead (orange color) Damper Clamp Air vent hoses...
  • Page 34 SPEC CABLE ROUTING Pass the fuel tank breather hose between the han- Securely install the spark plug cap to the spark dlebar and tension bar, then insert its end into the plug. Route the spark plug lead by the inner side of the vehicle than the radiator hose and throttle hole of the steering stem.
  • Page 35 SPEC CABLE ROUTING Sub-wire harness Route the clutch cable in front of the throttle cable. CDI unit Pass the transmission oil breather hose through the hose guide. Ignition coil Clutch cable Clamp it between these parts. Cable guide Clamp it using the white PVC tape as a guide. Transmission oil breather hose Pass the sub-wire harness on the left side of the CDI unit band...
  • Page 36 SPEC CABLE ROUTING Install the clip pointing the clamp section to the rear side. Touch the brake pipe to the stopper. When installing the brake hose, install it so that the bend section of the brake hose attachment is pointed in the direction as shown in the illustration. 2-20...
  • Page 37 SPEC CABLE ROUTING Master cylinder This is the number plate attaching section. The Throttle cable clutch cable and throttle cable shall be routed crossways above the number plate attaching sec- Clutch cable Clamp tion. At this time, make sure to route the clutch Engine stop switch lead cable to the front side of the throttle cable.
  • Page 38 CHAPTER 3 PERIODIC CHECKS AND ADJUSTMENTS INTRODUCTION ......... . . 3-1 PERIODIC MAINTENANCE AND LUBRICATION INTERVALS .

  • Page 39: Periodic Checks And Adjustments

    PERIODIC MAINTENANCE AND LUBRICATION INTERVALS NOTE: • From the seventh race, repeat the maintenance intervals starting from “Every race”. • Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools, data and technical skills. After...
  • Page 40 PERIODIC MAINTENANCE AND LUBRICATION INTERVALS After Every Every Every ITEM ROUTINE break-in race third race fifth race required √ √ • Check coolant level and for leakage. √ • Check hoses for cracks or damage. Cooling system √ • Check radiator cap spring operation. √...

  • Page 41: Seat, Side Covers And Fuel Tank

    SEAT, SIDE COVERS AND FUEL TANK EAS00042 SEAT, SIDE COVERS AND FUEL TANK 7 Nm (0.7 m•kg, 5.1 ft•lb) 7 Nm (0.7 m•kg, 5.1 ft•lb) 7 Nm (0.7 m•kg, 5.1 ft•lb) 7 Nm (0.7 m•kg, 5.1 ft•lb) 4 Nm (0.4 m•kg, 2.9 ft•lb) 4 Nm (0.4 m•kg, 2.9 ft•lb) Order Job / Part...
  • Page 42 SEAT, SIDE COVERS AND FUEL TANK 7 Nm (0.7 m•kg, 5.1 ft•lb) 7 Nm (0.7 m•kg, 5.1 ft•lb) 7 Nm (0.7 m•kg, 5.1 ft•lb) 7 Nm (0.7 m•kg, 5.1 ft•lb) 4 Nm (0.4 m•kg, 2.9 ft•lb) 4 Nm (0.4 m•kg, 2.9 ft•lb) Order Job / Part Q’ty...

  • Page 43: Engine

    ADJUSTING THE PILOT AIR SCREW / ADJUSTING THE ENGINE IDLING SPEED ENGINE ADJUSTING THE PILOT AIR SCREW 1. Adjust: • pilot air screw NOTE: NOTE: To optimize the fuel flow at a smaller throttle opening, each vehicles pilot air screw has been individually set at the factory.

  • Page 44: Adjusting The Throttle Cable Free Play

    ADJUSTING THE THROTTLE CABLE FREE PLAY EAS00058 ADJUSTING THE THROTTLE CABLE FREE PLAY NOTE: NOTE: Prior to adjusting the throttle cable free play, the engine idling speed should be adjusted. 1. Check: • throttle cable free play Out of specification → Adjust. Throttle cable free play (at the flange of the throttle grip) 3.0 ~ 5.0 mm (0.12 ~ 0.20 in)

  • Page 45: Checking The Spark Plug

    CHECKING THE SPARK PLUG EAS00060 CHECKING THE SPARK PLUG 1. Disconnect: • spark plug cap 2. Remove: • spark plug CAUTION: Before removing the spark plug, blow away any dirt accumulated in the spark plug well with compressed air to prevent it from fall- ing into the cylinder.

  • Page 46: Checking The Ignition Timing

    CHECKING THE IGNITION TIMING EAS00062 CHECKING THE IGNITION TIMING 1. Remove: • air scoop • spark plug • left crankcase cover 2. Attach: • dial gauge • dial gauge stand Dial gauge and stand 90890-01252, YU-3097 Stand YU-1256 3. Adjust: •...

  • Page 47: Changing The Transmission Oil

    CHECKING THE IGNITION TIMING / CHANGING THE TRANSMISSION OIL Screw (stator) 8 Nm (0.8 m•kg, 5.8 ft•lb) 6. Check: • ignition timing Re-check the ignition timing. EAS00074 CHANGING THE TRANSMISSION OIL 1. Start the engine, warm it up for several min- utes, and then turn it off.

  • Page 48: Adjusting The Clutch Cable Free Play

    ADJUSTING THE CLUTCH CABLE FREE PLAY / CLEANING THE AIR FILTER ELEMENT EAS00081 ADJUSTING THE CLUTCH CABLE FREE PLAY 1. Check: • clutch cable free play Out of specification → Adjust. Clutch cable free play (at the end of the clutch lever) 10.0 ~ 15.0 mm (0.39 ~ 0.59 in) 2.
  • Page 49 CLEANING THE AIR FILTER ELEMENT • fitting bolt • washer • air filter guide • air filter element CAUTION: Never operate the engine without the air fil- ter element installed. Unfiltered air will cause rapid wear of engine parts and may damage the engine.

  • Page 50: Checking The Carburetor Joint

    CLEANING THE AIR FILTER ELEMENT / CHECKING THE CARBURETOR JOINT / CHECKING THE HOSES 7. Apply: • lithium-soap-base grease On the matching surface on air filter ele- ment. 8. Install: • air filter element • washer • fitting bolt 2 Nm (0.2 m•kg, 1.4 ft•lb) NOTE: NOTE: •...

  • Page 51: Checking The Crankcase Breather Hose

    CHECKING THE CRANKCASE BREATHER HOSE / CHECKING THE EXHAUST SYSTEM EAS00098 CHECKING THE CRANKCASE BREATHER HOSE 1. Check: • crankcase breather hose Cracks / damage → Replace. Loose connection → Connect properly. CAUTION: Make sure the crankcase breather hose is routed correctly.

  • Page 52: Checking The Coolant Level

    CHECKING THE COOLANT LEVEL EAS00102 CHECKING THE COOLANT LEVEL 1. Stand the vehicle on a level surface. NOTE: NOTE: • Place the vehicle on a suitable stand. • Make sure the vehicle is upright. 2. Remove: • radiator cap CAUTION: A hot radiator is under pressure.

  • Page 53: Checking The Cooling System

    CHECKING THE COOLING SYSTEM / CHANGING THE COOLANT EAS00104 CHECKING THE COOLING SYSTEM 1. Remove: • air scoop Refer to “SEAT, SIDE COVERS AND FUEL TANK”. 2. Check: • radiator • radiator hose joint • radiator hose Cracks / damage → Replace. Refer to “COOLING SYSTEM”...
  • Page 54 CHANGING THE COOLANT 5. Fill: • coolant (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 0.54 L (0.48 Imp qt, 0.57 US qt) Handling notes for coolant Coolant is potentially harmful and should be handled with special care.

  • Page 55: Chassis

    CHANGING THE COOLANT / ADJUSTING THE FRONT BRAKE 8. Check: • coolant level Refer to “CHECKING THE COOLANT LEVEL”. NOTE: NOTE: Before checking the coolant level, wait a few minutes until the coolant has settled. EAS00106 CHASSIS ADJUSTING THE FRONT BRAKE 1.

  • Page 56: Adjusting The Rear Brake

    ADJUSTING THE REAR BRAKE EAS00111 ADJUSTING THE REAR BRAKE 1. Check: • brake pedal height Out of specification → Adjust. Brake pedal height 4.0 ~ 10.0 mm (0.16 ~ 0.39 in) 2. Adjust: • brake pedal height a. Loosen the locknut b.

  • Page 57: Checking The Brake Fluid Level

    CHECKING THE BRAKE FLUID LEVEL EAS00115 CHECKING THE BRAKE FLUID LEVEL 1. Stand the vehicle on a level surface. NOTE: NOTE: • Place the vehicle on a suitable stand. • Make sure the vehicle is upright. 2. Check: • brake fluid level →...

  • Page 58: Checking The Front And Rear Brake Pads

    CHECKING THE FRONT AND REAR BRAKE PADS / CHECKING THE FRONT AND REAR BRAKE HOSES EAS00118 CHECKING THE FRONT AND REAR BRAKE PADS The following procedure applies to all of the brake pads. 1. Check: • front brake pad • rear brake pad Wear indicators almost touch the brake disc →...

  • Page 59: Bleeding The Hydraulic Brake System

    BLEEDING THE HYDRAULIC BRAKE SYSTEM EAS00135 BLEEDING THE HYDRAULIC BRAKE SYSTEM WARNING Bleed the hydraulic brake system when- ever: • the system is disassembled. • a brake hose is loosened, disconnected or replaced. • the brake fluid level is very low. •...

  • Page 60: Adjusting The Shift Pedal

    BLEEDING THE HYDRAULIC BRAKE SYSTEM / ADJUSTING THE SHIFT PEDAL / ADJUSTING THE DRIVE CHAIN SLACK i. Repeat steps (e) to (h) until all of the air bubbles have disappeared from the brake fluid in the plastic hose. j. Tighten the bleed screw to specification. Bleed screw 6 Nm (0.6 m•kg, 4.3 ft•lb) k.
  • Page 61 ADJUSTING THE DRIVE CHAIN SLACK 1. Elevate the rear wheel by placing the suit- able stand under the engine. WARNING Securely support the vehicle so that there is no danger of it falling over. 2. Move the rear wheel several times and find the tightest position of drive chain.

  • Page 62: Lubricating The Drive Chain

    LUBRICATING THE DRIVE CHAIN / CHECKING AND ADJUSTING THE STEERING HEAD EAS00143 LUBRICATING THE DRIVE CHAIN The drive chain consists of many interacting parts. If the drive chain is not maintained prop- erly, it will wear out quickly. Therefore, the drive chain should be serviced, especially when the vehicle is used in dusty areas.

  • Page 63: Checking The Front Fork

    CHECKING AND ADJUSTING THE STEERING HEAD / CHECKING THE FRONT FORK a. Remove the steering ring nut using the steering nut wrench b. Tighten the steering ring nut with a steering nut wrench NOTE: NOTE: • Set the torque wrench at a right angle to the steering nut wrench.

  • Page 64: Adjusting The Front Fork Legs

    CHECKING THE FRONT FORK / ADJUSTING THE FRONT FORK LEGS 2. Check: • inner tube Damage / scratches → Replace. • oil seal Oil leakage → Replace. 3. Hold the vehicle upright and apply the front brake. 4. Check: • front fork operation Push down hard on the handlebar several times and check if the front fork rebounds smoothly.
  • Page 65 ADJUSTING THE FRONT FORK LEGS 1. Adjust: • rebound damping a. Turn the adjusting screw in direction Rebound damping is Direction increased (suspension is harder). Rebound damping is Direction decreased (suspension is softer). Adjusting positions Minimum: 20 clicks in direction Standard: 7 clicks in direction Maximum: 1 clicks in direction * with the adjusting screw fully turned-in...

  • Page 66: Adjusting The Rear Shock Absorber Assembly

    ADJUSTING THE REAR SHOCK ABSORBER ASSEMBLY EAS00159 ADJUSTING THE REAR SHOCK ABSORBER ASSEMBLY WARNING Securely support the vehicle so that there is no danger of it falling over. Spring preload CAUTION: Never go beyond the maximum or minimum adjustment positions. 1.
  • Page 67 ADJUSTING THE REAR SHOCK ABSORBER ASSEMBLY Rebound damping CAUTION: Never go beyond the maximum or minimum adjustment positions. 1. Adjust: • rebound damping a. Turn the adjusting screw in direction Rebound damping is Direction increased (suspension is harder). Rebound damping is Direction decreased (suspension is softer).

  • Page 68: Checking The Tires

    ADJUSTING THE REAR SHOCK ABSORBER ASSEMBLY / CHECKING THE TIRES NOTE: NOTE: This is the position which is back by the spe- cific number of clicks from the fully turned-in position. (Which align the punch mark the adjuster with the punch mark on the bracket.) Adjusting positions...
  • Page 69 No guaran- tee concerning handling characteristics can be given if a tire combination other than one approved by Yamaha is used on this vehicle. Front tire YZ85:...

  • Page 70: Checking And Tightening The Spokes

    CHECKING THE TIRES / CHECKING AND TIGHTENING THE SPOKES / LUBRICATING THE LEVERS AND PEDALS / LUBRICATING THE REAR SUSPENSION WARNING New tires have a relatively low grip on the road surface until they have been slightly worn. NOTE: NOTE: Align the mark with the valve installation point.
  • Page 71 CHAS CHAPTER 4 CHASSIS FRONT WHEEL AND BRAKE DISC ......4-1 REMOVING THE FRONT WHEEL ......4-3 CHECKING THE FRONT WHEEL.
  • Page 72 CHAS HANDLEBAR ..........4-55 REMOVING THE HANDLEBAR .

  • Page 73: Front Wheel And Brake Disc

    CHAS FRONT WHEEL AND BRAKE DISC EAS00512 CHASSIS FRONT WHEEL AND BRAKE DISC 70 Nm (7.0 m•kg, 50 ft•lb) 12 Nm (1.2 m•kg, 8.7 ft•lb) Order Job / Part Q’ty Remarks Removing the front wheel and brake Remove the parts in the order listed. disc NOTE: NOTE:...
  • Page 74 CHAS FRONT WHEEL AND BRAKE DISC Order Job / Part Q’ty Remarks Disassembling the front wheel Disassemble the parts in the order listed. Oil seal Wheel bearing Collar For assembly, reverse the disassembly procedure.

  • Page 75: Removing The Front Wheel

    CHAS FRONT WHEEL AND BRAKE DISC EAS00519 REMOVING THE FRONT WHEEL 1. Stand the vehicle on a level surface. WARNING Securely support the vehicle so that there is no danger of it falling over. NOTE: NOTE: Place the vehicle on a suitable stand so that the front wheel is elevated.
  • Page 76 CHAS FRONT WHEEL AND BRAKE DISC 2. Check: • tire • front wheel Damage / wear → Replace. Refer to “CHECKING THE TIRES” and “CHECKING THE WHEELS” in chapter 3. 3. Check: • spokes Refer to “CHECKING AND TIGHTENING THE SPOKES” in chapter 3. NOTE: NOTE: After tightening the spokes, measure the front...
  • Page 77 CHAS FRONT WHEEL AND BRAKE DISC c. Remove the wheel bearings with a gen- eral bearing puller d. Install the new wheel bearings and oil seals in the reverse order of disassembly. CAUTION: Do not contact the wheel bearing inner race or balls .

  • Page 78: Checking The Brake Discs

    CHAS FRONT WHEEL AND BRAKE DISC EAS00531 CHECKING THE BRAKE DISCS The following procedure applies to all of the brake discs. 1. Check: • brake discs Damage / galling → Replace. 2. Measure: • brake disc deflection Out of specification → Correct the brake disc deflection or replace the brake disc.

  • Page 79: Installing The Front Wheel

    CHAS FRONT WHEEL AND BRAKE DISC Brake disc bolt 12 Nm (1.2 m•kg, 8.7 ft•lb) ® LOCTITE d. Measure the brake disc deflection. e. If out of specification, repeat the adjustment steps until the brake disc deflection is within specification. f.

  • Page 80: Rear Wheel And Brake Disc

    CHAS REAR WHEEL AND BRAKE DISC AS00551 REAR WHEEL AND BRAKE DISC REAR WHEEL 16 Nm (1.6 m•kg, 11 ft•lb) 16 Nm (1.6 m•kg, 11 ft•lb) 90 Nm (9.0 m•kg, 65 ft•lb) Order Job / Part Q’ty Remarks Removing the rear wheel Remove the parts in the order listed.
  • Page 81 CHAS REAR WHEEL AND BRAKE DISC 16 Nm (1.6 m•kg, 11 ft•lb) 16 Nm (1.6 m•kg, 11 ft•lb) 90 Nm (9.0 m•kg, 65 ft•lb) Order Job / Part Q’ty Remarks Collar For installation, reverse the removal procedure.

  • Page 82: Rear Brake Disc And Rear Wheel Sprocket

    CHAS REAR WHEEL AND BRAKE DISC EAS00560 REAR BRAKE DISC AND REAR WHEEL SPROCKET 12 Nm (1.2 m•kg, 8.7 ft•lb) 42 Nm (4.2 m•kg, 30 ft•lb) Order Job / Part Q’ty Remarks Removing the rear brake disc and Remove the parts in the order listed. rear wheel sprocket Rear brake disc Rear wheel sprocket...
  • Page 83 CHAS REAR WHEEL AND BRAKE DISC Order Job / Part Q’ty Remarks Disassembling the rear wheel Disassemble the parts in the order listed. Oil seal Circlip Bearing Collar For assembly, reverse the disassembly procedure. 4-11...

  • Page 84: Removing The Rear Wheel

    CHAS REAR WHEEL AND BRAKE DISC EAS00561 REMOVING THE REAR WHEEL 1. Stand the vehicle on a level surface. WARNING Securely support the vehicle so that there is no danger of it falling over. NOTE: NOTE: Place the vehicle on a suitable stand so that the rear wheel is elevated.

  • Page 85: Checking The Rear Wheel

    CHAS REAR WHEEL AND BRAKE DISC EAS00566 CHECKING THE REAR WHEEL 1. Check: • rear wheel axle • rear wheel • wheel bearings • oil seals Refer “CHECKING FRONT WHEEL”. 2. Check: • tire • rear wheel Damage / wear → Replace. Refer to “CHECKING THE TIRES”...

  • Page 86: Installing The Rear Wheel

    CHAS REAR WHEEL AND BRAKE DISC 2. Replace: • rear wheel sprocket a. Remove the self-locking nuts and the rear wheel sprocket. b. Clean the rear wheel drive hub with a clean cloth, especially the surfaces that contact the sprocket. c.

  • Page 87: Front And Rear Brakes

    CHAS FRONT AND REAR BRAKES EAS00577 FRONT AND REAR BRAKES FRONT BRAKE PADS 6 Nm (0.6 m•kg, 4.3 ft•lb) 23 Nm (2.3 m•kg, 17 ft•lb) Order Job / Part Q’ty Remarks Removing the front brake pads Remove the parts in the order listed. Brake caliper Brake pad Brake pad support...

  • Page 88: Rear Brake Pads

    CHAS FRONT AND REAR BRAKES EAS00578 REAR BRAKE PADS 6 Nm (0.6 m•kg, 4.3 ft•lb) 23 Nm (2.3 m•kg, 17 ft•lb) 18 Nm (1.8 m•kg, 13 ft•lb) 10 Nm (1.0 m•kg, 7.2 ft•lb) 23 Nm (2.3 m•kg, 17 ft•lb) Order Job / Part Q’ty Remarks...

  • Page 89: Replacing The Front Brake Pads

    CHAS FRONT AND REAR BRAKES EAS00579 CAUTION: Disc brake components rarely require dis- assembly. Therefore, always follow these preventive measures: WARNING • Never disassemble brake components unless absolutely necessary. • If any connection on the hydraulic brake system is disconnected, the entire brake system must be disassembled, drained, cleaned, properly filled, and bled after reassembly.
  • Page 90 CHAS FRONT AND REAR BRAKES 3. Measure: • brake pad wear limit Out of specification → Replace the brake pads as a set. Brake pad wear limit 0.8 mm (0.03 in) 4. Install: • brake pads NOTE: NOTE: Always install new brake pads and a new brake pad spring as a set.

  • Page 91: Replacing The Rear Brake Pads

    CHAS FRONT AND REAR BRAKES 8. Check: • brake lever operation Soft or spongy feeling → Bleed the brake system. Refer to “BLEEDING THE HYDRAULIC BRAKE SYSTEM” in chapter 3. EAS00583 REPLACING THE REAR BRAKE PADS NOTE: NOTE: When replacing the brake pads, it is not neces- sary to disconnect the brake hose or disas- semble the brake caliper.
  • Page 92 CHAS FRONT AND REAR BRAKES a. Connect a clear plastic hose tightly to the bleed screw . Put the other end of the hose into an open container. b. Loosen the bleed screw and push the brake caliper pistons into the brake caliper with your finger.

  • Page 93: Front Brake Master Cylinder

    CHAS FRONT AND REAR BRAKES EAS00584 FRONT BRAKE MASTER CYLINDER 6 Nm (0.6 m•kg, 4.3 ft•lb) 6 Nm (0.6 m•kg, 4.3 ft•lb) 9 Nm (0.9 m•kg, 6.5 ft•lb) 26 Nm (2.6 m•kg, 19 ft•lb) Order Job / Part Q’ty Remarks Removing the front brake master Remove the parts in the order listed.
  • Page 94 CHAS FRONT AND REAR BRAKES EAS00585 2 Nm (0.2 m•kg, 1.4 ft•lb) Order Job / Part Q’ty Remarks Disassembling the rear brake Remove the parts in the order listed. master cylinder Brake master cylinder cap Brake master cylinder reservoir dia- phragm Brake master cylinder reservoir float Brake master cylinder boot...

  • Page 95: Rear Brake Master Cylinder

    CHAS FRONT AND REAR BRAKES EAS00586 REAR BRAKE MASTER CYLINDER 10 Nm (1.0 m•kg, 7.2 ft•lb) 1 Nm (0.1 m•kg, 0.7 ft•lb) 26 Nm (2.6 m•kg, 19 ft•lb) 10 Nm (1.0 m•kg, 7.2 ft•lb) Order Job / Part Q’ty Remarks Removing the rear brake master Remove the parts in the order listed.
  • Page 96 CHAS FRONT AND REAR BRAKES EAS00587 Order Job / Part Q’ty Remarks Removing the rear brake master Remove the parts in the order listed. cylinder Brake master cylinder kit Circlip Brake master cylinder joint O-ling For assembly, reverse the disassembly procedure.

  • Page 97: Disassembling The Front Brake Master Cylinder

    CHAS FRONT AND REAR BRAKES EAS00588 DISASSEMBLING THE FRONT BRAKE MASTER CYLINDER NOTE: NOTE: Before disassembling the front brake master cylinder, drain the brake fluid from the entire brake system. 1. Remove: • union bolt • copper washers • brake hose NOTE: NOTE: To collect any remaining brake fluid, place a...

  • Page 98: Checking The Front And Rear Brake Master

    CHAS FRONT AND REAR BRAKES EAS00592 CHECKING THE FRONT AND REAR BRAKE MASTER CYLINDERS The following procedure applies to the both of the brake master cylinders. 1. Check: • brake master cylinder Damage / scratches / wear → Replace. • brake fluid delivery passages (brake master cylinder body) Obstruction →...

  • Page 99: Assembling And Installing The Front Brake Master

    CHAS FRONT AND REAR BRAKES EAS00598 ASSEMBLING AND INSTALLING THE FRONT BRAKE MASTER CYLINDER WARNING • Before installation, all internal brake com- ponents should be cleaned and lubricated with clean or new brake fluid. • Never use solvents on internal brake com- ponents.
  • Page 100 CHAS FRONT AND REAR BRAKES NOTE: NOTE: • While holding the brake hose, tighten the union bolt as shown. • Turn the handlebar to the left and right to make sure the brake hose does not touch other parts (e.g., wire harness, cables, leads). Correct if necessary.

  • Page 101: Cylinder

    CHAS FRONT AND REAR BRAKES 6. Check: • brake lever operation Soft or spongy feeling → Bleed the brake system. Refer to “BLEEDING THE HYDRAULIC BRAKE SYSTEM” in chapter 3. EAS00608 ASSEMBLING THE REAR BRAKE MASTER CYLINDER 1. Install: • O-ling •...
  • Page 102 CHAS FRONT AND REAR BRAKES • When refilling, be careful that water does not enter the brake fluid reservoir. Water will significantly lower the boiling point of the brake fluid and could cause vapor lock. CAUTION: Brake fluid may damage painted surfaces and plastic parts.

  • Page 103: Front Brake Caliper

    CHAS FRONT AND REAR BRAKES EAS00613 FRONT BRAKE CALIPER 26 Nm (2.6 m•kg, 19 ft•lb) 7 Nm (0.7 m•kg, 5.1 ft•lb) 10 Nm (1.0 m•kg, 7.2 ft•lb) 23 Nm (2.3 m•kg, 17 ft•lb) Order Job / Part Q’ty Remarks Removing the front brake caliper Remove the parts in the order listed.
  • Page 104 CHAS FRONT AND REAR BRAKES EAS00614 6 Nm (0.6 m•kg, 4.3 ft•lb) 30 Nm (3.0 m•kg, 22 ft•lb) Order Job / Part Q’ty Remarks Disassembling the front brake Remove the parts in the order listed. caliper Brake pad Brake caliper bracket Brake pad support Sleeve boot Brake caliper piston...

  • Page 105: Rear Brake Caliper

    CHAS FRONT AND REAR BRAKES EAS00616 REAR BRAKE CALIPER 26 Nm (2.6 m•kg, 19 ft•lb) 23 Nm (2.3 m•kg, 17 ft•lb) 18 Nm (1.8 m•kg, 13 ft•lb) 10 Nm (1.0 m•kg, 7.2 ft•lb) 23 Nm (2.3 m•kg, 17 ft•lb) Order Job / Part Q’ty Remarks...

  • Page 106: Disassembling The Rear Brake Caliper

    CHAS FRONT AND REAR BRAKES EAS00617 6 Nm (0.6 m•kg, 4.3 ft•lb) Order Job / Part Q’ty Remarks Disassembling the rear brake caliper Remove the parts in the order listed. Brake pad pin Brake pad Brake pad shim Brake caliper seal Brake caliper piston Brake pad spring Bleed screw...
  • Page 107 CHAS FRONT AND REAR BRAKES EAS00619 DISASSEMBLING THE FRONT BRAKE CALIPER NOTE: NOTE: Before disassembling the brake caliper, drain the brake fluid from the entire brake system. 1. Remove: • union bolt • copper washers • brake hose NOTE: NOTE: Put the end of the brake hose into a container and pump out the brake fluid carefully.

  • Page 108: Checking The Front And Rear Brake Calipers

    CHAS FRONT AND REAR BRAKES 1. Remove: • union bolt • copper washers • brake hose NOTE: NOTE: Put the end of the brake hose into a container and pump out the brake fluid carefully. 2. Remove: • brake caliper piston •...

  • Page 109: Assembling And Installing The Front Brake Caliper

    CHAS FRONT AND REAR BRAKES 1. Check: • brake caliper pistons Rust / scratches / wear → Replace the brake caliper pistons. • brake caliper cylinders Scratches / wear → Replace the brake cali- per assembly. • brake caliper body Cracks / damage →...
  • Page 110 CHAS FRONT AND REAR BRAKES 1. Install: • brake caliper bracket 30 Nm (3.0 m•kg, 22 ft•lb) • brake pads • brake caliper 23 Nm (2.3 m•kg, 17 ft•lb) • copper washers • brake hose • union bolt 26 Nm (2.6 m•kg, 19 ft•lb) WARNING Proper brake hose routing is essential to insure safe vehicle operation.

  • Page 111: Assembling And Installing The Rear Brake Caliper

    CHAS FRONT AND REAR BRAKES 3. Bleed: • brake system Refer to “BLEEDING THE HYDRAULIC BRAKE SYSTEM” in chapter 3. 4. Check: • brake fluid level → Add Below the minimum level mark the recommended brake fluid to the proper level.
  • Page 112 CHAS FRONT AND REAR BRAKES WARNING Proper brake hose routing is essential to insure safe vehicle operation. Refer to “CABLE ROUTING” in chapter 2. CAUTION: When installing the brake hose onto the brake caliper , make sure the brake pipe touches the projection on the brake caliper.
  • Page 113 CHAS FRONT AND REAR BRAKES 5. Check: • brake fluid level → Add Below the minimum level mark the recommended brake fluid to the proper level. Refer to “CHECKING THE BRAKE FLUID LEVEL” in chapter 3. 6. Check: • brake lever operation Soft or spongy feeling →...

  • Page 114: Front Fork

    CHAS FRONT FORK EAS00646 FRONT FORK FRONT FORK LEGS 22 Nm (2.2 m•kg, 16 ft•lb) 20 Nm (2.0 m•kg, 14 ft•lb) 4 Nm (0.4 m•kg, 2.9 ft•lb) 20 Nm (2.0 m•kg, 14 ft•lb) Order Job / Part Q’ty Remarks Removing the front fork legs Remove the parts in the order listed.
  • Page 115 CHAS FRONT FORK EAS00648 28 Nm (2.8 m•kg, 20 ft•lb) 15 Nm (1.5 m•kg, 11 ft•lb) 1 Nm (0.1 m•kg, 0.7 ft•lb) 55 Nm (5.5 m•kg, 40 ft•lb) Order Job / Part Q’ty Remarks Disassembling the front fork legs Remove the parts in the order listed. Guide protector Cap bolt O-ring...
  • Page 116 CHAS FRONT FORK 28 Nm (2.8 m•kg, 20 ft•lb) 15 Nm (1.5 m•kg, 11 ft•lb) 1 Nm (0.1 m•kg, 0.7 ft•lb) 55 Nm (5.5 m•kg, 40 ft•lb) Order Job / Part Q’ty Remarks Oil seal Plug Base valve Gasket O-ring Damper rod O-ring Air bleed screw...

  • Page 117: Removing The Front Fork Legs

    CHAS FRONT FORK EAS00650 REMOVING THE FRONT FORK LEGS The following procedure applies to both of the front fork legs. 1. Stand the vehicle on a level surface. WARNING Securely support the vehicle so that there is no danger of it falling over. NOTE: NOTE: Place the vehicle on a suitable stand so that...

  • Page 118: Disassembling The Front Fork Legs

    CHAS FRONT FORK EAS00652 DISASSEMBLING THE FRONT FORK LEGS The following procedure applies to both of the front fork legs. 1. Remove: • cap bolt (from the damper adjusting rod) a. Install the rod holder between the nut and washer NOTE: NOTE: Use the side of the rod holder that is marked...

  • Page 119: Checking The Front Fork Legs

    CHAS FRONT FORK 6. Remove: • slide metal • oil seal washer • oil seal • piston metal • oil seal clip • dust seal 7. Remove: • base valve • damper rod NOTE: NOTE: While holding the inner tube with the damper rod holder , loosen the base valve.

  • Page 120: Assembling The Front Fork Legs

    CHAS FRONT FORK CAUTION: • The front fork leg has a built-in damper adjusting rod and a very sophisticated internal construction, which are particu- larly sensitive to foreign material. • When disassembling and assembling the front fork leg, do not allow any foreign material to enter the front fork.
  • Page 121 CHAS FRONT FORK 1. Install: • damper rod assembly • inner tube CAUTION: Allow the damper rod assembly to slide slowly down the inner tube until it pro- trudes from the bottom of the inner tube. Be careful not to damage the inner tube. 2.
  • Page 122 CHAS FRONT FORK 6. Install: • dust seal • oil seal clip • oil seal • oil seal washer • slide metal CAUTION: Make sure the numbered side of the oil seal faces up. NOTE: NOTE: • Before installing the oil seal, lubricate its lips with lithium-soap-based grease.
  • Page 123 CHAS FRONT FORK 10.Install: • oil seal (with the fork seal driver Fork seal driver 90890-01442, YM-01442 11.Install: • oil seal clip NOTE: NOTE: Adjust the oil seal clip so that it fits into the outer tube’s groove. 12.Install: • dust seal 13.Fill: •...
  • Page 124 CHAS FRONT FORK 14.Install: • fork spring • washer • cap bolt a. Install the fork spring, and washer. NOTE: NOTE: Install the spring with the smaller pitch fac- ing up b. Install the rod puller and rod puller attach- ment.
  • Page 125 CHAS FRONT FORK g. Fully tighten the cap bolt onto the damper rod by hand. NOTE: NOTE: Make sure that there is a clearance of 0 ~ 1 mm (0 ~ 0.04 in) between the front fork cap bolt and locknut h.

  • Page 126: Installing The Front Fork Legs

    CHAS FRONT FORK EAS00662 INSTALLING THE FRONT FORK LEGS The following procedure applies to both of the front fork legs. 1. Install: • front fork leg Temporarily tighten the upper and lower bracket pinch bolts. NOTE: NOTE: Make sure the inner fork tube is flush with the top of the handlebar holder.

  • Page 127: Handlebar

    CHAS HANDLEBAR EAS00664 HANDLEBAR 4 Nm (0.4 m•kg, 2.9 ft•lb) 1 Nm (0.1 m•kg, 0.7 ft•lb) 9 Nm (0.9 m•kg, 6.5 ft•lb) 27 Nm (2.7 m•kg, 1.9 ft•lb) 4 Nm (0.4 m•kg, 2.9 ft•lb) Order Job / Part Q’ty Remarks Removing the handlebar Remove the parts in the order listed.
  • Page 128 CHAS HANDLEBAR 4 Nm (0.4 m•kg, 2.9 ft•lb) 1 Nm (0.1 m•kg, 0.7 ft•lb) 9 Nm (0.9 m•kg, 6.5 ft•lb) 27 Nm (2.7 m•kg, 1.9 ft•lb) 4 Nm (0.4 m•kg, 2.9 ft•lb) Order Job / Part Q’ty Remarks Left grip Handlebar upper holder Handlebar For installation, reverse the removal...

  • Page 129: Removing The Handlebar

    CHAS HANDLEBAR EAS00666 REMOVING THE HANDLEBAR 1. Stand the vehicle on a level surface. WARNING Securely support the vehicle so that there is no danger of it falling over. 2. Remove: • grip NOTE: NOTE: Blow compressed air between the handlebar and the handlebar grip, and gradually push the grip off the handlebar.
  • Page 130 CHAS HANDLEBAR NOTE: NOTE: • The upper handlebar holders should be installed with the punched mark forward. • First tighten the bolts on the front side of the handlebar upper holder, and then tighten the bolts on the rear side. 3.
  • Page 131 CHAS HANDLEBAR 6. Install: • throttle cable cap 1 Nm (0.1 m•kg, 0.7 ft•lb) • grip cap (lower) 4 Nm (0.4 m•kg, 2.9 ft•lb) • cover (grip cap) 7. Adjust: • throttle cable free play Refer to “ADJUSTING THE THROTTLE CABLE FREE PLAY”...
  • Page 132 CHAS HANDLEBAR 11.Adjust: • clutch lever free play Refer to “ADJUSTING THE CLUTCH CABLE FREE PRAY” in chapter 3. 12.Clamp the clamp portion of the number plate to the handlebar. 13.Insert the end of the fuel tank breather hose into the hole of the steering stem. 4-60...

  • Page 133: Steering Head

    CHAS STEERING HEAD EAS00675 STEERING HEAD UNDER BRACKET 22 Nm (2.2 m•kg, 16 ft•lb) 125 Nm (12.5 m•kg, 90 ft•lb) 38 Nm (3.8 m•kg, 27 ft•lb) Loosen it 1 turn 4 Nm (0.4 m•kg, 2.9 ft•lb) 20 Nm (2.0 m•kg, 14 ft•lb) Order Job / Part Q’ty...

  • Page 134: Removing The Lower Bracket

    CHAS STEERING HEAD EAS00677 REMOVING THE LOWER BRACKET 1. Stand the vehicle on a level surface. WARNING Securely support the vehicle so that there is no danger of it falling over. 2. Remove: • steering stem nut • washer • upper bracket •...

  • Page 135: Installing The Steering Head

    CHAS STEERING HEAD 3. Replace: • lower bearing • bearing races a. Remove the bearing races from the steering head pipe with a long rod hammer. b. Remove the bearing race from the lower bracket with a floor chisel and hammer. c.
  • Page 136 CHAS STEERING HEAD 3. Install: • steering ring nut 4 Nm (0.4 m•kg, 2.9 ft•lb) (with the ring nut wrench Steering nut wrench 90890-01403, YU-33975 a. Tighten the steering ring nut. 38 Nm (3.8 m•kg, 27 ft•lb) b. Loosen it one turn. c.

  • Page 137: Rear Shock Absorber Assembly

    CHAS REAR SHOCK ABSORBER ASSEMBLY EAS00685 REAR SHOCK ABSORBER ASSEMBLY 36 Nm (3.6 m•kg, 26 ft•lb) 16 Nm (1.6 m•kg, 12 ft•lb) 26 Nm (2.6 m•kg, 19 ft•lb) 36 Nm (3.6 m•kg, 26 ft•lb) Order Job / Part Q’ty Remarks Removing the rear shock absorber Remove the parts in the order listed.

  • Page 138: Handling The Rear Shock Absorber And Gas

    CHAS REAR SHOCK ABSORBER ASSEMBLY EAS00687 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 139: Removing The Rear Shock Absorber Assembly

    CHAS REAR SHOCK ABSORBER ASSEMBLY EAS00694 REMOVING THE REAR SHOCK ABSORBER ASSEMBLY 1. Stand the vehicle on a level surface. WARNING Securely support the vehicle so that there is no danger of it falling over. NOTE: NOTE: Place the vehicle on a suitable stand so that the rear wheel is elevated.

  • Page 140: Checking The Rear Shock Absorber Assembly And Gas Cylinder

    CHAS REAR SHOCK ABSORBER ASSEMBLY EAS00696 CHECKING THE REAR SHOCK ABSORBER ASSEMBLY AND GAS CYLINDER 1. Check: • rear shock absorber rod Bends / damage → Replace the rear shock absorber assembly. • rear shock absorber Gas leaks / oil leaks → Replace the rear shock absorber assembly.
  • Page 141 CHAS REAR SHOCK ABSORBER ASSEMBLY 5. Install: • silencer Refer to “EXHAUST PIPE” in chapter 5. • seat and right side cover Refer to “SEAT, SIDE COVERS AND FUEL TANK” in chapter 3. 6. Adjust • spring preload • rebound damping •...

  • Page 142: Swingarm And Drive Chain

    CHAS SWINGARM AND DRIVE CHAIN EAS00700 SWINGARM AND DRIVE CHAIN 16 Nm (1.6 m•kg, 12 ft•lb) 53 Nm (5.3 m•kg, 38 ft•lb) 7 Nm (0.7 m•kg, 5.1 ft•lb) 63 Nm (6.3 m•kg, 46 ft•lb) 36 Nm (3.6 m•kg, 26 ft•lb) Order Job / Part Q’ty...
  • Page 143 CHAS SWINGARM AND DRIVE CHAIN 53 Nm (5.3 m•kg, 38 ft•lb) 54 Nm (5.4 m•kg, 39 ft•lb) 10 Nm (1.0 m•kg, 7.2 ft•lb) Order Job / Part Q’ty Remarks Disassembling the swingarm Disassemble the parts in the order listed. Relay arm Connecting rod Cover Dust seal...

  • Page 144: Removing The Swingarm

    CHAS SWINGARM AND DRIVE CHAIN EAS00703 REMOVING THE SWINGARM 1. Stand the vehicle on a level surface. WARNING Securely support the vehicle so that there is no danger of it falling over. NOTE: NOTE: Place the vehicle on a suitable stand so that the rear wheel is elevated.

  • Page 145: Removing The Drive Chain

    CHAS SWINGARM AND DRIVE CHAIN EAS00706 REMOVING THE DRIVE CHAIN 1. Stand the vehicle on a level surface. WARNING Securely support the vehicle so that there is no danger of it falling over. NOTE: NOTE: Place the vehicle on a suitable stand so that the rear wheel is elevated.

  • Page 146: Checking The Drive Chain

    CHAS SWINGARM AND DRIVE CHAIN 4. Check: • collars • oil seals Damage / wear → Replace. • bearings Damage / pitting → Replace. • bushings Damage / wear → Replace. 5. Check: • connecting rod • relay arm Damage / wear → Replace. 6.
  • Page 147 CHAS SWINGARM AND DRIVE CHAIN NOTE: NOTE: • While measuring the 15-link section, push down on the drive chain to increase its ten- sion. • Perform this measurement at two or three dif- ferent places. 2. Check: • drive chain Stiffness →...

  • Page 148: Checking The Drive Chain Support

    CHAS SWINGARM AND DRIVE CHAIN 6. Check: • drive sprocket • rear wheel sprocket wear → Replace More than 1 / 4 tooth the drive chain sprockets as a set. Bent teeth → Replace the drive chain sprockets as a set. Correct Drive chain roller Drive chain sprocket...
  • Page 149 CHAS SWINGARM AND DRIVE CHAIN 2. Install: • bearing • oil seal (with the relay arm) NOTE: NOTE: • Apply the molybdenum disulfide grease on the bearing when installing. • Install the bearing by pressing it on the side having the manufacture’s marks or numbers. Installed depth of bearings Depth : 4.5 mm (0.18 in)

  • Page 150: Installing The Drive Chain

    CHAS SWINGARM AND DRIVE CHAIN 5. Install: • relay arm 54 Nm (5.4 m•kg, 39 ft•lb) 6. Install: • swingarm • pivot shaft • pivot shaft nut 63 Nm (6.3 m•kg, 46 ft•lb) 7. Install: • rear shock absorber • rear wheel Refer to “REAR WHEEL AND BRAKE DISC”.
  • Page 151 CHAS SWINGARM AND DRIVE CHAIN 3. Install: • master link clip CAUTION: • The closed end of the master link clip must face in the direction of drive chain rotation. • Never install a new drive chain onto worn drive chain sprockets; this will dramati- cally shorten the drive chain’s life.
  • Page 152 CHAPTER 5 ENGINE ENGINE..........5-1 DRIVE SPROCKET .
  • Page 153 KICK STARTER AND SHIFT SHAFT ......5-26 PRIMARY DRIVE GEAR ........5-26 KICK STARTER AND SHIFT SHAFT .

  • Page 154: Engine

    ENGINE ENGINE ENGINE DRIVE SPROCKET 60 Nm (6.0 m•kg, 43 ft•lb) 5 Nm (0.5 m•kg, 3.6 ft•lb) Order Job / Part Q’ty Remarks Removing the drive sprocket Remove the parts in the order listed. Drive chain Loosen. Refer to “ADJUSTING THE DRIVE CHAIN SLACK”...

  • Page 155: Exhaust Pipe

    ENGINE EXHAUST PIPE 12 Nm (1.2 m•kg, 8.7 ft•lb) 12 Nm (1.2 m•kg, 8.7 ft•lb) 12 Nm (1.2 m•kg, 8.7 ft•lb) 12 Nm (1.2 m•kg, 8.7 ft•lb) Order Job / Part Q’ty Remarks Removing the exhaust pipe Remove the parts in the order listed. Refer to “SEAT, SIDE COVERS AND Seat FUEL TANK”...

  • Page 156: Silencer Fiber Replacement

    2. Remove: • inner pipe 3. Replace: • fiber 4. Install: • inner pipe NOTE: NOTE: Fully apply Yamaha bond No. 1215 (Three ® bond No. 1215 ) or equivalent as shown. Yamaha bond No.1215 ® (Three Bond No.1215 90890-85505 5.
  • Page 157 ENGINE EAS00191 ENGINE 63 Nm (6.3 m•kg, 46 ft•lb) 63 Nm (6.3 m•kg, 46 ft•lb) Order Job / Part Q’ty Remarks Removing the engine Remove the parts in the order listed. NOTE: NOTE: Place a suitable stand under the frame and engine.
  • Page 158 ENGINE 63 Nm (6.3 m•kg, 46 ft•lb) 63 Nm (6.3 m•kg, 46 ft•lb) Order Job / Part Q’ty Remarks CDI magneto lead Disconnect. Drive chain Loosen. Refer to “ADJUSTING THE DRIVE CHAIN SLACK” in chapter 3. Engine mount nut Engine mount bolt Pivot shaft nut Pivot shaft Engine...

  • Page 159: Installing The Engine

    ENGINE EAS00192 INSTALLING THE ENGINE 1. Install: • engine • pivot shaft • engine mount bolt (front) • engine mount bolt (lower) NOTE: NOTE: Do not fully tighten the bolts. 2. Tighten: • pivot shaft nut 63 Nm (6.3 m•kg, 46 ft•lb) •...

  • Page 160: Cylinder Head, Cylinder And Piston

    CYLINDER HEAD, CYLINDER AND PISTON EAS00221 CYLINDER HEAD, CYLINDER AND PISTON CYLINDER HEAD 20 Nm (2.0 m•kg, 14 ft•lb) 30 Nm (3.0 m•kg, 22 ft•lb) Order Job / Part Q’ty Remarks Removing the cylinder head Remove the parts in the order listed. Coolant Drain Refer to “CHANGING THE COOLANT”...

  • Page 161: Removing The Cylinder Head

    CYLINDER HEAD, CYLINDER AND PISTON EAS00222 REMOVING THE CYLINDER HEAD 1. Remove: • cylinder head nuts NOTE: NOTE: • Loosen the nuts in the proper sequence as shown. • Loosen each nut 1 / 2 of a turn at a time. After all of the nuts are fully loosened, remove them.

  • Page 162: Installing The Cylinder Head

    CYLINDER HEAD, CYLINDER AND PISTON d. Place a 400 ~ 600 grit wet sandpaper on the surface plate and resurface the cylinder head using a figure-eight sanding pattern. NOTE: NOTE: To ensure an even surface, rotate the cylinder head several times. EAS00233 INSTALLING THE CYLINDER HEAD 1.

  • Page 163: Cylinder And Piston

    CYLINDER HEAD, CYLINDER AND PISTON EAS00251 CYLINDER AND PISTON 28 Nm (2.8 m•kg, 20 ft•lb) 13 Nm (1.3 m•kg, 9.4 ft•lb) 13 Nm (1.3 m•kg, 9.4 ft•lb) Order Job / Part Q’ty Remarks Removing the cylinder and piston Remove the parts in the order listed. Cylinder head Refer to “CYLINDER HEAD”.

  • Page 164: Removing The Cylinder And Piston

    CYLINDER HEAD, CYLINDER AND PISTON EAS00253 REMOVING THE CYLINDER AND PISTON 1. Remove: • piston pin clip NOTE: NOTE: Before removing the piston pin clip, cover the crankcase opening with a clean rag to prevent the piston pin clip from falling into the crank- case.
  • Page 165 CYLINDER HEAD, CYLINDER AND PISTON 2. Measure: • piston-to-cylinder clearance a. Measure cylinder bore “C” with the cylinder bore gauge. NOTE: NOTE: Measure cylinder bore “C” by taking side-to- side and front-to-back measurements of the cylinder. Then, find the average of the mea- surements.

  • Page 166: Combination Of Piston And Cylinder

    CYLINDER HEAD, CYLINDER AND PISTON COMBINATION OF PISTON AND CYLINDER 1. Check: • cylinder mark Cylinder mark Cylinder size 47.500 ~ 47.502 mm (1.8701 ~ 1.8702 in) 47.504 ~ 47.506 mm (1.8702 ~ 1.8703 in) 47.508 ~ 47.510 mm (1.8704 ~ 1.8705 in) 47.512 ~ 47.514 mm (1.87055 ~ 1.87063 in) 2.

  • Page 167: Checking The Piston Ring

    CYLINDER HEAD, CYLINDER AND PISTON EAS00263 CHECKING THE PISTON RING 1. Measure: • piston ring side clearance Out of specification → Replace the piston and piston ring as a set. NOTE: NOTE: Before measuring the piston ring side clear- ance, eliminate any carbon deposits from the piston ring grooves and piston ring.

  • Page 168: Checking The Small End Bearing

    CYLINDER HEAD, CYLINDER AND PISTON Piston pin outside diameter 13.996 ~ 14.000 mm (0.5510 ~ 0.5512 in) <Limit>: 13.975 mm (0.5502 in) 3. Measure: • piston pin bore inside diameter Out of specification → Replace the piston. Piston pin bore inside diameter 14.004 ~ 14.015 mm (0.5513 ~ 0.5518 in) <Limit>: 14.040 mm (0.5528 in)

  • Page 169: Installing The Piston And Cylinder

    CYLINDER HEAD, CYLINDER AND PISTON EAS00267 INSTALLING THE PISTON AND CYLINDER 1. Install: • piston ring NOTE: NOTE: • Take care not to scratch the piston or damage the piston ring. • Align the piston ring gap with the pin •...
  • Page 170 CYLINDER HEAD, CYLINDER AND PISTON 4. Lubricate: • piston • piston ring • cylinder (with the recommended lubricant) Recommended lubricant Engine oil 5. Install: • cylinder • cylinder nut 28 Nm (2.8 m•kg, 20 ft•lb) NOTE: NOTE: • While compressing the piston ring with one hand, install the cylinder with the other hand.

  • Page 171: Clutch

    CLUTCH EAS00274 CLUTCH CLUTCH 70 Nm (7.0 m•kg, 51 ft•lb) 6 Nm (0.6 m•kg, 4.3 ft•lb) 10 Nm (1.0 m•kg, 7.2 ft•lb) Order Job / Part Q’ty Remarks Removing the clutch Transmission oil Drain Refer to “CHANGING THE TRANSMISSION OIL” in chapter 3. Clutch cable Disconnect Clutch cover...
  • Page 172 CLUTCH 70 Nm (7.0 m•kg, 51 ft•lb) 6 Nm (0.6 m•kg, 4.3 ft•lb) 10 Nm (1.0 m•kg, 7.2 ft•lb) Order Job / Part Q’ty Remarks Conical washer Clutch boss Washer Primary drive gear Spacer Washer Push lever shaft Spring Oil seal Bearing For installation, reverse the removal procedure.

  • Page 173: Removing The Clutch

    CLUTCH EAS00276 REMOVING THE CLUTCH 1. Remove: • clutch cover • gasket NOTE: NOTE: Loosen each bolt 1 / 4 of a turn at a time, in stages and in a crisscross pattern. After all of the bolts are fully loosened, remove them.

  • Page 174: Checking The Friction Plates

    CLUTCH EAS00280 CHECKING THE FRICTION PLATES 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.

  • Page 175: Checking The Clutch Springs

    CLUTCH EAS00282 CHECKING THE CLUTCH SPRINGS 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 Out of specification → Replace the clutch springs as a set.

  • Page 176: Checking The Push Lever Shaft

    CLUTCH CHECKING THE PUSH LEVER SHAFT 1. Check: • push lever shaft Wear / damage → Replace. EAS00288 CHECKING THE CLUTCH PUSH RODS 1. Check: • push rod 1 • ball • push rod 2 Wear / damage / bend → Replace. EAS00298 INSTALLING THE CLUTCH 1.
  • Page 177 CLUTCH 4. Install: • clutch boss nut 70 Nm (7.0 m•kg, 51 ft•lb) NOTE: NOTE: While holding the clutch boss with the univer- sal clutch holder , tighten the clutch boss nut. Universal clutch holder 90890-04086, YM-91042 5. Lubricate: • friction plates •...
  • Page 178 CLUTCH 8. Install: • pressure plate 1 NOTE: NOTE: Align the punch mark on the pressure plate with the punch mark on the clutch boss. 9. Install: • clutch spring • clutch spring bolt 6 Nm (0.6 m•kg, 4.3 ft•lb) NOTE: NOTE: Tighten the clutch spring bolts in stages and in...

  • Page 179: Kick Starter And Shift Shaft

    KICK STARTER AND SHIFT SHAFT EAS00327 KICK STARTER AND SHIFT SHAFT PRIMARY DRIVE GEAR 10 Nm (1.0 m•kg, 7.2 ft•lb) 10 Nm (1.0 m•kg, 7.2 ft•lb) 10 Nm (1.0 m•kg, 7.2 ft•lb) 79 Nm (7.9 m•kg, 57 ft•lb) Order Job / Part Q’ty Remarks Removing the primary drive gear...
  • Page 180 KICK STARTER AND SHIFT SHAFT 10 Nm (1.0 m•kg, 7.2 ft•lb) 10 Nm (1.0 m•kg, 7.2 ft•lb) 10 Nm (1.0 m•kg, 7.2 ft•lb) 79 Nm (7.9 m•kg, 57 ft•lb) Order Job / Part Q’ty Remarks Primary drive gear For installation, reverse the removal procedure.
  • Page 181 KICK STARTER AND SHIFT SHAFT KICK STARTER AND SHIFT SHAFT 10 Nm (1.0 m•kg, 7.2 ft•lb) Order Job / Part Q’ty Remarks Removing the kick starter shaft and Remove the parts in the order listed. shift shaft Circlip Washer Kick idle gear Spring guide Torsion spring Washer...
  • Page 182 KICK STARTER AND SHIFT SHAFT 10 Nm (1.0 m•kg, 7.2 ft•lb) Order Job / Part Q’ty Remarks Washer Stopper lever Collar Shift shaft spring Oil seal Oil seal For installation, reverse the removal procedure. 5-29...

  • Page 183: Removing The Primary Drive Gear

    KICK STARTER AND SHIFT SHAFT REMOVING THE PRIMARY DRIVE GEAR 1. Remove: • nut (primary drive gear) NOTE: NOTE: Hold the drive gear holder onto the crank- case using the M6 bolts Drive gear holder 90890-01495, YM-01495 REMOVING THE KICK SHAFT ASSEMBLY 1.

  • Page 184: Checking The Shift Shaft

    KICK STARTER AND SHIFT SHAFT EAS00328 CHECKING THE SHIFT SHAFT 1. Check: • shift shaft Bends / damage / wear → Replace. • spring Damage / wear → Replace. EAS00330 CHECKING THE STOPPER LEVER 1. Check: • stopper lever Bends / damage → Replace. •...
  • Page 185 KICK STARTER AND SHIFT SHAFT 2. Install: • stopper lever assembly (with the shift shaft NOTE: NOTE: Apply the transmission oil on the stopper lever assembly. 3. Install: • stopper lever • shift shaft NOTE: NOTE: • Apply transmission oil on the shift shaft. •...

  • Page 186: Installing The Kick Starter Shaft Assembly

    KICK STARTER AND SHIFT SHAFT INSTALLING THE KICK STARTER SHAFT ASSEMBLY 1. Install: • kick starter gear • washer • torsion spring NOTE: NOTE: Make sure the stopper of the torsion spring fits into the hole in the other side of the stopper of the kick starter shaft 2.

  • Page 187: Installing The Primary Drive Gear

    KICK STARTER AND SHIFT SHAFT INSTALLING THE PRIMARY DRIVE GEAR 1. Install: • straight key 2. Install: • primary drive gear • washer • primary drive gear nut NOTE: NOTE: Install the conical washer to the crankshaft as shown in the illustration. 3.
  • Page 188 KICK STARTER AND SHIFT SHAFT 7. Install: • bolt (right crankcase cover) 10 Nm (1.0 m•kg, 7.2 ft•lb) • copper washer (oil drain bolt) • oil drain bolt 10 Nm (1.0 m•kg, 7.2 ft•lb) • copper washer (coolant drain bolt) •...

  • Page 189: Cdi Magneto

    CDI MAGNETO EAS00343 CDI MAGNETO 8 Nm (0.8 m•kg, 5.8 ft•lb) 33 Nm (3.3 m•kg, 24 ft•lb) 5 Nm (0.5 m•kg, 3.6 ft•lb) Order Job / Part Q’ty Remarks Removing the CDI magneto Remove the parts in the order listed. Seat Fuel tank CDI magneto lead...

  • Page 190: Removing The Rotor

    CDI MAGNETO EAS00346 REMOVING THE ROTOR 1. Remove: • nut • washer NOTE: NOTE: While holding the rotor with the rotor holding tool , loosen the rotor nut. Rotor holding tool 90890-01235, YU-1325 2. Remove: • rotor (with the flywheel puller •...

  • Page 191: Installing The Cdi Magneto

    CDI MAGNETO INSTALLING THE CDI MAGNETO 1. Install: • stator • screw NOTE: NOTE: Temporarily tighten the screw at this point. 2. Install: • woodruff key • rotor NOTE: NOTE: • Clean the tapered portions of the crankshaft and rotor. •...
  • Page 192 CDI MAGNETO 5. Tighten: • screw (stator) 8 Nm (0.8 m•kg, 5.8 ft•lb) 6. Check: • ignition timing Re-check the ignition timing. 7. Connect: • CDI magneto lead Refer to “CABLE ROUTING” in chapter 2. 8. Install: • gasket (left crankcase cover) •...

  • Page 193: Crankcase And Crankshaft

    CRANKCASE AND CRANKSHAFT EAS00381 CRANKCASE AND CRANKSHAFT CRANKCASE AND CRANKSHAFT 8 Nm (0.8 m•kg, 5.8 ft•lb) 20 Nm (2.0 m•kg, 14 ft•lb) 8 Nm (0.8 m•kg, 5.8 ft•lb) Order Job / Part Q’ty Remarks Removing the crankcase and Remove the parts in the order listed. crankshaft Engine Refer to “ENGINE”.

  • Page 194: Dissassembling The Crankcase

    CRANKCASE AND CRANKSHAFT EAS00385 DISSASSEMBLING THE CRANKCASE 1. Remove: • right crankcase (with the crankcase separating tool Crankcase separating tool 90890-01135, YU-1135-A NOTE: NOTE: • Fully tighten the tool holding bolts, but make sure the tool body is parallel with the case. If necessary, one screw may be backed out slightly to level tool body.

  • Page 195: Removing The Crankshaft Bearing

    CRANKCASE AND CRANKSHAFT REMOVING THE CRANKSHAFT BEARING 1. Remove: • bearing NOTE: NOTE: • Remove the bearing from the crankcase by pressing its inner race as shown in • If the bearing is removed together with the crankshaft, remove the bearing using a gen- eral bearing puller as shown in CAUTION:...

  • Page 196: Checking The Crankcase

    CRANKCASE AND CRANKSHAFT 3. Measure: • big end side clearance Out of specification → Replace the big end bearing, crankshaft pin, or connecting rod. Big end side clearance 0.20 ~ 0.70 mm (0.008 ~ 0.028 in) 4. Measure: • crankshaft width Out of specification →...

  • Page 197: Installing The Crankshaft

    EAS00416 ASSEMBLING THE CRANKCASE 1. Apply: • sealant (onto the crankcase mating surfaces) Yamaha bond No. 1215 ® (Three Bond No. 1215 90890-85505 NOTE: NOTE: Do not allow any sealant to come into contact with the oil gallery.
  • Page 198 CRANKCASE AND CRANKSHAFT 2. Install: • dowel pin • right crankcase (onto the left crankcase NOTE: NOTE: • Turn the shift cam to the position shown in the figure so that it does not contact the crankcase when installing the crankcase. •...

  • Page 199: Transmission

    TRANSMISSION EAS00419 TRANSMISSION Order Job / Part Q’ty Remarks Removing the transmission Remove the parts in the order listed. Engine Refer to “ENGINE”. Crankcase Separate. Refer to “CRANKCASE AND CRANKSHAFT”. Shift fork guide bar Shift drum Shift fork-R Shift fork-L Shift fork-C Bearing Circlip...
  • Page 200 TRANSMISSION Order Job / Part Q’ty Remarks 3RD pinion gear Circlip Washer 5TH pinion gear Main axle Bearing Circlip Washer 1ST wheel gear 5TH wheel gear Circlip Washer 4TH wheel gear 3RD wheel gear 6TH wheel gear Drive axle 5-47...
  • Page 201 TRANSMISSION Order Job / Part Q’ty Remarks 2ND wheel gear Washer Bearing Oil seal Bearing For installation, reverse the removal procedure. 5-48...

  • Page 202: Removing The Transmission

    TRANSMISSION EAS00420 REMOVING THE TRANSMISSION 1. Remove: • right crankcase Refer to “CRANKCASE AND CRANK- SHAFT”. 2. Remove: • main axle • drive axle NOTE: NOTE: • Remove assembly carefully. Note the position of each part. Pay particular attention to the location and direction of shift forks.

  • Page 203: Checking The Shift Drum Assembly

    TRANSMISSION EAS00422 CHECKING THE SHIFT DRUM ASSEMBLY 1. Check: • shift drum grooves Damage / scratches / wear → Replace the shift drum assembly. • shift drum segment Damage / wear → Replace the shift drum assembly. • shift drum bearing Damage / pitting →...

  • Page 204: Installing The Transmission

    TRANSMISSION 4. Check: • transmission gear engagement (each pinion gear to its respective wheel gear) Incorrect → Reassemble the transmission axle assemblies. 5. Check: • transmission gear movement Rough movement → Replace the defective part(s). 6. Check: • circlips Bends / damage / looseness → Replace. INSTALLING THE TRANSMISSION 1.
  • Page 205 TRANSMISSION 3. Install: • washer • circlip NOTE: NOTE: • Be sure the circlip sharp-edged corner positioned opposite side to the washer and gear • Be sure the circlip end is positioned at axle spline groove 4. Install: • collar NOTE: NOTE: •...
  • Page 206 TRANSMISSION NOTE: NOTE: • Mesh the shift fork-L with the 6th wheel gear and shift fork-R with the 5TH wheel gear on the drive axle. • Mesh the shift fork-C with the 3RD / 4TH pinion gear on the main axle. 7.
  • Page 207 COOL CHAPTER 6 COOLING SYSTEM RADIATOR ..........6-1 CHECKING THE RADIATOR .

  • Page 208: Cooling System

    COOL RADIATOR EAS00454 COOLING SYSTEM RADIATOR 1 Nm (0.1 m•kg, 0.7 ft•lb) 1 Nm (0.1 m•kg, 0.7 ft•lb) 1 Nm (0.1 m•kg, 0.7 ft•lb) Order Job / Part Q’ty Remarks Removing the radiator Remove the parts in the order listed. Air scoop Refer to “SEAT, SIDECOVERS AND FUEL TANK”...

  • Page 209: Checking The Radiator

    COOL RADIATOR EAS00455 CHECKING THE RADIATOR 1. Check: • radiator fins Obstruction → Clean. Apply compressed air to the rear of the radiator. Damage → Repair or replace. NOTE: NOTE: Straighten any flattened fins with a thin, flat- head screwdriver. 2.
  • Page 210 COOL RADIATOR 2. Check: • cooling system Leaks → Repair or replace any faulty part. a. Attach the radiator cap tester to the radi- ator. Radiator cap tester 90890-01325, YU-24460-01 Radiator cap tester adapter 90890-01352, YU-33984 b. Apply 100 kPa (1.0 kg / cm , 14.22 psi) of pressure.

  • Page 211: Water Pump

    COOL WATER PUMP EAS00468 WATER PUMP 10 Nm (1.0 m•kg, 7.2 ft•lb) 14 Nm (1.4 m•kg, 10 ft•lb) 10 Nm (1.0 m•kg, 7.2 ft•lb) Order Job / Part Q’ty Remarks Removing the water pump Remove the parts in the order listed. NOTE: NOTE: It is not necessary to remove the water...

  • Page 212: Checking The Water Pump

    COOL WATER PUMP EAS00472 CHECKING THE WATER PUMP 1. Check: • oil seal Damage / wear → Replace. 2. Check: • bearing Rough movement → Replace. 3. Check: • impeller Cracks / damage / wear → Replace. 4. Check: • water pump impeller shaft Damage / wear →...
  • Page 213 COOL WATER PUMP 2. Install: • bearing NOTE: NOTE: Install the bearing by pressing its outer race parallel. 3. Install: • water pump impeller shaft • washer • impeller 14 Nm (1.4 m•kg, 10 ft•lb) NOTE: NOTE: • Take care so that the oil seal lip is not dam- aged or the spring does not slip off its posi- tion.
  • Page 214 CARB CHAPTER 7 CARBURETOR CARBURETOR AND REED VALVE ......7-1 CHECKING THE CARBURETOR ......7-4 CHECKING THE REED VALVE .

  • Page 215: Carburetor And Reed Valve

    CARB CARBURETOR AND REED VALVE EAS00480 CARBURETOR CARBURETOR AND REED VALVE 8 Nm (0.8 m•kg, 5.8 ft•lb) 1 Nm (0.1 m•kg, 0.7 ft•lb) Order Job / Part Q’ty Remarks Removing the carburetor and reed Remove the parts in the order listed. valve Clamp Loosen.
  • Page 216 CARB CARBURETOR AND REED VALVE Order Job / Part Q’ty Remarks Disassembling the carburetor Remove the parts in the order listed Mixing chamber top Throttle valve Jet needle Ring Throttle valve spring Gascket (mixing chamber top) Float chamber Gascket (float chamber) Float pin Float Needle valve...
  • Page 217 CARB CARBURETOR AND REED VALVE Order Job / Part Q’ty Remarks Starter plunger Throttle stop screw Pilot air screw For assembly, reverse the disassembly procedure.

  • Page 218: Checking The Carburetor

    CARB CARBURETOR AND REED VALVE EAS00485 CHECKING THE CARBURETOR 1. Check: • carburetor body • float chamber • jet housing Cracks / damage → Replace. 2. Check: • fuel passages Obstruction → Clean. a. Wash the carburetor in a petroleum-based solvent.

  • Page 219: Checking The Reed Valve

    CARB CARBURETOR AND REED VALVE 7. Check: • jet needle • main nozzle • main jet • main nozzle holder • pilot jet • starter plunger Bends / damage / wear → Replace. Obstruction → Clean. Blow out the jets with compressed air. 8.

  • Page 220: Assembly The Reed Valve

    CARB CARBURETOR AND REED VALVE ASSEMBLY THE REED VALVE 1. Install: • reed valve • reed valve stopper • screw (reed valve) 1 Nm (0.1 m•kg, 0.7 ft•lb) ® LOCTITE NOTE: NOTE: • Install the reed valve with the reed valve bending as shown.
  • Page 221 CARB CARBURETOR AND REED VALVE 2. Install: • starter plunger 3. Install: • pilot jet • main nozzle • main jet holder • main jet NOTE: NOTE: Install the main nozzle with its chamfered side facing the carburetor. 4. Install: •...

  • Page 222: Installing The Reed Valve

    CARB CARBURETOR AND REED VALVE 8. Install: • throttle cable • mixing chamber top • gascket (mixing chamber top) • spring (throttle valve) • ring • throttle valve NOTE: NOTE: • While compressing the spring, connect the throttle cable. • Align the cut in the ring with the throttle cable.

  • Page 223: Measuring And Adjusting The Fuel Level

    CARB CARBURETOR AND REED VALVE 2. Adjust: • throttle cable free play Throttle cable free play 3 ~ 5 mm (0.12 ~ 0.20 in) Refer to “ADJUSTING THE THROTTLE CABLE FREE PLAY” in chapter 3. EAS00498 MEASURING AND ADJUSTING THE FUEL LEVEL 1.
  • Page 224 ELEC CHAPTER 8 ELECTRICAL SYSTEM ELECTRICAL COMPONENTS ....... . 8-1 CHECKING SWITCH CONTINUITY .

  • Page 225: Electrical System

    ELEC ELECTRICAL COMPONENTS EAS00729 ELECTRICAL SYSTEM ELECTRICAL COMPONENTS Ignition coil Engine stop switch CDI unit CDI magneto...

  • Page 226: Checking Switch Continuity

    ELEC CHECKING SWITCH CONTINUITY CEAS00730 CHECKING SWITCH CONTINUITY “∞” “0” Check each switch for continuity with the pocket tester. If the continuity reading is incor- rect, check the wiring connections and if nec- essary, replace the switch. “Ω × 1” CAUTION: Never insert the tester probes into the cou- pler terminal slots.

  • Page 227: Ignition System

    ELEC IGNITION SYSTEM EAS00736 EAS00740 IGNITION SYSTEM 1. Spark plug TROUBLESHOOTING • Check the condition of the spark plug. • Check the spark plug type. The ignition system fails to operate (no • Measure the spark plug gap. spark or intermittent spark). Refer to “CHECKING THE SPARK PLUG”...
  • Page 228 ELEC IGNITION SYSTEM EAS00744 EAS00746 3. Spark plug cap resistance 4. Ignition coil resistance • Remove the spark plug cap from the spark • Disconnect the ignition coil connectors from plug lead. the ignition coil terminals. • Connect the pocket tester (“Ω × 1k” range) •...
  • Page 229 ELEC IGNITION SYSTEM EAS00750 EAS00748 5. Engine stop switch 6. Pickup coil resistance • Check the engine stop switch for continuity. • Disconnect the pickup coil coupler from the • Connect the pocket tester (Ω × 1) to the wire harness. •...
  • Page 230 ELEC IGNITION SYSTEM EAS00775 EAS00754 7. Charging coil resistance 8. Wiring • Disconnect the charging coil coupler from • Check the entire ignition system’s wiring. the wire harness. Refer to “WIRING DIAGRAM”. • Connect the pocket tester (Ω × 100) to the •...
  • Page 231 CHAPTER 9 TUNING ENGINE..........9-1 CARBURETOR SETTING .

  • Page 232: Engine

    ENGINE TUNING ENGINE CARBURETOR SETTING • The role of fuel is to cool the engine, and in the case of a 2-stroke engine, to lubricate the engine in addition to power generation. Accordingly, if a mixture of air and fuel is too lean, abnormal combustion will occur, and engine seizure may result.

  • Page 233: Test Run

    ENGINE TEST RUN After warming up the engine equipped with the standard type carburetor(s) and spark plug(s), run two or three laps of the circuit and check the smooth operation of the engine and discol- oration of spark plug(s). Discoloration Condition of spark plug Insulator is dry and burnt Normal brown.

  • Page 234: Main Jet Adjustment

    ENGINE MAIN JET ADJUSTMENT The richness of air-fuel mixture with 3 / 4 ~ 4 / 4 throttle can be set by changing the main jet Standard main jet #138 1. Spark plug is too hot. Select a main jet having higher calibrating No.

  • Page 235: Jet Needle Groove Position Adjustment

    ENGINE JET NEEDLE GROOVE POSITION ADJUSTMENT Should the engine be hard to run smoothly at intermediate speeds, the jet needle must be adjusted. If the mixture is too rich or too lean at intermediate speed operation, irregular engine operation and poor acceleration will result. Whether or not the richness of the mixture is proper is hard to be determined by means of the spark plug and therefore, it should be...

  • Page 236: Road Condition And Examples Of Carburetor

    ENGINE Rich Lean Diameter of straight portion φ 2.405 mm (0.0947 in) φ 2.415 mm (0.0951 in) φ 2.425 mm (0.0955 in) Clip position Rich 1 richer NBKE-3rd groove NBKF-3rd groove NBKG-3rd groove 0.5 richer NBLE-2nd groove NBLF-2nd groove NBLG-2nd groove NBKE-2nd groove NBKF-2nd groove (STD) NBKG-2nd groove...

  • Page 237: Change Of The Heat Range Of Spark Plugs

    ENGINE Symptom Setting Checking Closed to 1 / 4 throttle Use jet needle with a larger diameter. Poor acceleration Turn in pilot air screw. White smoke Unstable at low speeds Lower jet needle clip position. Pinking noise (1 groove down) Turn in pilot air screw.

  • Page 238: Chassis

    ENGINE / CHASSIS NOTE: NOTE: • When checking the discoloration of spark plugs, be sure to stop the engine immediately after a run and check. • Avoid racing. • When changing the heat range of spark plugs, never attempt to change it more than ±1 rank.

  • Page 239: Sprocket

    CHASSIS • In actuality, it is very difficult to achieve set- tings suitable for the entire course and some settings may be sacrificed. Thus, the settings should be matched to the portion of the course that has the greatest effect on the race result.

  • Page 240: Tire Pressure

    CHASSIS TIRE PRESSURE Tire pressure should be adjust to suit the road surface condition of the circuit. Standard tire pressure 100 kPa (1.0 kgf / cm , 15 psi) • Under a rainy, muddy, sandy, or slippery condition, the tire pressure should be lower for a larger area of contact with the road surface.

  • Page 241: Change In Level And Characteristics Of Fork Oil

    CHASSIS CHANGE IN LEVEL AND CHARACTERISTICS OF FORK OIL Damping characteristic near the final stroke can be changed by changing the fork oil amount. CAUTION: Adjust the oil level in 5 mm (0.2 in) incre- ments or decrements. Too low oil level causes the front fork to produce a noise at full rebound or the rider to feel some pres- sure on his hands or body.

  • Page 242: Front Fork Setting Parts

    CHASSIS 2. Use of stiff spring Generally a stiff spring gives a stiff riding feeling. Rebound damping tends to become weaker, resulting in lack of a sense of con- tact with the road surface or in a vibrating handlebar. To set a stiff spring: •...

  • Page 243: Rear Suspension Setting

    CHASSIS REAR SUSPENSION SETTING The rear suspension setting should be made depending on the rider’s feeling of an actual run and the circuit conditions. The rear suspension setting includes the fol- lowing two factors: 1. Setting of spring preload • Change the set length of the spring. •...

  • Page 244: Setting Of Spring After Replacement

    CHASSIS SETTING OF SPRING AFTER REPLACEMENT After replacement, be sure to adjust the spring to the set length [sunken length 75 ~ 85 mm (3.0 ~ 3.3 in)] and set it. 1. Use of soft spring • Set the soft spring for less rebound damp- ing to compensate for its less spring load.

  • Page 245: Rear Shock Absorber Setting Parts

    CHASSIS REAR SHOCK ABSORBER SETTING PARTS • Rear shock spring YZ85: For EUR SPRING SPRING I.D. TYPE RATE PART NUMBER COLOR SOFT 4ES-22212-M0 Brown 4ES-22212-K0 Green STIFF 4ES-22212-G0 For CAN, AUS, NZL SPRING SPRING I.D. TYPE RATE PART NUMBER COLOR SOFT 4ES-22212-G0 4ES-22212-F0...

  • Page 246: Suspension Setting

    CHASSIS SUSPENSION SETTING • Front fork NOTE: • If any of the following symptoms is experienced with the standard position as the base, make reset- ting by reference to the adjustment procedure given in the same chart. • Before any change, set the rear shock absorber sunken length to the standard figure 75 ~ 85 mm (3.0 ~ 3.3 in).
  • Page 247 CHASSIS • Rear shock absorber NOTE: • If any of the following symptoms is experienced with the standard position as the base, make reset- ting by reference to the adjustment procedure given in the same chart. • Adjust the damping in 2-click increments or decrements. Section Symptom Check...
  • Page 248 TRBL SHTG CHAPTER 10 TROUBLESHOOTING STARTING FAILURES ........10-1 ENGINE .

  • Page 249: Troubleshooting

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

  • Page 250: Incorrect Engine Idling Speed

    TRBL INCORRECT ENGINE IDLING SPEED / POOR MEDIUM-AND- HIGH-SPEED PERFORMANCE / FAULTY GEAR SHIFTING SHTG EAS00846 INCORRECT ENGINE IDLING SPEED ENGINE ELECTRICAL SYSTEMS Air filter Spark plug(s) • Clogged air filter element • Incorrect spark plug gap FUEL SYSTEM • Incorrect spark plug heat range Carburetor(s) •...

  • Page 251: Faulty Clutch

    TRBL FAULTY CLUTCH / OVERHEATING SHTG EAS00851 FAULTY CLUTCH CLUTCH SLIPS CLUTCH DRAGS Clutch Clutch • Improperly assembled clutch • Unevenly tensioned clutch springs • Improperly adjusted clutch cable • Warped pressure plate • Loose or fatigued clutch spring • Bent clutch plate •...

  • Page 252: Poor Braking Performance

    TRBL POOR BRAKING PERFORMANCE / FAULTY FRONT FORK LEGS / UNSTABLE HANDLING SHTG EAS00857 POOR BRAKING PERFORMANCE • Worn brake pad • Loose union bolt • Worn brake disc • Damaged brake hose • Air in hydraulic brake system • Oil or grease on the brake disc •...
  • Page 253 YAMAHA MOTOR CO., LTD. 2500 SHINGAI IWATA SHIZUOKA JAPAN...
  • Page 254 YZ85W1 / YZ85(W) / YZ85LW(W) YZ85W1 / YZ85(W) / YZ85LW(W) YZ85W1 / YZ85(W) / YZ85LW(W) 2007 WIRING DIAGRAM 2007 SCHEMA DE CABLAGE SCHALTPLAN 2007 COMPOSANTS ELECTRIQUES Coupe-circuit du moteur B/R G/L G/W W/L Bobine d’allumage G/L B/R W/L B/R G/L Bloc CDI Volant magnétique CDI...
  • Page 255 YZ85W1/YZ85(W)/YZ85LW(W) YZ85W1/YZ85(W)/YZ85LW(W) YZ85W1/YZ85(W)/YZ85LW(W) 2007 WIRING DIAGRAM 2007 SCHEMA DE CABLAGE SCHALTPLAN 2007 COMPOSANTS ELECTRIQUES Coupe-circuit du moteur Bobine d’allumage Bloc CDI Volant magnétique CDI Bougie CODE DE COULEUR B ..Noir O..Orange B/R.

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