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Yamaha RS90K Service Manual

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Download this manual See also: Owner's Manual
SERVICE MANUAL
RS90K
RS90RK
RSG90K
RS90MK
RST90K
RST90TFK
LIT-12618-02-38
8FJ-28197-10
981096

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Summary of Contents for Yamaha RS90K

  • Page 1 SERVICE MANUAL RS90K RS90RK RSG90K RS90MK RST90K RST90TFK LIT-12618-02-38 8FJ-28197-10 981096...
  • Page 2 NOTICE HOW TO USE THIS MANUAL This manual was written by the Yamaha Motor Company primarily for use by Yamaha dealers and Particularly important information is distinguished in their qualified mechanics. It is not possible to put an this manual by the following notations: entire mechanic’s education into one manual, so it...
  • Page 3 ILLUSTRATED SYMBOLS (Refer to the illustration) INSP INFO Illustrated symbols 1 to 9 are designed as thumb tabs to indicate the chapter’s number and content. 1 General information 2 Periodic inspection and adjustment POWR 3 Chassis CHAS 4 Power train 5 Engine 6 Cooling system 7 Carburetion...
  • Page 4 INDEX GENERAL INFORMATION INFO PERIODIC INSPECTION AND INSP ADJUSTMENT CHASSIS CHAS POWER TRAIN POWR ENGINE COOLING SYSTEM COOL CARBURETION CARB – ELECTRICAL ELEC SPECIFICATIONS SPEC...

  • Page 5: Table Of Contents

    CHAPTER 1. POWER TRAIN..........2-25 SHEAVE OFFSET ADJUSTMENT ... 2-25 GENERAL INFORMATION DRIVE V-BELT.......... 2-27 ENGAGEMENT SPEED CHECK....2-29 PARKING BRAKE ADJUSTMENT.... 2-30 MACHINE IDENTIFICATION......1-1 BRAKE FLUID LEVEL INSPECTION ..2-30 FRAME SERIAL NUMBER ......1-1 BRAKE PAD INSPECTION....... 2-31 ENGINE SERIAL NUMBER......
  • Page 6 FRONT SUSPENSION ........3-18 SLIDE RAIL SUSPENSION......4-42 HANDLING NOTES ........3-20 RS90/RS90R..........4-42 INSPECTION ..........3-20 RSG90 ............4-48 INSTALLATION ........3-21 RS90M ............4-53 RST90 ............4-59 RST90TF........... 4-65 CHAPTER 4. REMOVAL..........4-72 POWER TRAIN INSPECTION ..........4-72 ASSEMBLY..........
  • Page 7 A.C. MAGNETO ROTOR CHAPTER 8. AND STARTER CLUTCH....... 5-37 ELECTRICAL REMOVAL ..........5-38 INSPECTION ..........5-39 INSTALLATION ........5-40 SWITCH INSPECTION ........8-1 SWITCH INSPECTION ....... 8-1 OIL PAN AND OIL PUMP ......5-42 INSPECTING A SWITCH SHOWN REMOVAL ..........5-45 IN THE MANUAL ........
  • Page 8 GRIP WARMER SYSTEM ......8-40 CIRCUIT DIAGRAM........8-40 TROUBLESHOOTING......8-42 GRIP AND THUMB WARMER COIL ..8-44 THUMB WARMER ADJUSTMENT SWITCH............ 8-44 GRIP WARMER ADJUSTMENT SWITCH............ 8-45 PASSENGER GRIP WARMER (RST90/RST90TF)........8-45 PASSENGER GRIP WARMER SWITCH (RST90/RST90TF)........8-46 PASSENGER GRIP WARMER RELAY (RST90/RST90TF)........

  • Page 9: Chapter 1. General Information

    MACHINE IDENTIFICATION INFO GENERAL INFORMATION MACHINE IDENTIFICATION FRAME SERIAL NUMBER The frame serial number 1 is located on the right-hand side of the frame (just below the front of the seat). ENGINE SERIAL NUMBER The engine serial number 1 is located on the right-hand side of the crank- case.

  • Page 10: Important Information

    ALL REPLACEMENT PARTS We recommend using genuine Yamaha parts for all replacements. Use oil and grease recommended by Yamaha for assembly and adjustments.

  • Page 11: Gaskets, Oil Seals, And O-Rings

    IMPORTANT INFORMATION INFO GASKETS, OIL SEALS, AND O-RINGS 1. All gaskets, seals, and O-rings should be replaced when an engine is overhauled. All gasket surfaces, oil seal lips, and O-rings must be cleaned. 2. Properly oil all mating parts and bearings during reassembly. Apply grease to the oil seal lips.

  • Page 12: Special Tools

    SPECIAL TOOLS INFO SPECIAL TOOLS Some special tools are necessary for a completely accurate tune-up and assembly. Using the correct special tool will help prevent damage that can be caused by the use of improper tools or improvised techniques. NOTE: •...
  • Page 13 SPECIAL TOOLS INFO • Rotor holding puller P/N: YU-33270-B 90890-01362 • Flywheel puller attachment P/N: YM-33282 90890-04089 These tools are used to remove the magneto rotor. • Cooling system tester P/N: YU-24460-01 90890-01325 • Adapter P/N: YU-33984 90890-01352 This tester and its adapter are used for checking the cooling system. •...
  • Page 14 SPECIAL TOOLS INFO • 40 and 50 mm bearing driver P/N: YM-04058 90890-04058 • Mechanical seal installer P/N: YM-04145 90890-04145 These tools are used to install the water pump seal. • Rotor holding tool P/N: YU-01235 90890-01235 This tool is used to hold the camshaft sprocket. •...

  • Page 15: For Power Train Service

    Used to turn the engine mounting bolts when removing/installing engine. ® • Quick gasket P/N: ACC-QUICK-GS-KT • Yamaha bond No. 1215 P/N: 90890-85505 This bond is used to seal two mating surfaces (e.g., crankcase mating sur- faces.) FOR POWER TRAIN SERVICE •...

  • Page 16: For Carburetion Service

    SPECIAL TOOLS INFO • Clutch bushing press P/N: YS-42424 This tool is used for removing and installing the post bushings (primary sheave cap bush, sliding sheave bush and torque cam bush). • Track clip installer P/N: YS-91045-C 90890-01721 This tool is used for installing the track clip. •...
  • Page 17 SPECIAL TOOLS INFO • Engine tachometer P/N: YU-08036-C 90793-80009 This tool is used to check engine speed.

  • Page 18: Periodic Inspection And Adjustment

    INTRODUCTION/ INSP PERIODIC MAINTENANCE CHART PERIODIC INSPECTION AND ADJUSTMENT INTRODUCTION This chapter includes all information necessary to perform recommended inspections and adjustments. These preventive maintenance procedures, if followed, will ensure more reliable machine operation and a longer ser- vice life. In addition, the need for costly overhaul work will be greatly reduced. This information applies to machines already in service as well as new machines that are being prepared for sale.
  • Page 19 INSP PERIODIC MAINTENANCE CHART Every Initial Pre-opera- 1 month or Seasonally Item Remarks tion check 800 km or 3,200 km (Daily) (500 mi) (2,000 mi) (40 hr) (160 hr) Check oil level. Drive chain oil Replace. Check deflection. Initial at 500 km (300 mi) and every 800 km Drive chain Adjust if necessary.

  • Page 20: Engine

    INSP SPARK PLUGS/FUEL LINE INSPECTION ENGINE SPARK PLUGS 1. Remove: • Spark plug caps • Spark plugs 2. Inspect: • Electrodes 1 Damage/wear → Replace the spark plug. • Insulator color 2 3. Measure: • Spark plug gap a Out of specification → Regap. Use a wire thickness gauge.

  • Page 21: Cooling System

    INSP COOLING SYSTEM COOLING SYSTEM Coolant replacement NOTE: The coolant should be changed at least every sea- son. 1. Place the machine on a level surface. 2. Make sure that the carburetor coolant shut-off lever 1 is turned to “ON” a. (for RS90M) 3.
  • Page 22 INSP COOLING SYSTEM 7. Remove: • Rear bumper cover 1 8. Disconnect: • Coolant hoses 2 9. Drain the coolant. NOTE: Lift up the front of the machine to drain the coolant completely. WARNING Coolant is poisonous. It is harmful or fatal if swallowed.
  • Page 23 INSP COOLING SYSTEM 14. Inspect: • Cooling system Decrease of pressure (leaks) → Repair as required. Inspection steps: • Attach the cooling system tester 1 and adapter 2 to the coolant filler 3. Cooling system tester: 90890-01325, YU-24460-01 Adapter: 90890-01352, YU-33984 •...
  • Page 24 INSP COOLING SYSTEM/VALVE CLEARANCE ADJUSTMENT • Install the coolant filler cap. Apply and lock the parking brake. Start the engine and run it at approximately 2,500 ~ 2,700 r/min until the coolant circulates (approxi- mately 3 ~ 5 minutes). The rear heat exchanger will be warm to the touch.

  • Page 25: Valve Clearance Adjustment

    INSP VALVE CLEARANCE ADJUSTMENT 4. Remove: • Cylinder head cover Refer to “CAMSHAFTS” in CHAPTER 5. • Timing mark accessing screw 1 • Crankshaft end accessing screw 2 5. Measure: • Valve clearance Out of specification → Adjust. Valve clearance (cold): Intake valve: 0.15 ~ 0.22 mm (0.0059 ~ 0.0087 in)
  • Page 26 INSP VALVE CLEARANCE ADJUSTMENT È Front For each cylinder, starting with cylinder #3 at TDC, turn the crankshaft clockwise as specified in the fol- lowing table. É Degrees that the crankshaft is turned clockwise Ê Cylinder Ë Combustion cycle #2 Cylinder 120°...
  • Page 27 INSP VALVE CLEARANCE ADJUSTMENT • Select the proper valve pad from the following table. Valve pad thickness Available valve pads range 1.20 ~ 25 thicknesses in Nos. 2.40 mm 0.05 mm (0.0020 in) 120 ~ 240 (0.047 ~ increments 0.094 in) NOTE: •...
  • Page 28 INSP VALVE CLEARANCE ADJUSTMENT VALVE PAD SELECTION TABLE INTAKE Measured INSTALLED PAD NUMBER clearance ↓ 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240 0.00 ~ 0.04 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 0.05 ~ 0.09...
  • Page 29 INSP VALVE CLEARANCE ADJUSTMENT • Install the new valve pad 1 and the valve lifter NOTE: • Apply molybdenum disulfide oil to the valve pad and the valve lifter. • The valve lifter must turn smoothly when rotated by hand. •...

  • Page 30: Carburetor Synchronization

    INSP CARBURETOR SYNCHRONIZATION CARBURETOR SYNCHRONIZATION NOTE: Prior to synchronizing the carburetors, the valve clearance and the engine idle speed should be properly adjusted. 1. Remove: • Vacuum cap 1 2. Disconnect: • Vacuum hoses 2 3. Install: • T-joint • Vacuum gauge 1 •...

  • Page 31: Engine Idle Speed Adjustment

    CARBURETOR SYNCHRONIZATION/ INSP ENGINE IDLE SPEED ADJUSTMENT Adjustment steps: • Synchronize carburetor #3 to carburetor #2 by turning the synchronizing screw 1 in either direction until both gauges read the same. NOTE: After each step, rev the engine two or three times, each time for less than a second, and check the synchronization again.

  • Page 32: Throttle Cable Free Play Adjustment

    ENGINE IDLE SPEED ADJUSTMENT/ INSP THROTTLE CABLE FREE PLAY ADJUSTMENT 3. Measure: • Engine idle speed Out of specification → Adjust. Engine idle speed: 1,300 ~ 1,500 r/min 4. Adjust: • Engine idle speed Adjustment steps: • Turn the throttle stop screw 1 in or out until the specified engine idle speed is obtained.

  • Page 33: Throttle Override System (T.o.r.s.) Check

    THROTTLE CABLE FREE PLAY ADJUSTMENT/ INSP THROTTLE OVERRIDE SYSTEM (T.O.R.S.) CHECK • Tighten the locknut. NOTE: After adjusting the free play, turn the handlebar to right and left, and make sure that the engine idling does not run faster. THROTTLE OVERRIDE SYSTEM (T.O.R.S.) CHECK WARNING When checking T.O.R.S.:...

  • Page 34: Compression Pressure Measurement

    INSP COMPRESSION PRESSURE MEASUREMENT COMPRESSION PRESSURE MEASUREMENT NOTE: Insufficient compression pressure will result in a loss of performance. 1. Measure: • Valve clearance Out of specification → Adjust. Refer to “VALVE CLEARANCE ADJUST- MENT”. 2. Start the engine, warm it up for several minutes, and then turn it off.

  • Page 35: Engine Oil Level Inspection

    COMPRESSION PRESSURE MEASUREMENT/ INSP ENGINE OIL LEVEL INSPECTION Compression pressure (at sea level): Standard: 1,450 kPa (14.5 kg/cm , 206 psi) at 400 r/min Minimum: 1,260 kPa (12.6 kg/cm , 179 psi) at 400 r/min Maximum: 1,620 kPa (16.2 kg/cm , 230 psi) at 400 r/min Measurement steps:...
  • Page 36 INSP ENGINE OIL LEVEL INSPECTION Inspection steps: • Place the snowmobile on a level surface and apply the parking brake. • Start the engine, warm it up for 10 ~ 15 minutes, and then turn off. • Disconnect the oil level switch coupler 1. CAUTION: Disconnect the oil level switch coupler before removing the oil level gauge.

  • Page 37: Engine Oil Replacement

    ENGINE OIL LEVEL INSPECTION/ INSP ENGINE OIL REPLACEMENT • Check the engine oil level again. NOTE: Before checking the engine oil level, wait a few minutes until the oil has settled. CAUTION: • Use only 4-stroke engine oil. • Engine oil also lubricates the starter clutch. In order to prevent clutch slippage, do not mix any chemical additives with the oil or use oils of a higher grade than “CD”.
  • Page 38 INSP ENGINE OIL REPLACEMENT 8. Remove: • Cylinder head cap 1 9. Remove: • Oil pan drain bolt 1 NOTE: ” mark a is stamped the oil pan near the oil A “ pan drain bolt. 10. Remove: • Oil tank engine oil drain bolt 1 11.
  • Page 39 INSP ENGINE OIL REPLACEMENT 13. Install: • Drain bolts (along with the new gaskets) Oil tank drain bolt: 16 Nm (1.6 m · kg, 12 ft · lb) Oil pan drain bolt: 10 Nm (1.0 m · kg, 7.2 ft · lb) 14.

  • Page 40: Crankcase Breather Hose Inspection

    CRANKCASE BREATHER HOSE INSPECTION/ INSP CARBURETOR JOINTS INSPECTION/ CHECKING THE AIR FILTER ELEMENT CRANKCASE BREATHER HOSE INSPECTION 1. Inspect: • Crankcase breather hose 1 Cracks/damage → Replace. Loosen connection → Connect properly. CAUTION: Make sure that the crankcase breather hose is routed correctly.

  • Page 41: Checking The Air Filter Element

    CHECKING THE AIR FILTER ELEMENT/ INSP EXHAUST SYSTEM INSPECTION 5. Install: • Air filter element • Air filter • Air filter case cover EXHAUST SYSTEM INSPECTION 1. Remove: • Seat • Fuel tank Refer to “SEAT AND FUEL TANK” in CHAP- TER 5.

  • Page 42: Power Train

    INSP SHEAVE OFFSET ADJUSTMENT POWER TRAIN SHEAVE OFFSET ADJUSTMENT 1. Lift up the shroud. 2. Remove: • Left side cover Refer to “PRIMARY SHEAVE AND DRIVE V- BELT” in CHAPTER 4. 3. Remove: • Drive V-belt 4. Measure: • Sheave offset a Use a straightedge that is approximately 470 mm (18.5 in) long, 20 mm (0.79 in) wide, and 4 mm (0.16 in) thick.
  • Page 43 INSP SHEAVE OFFSET ADJUSTMENT • Install the secondary sheave, bolt (secondary sheave) and washer. Bolt (secondary sheave): 64 Nm (6.4 m · kg, 46 ft · lb) • Recheck the sheave offset. If out of specifica- tion, repeat the above steps. NOTE: When adjusting the sheave offset, the secondary sheave free play (clearance) should be adjusted.

  • Page 44: Drive V-Belt

    INSP DRIVE V-BELT DRIVE V-BELT WARNING When installing the new V-belt, make sure that it is positioned from 1.5 mm (0.06 in) above the edge of the secondary sheave to –0.5 mm (–0.02 in) below the edge a. If the V-belt is not positioned correctly, the clutch engagement speed will be changed.
  • Page 45 INSP DRIVE V-BELT 2. Adjust the position of the V-belt by removing or adding a spacer 1 on each adjusting bolt 2. V-belt position Adjustment More than 1.5 mm (0.06 in) above the Remove a spacer edge From 1.5 mm (0.06 in) above the edge to Not necessary –0.5 mm (–0.02 in)

  • Page 46: Engagement Speed Check

    INSP DRIVE V-BELT/ENGAGEMENT SPEED CHECK 6. Measure: • Drive V-belt circumference a Out of specification → Replace. V-belt circumference: 1,129 ~ 1,137 mm (44.4 ~ 44.8 in) ENGAGEMENT SPEED CHECK 1. Place the machine on a level surface of hard- packed snow.

  • Page 47: Parking Brake Adjustment

    PARKING BRAKE ADJUSTMENT/ INSP BRAKE FLUID LEVEL INSPECTION PARKING BRAKE ADJUSTMENT 1. Measure: • Parking brake cable distance a Out of specification → Adjust. Parking brake cable distance: 43.5 ~ 46.5 mm (1.713 ~ 1.831 in) 2. Adjust: • Parking brake cable Adjustment steps: •...

  • Page 48: Brake Pad Inspection

    BRAKE FLUID LEVEL INSPECTION/ INSP BRAKE PAD INSPECTION/BRAKE HOSE INSPECTION NOTE: For a correct reading of the brake fluid level, make sure that the top of the handlebar brake master cyl- inder reservoir is horizontal. CAUTION: Brake fluid may corrode painted surfaces or plastic parts.

  • Page 49: Air Bleeding (Hydraulic Brake System)

    INSP AIR BLEEDING (HYDRAULIC BRAKE SYSTEM) AIR BLEEDING (HYDRAULIC BRAKE SYSTEM) WARNING Bleed the brake system in the following cases: • The system has been disassembled. • A brake hose is loosened or removed. • The brake fluid has been very low. •...

  • Page 50: Drive Chain

    INSP DRIVE CHAIN DRIVE CHAIN Oil level inspection WARNING The engine and muffler will be very hot after the engine has run. Avoid touching a hot engine and muffler while they are still hot with any part of your body or clothing during inspection or repair.
  • Page 51 INSP DRIVE CHAIN • Reinstall the dipstick 1. NOTE: Align the notch a of the dipstick handle with the projection b of the drive chain housing. Oil replacement Oil replacement steps: • Place the oil pan under the drain hole. •...

  • Page 52: Track Tension Adjustment

    INSP TRACK TENSION ADJUSTMENT TRACK TENSION ADJUSTMENT WARNING A broken track or track fittings, and debris thrown by the track could be dangerous to an operator or by standers. Observe the following precautions. • Do not allow anyone to stand behind the machine when the engine is running.
  • Page 53 INSP TRACK TENSION ADJUSTMENT d. Check the track alignment with the slide runner 2. If the alignment is incorrect, turn the left and right adjusters to adjust. È É Track alignment Shifted to Shifted to right left 3 Left adjuster Turn out Turn in 4 Right adjuster...

  • Page 54: Slide Runner Inspection

    SLIDE RUNNER INSPECTION/ INSP MAXIMIZING DRIVE TRACK LIFE SLIDE RUNNER INSPECTION 1. Inspect: • Slide runner 1 Cracks/damage/wear → Replace. 2. Measure: • Slide runner thickness a Out of specification → Replace. Slide runner wear limit: RS90/RS90R/RS90M/RST90/ RST90TF: 10.5 mm (0.41 in) RSG90: 10 mm (0.39 in) È...
  • Page 55 To minimize possible damage, consult your stud man- ufacturer for installation and stud pattern recom- mendations. Yamaha does not recommend track studding. 2-38...

  • Page 56: Chassis

    INSP SKI/SKI RUNNER CHASSIS SKI/SKI RUNNER 1. Inspect: • Ski • Ski runner Damage/wear → Replace. • Ski runner thickness a • Plastic ski thickness b Out of specification → Replace. Ski runner wear limit: 8 mm (0.31 in) Plastic ski wear limit: RS90/RS90R: 12 mm (0.47 in) RS90M/RSG90/RST90/RST90TF:...

  • Page 57: Steering System

    INSP STEERING SYSTEM STEERING SYSTEM Free play check 1. Check: • Steering system free play Move the handlebar up and down and back and forth. Turn the handlebar slightly to the right and left. Excessive free play → Check that the handle- bar, tie rod ends and relay rod ends are installed securely in position.
  • Page 58 INSP STEERING SYSTEM/LUBRICATION 3. Adjust: È • Ski toe-out Adjustment steps: • Loosen the locknuts (tie-rods) 1. • Turn the tie rods 2 in or out until the specified toe-out is obtained. • Tighten the locknuts (tie-rods) 1. Tie-rod end locknut: 25 Nm (2.5 m ·...

  • Page 59: Lubrication

    INSP LUBRICATION È Front and rear suspension 1. Use a grease gun to inject grease into the nip- ples 1. 2. Apply grease to the pivoting parts. Recommended lubricant: ESSO Beacon 325 Grease or Aeroshell Grease #7A È Front É Rear (RS90/RS90R) Ê...
  • Page 60 INSP LUBRICATION Ë Ì Í Ë Rear (RS90M) Ì Rear (RST90) Í Rear (RST90TF) 1 Nipple 2-43...

  • Page 61: Electrical

    HEADLIGHT BEAM ADJUSTMENT/ INSP BATTERY INSPECTION ELECTRICAL HEADLIGHT BEAM ADJUSTMENT 1. Place the machine on a level surface. 2. Place the machine in front of a wall at the rec- ommended distance D. Refer to the table below. 3. Measure the distance H from the floor to the center of the headlight and place a mark on the wall at that height.
  • Page 62 INSP BATTERY INSPECTION First aid in case of bodily contact: External • SKIN – Wash with water. • EYES – Flush with water for 15 minutes and get immediate medical attention. Internal • Drink large quantities of water or milk fol- lowed with milk of magnesia, beaten egg or vegetable oil.
  • Page 63 INSP BATTERY INSPECTION 4. Loosen the joint clamp screws 1. 5. Disconnect: • Oil cut valve outlet hose 1 6. Disconnect: • Crankcase breather hose 1 (engine side) 7. Lift up the air filter case, disconnect the crank- case breather hose 1 from the air filter case. 8.
  • Page 64 INSP BATTERY INSPECTION 9. Disconnect: • Battery leads (from the battery terminals) CAUTION: First, disconnect the negative battery lead 1, then the positive battery lead 2. 10. Remove: • Battery 11. Inspect: • Battery charge Inspection steps: • Connect a pocket tester to the battery terminals. Positive tester probe →...
  • Page 65 INSP BATTERY INSPECTION 12. Charge: • Battery (refer to the appropriate charging method illustration) WARNING Do not quick charge a battery. CAUTION: • Make sure that the battery vent is free of obstructions. • Never remove the MF battery sealing caps. •...
  • Page 66 INSP BATTERY INSPECTION Charging method using a variable voltage charger Charger AMP meter NOTE: Measure the open-circuit Voltage should be measured 30 voltage prior to charging. minutes after the machine is stopped. Connect a charged and NOTE: AMP meter to the battery Set the charging voltage at 16 ~ 17 V.
  • Page 67 INSP BATTERY INSPECTION Charging method using a constant voltage charger NOTE: Voltage should be measured 30 Measure the open-circuit minutes after the machine is voltage prior to charging. stopped. Connect a charger and AMP meter to the battery and start charging. Make sure that the current is higher than the stan- dard charging current writ-...
  • Page 68 INSP BATTERY INSPECTION 13. Install: • Battery 14. Connect: • Battery leads (to the battery terminals) CAUTION: First, connect the positive battery lead 1, then the negative battery lead 2. 15. Check: • Battery terminals Dirt → Clean with a wire brush. Loose connection →...

  • Page 69: Fuse Inspection

    INSP FUSE INSPECTION FUSE INSPECTION The following procedure applies to all of the fuses. CAUTION: To avoid a short circuit, always set the main switch to “OFF” when checking or replacing a fuse. 1. Inspect: • Continuity Inspection steps: • Connect the pocket tester to the fuse and check the continuity.
  • Page 70 INSP FUSE INSPECTION 2. Replace: • Blown fuse Replacing steps: • Set the main switch to “OFF”. • Install a new fuse of the correct amperage. • Set the main switch to “ON” and verify if the electrical circuit is operational. •...

  • Page 71: Speedometer Unit Inspection

    INSP SPEEDOMETER UNIT INSPECTION SPEEDOMETER UNIT INSPECTION 1. Inspect: • Speedometer unit Inspection steps: • Check that the main switch is set to “OFF”, the thumb warmer adjustment switch is pressed, and the speedometer unit, headlights, and taillights are off. •...

  • Page 72: Tuning

    INSP CARBURETOR TUNING TUNING CARBURETOR TUNING The carburetors are set at the factory to run at tem- peratures of 0 °C ~ –20 °C (32 °F ~ –4 °F) at sea level. If the machine is to be operated under condi- tions other than those specified above, the carbure- tors must be properly adjusted.
  • Page 73 NOTE: These jetting specifications are subject to change. Consult the latest technical information from Yamaha to be sure you have the most up-to-date jetting specifications. 1 Pilot screw 2 Main jet 3 Pilot jet...
  • Page 74 INSP CARBURETOR TUNING Guide for carburetion 2-57...
  • Page 75 INSP CARBURETOR TUNING A Standard main jet B Main jet whose diameter is 10% smaller than stan- dard C Main jet whose diameter is 10% larger than standard CAUTION: If the air filter case is removed from the carbu- retors, the change in pressure in the intake will create a lean mixture that may cause severe engine damage.
  • Page 76 INSP CARBURETOR TUNING Engine idle speed: 1,300 ~ 1,500 r/min 3. If low-speed performance is still poor at higher elevations under extreme conditions, the stan- dard pilot jets may need to be replaced. In this way, the proper air/fuel mixture is obtained. NOTE: In this case, use a larger numbered pilot jet to enrich the air/fuel mixture.
  • Page 77 INSP CARBURETOR TUNING Main jet selection chart Spark plug color Diagnosis Remedy Light tan or gray Carburetors are tuned prop- erly. Dry black or fluffy Mixture is too rich. Replace the main jet with the next smaller size. deposits White or light gray Mixture is too lean.
  • Page 78 INSP CARBURETOR TUNING Trouble Diagnosis Adjustment Poor performance at Clogged air vent Remove the air vent hose and clean it. normal speeds: Clogged or loose main jet • Remove the main jet, clean it with compressed • Excessive fuel con- air, and then install it.

  • Page 79: Clutch

    INSP CLUTCH CLUTCH G Green O Orange P Pink High altitude S Silver Y Yellow Specifications Model: RS90/RS90R ~ 800 m 600 ~ 1,400 m 1,200 ~ 2,000 m 1,800 ~ 2,600 m 2,400 ~ 3,000 m È Elevation (~ 2,500 ft) (2,000 ~ 4,500 ft) (4,000 ~ 6,500 ft) (6,000 ~ 8,500 ft)
  • Page 80 INSP CLUTCH G Green L Blue P Pink W White Specifications Model: RSG90 ~ 800 m 600 ~ 1,400 m 1,200 ~ 2,000 m 1,800 ~ 2,600 m 2,400 ~ 3,000 m È Elevation (~ 2,500 ft) (2,000 ~ 4,500 ft) (4,000 ~ 6,500 ft) (6,000 ~ 8,500 ft) (8,000 ~ 10,000 ft)
  • Page 81 INSP CLUTCH G Green P Pink W White Specifications Model: RS90M ~ 800 m 600 ~ 1,400 m 1,200 ~ 2,000 m 1,800 ~ 2,600 m 2,400 ~ 3,000 m È Elevation (~ 2,500 ft) (2,000 ~ 4,500 ft) (4,000 ~ 6,500 ft) (6,000 ~ 8,500 ft) (8,000 ~ 10,000 ft) ←...
  • Page 82 INSP CLUTCH P Pink S Silver W White Y Yellow Specifications Model: RST90 “USA/Canada” ~ 800 m 600 ~ 1,400 m 1,200 ~ 2,000 m 1,800 ~ 2,600 m 2,400 ~ 3,000 m È Elevation (~ 2,500 ft) (2,000 ~ 4,500 ft) (4,000 ~ 6,500 ft) (6,000 ~ 8,500 ft) (8,000 ~ 10,000 ft)
  • Page 83 INSP CLUTCH G Green P Pink W White Y Yellow Specifications Model: RST90 “Europe”/RST90TF ~ 800 m 600 ~ 1,400 m 1,200 ~ 2,000 m 1,800 ~ 2,600 m 2,400 ~ 3,000 m È Elevation (~ 2,500 ft) (2,000 ~ 4,500 ft) (4,000 ~ 6,500 ft) (6,000 ~ 8,500 ft) (8,000 ~ 10,000 ft)

  • Page 84: Gear Selection

    CLUTCH/ INSP GEAR SELECTION The clutch may require tuning depending upon where the machine will be operated and the desired handling characteristics. The clutch can be tuned by changing the engagement and shifting speeds. Clutch engagement speed is defined as the engine speed at which the machine first begins to move from a complete stop.
  • Page 85 INSP GEAR SELECTION 1 Chain and sprocket part number È Parts name É Teeth & links Ê Parts no. Ë Standard 19 teeth 8FA-17682-90 20 teeth 8FA-17682-00 RS90M/RST90 “Europe”/RST90TF 21 teeth 8FA-17682-10 Ì Drive sprocket RS90/RS90R/RSG90/ 22 teeth 8FA-17682-20 RST90 “USA/Canada” 23 teeth 8FA-17682-30 24 teeth...
  • Page 86 INSP GEAR SELECTION 4 Secondary spring twist angle È Seat É Sheave 10° 40° 70° 100° 20° 50° 80° 110° 30° 60° 90° 120° 5 Torque cam (secondary spring seat) É Effects Ê Part no. Ë Cam angle Ì Identification mark Í...
  • Page 87 INSP GEAR SELECTION 6 Primary spring Ì Spring rate Ð Outside Í Preload Ï Wire gauge Ò Free length Ë Parts No. Î Color Ñ No. of coils Ó Standard N/mm diameter N (kg) mm (in) mm (in) (kg/mm) mm (in) 90501-551L3 19.6 (2.00) 294 (30)
  • Page 88 INSP GEAR SELECTION 7 Clutch weight É Weight g (oz) È Parts No. Ê Shape & ID mark Ë Standard without bush and rivets 8BU-17605-20 45.41 (1.603) RS90M 8CH-17605-10 35.32 (1.246) 8DG-17605-00 34.26 (1.208) 8DJ-17605-00 37.77 (1.332) 8DN-17605-10 39.76 (1.402) 8EK-17605-00 39.00 (1.376) RS90/RS90R/...
  • Page 89 INSP GEAR SELECTION 8 Weight rivets Ê Length Ë Weight È Parts No. É Material Ì Standard Í Effects mm (in) g (oz) IN: RST90/RST90TF Î Increased force 90261-06033 Steel 17.2 (0.677) 4.5 (0.159) OUT: RSG90/RST90 “Europe”/ RST90TF IN, OUT: RS90/RS90R 90261-06034 Steel 13.9 (0.547)

  • Page 90: High Altitude Tuning

    INSP HIGH ALTITUDE TUNING HIGH ALTITUDE TUNING To attain the best performance in high altitude conditions, carefully tune the snowmobile as outlined below. Check STD settings • Carburetors • Spark plugs Adjust the main jet size according to the chart Test the main jet Adjust the size of the main jet Not OK...

  • Page 91: Front Suspension

    INSP FRONT SUSPENSION FRONT SUSPENSION È Spring preload 1. Adjust: • Spring preload Adjustment steps: • Turn the spring seat 1 in or out. RS90/RS90R/RSG90 Standard Spring seat Shorter ← → Longer distance Harder ← → Softer Preload Min. Max. Length a 220 mm 230 mm...
  • Page 92 INSP FRONT SUSPENSION/REAR SUSPENSION CAUTION: Be sure that the left and right spring preloads are the same. WARNING These shock absorber contain highly pressur- ized nitrogen gas. Do not tamper with or attempt to open the shock absorber assemblies. Do not subject the shock absorber assemblies to flames or high heat, which could cause it to explode.

  • Page 93: Rear Suspension

    INSP REAR SUSPENSION Choosing other settings: CAUTION: The standard settings work well under most general riding conditions. The suspension can be adjusted to work better in one condition, but only at the expense of another. Keep this in mind when you adjust the suspension. No.
  • Page 94 INSP REAR SUSPENSION Spring preload È 1. Adjust: • Spring preload Adjustment step: Front side • Turn the spring seat 1 in or out. RS90/RS90R “USA/Canada” Standard Spring seat Shorter ← → Longer distance Harder ← → Softer Preload Min. Max.
  • Page 95 INSP REAR SUSPENSION • Turn the adjusting ring 2 to the proper position. É RS90M/RST90 “USA/Canada”/RST90TF Spring adjuster position Softer ← → Harder Preload Standard RST90 “Europe” Spring adjuster position Softer ← → Harder Preload Standard WARNING This shock absorber contains highly pressur- ized nitrogen gas.
  • Page 96 INSP REAR SUSPENSION 2. Adjust: • Extension spring preload Adjustment steps: • Turn the adjusting nut 1 in or out. RST90TF Adjusting nut Turn in Turn out Preload Harder Softer Snow condition Soft Standard length a 16 ~ 18 mm (0.63 ~ 0.71 in) CAUTION: Be sure the left and right spring preload is same.
  • Page 97 INSP REAR SUSPENSION Rear suspension full rate (RSG90) 1. Adjust: • Full rate adjuster Adjustment steps: Installation position Spring rate and Soft Medium Hard damping Standard NOTE: Be sure to make this adjustment when there is no load (rider or cargo) on the snowmobile. •...
  • Page 98 INSP REAR SUSPENSION Control rod 1. Check: • Control rod bolt a (RSG90) Control rod bolt: 32 Nm (3.2 m · kg, 23 ft · lb) 2. Adjust: È • Control rod stroke a CAUTION: Make sure the adjusting bolt ends are set at the same position on each side.
  • Page 99 INSP REAR SUSPENSION Anti-bottoming stopper (RS90/RS90R) 1. Adjust: • Anti-bottoming stopper position 1 CAUTION: Make sure that the anti-bottoming stoppers are installed in the same location on both sides. Anti-bottoming stopper position Spring force Soft Medium Hard Standard NOTE: Be sure to make this adjustment when there is no load (rider or cargo) on the snowmobile.

  • Page 100: Chapter 3. Chassis

    CHAS STEERING CHASSIS STEERING RS90/RS90R/RSG90/RST90/RST90TF Order Job name/Part name Q’ty Remarks Handlebar removal Remove the parts in the order listed below. Handlebar cover Plastic band Thumb warmer lead coupler Disconnect. Thumb warmer adjustment switch lead Disconnect. coupler Engine stop switch coupler Disconnect.
  • Page 101 CHAS STEERING Order Job name/Part name Q’ty Remarks Master cylinder assembly NOTE: Handlebar holder (upper) After installing all parts, refer to “CABLE Cable holder ROUTING” in CHAPTER 9, to check the Handlebar cable and lead routings. Handlebar holder (lower) For installation, reverse the removal proce- dure.

  • Page 102: Rs90M

    CHAS STEERING RS90M Order Job name/Part name Q’ty Remarks Handlebar removal Remove the parts in the order listed below. Handlebar cover Plastic band Thumb warmer lead coupler Disconnect. Thumb warmer adjustment switch lead Disconnect. coupler Engine stop switch coupler Disconnect. Throttle switch coupler Disconnect.
  • Page 103 CHAS STEERING Q’ty Remarks Order Job name/Part name Master cylinder assembly NOTE: Handlebar holder (upper) After installing all parts, refer to “CABLE Cable holder ROUTING” in CHAPTER 9, to check the Handlebar cable and lead routings. Handlebar holder (lower) Steering joint For installation, reverse the removal proce- dure.
  • Page 104 CHAS STEERING Q’ty Remarks Order Job name/Part name Steering column and tie rod removal Remove the parts in the order listed below. Fuel tank Refer to “SEAT AND FUEL TANK” in CHAP- TER 5. Oil tank Refer to “OIL TANK” in CHAPTER 5. Shift lever assembly Refer to “DRIVE CHAIN HOUSING”...
  • Page 105 CHAS STEERING Q’ty Remarks Order Job name/Part name Tie rod NOTE: Remove the tie rod and the parts listed there- after after removing the engine. Idler arm Clip Washer Washer Relay arm Bushing Collar For installation, reverse the removal proce- dure.

  • Page 106: Removal

    CHAS STEERING REMOVAL 1. Straighten the lock washer tabs. INSPECTION 1. Inspect: • Handlebar 1 (RS90/RS90R/RSG90/RST90/ RST90TF) • Handlebar 2 (RS90M) • Steering column 1 3 • Steering column 2 4 Bends/cracks/damage → Replace. WARNING Do not attempt to straighten a bent column. This may dangerously weaken the column.

  • Page 107: Installation

    CHAS STEERING 4. Check: • Rod end movement Rod end free play exists → Replace the rod end. Rod end turns roughly → Replace the rod end. 5. Inspect: • Right relay arm 1 • Left relay arm 2 • Idler arm 3 Cracks/damage →...
  • Page 108 CHAS STEERING 3. Install: • Tie rod 1 • Locknuts 2 • Joints 3 È Tie rod part É Set length Ê Tie rod length b number 8ES-23830-00 (RS90/RS90R/ 424.0 mm 361.0 mm RSG90/RST90/ (16.70 in) (14.21 in) RST90TF) È É...
  • Page 109 CHAS STEERING 7. Install: • Steering shaft 1 • Locknuts 2 • Joints 3 È Steering Shaft É Set length Ê Shaft length b part number 8FA-23840-00 227.8 mm 169.8 mm (8.9685 in) (6.6850 in) NOTE: Install the silver-colored end of the joint 3 to the steering column 1.
  • Page 110 CHAS STEERING 9. Install: • Handlebar CAUTION: • Be sure the projection on the handlebar is not installed into the area a shown. • Be sure the side of the holder with the small gap b faces forward. • First tighten the bolts on the front side of the handlebar holder, and then tighten the bolts on the rear side.

  • Page 111: Ski

    CHAS RS90/RS90R/RSG90 “USA/Canada” Order Job name/Part name Q’ty Remarks Ski removal Remove the parts in the order listed below. Cotter pin Bolt Collar Ski stopper For installation, reverse the removal proce- dure. 3-12...

  • Page 112: Rsg90 "Europe"/Rst90 "Europe"/Rst90Tf

    CHAS RSG90 “Europe”/RST90 “Europe”/RST90TF Order Job name/Part name Q’ty Remarks Ski removal Remove the parts in the order listed below. Cotter pin Bolt Collar For RSG90 “Europe”/RST90 “Europe”/ RST90TF Collar Ski stopper Ski stopper plate For RSG90 “Europe”/RST90 “Europe”/ RST90TF For installation, reverse the removal proce- dure.

  • Page 113: Rs90M

    CHAS RS90M Order Job name/Part name Q’ty Remarks Ski removal Remove the parts in the order listed below. Cotter pin Bolt Collar For RS90M Collar Ski stopper For installation, reverse the removal proce- dure. 3-14...

  • Page 114: Rst90 "Usa/Canada

    CHAS RST90 “USA/Canada” Order Job name/Part name Q’ty Remarks Ski removal Remove the parts in the order listed below. Cotter pin Bolt Collar Ski stopper For installation, reverse the removal proce- dure. 3-15...

  • Page 115: Inspection

    CHAS INSPECTION È 1. Inspect: • Ski 1 • Ski runner 2 • Ski stopper 3 • Ski stopper plate 4 (RS90M/RST90 “Europe”/RST90TF) • Ski column lower bracket 5 (RST90) • Ski handle 6 Wear/cracks/damage → Replace. • Mounting bolt 7 •...

  • Page 116: Installation (Rst90 "Usa/Canada")

    CHAS Ê Ë INSTALLATION (RST90 “USA/Canada”) 1. Install: • Ski column lower bracket 1 NOTE: Be sure to install the ski column lower bracket with the arrow mark a pointing forward the tip of the ski. 3-17...

  • Page 117: Front Suspension

    CHAS FRONT SUSPENSION FRONT SUSPENSION Q’ty Remarks Order Job name/Part name Front suspension removal Remove the parts in the order listed below. Refer to “SKI”. Front cover Shock absorber Collar Cotter pin Tie rod Disconnect. Steering arm Ski column Bushing Upper arm Lower arm Bushing...
  • Page 118 CHAS FRONT SUSPENSION Q’ty Remarks Order Job name/Part name Stabilizer Bushing Steering knuckle Collar For installation, reverse the removal proce- dure. 3-19...

  • Page 119: Handling Notes

    CHAS FRONT SUSPENSION HANDLING NOTES WARNING RS90/RS90R/RSG90/RS90M This shock absorber contains highly com- pressed nitrogen gas. Before handling the shock absorber read and make sure that you understand the following information. The man- ufacturer cannot be held responsible for prop- erty damage or personal injury that may result from improper handling.

  • Page 120: Installation

    CHAS FRONT SUSPENSION 3. Inspect: • Upper arms 1 • Lower arms 2 Cracks/bends/damage → Replace. • Bushings 3 Wear/scratches/damage → Replace. 4. Inspect: • Connecting rods 1 • Stabilizer 2 • Stabilizer arms 3 Cracks/bends/damage → Replace. • Bushings 4 Wear/scratches/damage →...
  • Page 121 CHAS FRONT SUSPENSION 2. Install: • Stabilizer 1 • Stabilizer arm 2 • Connecting rod 3 NOTE: • The installation angles of the left and right stabi- lizer arms should be within 6° of each other. • Install the connecting rod end with the width a to the stabilizer arm.
  • Page 122 CHAS FRONT SUSPENSION Ski alignment NOTE: Be sure to verify the spring preload setting before adjusting the ski toe-out since this adjustments may affect the ski toe-out setting. Point the skis straight forward and measure the amount of ski toe-out. È...

  • Page 123: Chapter 4. Power Train

    POWR PRIMARY SHEAVE AND DRIVE V-BELT POWER TRAIN PRIMARY SHEAVE AND DRIVE V-BELT Q’ty Remarks Order Job name/Part name Primary sheave removal Remove the parts in the order listed below. Left side cover V-belt Primary sheave assembly For installation, reverse the removal proce- dure.
  • Page 124 POWR PRIMARY SHEAVE AND DRIVE V-BELT Q’ty Remarks Order Job name/Part name Primary sheave disassembly Remove the parts in the order listed below. Primary sheave cap Primary sheave spring Collar Roller Washer Collar Weight Washer Fixed sheave Stopper Sliding sheave Bushing Spider Left-handed thread.

  • Page 125: Removal

    POWR PRIMARY SHEAVE AND DRIVE V-BELT REMOVAL 1. Remove: • Primary sheave assembly 1 NOTE: Use the primary sheave holder 2 and primary sheave puller 3. Sheave holder: 90890-01701, YS-01880-A Primary sheave puller: 90890-01898, YS-01881-A, YS-01881-1 DISASSEMBLY 1. Remove: • Fixed sheave 1 •...

  • Page 126: Inspection

    POWR PRIMARY SHEAVE AND DRIVE V-BELT • Fit the primary sheave assembly onto the adapter and secure the supporting plates 8. NOTE: Securely fit the projections on the adapter into the fixed sheave holes. • Set the bar wrench 9 onto the spider and turn the special tool clockwise to loosen the spider.
  • Page 127 POWR PRIMARY SHEAVE AND DRIVE V-BELT 2. Inspect: • Primary sheave spring 1 Cracks/damage → Replace. 3. Measure: • Primary sheave spring (standard) free length Out of specification → Replace the primary sheave spring. Primary sheave spring (standard) free length: RS90/RS90R: 87.4 mm (3.44 in) RSG90:...

  • Page 128: Assembly

    POWR PRIMARY SHEAVE AND DRIVE V-BELT Rivet replacement steps: • Remove old rivet with the appropriate drill. • Insert the rivet 1 from the ID mark 2 side. • Press or peen the rivet head so that the diame- ter a of the rivet head measures 8.2 mm (0.32 in) or larger.
  • Page 129 POWR PRIMARY SHEAVE AND DRIVE V-BELT 2. Install: • Fixed sheave (onto the spider) NOTE: • Clean the threads. ® • Apply LOCTITE #648 to the fixed sheave as shown. CAUTION: ® LOCTITE should be applied only to the speci- fied area.
  • Page 130 POWR PRIMARY SHEAVE AND DRIVE V-BELT • Tighten the spider to specification using the bar wrench 3. Spider: 200 Nm (20.0 m · kg, 145 ft · lb) CAUTION: The spider has a left-handed thread. WARNING • Do not operate the primary sheave until the ®...

  • Page 131: Installation

    POWR PRIMARY SHEAVE AND DRIVE V-BELT INSTALLATION 1. Install: • Primary sheave assembly CAUTION: Be sure to remove any oil or grease from the tapered portion of the crankshaft and spider using a cloth dampened with thinner. 2. Apply: • Engine oil (to threads of primary sheave bolt) 3.

  • Page 132: Secondary Sheave

    POWR SECONDARY SHEAVE SECONDARY SHEAVE Q’ty Remarks Order Job name/Part name Secondary sheave removal Remove the parts in the order listed below. Left side cover Refer to “PRIMARY SHEAVE AND DRIVE V-BELT”. V-belt Washer Shim – Refer to “SHEAVE OFFSET ADJUSTMENT” in CHAPTER 2.
  • Page 133 POWR SECONDARY SHEAVE Q’ty Remarks Order Job name/Part name Secondary sheave disassembly Remove the parts in the order listed below. Spring seat Secondary sheave spring Fixed sheave Stopper Sliding sheave For assembly, reverse the disassembly pro- cedure. 4-11...

  • Page 134: Disassembly

    POWR SECONDARY SHEAVE DISASSEMBLY WARNING • Use extreme CAUTION when disassembling the secondary sheave since serious injury can occur due to the sudden release of spring tension. Use the sheave compressor to con- tain the spring tension before removing the spring seat nuts.

  • Page 135: Assembly

    POWR SECONDARY SHEAVE 5. Measure: • Ramp shoe thickness a Out of specification → Replace the ramp shoe. Wear limit: 1.0 mm (0.04 in) ASSEMBLY 1. Install: • Stopper Stopper screw: 7 Nm (0.7 m · kg, 5.1 ft · lb) 2.
  • Page 136 POWR SECONDARY SHEAVE Installation steps: • Hold the spring seat 1 and turn the fixed sheave 2 counterclockwise to the specified angle a. NOTE: The holes in the spring seat should align with the bolts on the sliding sheave. a = (sheave hole number + spring seat hole number) ×...

  • Page 137: Installation

    • Install new shims of the proper thickness and reassemble the secondary sheave. • Measure the secondary sheave clearance again. Repeat these steps until the clearance is within specification. NOTE: Yamaha recommends keeping the original shims. Shims: Part number Thickness 90201-061H1 0.5 mm (0.02 in) 90201-06037 1.0 mm (0.04 in)

  • Page 138: Drive Chain Housing

    POWR DRIVE CHAIN HOUSING DRIVE CHAIN HOUSING WITHOUT REVERSE MODEL Order Job name/Part name Q’ty Remarks Drive chain housing removal Remove the parts in the order listed below. Secondary sheave Refer to “SECONDARY SHEAVE”. Right side cover/brake caliper/parking Refer to “BRAKE”. brake Shim —...
  • Page 139 POWR DRIVE CHAIN HOUSING Q’ty Remarks Order Job name/Part name Drive sprocket Collar Driven sprocket Collar Drive chain Drive chain housing For installation, reverse the removal proce- dure. 4-17...

  • Page 140: Removal

    POWR DRIVE CHAIN HOUSING REMOVAL 1. Remove: • Driven sprocket • Drive sprocket Refer to “WITH REVERSE MODEL”. INSPECTION 1. Inspect: • Drive chain housing 1 • Drive chain housing cover 2 Cracks/damage → Replace. • Oil seals (drive chain housing and cover) Wear/damage →...
  • Page 141 POWR DRIVE CHAIN HOUSING 2. Inspect: • Drive sprocket 1 • Driven sprocket 2 • Chain tensioner 3 Pitting/wear/damage → Replace. 3. Measure: • 14 link section a of the drive chain Using a spring scale, pull on the drive chain with 36 kg (80 lb) of force b.

  • Page 142: Installation

    POWR DRIVE CHAIN HOUSING INSTALLATION 1. During installation, pay attention to the follow- ing. È Make sure that the bearing seals face towards the drive chain as shown. É Properly install the rubber seal onto the drive chain É housing, making sure that there are no gaps. Be sure to install the spacers in their original positions, otherwise the brake disc and jack- Ë...

  • Page 143: With Reverse Model

    POWR DRIVE CHAIN HOUSING WITH REVERSE MODEL Order Job name/Part name Q’ty Remarks Drive chain housing removal Remove the parts in the order listed below. Secondary sheave Refer to “SECONDARY SHEAVE”. Right side cover/brake caliper/parking Refer to “BRAKE”. brake Shim —...
  • Page 144 POWR DRIVE CHAIN HOUSING Q’ty Remarks Order Job name/Part name Drive chain housing cover Rubber seal Washer Counter gear Spring Chain tensioner Washer t = 0.5 Collar Collar Spring Reverse driven gear Journal Washer Forward driven sprocket Collar Reverse drive gear Washer Drive chain 4-22...
  • Page 145 POWR DRIVE CHAIN HOUSING Q’ty Remarks Order Job name/Part name Drive sprocket Collar Plate Shaft Drive chain housing For installation, reverse the removal proce- dure. 4-23...

  • Page 146: Removal

    POWR DRIVE CHAIN HOUSING REMOVAL 1. Remove: • Reverse driven gear 1 (driven sprocket for without reverse model) NOTE: While holding the front axle assembly with spanner wrench 2, loosen the reverse driven gear bolt. 2. Remove: • Drive sprocket 1 NOTE: While holding the secondary shaft with the second- ary shaft slide &...

  • Page 147: Installation

    POWR DRIVE CHAIN HOUSING 2. Inspect: • Drive sprocket 1 • Forward driven sprocket 2 • Reverse driven gear 3 • Reverse drive gear 4 • Counter gear 5 • Journal 6 • Chain tensioner 7 Pitting/wear/damage → Replace. • Drive chain 8 Wear/damage →...
  • Page 148 POWR DRIVE CHAIN HOUSING 2. Install: • Lever rod 1 3. Adjust: • Lever rod length a Adjustment steps: • Loosen the locknuts 2. • Turn the lever rod 1 in or out until the specified length is obtained. Lever rod length: 27 mm (1.06 in) •...

  • Page 149: Secondary Shaft

    POWR SECONDARY SHAFT SECONDARY SHAFT Q’ty Remarks Order Job name/Part name Secondary shaft removal Remove the parts in the order listed below. Secondary sheave Refer to “SECONDARY SHEAVE”. Drive chain housing Refer to “DRIVE CHAIN HOUSING”. Bearing collar nut Collar Circlip Secondary shaft Bearing...

  • Page 150: Removal

    POWR SECONDARY SHAFT REMOVAL 1. Remove: • Drive chain housing parts Refer to “DRIVE CHAIN HOUSING”. • Secondary sheave assembly Refer to “SECONDARY SHEAVE”. 2. Install: • Secondary shaft slide & holder 1 NOTE: • This procedure does not require the use of the collar 2 included with the special tool.

  • Page 151: Inspection

    POWR SECONDARY SHAFT INSPECTION 1. Inspect: • Secondary shaft 1 Scratches (excessive)/damage → Replace. • Splines 2 Wear/damage → Replace the secondary shaft. • Bearing contact surface 3 Scratches/wear/damage → Replace the sec- ondary shaft. 2. Inspect: • Bearing 1 Pitting/damage →...
  • Page 152 POWR SECONDARY SHAFT 3. Tighten: • Drive sprocket nut 3 Drive sprocket nut: 90 Nm (9.0 m · kg, 65 ft · lb) NOTE: While holding the secondary shaft with the second- ary shaft slide & holder 4, tighten the drive sprocket nut with the drive gear socket 5.
  • Page 153 POWR SECONDARY SHAFT 6. Tighten: • Bearing collar nut 9 Ring nut wrench: 90890-01268, YU-01268 Bearing collar nut: 55 Nm (5.5 m · kg, 40 ft · lb) NOTE: Install the ring nut wrench 0 and then tighten the bearing collar nut. 7.

  • Page 154: Secondary Shaft And Drive Chain Housing Installation

    POWR SECONDARY SHAFT SECONDARY SHAFT AND DRIVE CHAIN HOUSING INSTALLATION 1. Install: • Secondary shaft • Drive chain housing È Installation steps: • Install the secondary shaft. • Install the drive chain housing 1. • Tighten the bolts. Drive chain housing bolt: 48 Nm (4.8 m ·...
  • Page 155 POWR SECONDARY SHAFT 3. Adjust: • Brake disc clearance Adjustment steps: • Remove the circlip 7. • Adjust the brake disc clearance by adding or removing shim(s) 8. Shim size Part number Thickness 90201-252F1 0.5 mm (0.02 in) • Install the new circlip. 4-33...

  • Page 156: Brake

    POWR BRAKE BRAKE Q’ty Remarks Order Job name/Part name Brake pad removal Remove the parts in the order listed below. Right side cover Cap bolt Retaining pin Pad spring Brake pad Brake caliper assembly For installation, reverse the removal proce- dure.

  • Page 157: Brake Pad Replacement

    POWR BRAKE CAUTION: Disc brake components rarely require disas- sembly. DO NOT: • Do not disassemble components unless absolutely necessary. • Do not use solvents on internal brake compo- nents. • Do not use contaminated brake fluid for cleaning. • Use only clean brake fluid. •...
  • Page 158 POWR BRAKE 2. Install: • Brake pads • Pad spring Installation steps: • Connect a suitable hoses 1 tightly to the cali- per bleed screws 2. Put the other end of this hose into an open container. • Loosen the caliper bleed screws and push the pistons into the caliper with your finger.
  • Page 159 POWR BRAKE Q’ty Remarks Order Job name/Part name Brake caliper and parking brake Remove the parts in the order listed below. removal Brake fluid Drain. Brake hose Brake caliper assembly Parking brake cable Spring Parking brake assembly Collar For installation, reverse the removal proce- dure.

  • Page 160: Brake Caliper Disassembly

    POWR BRAKE BRAKE CALIPER DISASSEMBLY NOTE: Before disassembling a caliper, drain brake fluid from brake hose, master cylinder, brake caliper and brake reservoir of their brake fluid. 1. Remove: • Pistons • Piston oil seals 1 Removal steps: • Using a wood of piece 2, lock the right piston. •...

  • Page 161: Brake Caliper Assembly

    POWR BRAKE 1. Inspect: • Caliper piston 1 Scratches/rust/wear → Replace the caliper assembly. • Caliper cylinder 2 → Wear/scratches Replace caliper assembly. • Caliper body 3 Cracks/damage → Replace. • Oil delivery passage (caliper body) Blow out with compressed air. WARNING Replace the piston seals and dust seals when- ever a caliper is disassembled.
  • Page 162 POWR BRAKE Q’ty Remarks Order Job name/Part name Brake master cylinder removal Remove the parts in the order listed below. Brake fluid Drain. Parking brake cable Disconnect. Brake switch Brake lever Parking brake lever Union bolt Holder Master cylinder assembly For installation, reverse the removal proce- dure.

  • Page 163: Inspection

    POWR BRAKE INSPECTION 1. Inspect: • Master cylinder 1 Wear/scratches → Replace the master cylin- der assembly. • Master cylinder body 2 Cracks/damage → Replace. • Oil delivery passage (master cylinder body) Blow out with compressed air. 2. Inspect: • Master cylinder kit 1 Scratches/wear/damage →...

  • Page 164: Slide Rail Suspension

    POWR SLIDE RAIL SUSPENSION SLIDE RAIL SUSPENSION RS90/RS90R Order Job name/Part name Q’ty Remarks Slide rail suspension removal Remove the parts in the order listed below. Rear axle nut Loosen. Tension adjuster Loosen. Slide rail suspension For installation, reverse the removal proce- dure.
  • Page 165 POWR SLIDE RAIL SUSPENSION È: 4 Nm (0.4 m kg, 2.9 ft • • É: 49 Nm (4.9 m kg, 35 ft • • Ê: kg, 43 ft 60 Nm (6.0 m • • Ë: kg, 80 ft 110 Nm (11.0 m •...
  • Page 166 POWR SLIDE RAIL SUSPENSION È È: kg, 4.3 ft 6 Nm (0.6 m • • É: kg, 43 ft 60 Nm (6.0 m • • Ê: kg, 52 ft 72 Nm (7.2 m • • É Ê É É È É...
  • Page 167 POWR SLIDE RAIL SUSPENSION Ê É Ë Ì Ê Ì È È: kg, 6.5 ft 9 Nm (0.9 m • • É: kg, 18 ft 25 Nm (2.5 m • • Ê: kg, 35 ft 49 Nm (4.9 m • •...
  • Page 168 POWR SLIDE RAIL SUSPENSION Ê É Ë Ì Ê Ì È È: kg, 6.5 ft 9 Nm (0.9 m • • É: kg, 18 ft 25 Nm (2.5 m • • Ê: kg, 35 ft 49 Nm (4.9 m • •...
  • Page 169 POWR SLIDE RAIL SUSPENSION È: kg, 54 ft 75 Nm (7.5 m • • È Q’ty Remarks Order Job name/Part name Rear axle Guide wheel Guide wheel Collar Tension adjuster Collar Collar Sliding frame For assembly, reverse the disassembly pro- cedure.

  • Page 170: Rsg90

    POWR SLIDE RAIL SUSPENSION RSG90 Order Job name/Part name Q’ty Remarks Slide rail suspension removal Remove the parts in the order listed below. Rear axle nut Loosen. Tension adjuster Loosen. Left side cover Refer to “PRIMARY SHEAVE AND DRIVE V- BELT”.
  • Page 171 POWR SLIDE RAIL SUSPENSION Q’ty Remarks Order Job name/Part name Slide rail suspension disassembly Remove the parts in the order listed below. Stopper band Hook Bushing Bushing Front shock absorber Bracket Front suspension bracket Shaft Rubber damper Front pivot arm Bushing Shaft Bushing...
  • Page 172 POWR SLIDE RAIL SUSPENSION Q’ty Remarks Order Job name/Part name Suspension wheel Collar Wheel bracket Circlip Suspension wheel Collar Bushing Shaft Rear suspension bracket Spacer Collar Bushing This model has a “Easy adjust” system for the full rate adjuster. The bolt has teeth on it. So when the bolt is turned, it rides up and down the bracket.
  • Page 173 POWR SLIDE RAIL SUSPENSION Q’ty Remarks Order Job name/Part name Rear shock absorber Collar Bushing Pull rod Collar Bushing Collar Suspension wheel Control rod Bushing Bushing 4-51...
  • Page 174 POWR SLIDE RAIL SUSPENSION Q’ty Remarks Order Job name/Part name Rear pivot arm Bushing Shaft Shaft Rear pivot arm bracket Shaft Circlip Suspension wheel Wheel bracket shaft Rear axle Guide wheel Collar Tension adjuster Collar Collar Guide wheel Sliding frame For assembly, reverse the disassembly pro- cedure.

  • Page 175: Rs90M

    POWR SLIDE RAIL SUSPENSION RS90M Order Job name/Part name Q’ty Remarks Slide rail suspension removal Remove the parts in the order listed below. Rear axle nut Loosen. Tension adjuster Loosen. Slide rail suspension For installation, reverse the removal proce- dure. 4-53...
  • Page 176 POWR SLIDE RAIL SUSPENSION È: 4 Nm (0.4 m kg, 2.9 ft • • É: 49 Nm (4.9 m kg, 35 ft • • Ê: kg, 43 ft 60 Nm (6.0 m • • Ë: 70 Nm (7.2 m kg, 54 ft •...
  • Page 177 POWR SLIDE RAIL SUSPENSION È È: kg, 4.3 ft 6 Nm (0.6 m • • É: kg, 43 ft 60 Nm (6.0 m • • Ê: kg, 52 ft 72 Nm (7.2 m • • É Ê É È É É...
  • Page 178 POWR SLIDE RAIL SUSPENSION È: kg, 6.5 ft 9 Nm (0.9 m • • É: kg, 18 ft 25 Nm (2.5 m • • Ê: kg, 35 ft 49 Nm (4.9 m • • Ë: kg, 43 ft 60 Nm (6.0 m •...
  • Page 179 POWR SLIDE RAIL SUSPENSION È: kg, 6.5 ft 9 Nm (0.9 m • • É: kg, 18 ft 25 Nm (2.5 m • • Ê: kg, 35 ft 49 Nm (4.9 m • • Ë: kg, 43 ft 60 Nm (6.0 m •...
  • Page 180 POWR SLIDE RAIL SUSPENSION È: kg, 54 ft 75 Nm (7.5 m • • È Q’ty Remarks Order Job name/Part name Rear axle Guide wheel Guide wheel Collar Tension adjuster Collar Collar Sliding frame For assembly, reverse the disassembly pro- cedure.

  • Page 181: Rst90

    POWR SLIDE RAIL SUSPENSION RST90 È: kg, 52 ft 72 Nm (7.2 m • • È È Order Job name/Part name Q’ty Remarks Slide rail suspension removal Remove the parts in the order listed below. Rear axle nut Loosen. Tension adjuster Loosen.
  • Page 182 POWR SLIDE RAIL SUSPENSION È: 4 Nm (0.4 m kg, 2.9 ft • • É: 49 Nm (4.9 m kg, 35 ft • • Ê: kg, 43 ft 60 Nm (6.0 m • • Ë: 72 Nm (7.2 m kg, 52 ft •...
  • Page 183 POWR SLIDE RAIL SUSPENSION È È: kg, 4.3 ft 6 Nm (0.6 m • • É: kg, 43 ft 60 Nm (6.0 m • • Ê: kg, 52 ft 72 Nm (7.2 m • • Ê É É È É É...
  • Page 184 POWR SLIDE RAIL SUSPENSION È: Ë: kg, 6.5 ft kg, 43 ft 9 Nm (0.9 m 60 Nm (6.0 m • • • • É: Ì: kg, 18 ft kg, 52 ft 25 Nm (2.5 m 72 Nm (7.2 m •...
  • Page 185 POWR SLIDE RAIL SUSPENSION È: Ë: kg, 6.5 ft kg, 43 ft 9 Nm (0.9 m 60 Nm (6.0 m • • • • É: Ì: kg, 18 ft kg, 52 ft 25 Nm (2.5 m 72 Nm (7.2 m •...
  • Page 186 POWR SLIDE RAIL SUSPENSION È: kg, 54 ft 75 Nm (7.5 m • • È Q’ty Remarks Order Job name/Part name Rear axle Guide wheel Collar Collar Guide wheel Collar Tension adjuster Sliding frame For assembly, reverse the disassembly pro- cedure.

  • Page 187: Rst90Tf

    POWR SLIDE RAIL SUSPENSION RST90TF È: kg, 52 ft 72 Nm (7.2 m • • È È Order Job name/Part name Q’ty Remarks Slide rail suspension removal Remove the parts in the order listed below. Rear axle nut Loosen. Tension adjuster Loosen.
  • Page 188 POWR SLIDE RAIL SUSPENSION È: 4 Nm (0.4 m kg, 2.9 ft • • É: 49 Nm (4.9 m kg, 35 ft • • Ê: kg, 43 ft 60 Nm (6.0 m • • Ë: 72 Nm (7.2 m kg, 52 ft •...
  • Page 189 POWR SLIDE RAIL SUSPENSION È È: kg, 4.3 ft 6 Nm (0.6 m • • É: kg, 43 ft 60 Nm (6.0 m • • Ê: kg, 52 ft 72 Nm (7.2 m • • Ê É É È É É...
  • Page 190 POWR SLIDE RAIL SUSPENSION È: 9 Nm (0.9 m kg, 6.5 ft • • É: kg, 18 ft 25 Nm (2.5 m • • Ê: 49 Nm (4.9 m kg, 35 ft • • Ë: kg, 43 ft 60 Nm (6.0 m •...
  • Page 191 POWR SLIDE RAIL SUSPENSION È: 9 Nm (0.9 m kg, 6.5 ft • • É: kg, 18 ft 25 Nm (2.5 m • • Ê: 49 Nm (4.9 m kg, 35 ft • • Ë: kg, 43 ft 60 Nm (6.0 m •...
  • Page 192 POWR SLIDE RAIL SUSPENSION È: kg, 20 ft 28 Nm (2.8 m • • É: kg, 24 ft 34 Nm (3.4 m • • Ê: 64 Nm (6.4 m kg, 46 ft • • Ë: kg, 58 ft 80 Nm (8.0 m •...
  • Page 193 POWR SLIDE RAIL SUSPENSION È: kg, 58 ft 80 Nm (8.0 m • • † ç å £ ¢ £ ¢ È Q’ty Remarks Order Job name/Part name Rear axle Guide wheel Collar å Collar ç Guide wheel † Collar ¢...

  • Page 194: Removal

    POWR SLIDE RAIL SUSPENSION REMOVAL 1. Unhook the torsion spring 1 (Except for RSG90) NOTE: For RS90/RS90R/RS90M Rotate the spring end guide 2 in the direction of the arrow shown to unhook the end of the torsion spring. INSPECTION 1. Inspect: •...

  • Page 195: Assembly

    POWR SLIDE RAIL SUSPENSION 2. Inspect: È • Stopper band 1 Frayed/damage → Replace. • Pull rod 2 Bends/damage → Replace. • Shock absorber 3 Oil leaks/damage → Replace. • Bushings Wear/cracks/damage → Replace. • Front pivot arm 4 • Rear pivot arm 5 •...
  • Page 196 POWR SLIDE RAIL SUSPENSION 2. Install: È • Front shock absorber 1 (RS90/RS90R/ RSG90) • Rear shock absorber 2 (RSG90) • 2-up adjusting block 3 (RST90) NOTE: • For RS90/RS90R: Install the front shock absorber with the charging valve a facing towards the rear of the machine. •...

  • Page 197: Installation

    POWR SLIDE RAIL SUSPENSION 3. Install: È • Stopper band 1 NOTE: • For RSG90: Install the stopper band with a toward the hook and b toward the front suspension bracket. • Except for RSG90: Install the stopper band with a toward the front pivot arm and b toward the shaft.
  • Page 198 POWR SLIDE RAIL SUSPENSION Control rod parts number (for RSG90) È Control rod 1 É Length a mm (in) Ê Length b mm (in) Ë Length c mm (in) 2.5P × 3 = 7.5 RSG90 303.5 (11.95) 160.0 (6.30) (0.098P × 3 = 0.295) Î...
  • Page 199 POWR SLIDE RAIL SUSPENSION Control rod part numbers (except for RSG90) È Control rod 1 É Length a mm (in) Ê Length b mm (in) Ë Length c mm (in) RS90/RS90R 228.8 (9.01) 2.5P × 2 = 5 198.7 (7.80) RS90M/RST90TF 240.3 (9.46) (0.098P ×...

  • Page 200: Front Axle And Track

    POWR FRONT AXLE AND TRACK FRONT AXLE AND TRACK Q’ty Remarks Order Job name/Part name Front axle and track removal Remove the parts in the order listed below. Drive chain housing Refer to “DRIVE CHAIN HOUSING”. Slide rail suspension Refer to “SLIDE RAIL SUSPENSION”. Secondary sheave Refer to “SECONDARY SHEAVE”.

  • Page 201: Inspection

    POWR FRONT AXLE AND TRACK INSPECTION 1. Inspect: • Track 1 • Slide metal 2 Wear/cracks/damage → Replace. 2. Inspect: • Sprocket wheel 1 Wear/break/damage → Replace. • Front axle 2 Bends/scratches (excessive)/damage → Replace. 3. Inspect: • Bearing Pitting/damage → Replace. È...
  • Page 202 POWR FRONT AXLE AND TRACK 2. Place the track in the chassis. È NOTE: For track with a direction of rotation mark a: Install the track with the mark pointing in the direc- tion of track rotation. È RS90/RS90R/RSG90/RST90/RST90TF É RS90M É...

  • Page 203: Chapter 5. Engine

    SEAT AND FUEL TANK ENGINE SEAT AND FUEL TANK RS90/RS90R/RSG90/RS90M Order Job name/Part name Q’ty Remarks Seat and fuel tank removal Remove the parts in the order listed below. Handlebar Refer to “STEERING” in CHAPTER 3. Rear cover Muffler protector Tail/brake light cover Tail/brake light sub-wire harness Disconnect.

  • Page 204: Backrest And Passenger Seat

    BACKREST AND PASSENGER SEAT BACKREST AND PASSENGER SEAT RST90/RST90TF Order Job name/Part name Q’ty Remarks Backrest and passenger seat removal Remove the parts in the order listed below. Carrier assembly Backrest Carrier lock bracket Passenger seat Passenger grip warmer coupler Disconnect.

  • Page 205: Rider Seat And Fuel Tank

    RIDER SEAT AND FUEL TANK RIDER SEAT AND FUEL TANK RST90/RST90TF Order Job name/Part name Q’ty Remarks Rider seat and fuel tank removal Remove the parts in the order listed below. Handlebar Refer to “STEERING” in CHAPTER 3. Passenger seat Refer to “BACKREST AND PASSENGER SEAT”.

  • Page 206: Removal

    RIDER SEAT AND FUEL TANK REMOVAL 1. Remove: • Carrier assembly 1 • Backrest 2 Removal step: • Pull the carrier lock lever 3 away from the car- rier lock bracket 4, and then turn the carrier lock lever to position b to remove the carrier assembly and backrest.

  • Page 207: Oil Tank

    OIL TANK OIL TANK È: 10 Nm (1.0 m kg, 7.2 ft • • É: kg, 13 ft 19 Nm (1.9 m • • È É Q’ty Remarks Order Job name/Part name Oil tank removal Remove the parts in the order listed below. Right side cover Refer to “BRAKE”...

  • Page 208: Engine Assembly

    ENGINE ASSEMBLY ENGINE ASSEMBLY HOSE AND LEADS È: kg, 5.1 ft 7 Nm (0.7 m • • É: 8 Nm (0.8 m kg, 5.8 ft • • 9 10 Ê: kg, 18 ft 25 Nm (2.5 m • • É È...

  • Page 209: Engine Assembly

    ENGINE ASSEMBLY È: kg, 5.1 ft 7 Nm (0.7 m • • É: kg, 5.8 ft 8 Nm (0.8 m • • 9 10 Ê: kg, 18 ft 25 Nm (2.5 m • • É È Ê È Q’ty Remarks Order Job name/Part name A.C.
  • Page 210 ENGINE ASSEMBLY ENGINE ASSEMBLY Ê Ë Ë Î 6 Ì É Î Ë Í Î È: kg, 5.1 ft 7 Nm (0.7 m • • È É: 9 Nm (0.9 m kg, 6.5 ft • • Ê: kg, 13 ft 18 Nm (1.8 m •...

  • Page 211: Removal

    ENGINE ASSEMBLY REMOVAL 1. Remove: • Rear engine mounting nut • Front engine mounting nuts • Washers NOTE: Do not remove the engine mounting bolts. 2. Remove: • Engine assembly Removal steps: • Screw in the engine mounting bolt spacers (front and rear) using the engine mount spacer wrench 1 so that there is a gap between each engine mounting bolt spacer 2 and engine...
  • Page 212 ENGINE ASSEMBLY • Install the engine mount spacer wrench 1. Engine mount spacer wrench: 90890-01489, YS-01489 • Tighten the rear engine mounting bolt spacer. Rear engine mounting bolt spacer: 7 Nm (0.7 m · kg, 5.1 ft · lb) • Tighten the rear engine mounting nut. Rear engine mounting nut: 65 Nm (6.5 m ·...

  • Page 213: Exhaust Pipe And Muffler

    EXHAUST PIPE AND MUFFLER EXHAUST PIPE AND MUFFLER Order Job name/Part name Q’ty Remarks Exhaust pipe and muffler removal Remove the parts in the order listed below. Slide rail suspension Refer to “SLIDE RAIL SUSPENSION” in CHAPTER 4. Front axle assembly/track Refer to “FRONT AXLE AND TRACK”...

  • Page 214: Installation

    EXHAUST PIPE AND MUFFLER INSTALLATION 1. Install: • Exhaust pipe 1 NOTE: Hang the exhaust pipe to the frame a. 2. Install: • Muffler 1 3. Tighten: • Muffler band bolt 1 • Muffler bolts 2 • Exhaust pipe bolts 3 Muffler band bolt: 20 Nm (2.0 m ·...
  • Page 215 EXHAUST PIPE AND MUFFLER 4. Install: • Muffler cover 1 5. Tighten: • Muffler cover bolts 2 Tightening steps: • Finger tighten the muffler cover bolts. • Tighten the bolts towards the rear of the machine to the specified torque. •...

  • Page 216: Camshafts

    CAMSHAFTS CAMSHAFTS CYLINDER HEAD COVER È: È kg, 7.2 ft 10 Nm (1.0 m • • É: kg, 8.7 ft 12 Nm (1.2 m • • Ê: kg, 9.4 ft 13 Nm (1.3 m • • É Ê Q’ty Remarks Order Job name/Part name Cylinder head cover removal...

  • Page 217: Camshafts

    CAMSHAFTS CAMSHAFTS È: kg, 5.1 ft 7 Nm (0.7 m • • É É: kg, 7.2 ft 10 Nm (1.0 m • • Ê: kg, 17 ft 24 Nm (2.4 m • • Ê Ê É È Q’ty Remarks Order Job name/Part name Camshaft removal Remove the parts in the order listed below.

  • Page 218: Removal

    CAMSHAFTS REMOVAL 1. Remove: • Timing accessing screw • Crankshaft end accessing screw 2. Align: • “I” mark a on the A.C. magneto rotor (with the stationary pointer b on the A.C. magneto cover) NOTE: • Turn the crankshaft clockwise. •...

  • Page 219: Inspection

    CAMSHAFTS 7. Remove: • Intake camshaft sprocket 1 • Exhaust camshaft sprocket 2 (Use the special tool 3) Rotor holding tool: 90890-01235, YU-01235 INSPECTION 1. Inspect: • Camshaft lobes Blue discoloration/pitting/scratches → Replace the camshaft. 2. Measure: • Camshaft lobe dimensions a and b Out of specification →...
  • Page 220 CAMSHAFTS 3. Measure: • Camshaft runout Out of specification → Replace. Camshaft runout: 0.03 mm (0.0012 in) 4. Measure: • Camshaft-journal-to-camshaft-cap clearance Out of specification → Measure the camshaft journal diameter. Camshaft-journal-to-camshaft-cap clearance: 0.028 ~ 0.062 mm (0.0011 ~ 0.0024 in) Measurement steps: •...
  • Page 221 CAMSHAFTS 6. Inspect: • Camshaft sprocket More than 1/4 tooth a wear → Replace the camshaft sprockets and the timing chain as a set. a 1/4 tooth b Correct 1 Timing chain roller 2 Camshaft sprocket 7. Inspect: • Timing chain guide (top side 1) Damage/wear →...

  • Page 222: Installation

    CAMSHAFTS INSTALLATION 1. Install: • Exhaust camshaft sprocket 1 • Intake camshaft sprocket 2 (with the special tool 3) Rotor holding tool: 90890-01235, YU-01235 • Camshaft sprocket bolts Camshaft sprocket bolt: 24 Nm (2.4 m · kg, 17 ft · lb) NOTE: Make sure that the holes a in the cylinder #3 cam and marks b and c on the camshaft sprockets are...
  • Page 223 CAMSHAFTS 3. Install: • Dowel pins • Intake camshaft caps • Exhaust camshaft caps NOTE: • The “I” mark refers to the intake camshaft caps and the “E” mark refers to the exhaust camshaft cap. • Install the camshaft caps with the arrow mark a pointing towards the right side of the engine.
  • Page 224 CAMSHAFTS 5. Install: • Timing chain tensioner Installation steps: • While lightly pressing the timing chain tensioner rod by hand, turn the tensioner rod fully clock- wise with a thin screwdriver 1. NOTE: Make sure that the tensioner rod has been fully set clockwise.
  • Page 225 ® • Apply Sealant (Quick Gasket ) or Yamaha bond No. 1215 2 onto the mating surfaces of the cylin- der head cover gasket and cylinder head. • Tighten the cylinder head cover bolts stages and in a crisscross pattern.

  • Page 226: Cylinder Head

    CYLINDER HEAD CYLINDER HEAD É È È: kg, 8.7 ft 12 Nm (1.2 m • • É: kg, 14 ft 20 Nm (2.0 m • • Q’ty Remarks Order Job name/Part name Cylinder head removal Remove the parts in the order listed below. Engine Refer to “ENGINE ASSEMBLY”.

  • Page 227: Removal

    CYLINDER HEAD REMOVAL 1. Remove: • Cylinder head bolts NOTE: Loosen each bolt 1/2 of a turn at a time. After all of the bolt are fully loosened, remove them. INSPECTION 1. Eliminate: • Combustion chamber carbon deposits (with a rounded scraper) NOTE: Do not use a sharp instrument to avoid damaging or scratching:...

  • Page 228: Installation

    CYLINDER HEAD INSTALLATION 1. Install: • Dowel pins 1 • Gasket 2 2. Install: • Cylinder head NOTE: Pass the timing chain through the timing chain cav- ity. 3. Tighten: • Cylinder head bolts (M10) NOTE: The tightening procedure of the cylinder head bolts is angle controlled, therefore tighten the bolts using the following procedure.
  • Page 229 CYLINDER HEAD • Tighten the cylinder head bolts further to reach the specified angle 180° in the proper tightening sequence as shown. Cylinder head bolt (M10): Final: Specified angle 180° WARNING When the bolts are tightened more than the specified angle, do not loosen the bolt and then retighten it.

  • Page 230: Valves And Valve Springs

    VALVES AND VALVE SPRINGS VALVES AND VALVE SPRINGS Q’ty Remarks Order Job name/Part name Valves and valve springs removal Remove the parts in the order listed below. Cylinder head Refer to “CYLINDER HEAD”. Valve lifter Valve pad Valve cotter Upper spring seat Valve spring Intake valve Exhaust valve...

  • Page 231: Removal

    VALVES AND VALVE SPRINGS REMOVAL The following procedure applies to all of the valves and related components. NOTE: Before removing the internal parts of the cylinder head (e.g., valves, valve springs, valve seats), make sure the valves properly seal. 1. Remove: •...

  • Page 232: Inspection

    VALVES AND VALVE SPRINGS 4. Remove: • Upper spring seat 1 • Valve spring 2 • Valve 3 • Valve stem seal 4 • Lower spring seat 5 NOTE: Identify the position of each part very carefully so that it can be reinstalled in its original place. INSPECTION 1.
  • Page 233 VALVES AND VALVE SPRINGS • After installing the valve guide, bore the valve guide with the valve guide reamer 3 to obtain the proper valve-stem-to-valve-guide clearance. NOTE: After replacing the valve guide, reface the valve seat. Valve guide remover (ø5): 90890-04097, YM-04097 Valve guide installer (ø5): 90890-04098, YM-04098...
  • Page 234 VALVES AND VALVE SPRINGS 9. Measure: • Valve seat width a Out of specification → Replace the cylinder head. 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 235 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 lapping compound. NOTE: For the best lapping results, lightly tap the valve seat while rotating the valve back and forth between your hands.

  • Page 236: Installation

    VALVES AND VALVE SPRINGS 13. Measure: • Valve spring tilt a Out of specification → Replace the valve spring. Maximum valve spring tilt: 2.5°/1.7 mm (0.07 in) 14. Inspect: • Valve lifter Damage/scratches → Replace the valve lift- ers and cylinder head. INSTALLATION 1.
  • Page 237 VALVES AND VALVE SPRINGS 3. Install: • Lower spring seat 1 • Valve stem seal 2 • Valve 3 • Valve spring 4 • Upper spring seat 5 (into the cylinder head) NOTE: • Make sure each valve is installed in its original place.
  • Page 238 VALVES AND VALVE SPRINGS 6. Lubricate: • Valve pad • Valve lifter (with the recommended lubricant) Recommended lubricant: Molybdenum disulfide oil 7. Install: • Valve pad • Valve lifter NOTE: • The valve lifter must move smoothly when rotated with a finger. •...

  • Page 239: A.c. Magneto Rotor And Starter Clutch

    A.C. MAGNETO ROTOR AND STARTER CLUTCH A.C. MAGNETO ROTOR AND STARTER CLUTCH Ê: È: 6 Nm (0.6 m kg, 4.3 ft kg, 8.7 ft 12 Nm (1.2 m • • • • É: Ë: 10 Nm (1.0 m kg, 7.2 ft 130 Nm (13.0 m kg, 94 ft •...

  • Page 240: Removal

    A.C. MAGNETO ROTOR AND STARTER CLUTCH REMOVAL 1. Remove: • A.C. magneto rotor bolt • Washer NOTE: • While holding the A.C. magneto rotor 1 with the sheave holder 2, loosen the magneto rotor bolt. • Do not allow the sheave holder to touch the pro- jection on the A.C.

  • Page 241: Inspection

    A.C. MAGNETO ROTOR AND STARTER CLUTCH 3. Remove: • Starter clutch NOTE: • While holding the magneto rotor with the sheave holder, remove the starter clutch bolts 1. • Do not allow the sheave holder to touch the pro- jection on the magneto rotor. Sheave holder: 90890-01701, YS-01880-A INSPECTION...

  • Page 242: Installation

    A.C. MAGNETO ROTOR AND STARTER CLUTCH 4. Inspect: É • Starter clutch operation Installation steps: • Install the starter clutch gear onto the starter clutch and hold the starter clutch. È • When turning the starter clutch gear clockwise È, the starter clutch and the starter clutch gear should engage, otherwise the starter clutch is faulty and must be replaced.
  • Page 243 • Do not allow the sheave holder to touch the pro- jection on the magneto rotor. Sheave holder: 90890-01701, YS-01880-A 5. Apply: • Sealant (onto the A.C. magneto lead grommet) Yamaha bond No. 1215: 90890-85505 ® Quick gasket ACC-QUICK-GS-KT 5-41...

  • Page 244: Oil Pan And Oil Pump

    OIL PAN AND OIL PUMP OIL PAN AND OIL PUMP È È É Ê È: kg, 7.2 ft 10 Nm (1.0 m • • É: kg, 8.7 ft 12 Nm (1.2 m • • Ê: kg, 11 ft 15 Nm (1.5 m •...
  • Page 245 OIL PAN AND OIL PUMP È: kg, 2.2 ft 3 Nm (0.3 m • • È È È Q’ty Remarks Order Job name/Part name Oil pump disassembly Remove the parts in the order listed below. Oil pan divider Oil pump housing cover 1 Oil pump housing cover 2 Washer Oil pump outer rotor 1...
  • Page 246 OIL PAN AND OIL PUMP È: kg, 2.2 ft 3 Nm (0.3 m • • È È È Q’ty Remarks Order Job name/Part name Check ball seat Check ball Spring Spacer Relief valve cover Spring Relief valve Oil strainer Oil pump housing For assembly, reverse the disassembly pro- cedure.

  • Page 247: Removal

    OIL PAN AND OIL PUMP REMOVAL 1. Remove: • Oil pan 1 NOTE: Loosen each bolt 1/4 of a turn at a time, in stages and in a crisscross pattern. After all of the bolts are fully loosened, remove them. 2.
  • Page 248 OIL PAN AND OIL PUMP 3. Inspect: • Oil pump operation Rough movement → Repeat steps (1) and (2) or replace the defective part(s). NOTE: Install the oil pump gear to check the oil pump oper- ation. 4. Inspect: • Relief valve body 1 •...

  • Page 249: Installation

    OIL PAN AND OIL PUMP INSTALLATION 1. Lubricate: • Inner rotor • Outer rotor • Oil pump shaft (with the recommended lubricant) Recommended lubricant: Engine oil 2. Install: • Pin • Inner rotor • Outer rotor NOTE: • Each set of inner and outer rotors should be installed with both punch marks a facing in the same direction, either away from or towards the oil pump assembly.
  • Page 250 OIL PAN AND OIL PUMP 5. Install: • Oil pump driven gear 1 Oil pump driven gear bolt: 15 Nm (1.5 m · kg, 11 ft · lb) NOTE: • Install the oil pump gear with the stamped mark “4XV” facing towards the oil pump assembly. •...

  • Page 251: Crankcase

    CRANKCASE CRANKCASE CRANKCASE É È: 10 Nm (1.0 m kg, 7.2 ft Ê É • • É: kg, 8.7 ft 12 Nm (1.2 m • • Ê: kg, 17 ft 24 Nm (2.4 m • • É Ë: kg, 18 ft 25 Nm (2.5 m •...
  • Page 252 CRANKCASE É È: kg, 7.2 ft 10 Nm (1.0 m É Ê • • É: kg, 8.7 ft 12 Nm (1.2 m • • Ê: kg, 17 ft 24 Nm (2.4 m • • É Ë: kg, 18 ft 25 Nm (2.5 m •...

  • Page 253: Connecting Rods And Pistons

    CRANKCASE CONNECTING RODS AND PISTONS Order Job name/Part name Q’ty Remarks Connecting rods and pistons removal Remove the parts in the order listed below. Connecting rod cap Big end bearing Piston pin clip Piston pin Piston Connecting rod Top ring 2nd ring Oil ring For installation, reverse the removal proce-...

  • Page 254: Crankshaft And Balancer Shaft

    CRANKCASE CRANKSHAFT AND BALANCER SHAFT È: kg, 7.2 ft 10 Nm (1.0 m • • É: kg, 25 ft 35 Nm (3.5 m • • É 18 19 15 14 10 11 È É Order Job name/Part name Q’ty Remarks Crankshaft and balancer shaft removal Remove the parts in the order listed below.
  • Page 255 CRANKCASE È: kg, 7.2 ft 10 Nm (1.0 m • • É: kg, 25 ft 35 Nm (3.5 m • • É 18 19 15 14 10 11 È É Q’ty Remarks Order Job name/Part name Spring Bearing retainer Bearing Bearing/circlip For installation, reverse the removal proce- dure.

  • Page 256: Removal

    CRANKCASE REMOVAL 1. Remove: • Crankcase bolts NOTE: • Place the engine upside down. • Loosen the bolts in decreasing numerical order of the embossed numbers on the crankcase. • Loosen each bolt 1/4 of a turn at a time. After all of the bolts are fully loosened, remove them.
  • Page 257 CRANKCASE 5. Remove: • Piston pin clips 1 • Piston pin 2 • Piston 3 • Connecting rod 4 CAUTION: Do not use a hammer to drive the piston pin out. NOTE: • For reference during installation, put identification marks on the piston crown. •...

  • Page 258: Inspection

    CRANKCASE 8. Straighten the lock washer tab. 9. Loosen: • Balance weight bolts 1 NOTE: Place a piece of wood a between the balancer 2 and crankcase. 10. Remove: • Balancer weight 1 • Balancer weight 2 • Water pump drive gear •...
  • Page 259 CRANKCASE “C” = maximum of D “T” = maximum of D or D – maximum of D or D “R” = maximum of D or D – maximum of or D • If out of specification, replace the cylinder, and the piston and piston rings as a set.
  • Page 260 CRANKCASE Piston rings side clearance: Top ring: 0.030 ~ 0.070 mm (0.0012 ~ 0.0028 in) 2nd ring: 0.020 ~ 0.060 mm (0.0008 ~ 0.0024 in) 4. Install: • Piston ring (into the cylinder) NOTE: Level the piston ring in the cylinder with the piston crown.
  • Page 261 CRANKCASE 8. Measure: • Piston pin bore inside diameter Out of specification → Replace the piston. Piston pin bore inside diameter: 19.004 ~ 19.015 mm (0.7482 ~ 0.7486 in) 9. Calculate: • Piston pin to piston pin bore clearance Out of specification → Replace the piston pin and piston as a set.
  • Page 262 CRANKCASE 11. Inspect: • Crankshaft journal surfaces • Crankshaft pin surfaces • Bearing surfaces Scratches/wear → Replace the crankshaft. 12. Measure: • Crankshaft-journal-to-crankshaft-journal- bearing clearance Out of specification → Replace the crankshaft journal bearings. Crankshaft-journal-to-crankshaft- journal-bearing clearance: 0.027 ~ 0.045 mm (0.0011 ~ 0.0018 in) Measurement steps: CAUTION:...
  • Page 263 CRANKCASE • Install the crankshaft journal lower bearings 1 into the lower crankcase and assemble the crankcase halves. NOTE: • Align the projections a of the crankshaft journal lower bearings with the notches b in the crank- case. • Do not move the crankshaft until the clearance measurement has been completed.
  • Page 264 CRANKCASE 13. Select: • Crankshaft journal bearings (J1 ~ J4) NOTE: • The numbers È stamped into the crankshaft web and the numbers É stamped into the lower crankcase are used to determine the replace- ment crankshaft journal bearing sizes. •...
  • Page 265 CRANKCASE Measurement steps: CAUTION: Do not interchange the big end bearings and connecting rods. To obtain the correct crank- shaft-pin-to-big-end-bearing clearance and pre- vent engine damage, the big end bearings must be installed in their original positions. • Clean the big end bearings, crankshaft pins, and bearing portions of the connecting rods.
  • Page 266 CRANKCASE • Tighten the connecting rod nuts. Connecting rod nut: 1st: 20 Nm (2.0 m · kg, 14 ft · lb) Final: Specified angle 120° • Replace the connecting rod bolts and nuts with new ones. CAUTION: Tighten the connecting rod bolts using the plastic-region tightening angle method.
  • Page 267 CRANKCASE 15. Select: • Big end bearings (P1 ~ P3) NOTE: • The numbers È stamped into the crankshaft web and the numbers 1 on the connecting rods are used to determine the replacement big end bear- ing sizes. • “P1” ~ “P3” refer to the bearings shown in the crankshaft illustration.
  • Page 268 CRANKCASE 19. Inspect: • Balancer drive gear • Balancer driven gear 1 Damage/wear → Replace the crankshaft assembly and balancer driven gear as a set. Excessive noise during operation → Replace the crankshaft assembly and balancer driven gear as a set. 20.

  • Page 269: Installation

    CRANKCASE INSTALLATION 1. Install: • Balancer driven gear 1 • Boss 2 NOTE: Align the punch mark a on the boss with the punch mark b on the balancer driven gear. 2. Install: • Balancer driven gear assembly 1 • Balancer shaft 2 NOTE: Align the projection a on the balancer shaft with the slot b in the balancer driven gear.
  • Page 270 CRANKCASE 5. Tighten: • Balancer weight bolts 1 NOTE: Place a wood a between the balancer 2 and crankcase. Balancer weight bolt: 35 Nm (3.5 m · kg, 25 ft · lb) 6. Bend the lock washer tab. 7. Install: •...
  • Page 271 CRANKCASE 10. Lubricate: • Crankshaft pins • Connecting rod inner surface (with the recommended lubricant) Recommended lubricant: Engine oil 11. Install: • Top ring 1 • 2nd ring 2 • Upper oil ring rail 3 • Oil ring expander 4 •...
  • Page 272 CRANKCASE 14. Lubricate: • Piston • Piston rings • Cylinder Recommended lubricant: Engine oil 15. Lubricate: • Bolt threads • Nut seats (with the recommended lubricant) Recommended lubricant: Molybdenum disulfide grease 16. Lubricate: • Crankshaft pins • Big end bearings •...
  • Page 273 CRANKCASE 18. Align: • Bolt heads (with the connecting rod caps) 19. Tighten: • Connecting rod nuts Connecting rod nut: 1st: 20 Nm (2.0 m · kg, 14 ft · lb) Final: Specified angle 120° • Replace the connecting rod bolts and nuts with new ones.
  • Page 274 CRANKCASE 21. Apply: • Sealant (onto the crankcase mating surfaces) Yamaha bond No. 1215: 90890-85505 ® Quick gasket ACC-QUICK-GS-KT NOTE: Do not allow any sealant to come into contact with the oil gallery or crankshaft journal bearings. Do not apply sealant to within 2 ~ 3 mm (0.08 ~ 0.12 in) of the crankshaft journal bearings.
  • Page 275 CRANKCASE 25. Install: • Crankcase bolts NOTE: • Lubricate the bolt threads with engine oil. • Tighten the bolts in the order of the embossed numbers on the crankcase. Crankcase bolt: Bolt 1: 1st: 15 Nm (1.5 m · kg, 11 ft · lb) 2nd: 15 Nm (1.5 m ·...

  • Page 276: Heat Exchanger

    COOL HEAT EXCHANGER COOLING SYSTEM HEAT EXCHANGER È: 10 Nm (1.0 m kg, 7.2 ft • • È RS90M Q’ty Remarks Order Job name/Part name Heat exchanger removal Remove the parts in the order listed below. Coolant Drain. Refer to “COOLING SYSTEM” in CHAPTER Engine assembly Refer to “ENGINE ASSEMBLY”...
  • Page 277 COOL HEAT EXCHANGER È: kg, 7.2 ft 10 Nm (1.0 m • • È RS90M Q’ty Remarks Order Job name/Part name Carburetor heating outlet hose Water pump assembly Coolant hose 6 Oil cooler inlet hose Oil cooler Oil cooler outlet hose Thermostat assembly Coolant hose 7 Coolant hose 8...
  • Page 278 COOL HEAT EXCHANGER È: kg, 7.2 ft 10 Nm (1.0 m • • È RS90M Q’ty Remarks Order Job name/Part name Carburetor heating inlet hose 1 For RS90M Carburetor coolant shut-off assembly For RS90M Carburetor heating inlet hose 2 For RS90M For installation, reverse the removal proce- dure.

  • Page 279: Inspection

    COOL HEAT EXCHANGER INSPECTION 1. Inspect: • Coolant hoses • Heat exchangers • Oil cooler • Coolant pipes • Carburetor coolant shut-off assembly (For RS90M) Cracks/damage → Replace. RS90M 2. Measure: • Filler cap opening pressure Cap opens with a pressure below the speci- fied pressure →...

  • Page 280: Installation

    COOL HEAT EXCHANGER INSTALLATION 1. Install: • Heat exchangers Use the rivet gun. 2. Install: • O-ring • Oil cooler 1 Oil cooler bolt: 10 Nm (1.0 m · kg, 7.2 ft · lb) ® LOCTITE NOTE: Install the oil cooler with the manufacturer’s mark a facing down.

  • Page 281: Thermostat

    COOL THERMOSTAT THERMOSTAT Order Job name/Part name Q’ty Remarks Thermostat disassembly Remove the parts in the order listed below. Coolant temperature sensor coupler Disconnect. Coolant temperature sensor Coolant hose 9 Disconnect. Coolant hose 10 Disconnect. Oil cooler outlet hose Disconnect. Coolant hose 8 Disconnect.

  • Page 282: Inspection

    COOL THERMOSTAT INSPECTION 1. Inspect: • Thermostat Does not open at 69 ~ 73 °C (156 ~ 163 °F) → Replace. Inspection steps: • Suspend the thermostat in a container filled with water. • Slowly heat the water. Place a thermometer in the water. •...
  • Page 283 COOL THERMOSTAT 3. Install: • Coolant temperature sensor (to the thermostat housing) Coolant temperature sensor: 23 Nm (2.3 m · kg, 17 ft · lb) CAUTION: Use extreme care when handling the coolant temperature sensor. Replace any part that was dropped or subjected to a strong impact.

  • Page 284: Water Pump

    COOL WATER PUMP WATER PUMP È: kg, 8.7 ft 12 Nm (1.2 m • • È Order Job name/Part name Q’ty Remarks Water pump removal Remove the parts in the order listed below. Frame cross member Refer to “ENGINE ASSEMBLY” in CHAPTER Coolant hose 6 Disconnect.
  • Page 285 COOL WATER PUMP Q’ty Remarks Order Job name/Part name Water pump disassembly Remove the parts in the order listed below. Water pump housing cover Gasket Circlip Impeller shaft gear Impeller shaft assembly Water pump seal Oil seal Bearing Water pump housing For assembly, reverse the disassembly pro- cedure.

  • Page 286: Removal

    COOL WATER PUMP REMOVAL 1. Remove: • Timing mark accessing screw • Crankshaft end accessing screw 2. Align: • “I” mark a on the A.C. magneto rotor (with the stationary pointer b on the A.C. magneto cover) NOTE: Turn the crankshaft clockwise. 3.

  • Page 287: Inspection

    COOL WATER PUMP INSPECTION 1. Inspect: • Water pump housing cover 1 • Water pump housing 2 • Impeller 3 • Impeller shaft gear 4 • Rubber damper 5 • Rubber damper holder 6 • Water pump seal • Oil seal Cracks/damage/wear →...

  • Page 288: Installation

    • Install the water pump seal 1 with the mechani- cal seal installer 4 and 40 and 50 mm bearing driver 5. • Before installing the water pump seal, apply Yamaha bond No.1215 2 or Quick gasket ® the water pump housing 3. Mechanical seal installer:...

  • Page 289: Chapter 7. Carburetion

    CARB CARBURETORS AND FUEL PUMP CARBURETION CARBURETORS AND FUEL PUMP RS10MK È: kg, 7.2 ft 10 Nm (1.0 m • • È È È È Q’ty Remarks Order Job name/Part name Carburetor removal Remove the parts in the order listed below. Right side cover Refer to “BRAKE”...
  • Page 290 CARB CARBURETORS AND FUEL PUMP RS10MK È: kg, 7.2 ft 10 Nm (1.0 m • • È È È È Q’ty Remarks Order Job name/Part name Carburetor assembly Carburetor joint Carburetor heating inlet hose 1 Disconnect. For RS90M Carburetor coolant shut-off assembly For RS90M Fuel hose Disconnect.
  • Page 291 CARB CARBURETORS AND FUEL PUMP Order Job name/Part name Q’ty Remarks Carburetor separation Remove the parts in the order listed below. Sub-wire harness 3 Carburetor heating hose Fuel delivery hose Float chamber air vent hose Vacuum hose Spring Starter plunger link Connecting bolt Throttle position sensor Carburetor...
  • Page 292 CARB CARBURETORS AND FUEL PUMP Order Job name/Part name Q’ty Remarks Carburetor disassembly Remove the parts in the order listed below. NOTE: The following procedure applies to all of the carburetors. Throttle stop screw Throttle cable holder Starter plunger Vacuum chamber cover Piston valve spring Piston valve Jet needle holder...
  • Page 293 CARB CARBURETORS AND FUEL PUMP Order Job name/Part name Q’ty Remarks Fuel drain bolt Float chamber Float pin Float Needle valve Main jet Needle jet holder Needle jet Pilot jet For assembly, reverse the disassembly pro- cedure.

  • Page 294: Inspection

    CARB CARBURETORS AND FUEL PUMP INSPECTION 1. Inspect: • Carburetor body • Float chamber Cracks/damage → Replace. 2. Inspect: • Fuel passages Obstruction → Clean. NOTE: • Use a petroleum based solvent for cleaning. • Blow out all passage and jets with compressed air.
  • Page 295 CARB CARBURETORS AND FUEL PUMP 7. Inspect: • Piston valve 1 Damage/scratches/wear → Replace. • Rubber diaphragm 2 Cracks/tears → Replace. 8. Inspect: • Vacuum chamber cover 1 • Piston valve spring 2 • Jet needle holder 3 Cracks/damage → Replace. 9.

  • Page 296: Assembly

    CARB CARBURETORS AND FUEL PUMP ASSEMBLY NOTE: • Before assembling the carburetors, wash all of the parts in a petroleum based solvent. • Always use a new gasket and O-rings. 1. Install: • Needle jet • Pilot jet • Main jet •...

  • Page 297: Installation

    CARB CARBURETORS AND FUEL PUMP • If both are fine, adjust the float height by bend- ing the float arm tang 1 on the float. • Recheck the float height. INSTALLATION NOTE: After installing all parts, refer to “CABLE ROUT- ING”...

  • Page 298: Fuel Level Adjustment

    CARB CARBURETORS AND FUEL PUMP FUEL LEVEL ADJUSTMENT 1. Measure: • Fuel level a Out of specification → Adjust. Fuel level (below the line on the float chamber): 0.2 ~ 2.2 mm (0.008 ~ 0.087 in) Measurement steps: • Install the fuel level gauge 1 to the fuel drain pipe 2.

  • Page 299: Throttle Position Sensor (T

    CARB CARBURETORS AND FUEL PUMP THROTTLE POSITION SENSOR (T.P.S.) INSPECTION AND ADJUSTMENT NOTE: Before adjusting the throttle position sensor, prop- erly adjust the idle speed. 1. Inspect: • Throttle position sensor Inspection steps: • Disconnect the throttle position sensor coupler. •...

  • Page 300: Inspection

    CARB CARBURETORS AND FUEL PUMP 2. Adjust: • Throttle position sensor angle Adjustment steps: • Disconnect the throttle position sensor coupler. • Connect the test coupler to the throttle position sensor. • Connect three dry cells (1.5 V × 3 pcs.) in series to the test coupler.

  • Page 301: Installation

    CARB CARBURETORS AND FUEL PUMP 2. Remove: • Air filter case Refer to “BATTERY INSPECTION” in CHAP- TER 2. 3. Inspect: • Fuel pump operation Inspection steps: The following procedure applies to both of the fuel pump. • Connect the Mity vac 1 to the vacuum hose 2. Mity vac: 90890-06756, YS-42423 •...

  • Page 302: Chapter 8. Electrical

    – ELEC SWITCH INSPECTION ELECTRICAL SWITCH INSPECTION SWITCH INSPECTION Use a pocket tester to check the terminals for conti- nuity. If the continuity is faulty at any point, replace the switch. Pocket tester: 90890-03112, YU-03112-C NOTE: • Set the pocket tester to “0” before starting a test. •...

  • Page 303: Ignition System

    – ELEC IGNITION SYSTEM...

  • Page 304: Circuit Diagram

    – ELEC IGNITION SYSTEM IGNITION SYSTEM CIRCUIT DIAGRAM 1 Pickup coil 4 Main switch 6 Main fuse 9 Battery 0 Engine stop switch A Throttle switch G Ignitor unit H Ignition coil I Spark plug J Throttle position sensor e Ignition fuse...

  • Page 305: Troubleshooting

    – ELEC IGNITION SYSTEM TROUBLESHOOTING NO SPARK OR WEAK SPARK. Check the main fuse and ignition fuse. Refer to “FUSE INSPECTION” in CHAPTER 2. FAULTY Replace the main fuse and/or ignition fuse. Check the battery. Refer to “BATTERY INSPECTION” in CHAPTER 2. OUT OF SPECIFICATION Replace and/or charge the battery.
  • Page 306 – ELEC IGNITION SYSTEM T.O.R.S. OPERATES. Is self-diagnosis code 15, 16, or 42 displayed? Check the affected item(s). Has carburetor icing occurred or is foreign material stuck in the carburetor? Perform carburetor maintenance. Is the throttle switch malfunctioning? Repair or replace the throttle switch. Is the throttle cable free play out of specification? Adjust the throttle cable free play.

  • Page 307: Ignition Spark Gap

    – ELEC IGNITION SYSTEM IGNITION SPARK GAP È 1. Remove: • Ignition coil 2. Measure: • Ignition spark gap Out of specification → Replace the ignition coil. Measurement steps: • Disconnect the ignition coil 1 from the spark plug. É •...

  • Page 308: Pickup Coil

    – ELEC IGNITION SYSTEM PICKUP COIL 1. Disconnect: • Pickup coil coupler 1 2. Connect: • Pocket tester (to the pickup coil coupler) 3. Measure: • Pickup coil resistance Out of specification → Replace. Pickup coil resistance: 189 ~ 231 Ω at 20 °C (68 °F) (Gray –...

  • Page 309: Throttle Override System (T.o.r.s.)

    – ELEC IGNITION SYSTEM THROTTLE OVERRIDE SYSTEM (T.O.R.S.) È If the carburetor or throttle cable should malfunction during operation, T.O.R.S. will operate when the throttle lever is released. T.O.R.S. is designed to interrupt the ignition and keep the engine revolutions between 2,800 and 3,000 r/min if the carburetor fails to return to idle when the lever is released.

  • Page 310: Throttle Switch

    – ELEC IGNITION SYSTEM 3. Check: • Engine stop switch continuity Faulty → Replace the right handlebar switch. Ω × 1 Switch position Continuity – RUN (pulled out) OFF (pushed in) Br Br/W THROTTLE SWITCH 1. Disconnect: • Throttle switch couplers 2.

  • Page 311: Electrical Starting System

    – ELEC ELECTRICAL STARTING SYSTEM 8-10...
  • Page 312 – ELEC ELECTRICAL STARTING SYSTEM TROUBLESHOOTING STARTER MOTOR DOES NOT OPERATE. 1. Connect: • Starter relay terminals (battery side and starter motor side) Check the battery and connectors. Refer to “BATTERY INSPECTION” in CHAPTER Charge and/or replace the battery. Refer to “BATTERY INSPECTION” in CHAPTER 2.

  • Page 313: Circuit Diagram

    – ELEC ELECTRICAL STARTING SYSTEM FAULTY Check the main fuse and ignition fuse. Refer to “FUSE INSPECTION” in CHAPTER 2. Replace the main fuse and/or ignition fuse. FAULTY Check the engine stop switch and main switch. Refer to “IGNITION SYSTEM”. Replace the right handlebar switch and/or main switch.

  • Page 314: Starter Motor

    – ELEC ELECTRICAL STARTING SYSTEM STARTER MOTOR Order Job name/Part name Q’ty Remarks Starter motor removal Remove the parts in the order listed below. Engine assembly Refer to “ENGINE ASSEMBLY” in CHAPTER Starter motor lead Disconnect. Starter motor assembly For installation, reverse the removal proce- dure.
  • Page 315 – ELEC ELECTRICAL STARTING SYSTEM Q’ty Remarks Order Job name/Part name Brush 3 Brush holder Bearing Armature assembly Starter motor yoke For assembly, reverse the disassembly pro- cedure. 8-14...
  • Page 316 – ELEC ELECTRICAL STARTING SYSTEM Inspection 1. Inspect: • Commutator (outer surface) Dirty → Clean with #600 grit sandpaper 1. Hold the armature in a vise 2 and copper or aluminium plate 3. CAUTION: Lightly grip the armature with a vise. 2.
  • Page 317 – ELEC ELECTRICAL STARTING SYSTEM 5. Measure: • Brush length a Out of specification → Replace the starter motor. Brush length wear limit: 5.0 mm (0.20 in) 6. Measure: • Brush spring pressure Fatigue/out of specification → Replace as a set.
  • Page 318 – ELEC ELECTRICAL STARTING SYSTEM 3. Install: • O-ring • Rear bracket 1 NOTE: Align the projection a on the rear bracket 1 with the slot b in the starter motor yoke 2. 4. Install: • Starter motor yoke • O-ring •...

  • Page 319: Charging System

    – ELEC CHARGING SYSTEM 8-18...

  • Page 320: Circuit Diagram

    – ELEC CHARGING SYSTEM TROUBLESHOOTING BATTERY IS NOT CHARGED. 1. Connect: • Pocket tester (to the battery terminals) 2. Measure: OUT OF SPECIFICATION • Battery voltage Battery voltage: more than 12 V at 20 °C (68 °F) • Check the battery. •...

  • Page 321: Battery

    – ELEC CHARGING SYSTEM BATTERY Inspection 1. Inspect: • Battery condition Refer to “BATTERY INSPECTION” in CHAP- TER 2. Battery Storage The battery should be stored if the machine is not going to be used for a long period. 1. Remove: •...

  • Page 322: Lighting System

    – ELEC LIGHTING SYSTEM 8-22...

  • Page 323: Circuit Diagram

    – ELEC LIGHTING SYSTEM LIGHTING SYSTEM CIRCUIT DIAGRAM 2 A.C. magneto 3 Rectifier/regulator 4 Main switch 5 Load control relay 6 Main fuse 9 Battery G Ignitor unit N Frame ground U Tail/brake light ] Meter light _ High beam indicator light b Headlight fuse c Signal fuse e Ignition fuse...

  • Page 324: Troubleshooting

    – ELEC LIGHTING SYSTEM TROUBLESHOOTING HEADLIGHT AND/OR METER LIGHT DO NOT COME ON. Check the headlight and meter light bulb(s). NO CONTINUITY Replace the bulb(s). Check the main fuse, ignition fuse, and headlight fuse. Refer to “FUSE INSPECTION” in CHAPTER 2. FAULTY Replace the main fuse, ignition fuse, and/or head- light fuse.
  • Page 325 – ELEC LIGHTING SYSTEM TAIL LIGHT DOES NOT COME ON. Check the tail/brake light bulb(s). NO CONTINUITY Replace the tail/brake light bulb(s). Check the main fuse, ignition fuse, and signal fuse. Refer to “FUSE INSPECTION” in CHAPTER 2. FAULTY Replace the main fuse, ignition fuse, and/or signal fuse.

  • Page 326: Bulb(S)

    – ELEC LIGHTING SYSTEM BULB(S) 1. Remove: • Headlight bulb a • Tail/brake light bulb b • Meter light bulb c 2. Connect: • Pocket tester (to the bulb terminals) WARNING Keep flammable products and your hands away from the bulb while it is on; it will be hot. Do not touch the bulb until it cools down.

  • Page 327: Load Control Relay

    – ELEC LIGHTING SYSTEM Inspection steps: • Disconnect the headlight relay from the coupler. • Connect the pocket tester (Ω × 1) to the head- light relay terminals as shown. Positive tester probe → Blue/White 1 Negative tester probe → Yellow 2 •...

  • Page 328: Signal System

    – ELEC SIGNAL SYSTEM 8-28...

  • Page 329: Circuit Diagram

    – ELEC SIGNAL SYSTEM SIGNAL SYSTEM CIRCUIT DIAGRAM 2 A.C. magneto 3 Rectifier/regulator 4 Main switch 5 Load control relay 6 Main fuse 9 Battery G Ignitor unit K Coolant temperature sensor N Frame ground R DC back buzzer S Gear position switch T Brake light switch U Tail/brake light V Speed sensor...

  • Page 330: Troubleshooting

    – ELEC SIGNAL SYSTEM TROUBLESHOOTING BRAKE LIGHT DOES NOT COME ON. Check the tail/brake light bulb(s). Refer to “LIGHTING SYSTEM”. NO CONTINUITY Replace the bulb(s). Check the main fuse, ignition fuse, and signal fuse. Refer to “FUSE INSPECTION” in CHAPTER 2. FAULTY Replace the main fuse, ignition fuse, and/or signal fuse.
  • Page 331 – ELEC SIGNAL SYSTEM LOW COOLANT TEMPERATURE INDICATOR LIGHT, COOLANT TEMPERATURE WARNING INDICATOR AND/OR WARNING LIGHT DO NOT COME ON. Check the low coolant temperature indicator light bulb and warning light bulb. Refer to “LIGHTING SYSTEM”. NO CONTINUITY Replace the low coolant temperature indicator light bulb and/or warning light bulb.
  • Page 332 – ELEC SIGNAL SYSTEM FUEL METER AND/OR FUEL LEVEL WARNING INDICATOR AND/OR WARNING LIGHT DOES NOT OPERATE. Check the warning light bulb. Refer to “LIGHTING SYSTEM”. NO CONTINUITY Replace the bulb. Check the main fuse, ignition fuse, and signal fuse. Refer to “FUSE INSPECTION”...
  • Page 333 – ELEC SIGNAL SYSTEM OIL LEVEL WARNING INDICATOR AND/OR WARNING LIGHT DO NOT COME ON. Check the warning light bulb. Refer to “LIGHTING SYSTEM”. Replace the bulb. NO CONTINUITY Check the main fuse, ignition fuse, and signal fuse. Refer to “FUSE INSPECTION” in CHAPTER 2. FAULTY Replace the main fuse, ignition fuse, and/or signal fuse.
  • Page 334 – ELEC SIGNAL SYSTEM SPEEDOMETER DOES NOT OPERATE. Check the main fuse, ignition fuse, and signal fuse. Refer to “FUSE INSPECTION” in CHAPTER 2. Replace the main fuse, ignition fuse, and/or signal FAULTY fuse. Check the battery. Refer to “BATTERY INSPECTION” in CHAPTER 2. OUT OF SPECIFICATION Replace and/or charge the battery.
  • Page 335 – ELEC SIGNAL SYSTEM BACK BUZZER DOES NOT SOUND. (RS90R/RSG90/RST90/RST90TF) Check the main fuse, ignition fuse, and signal fuse. Refer to “FUSE INSPECTION” in CHAPTER 2. Replace the main fuse, ignition fuse, and/or signal FAULTY fuse. Check the battery. Refer to “BATTERY INSPECTION” in CHAPTER 2. OUT OF SPECIFICATION Replace and/or charge the battery.

  • Page 336: Brake Light Switch

    – ELEC SIGNAL SYSTEM BRAKE LIGHT SWITCH 1. Disconnect: • Brake light switch coupler 2. Connect: • Pocket tester (to the brake light switch coupler) 3. Check: • Brake light switch continuity Faulty → Replace. Switch position Continuity Brake lever operates Brake lever does not operate GEAR POSITION SWITCH (RS90R/RSG90/...

  • Page 337: Coolant Temperature Sensor

    – ELEC SIGNAL SYSTEM 2. Connect: • Battery 3. Check: • DC back buzzer Does not sound → Replace. COOLANT TEMPERATURE SENSOR 1. Disconnect the coolant temperature sensor coupler 1 and remove the coolant temperature sensor. CAUTION: Handle the coolant temperature sensor with special care.

  • Page 338: Oil Level Switch

    – ELEC SIGNAL SYSTEM 5. Install the coolant temperature sensor and con- nect the coolant temperature sensor coupler. Coolant temperature sensor: 23 Nm (2.3 m · kg, 17 ft · lb) CAUTION: Do not overtighten the coolant temperature sensor. OIL LEVEL SWITCH 1.

  • Page 339: Speed Sensor

    – ELEC SIGNAL SYSTEM 3. Measure: • Fuel sender resistance (full a) • Fuel sender resistance (empty b) Ω × 1 Out of specification → Replace. – Fuel sender resistance (full): 10 ~ 12 Ω at 20 °C (68 °F) Fuel sender resistance (empty): 179 ~ 185 Ω...

  • Page 340: Grip Warmer System

    – ELEC GRIP WARMER SYSTEM 8-40...

  • Page 341: Circuit Diagram

    – ELEC GRIP WARMER SYSTEM GRIP WARMER SYSTEM CIRCUIT DIAGRAM 2 A.C. magneto 3 Rectifier/regulator 4 Main switch 5 Load control relay 6 Main fuse 9 Battery E Grip warmer F Thumb warmer G Ignitor unit L Grip warmer adjustment switch M Thumb warmer adjustment switch N Frame ground O Passenger grip warmer relay...

  • Page 342: Troubleshooting

    – ELEC GRIP WARMER SYSTEM TROUBLESHOOTING GRIP WARMER AND THUMB WARMER DO NOT OPERATE. Check the main fuse, ignition fuse, and signal fuse. Refer to “FUSE INSPECTION” in CHAPTER 2. FAULTY Replace the main fuse, ignition fuse, and/or signal fuse. Check the battery.
  • Page 343 – ELEC GRIP WARMER SYSTEM PASSENGER GRIP WARMER DOES NOT OPERATE. (RST90/RST90TF) Check the main fuse, ignition fuse, and signal fuse. Refer to “FUSE INSPECTION” in CHAPTER 2. Replace the main fuse, ignition fuse, and/or signal FAULTY fuse. Check the battery. Refer to “BATTERY INSPECTION”...

  • Page 344: Grip And Thumb Warmer Coil

    – ELEC GRIP WARMER SYSTEM GRIP AND THUMB WARMER COIL 1. Disconnect: • Grip warmer leads • Thumb warmer coupler 2. Connect: • Pocket tester (to the grip warmer coil leads and/or thumb warmer coupler) 3. Measure: • Grip warmer resistance 1 •...

  • Page 345: Grip Warmer Adjustment Switch

    – ELEC GRIP WARMER SYSTEM GRIP WARMER ADJUSTMENT SWITCH 1. Disconnect: • Grip warmer adjustment switch coupler 2. Connect: • Pocket tester (to the grip warmer adjustment switch cou- pler) 3. Check: • Grip warmer adjustment switch continuity Faulty → Replace the left handlebar switch. Color code Switch position...

  • Page 346: Passenger Grip Warmer Switch (Rst90/Rst90Tf)

    – ELEC GRIP WARMER SYSTEM PASSENGER GRIP WARMER SWITCH (RST90/RST90TF) 1. Disconnect: • Passenger grip warmer switch coupler 1 2. Connect: • Pocket tester (to the passenger grip warmer switch coupler) 3. Check: • Passenger grip warmer switch continuity Faulty → Replace. Ω...

  • Page 347: Carburetor Heater System

    – ELEC CARBURETOR HEATER SYSTEM 8-48...

  • Page 348: Circuit Diagram

    – ELEC CARBURETOR HEATER SYSTEM CARBURETOR HEATER SYSTEM CIRCUIT DIAGRAM 2 A.C. magneto 3 Rectifier/regulator 4 Main switch 5 Load control relay 6 Main fuse 9 Battery B Carburetor heater relay C Carburetor ground D Carburetor heater G Ignitor unit K Coolant temperature sensor N Frame ground c Signal fuse...

  • Page 349: Troubleshooting

    – ELEC CARBURETOR HEATER SYSTEM TROUBLESHOOTING CARBURETOR HEATER DO NOT OPERATE. Check the main fuse, signal fuse, carburetor heater fuse and ignition fuse. Refer to “FUSE INSPECTION” in CHAPTER 2. FAULTY Replace the main fuse, signal fuse, carburetor heater fuse and/or ignition fuse. Check the battery.

  • Page 350: Carburetor Heater Relay

    – ELEC CARBURETOR HEATER SYSTEM CARBURETOR HEATER RELAY 1. Inspect: • Carburetor heater relay 1 Inspection steps: • Disconnect the carburetor heater relay from the coupler. • Connect the pocket tester (Ω × 1) and battery (12 V) to the carburetor heater relay terminals as shown.

  • Page 351: Self-Diagnosis

    – ELEC SELF-DIAGNOSIS SELF-DIAGNOSIS 4 2 1 This model features a self-diagnosing system for following displays. 1 Fuel meter 2 Fuel level warning indicator 3 Self-diagnosis warning indicator 4 Warning light 5 DIAG code (odometer/tripmeter) NOTE: The oil level warning indicator 6 and the warning light 4 come on when the engine oil level is low.

  • Page 352: Self-Diagnosis Code

    – ELEC SELF-DIAGNOSIS SELF-DIAGNOSIS CODE DIAG Item Condition Displayed code Fuel sender Disconnected Short-circuit 0.5s Repeat 0.5s — The warning light, fuel meter, and fuel level warning indicator flash. T.P.S. Disconnected Short-circuit T.P.S. Locked 0.5s 0.5s Coolant tempera- Disconnected ture sensor Short-circuit Grip warmer adjust- Short-circuit...
  • Page 353 – ELEC SELF-DIAGNOSIS DIAG Item Condition Displayed code No signal are • Open or short circuit in received from wire. (Yellow/Black) Er_1 igniter • Malfunction in meter. • Malfunction in ignitor unit. No signal are • Improper connection in received from the headlight sub-wire har- The self-diagnosis code flashes in the igniter within the...

  • Page 354: Chapter 9. Specifications

    SPEC GENERAL SPECIFICATIONS SPECIFICATIONS GENERAL SPECIFICATIONS Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Model code number: 8ES1 (RS90 “USA/Canada”) 8FJ1 (RS90R “USA/Canada”) 8FJ2 (RS90R “Europe”) 8FL1 (RSG90 “USA/Canada”) 8FL2 (RSG90 “Europe”) 8FK1 (RS90M “USA/Canada”) 8FK2 (RS90M “Europe”) 8ET1 (RST90 “USA/Canada”) 8ET2 (RST90 “Europe”) 8FM1 (RST90TF “Europe”) 8FM2 (RST90TF “Canada”) Dimensions: Overall length...
  • Page 355 SPEC GENERAL SPECIFICATIONS Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Engine: Engine type Liquid-cooled, 4-stroke, DOHC Cylinder type Backward-inclined parallel 3-cylinder Displacement 973 cm (59.37 cu.in) Bore × stroke 79.0 × 66.2 mm (3.11 × 2.61 in) Compression ratio 11.3 : 1 Maximum hose power r/min 84.7 kw (115.2 PS)/8,500 r/min Maximum torque r/min 101.6 Nm (10.4 kgf)/7,000 r/min...
  • Page 356 SPEC GENERAL SPECIFICATIONS Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Transmission: Primary reduction system V-Belt Primary reduction ratio 3.8 ~ 1 : 1 Clutch type Automatic centrifugal engagement Secondary reduction system Chain Secondary reduction ratio 1.73 (38/22) (RS90/RS90R) 1.77 (39/22) (RSG90/RST90 “USA/Canada”) 2.00 (40/20) (RS90M) 1.95 (39/20) (RST90 “Europe”/RST90TF) Reverse system No (RS90/RS90M)

  • Page 357: Maintenance Specifications

    SPEC MAINTENANCE SPECIFICATIONS MAINTENANCE SPECIFICATIONS ENGINE Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Cylinder head: Volume (with spark plug) 22.82 ~ 23.62 cm (1.39 ~ 1.44 cu.in) <Warpage limit> 0.10 mm (0.0039 in) Lines indicate straight edge measurement. Cylinder: Material Aluminum alloy with dispersion coating Bore size 79.000 ~ 79.010 mm (3.1102 ~ 3.1106 in) <Taper limit>...
  • Page 358 SPEC MAINTENANCE SPECIFICATIONS Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Valves, valve seats, valve guides: Valve clearance (cold) Intake 0.15 ~ 0.22 mm (0.0059 ~ 0.0087 in) Exhaust 0.21 ~ 0.25 mm (0.0083 ~ 0.0098 in) Valve dimensions Valve head diameter A Intake 29.9 ~ 30.1 mm (1.1771 ~ 1.1850 in) Exhaust 25.9 ~ 26.1 mm (1.0197 ~ 1.0276 in) Valve face width B...
  • Page 359 SPEC MAINTENANCE SPECIFICATIONS Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Valve spring: Free length Intake 39.73 mm (1.56 in) <Limit> 37.7 mm (1.48 in) Exhaust 39.73 mm (1.56 in) <Limit> 37.7 mm (1.48 in) Installed length (valve closed) Intake 33.0 mm (1.30 in) Exhaust 33.0 mm (1.30 in) Compressed spring force (installed) Intake 136 ~ 158 N (13.9 ~ 16.1 kg, 30.6 ~ 35.5 lb)
  • Page 360 SPEC MAINTENANCE SPECIFICATIONS Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Piston ring: Sectional sketch Top ring Ring type Barrel Dimensions (B × T) 1.00 × 2.80 mm (0.039 × 0.110 in) 2nd ring Ring type Taper Dimensions (B × T) 1.00 × 2.90 mm (0.039 × 0.114 in) Oil ring Dimensions (B ×...
  • Page 361 SPEC MAINTENANCE SPECIFICATIONS Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Bypass 1 (B.P.1) (B.P.2) (B.P.3) (B.P.4) (B.P.5) Pilot screw (P.S) 2 turns out Throttle valve (Th.V) 1020-B70-B0 (θ = 10°) Valve seat size (V.S) Starter jet (G.S) Float height (F.H) 16 mm (0.630 in) Fuel level (below the line on the float cham- 0.2 ~ 2.2 mm (0.008 ~ 0.087 in) ber) Throttle cable free play...

  • Page 362: Power Train

    SPEC MAINTENANCE SPECIFICATIONS POWER TRAIN Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Transmission: Type V-belt automatic Range of ratio 3.8 ~ 1.0 : 1 Engagement speed r/min 3,300 ~ 3,700 r/min (RS90/RS90R) 3,400 ~ 3,800 r/min (RSG90) 3,800 ~ 4,200 r/min (RS90M) 3,000 ~ 3,400 r/min (RST90 “USA/Canada”) 2,800 ~ 3,200 r/min (RST90 “Europe”/RST90TF) Shift r/min 8,250 ~ 8,750 r/min...
  • Page 363 SPEC MAINTENANCE SPECIFICATIONS Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Free length 87.4 mm (3.44 in) (RS90/RS90R) 93.4 mm (3.68 in) (RSG90) 89.8 mm (3.54 in) (RS90M) 89.0 mm (3.50 in) (RST90 “USA/Canada”) 89.4 mm (3.52 in) (RST90 “Europe”/RST90TF) Set length 73.4 mm (2.89 in) Primary sheave weight arm: Part number (with bush) 8ES-17605-00 (RS90/RS90R/RSG90/RST90 “USA/...
  • Page 364 SPEC MAINTENANCE SPECIFICATIONS Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Hole position Sheave side-spring side (twist angle) 3-3 (60°) (RS90/RS90R/RSG90/RST90 “USA/Canada”) 1-6 (70°) (RS90M/RST90 “Europe”/RST90TF) Spring rate 12.3 N/mm (1.26 kg/mm, 70.56 lb/in) (RS90/RS90R/ RSG90/RS90M/RST90 “USA/Canada”) 13.5 N/mm (1.37 kg/mm, 76.72 lb/in) (RST90 “Europe”/ RST90TF) Number of coils 5.53 (RS90/RS90R/RSG90/RS90M/RST90 “USA/ Canada”)
  • Page 365 SPEC MAINTENANCE SPECIFICATIONS Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Thickness “A” 5.1 mm (0.20 in) (RS90/RS90R/RSG90/RST90/RST90TF) 5.8 mm (0.23 in) (RS90M) Height “B” 31.8 mm (1.25 in) (RS90/RS90R/RSG90/RST90/ RST90TF) 50.8 mm (2.00 in) (RS90M) Track deflection at 100 N (10 kg, 22 lb) 30 ~ 35 mm (1.18 ~ 1.38 in) (RS90/RS90R/RS90M/RST90/ RST90TF) 25 ~ 30 mm (0.98 ~ 1.18 in) (RSG90) Slide rail suspension (rear suspension):...
  • Page 366 SPEC MAINTENANCE SPECIFICATIONS Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Suspension setting position: Hook setting length * (Standard) 14.5 ~ 15.5 mm (0.571 ~ 0.610 in) (RSG90) (Maximum) 35 mm (1.37 in) (RSG90) (Minimum) 10 mm (0.40 in) (RSG90) Full rate adjusting position ** B (RSG90) Shock absorber: Damping force Front Extension...
  • Page 367 SPEC MAINTENANCE SPECIFICATIONS Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Compression 460 N/0.3 m/s (46.9 kg/0.3 m/s, 103.5 lb/0.3 m/s) (RS90/ RS90R “USA/Canada”) 710 N/0.3 m/s (72.4 kg/0.3 m/s, 159.6 lb/0.3 m/s) (RS90R “Europe”) 930 N/0.3 m/s (94.8 kg/0.3 m/s, 209.0 lb/0.3 m/s) (RSG90 “USA/Canada”) 1,230 N/0.3 m/s (125.4 kg/0.3 m/s, 276.5 lb/0.3 m/s) (RSG90 “Europe”) 460 N/0.3 m/s (46.9 kg/0.3 m/s, 103.4 lb/0.3 m/s) (RS90M)

  • Page 368: Chassis

    SPEC MAINTENANCE SPECIFICATIONS CHASSIS Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Frame: Frame material Monocoque (Aluminum) Seat height 720 mm (28.3 in) (RS90/RS90R/RSG90/RS90M) 700 mm (27.6 in) (RST90/RST90TF) Luggage box location Front Steering: Lock-to-lock angle (left) 29.0° (R ski) 34.5° (L ski) (RS90/RS90R/RSG90/RST90/ RST90TF) 30.1° (R ski) 35.0° (L ski) (RS90M) (right) 34.5°...
  • Page 369 SPEC MAINTENANCE SPECIFICATIONS Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Shock absorber: Damping force Extension 1,400 N/0.3 m/s (142.8 kg/0.3 m/s, 315.1 lb/0.3 m/s) (RS90/RS90R/RSG90) 840 N/0.3 m/s (85.7 kg/0.3 m/s, 189.0 lb/0.3 m/s) (RS90M) 1,180 N/0.3 m/s (120.3 kg/0.3 m/s, 265.2 lb/0.3 m/s) (RST90/RST90TF) Compression 570 N/0.3 m/s (58.1 kg/0.3 m/s, 128.1 lb/0.3 m/s) (RS90/ RS90R/RSG90/RS90M)

  • Page 370: Electrical

    SPEC MAINTENANCE SPECIFICATIONS ELECTRICAL Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF Voltage 12 V Ignition system: Ignition timing (B.T.D.C.) 5° at 1,400 r/min Advanced type Digital type Ignition coil: Model/Manufacturer F6T55873/MITSUBISHI Ignition spark gap 6.0 mm (0.24 in) 1.19 ~ 1.61 Ω at 20 °C (68 °F) Primary coil resistance Secondary coil resistance 8.5 ~ 11.5 kΩ...
  • Page 371 SPEC MAINTENANCE SPECIFICATIONS Model RS90/RS90R/RSG90/RS90M/RST90/RST90TF T.P.S. (throttle position sensor): Manufacturer KEIHIN Resistance 4 ~ 6 kΩ at 20 °C (68 °F) (Blue – Black) 0 ~ 4 kΩ at 20 °C (68 °F) (Yellow – Black) Oil level switch: Model/Manufacturer 8FA/ASTI Fuel sender: Model/Manufacturer...

  • Page 372: High Altitude Settings

    SPEC MAINTENANCE SPECIFICATIONS HIGH ALTITUDE SETTINGS Temperature –30 °C –10 °C 10 °C (–22 °F) (–14 °F) (50 °F) Altitude Idling speed (r/min) 0 ~ 200 m #150 #148 #148 1,350 (0 ~ 700 ft) 200 ~ 1,500 m #148 #148 #145 1,350...

  • Page 373: Tightening Torque

    SPEC TIGHTENING TORQUE TIGHTENING TORQUE ENGINE Tightening torque Parts to be tightened Remarks m · kg ft · lb Spark plug Cylinder head bolt (M10 × 1.25) See NOTE. Cylinder head bolt Camshaft cap and cylinder head Apply the engine oil. Cylinder head cover Camshaft and camshaft sprocket Timing chain tensioner...
  • Page 374 SPEC TIGHTENING TORQUE Tightening torque Parts to be tightened Remarks m · kg ft · lb Primary sheave drive shaft assembly bolt Connecting rod and cap See NOTE. Balancer ® Balancer shaft bearing retainer Apply LOCTITE A.C. magneto rotor Apply the engine oil. A.C.

  • Page 375: Power Train

    SPEC TIGHTENING TORQUE POWER TRAIN Tightening torque Parts to be tightened Remarks m · kg ft · lb Primary sheave See NOTE. Spider and sliding sheave Left-hand thread. ® Apply LOCTITE Primary sheave cap and sliding sheave Roller and weight (primary sheave) ®...
  • Page 376 SPEC TIGHTENING TORQUE Tightening torque Parts to be tightened Remarks m · kg ft · lb Stopper band Hook and front pivot arm (RSG90) Front suspension bracket and sliding frame (RSG90) Apply grease* ® Bracket bolt (rear) (RSG90) Apply LOCTITE Shaft and sliding frame (RS90/RS90R/RS90M/RST90/ RST90TF)
  • Page 377 SPEC TIGHTENING TORQUE Tightening torque Parts to be tightened Remarks m · kg ft · lb Rear axle (RS90/RS90R/RS90M/RST90/ RST90TF) Rear axle (RST90TF) ® Set bolt (front axle) Apply LOCTITE Speed sensor Bearing holder Gear unit (speed sensor) *: ESSO beacon 325 grease or Aeroshell grease #7A NOTE: Tightening steps: 1.

  • Page 378: Chassis

    SPEC TIGHTENING TORQUE CHASSIS Tightening torque Parts to be tightened Remarks m · kg ft · lb Handlebar holder Steering column 1 (front) Steering column 1 (rear upper) Steering column 1 (rear lower) Steering column 2 (upper) Steering column 2 (lower) Steering column 2 and steering shaft ®...

  • Page 379: General Torque Specifications

    GENERAL TORQUE SPECIFICATIONS/ SPEC DEFINITION OF UNITS GENERAL TORQUE General torque SPECIFICATIONS specifications (nut) (bolt) This chart specifies torque for standard fasteners m · kg ft · lb with standard I.S.O. pitch threads. Torque specifi- 10 mm 6 mm cations for special components or assemblies are 12 mm 8 mm included in the applicable sections of this book.

  • Page 380: Cable Routing

    SPEC CABLE ROUTING 1 2 3 h i j 9-28...
  • Page 381 SPEC CABLE ROUTING CABLE ROUTING 1 Positive battery lead 2 Negative battery lead 3 Wire harness 4 Fasten the A.C. magneto lead and wire harness with the plastic band. 5 Negative battery lead coupler 6 Route the negative battery leads under the starter relay.
  • Page 382 SPEC CABLE ROUTING 1 2 3 h i j 9-30...
  • Page 383 SPEC CABLE ROUTING P Right handlebar switch lead cou- plers Q Thumb warmer adjustment switch lead coupler R Grip warmer lead connectors S To the tail/brake light T Headlight beam switch coupler U Grip warmer switch lead coupler V Brake light switch lead coupler W Route the starter cable over the left handlebar switch lead.
  • Page 384 SPEC CABLE ROUTING 1 2 3 h i j 9-32...
  • Page 385 SPEC CABLE ROUTING f To the headlights and meter assembly g Load control relay h Headlight relay i Carburetor heater relay j Back buzzer (RS90R/RSG90/ RST90/RST90TF) k Nut l Bolt m Install the starter motor lead ter- minal so that the terminal is bent upward.
  • Page 386 SPEC CABLE ROUTING 9-34...
  • Page 387 SPEC CABLE ROUTING 1 Headlight sub-wire harness 2 Fasten the headlight sub-wire harness at the white tape with the holder on the shroud. 3 Fasten the headlight sub-wire harness with the holder. 4 Fasten the headlight sub-wire harness with the clamp. 5 Fasten the headlight sub-wire harness at the white tape with the plastic band.
  • Page 388 SPEC CABLE ROUTING 2 3 4 5 6 7 8 9 0 A 9-36...
  • Page 389 SPEC CABLE ROUTING 1 Right handlebar switch 2 Fasten the right handlebar switch lead, thumb warmer adjustment switch lead, thumb warmer lead, and grip warmer lead with the plastic band. Do not fasten the throttle cable. 3 Fasten the wire harness and main switch lead with the plastic band.
  • Page 390 SPEC CABLE ROUTING 2 3 4 5 6 7 8 9 0 A 9-38...
  • Page 391 SPEC CABLE ROUTING F Fuel sender terminal cover G Fasten the speed sensor lead only. (RS90/RS90R/RSG90/ RS90M) Fasten the speed sensor lead and passenger grip warmer relay lead with the holder. (RST90/ RST90TF) H Fasten the hose protector of the fuel tank breather hose.
  • Page 392 SPEC CABLE ROUTING 2 3 4 5 6 7 8 9 0 A 9-40...
  • Page 393 SPEC CABLE ROUTING V Fasten the wire harness with the plastic band. The buckle and the end of the plastic band should not be between the wire harness and the shroud. W Fasten the wire harness and fuel tank breather hose together with the clip.
  • Page 394 SPEC CABLE ROUTING 9-42...
  • Page 395 SPEC CABLE ROUTING 1 Headlight sub-wire harness 2 Install the ground lead terminal with the rectifier/regulator upper bolt. 3 Oil tank outlet hose 4 Fasten the starter motor lead and A.C. magneto lead with the holder. 5 Starter motor lead 6 Place the end of the coolant res- ervoir breather hose between the engine and the heat exchanger.
  • Page 396 SPEC CABLE ROUTING 9-44...
  • Page 397 SPEC CABLE ROUTING I The fastener of the screw clamp should be towards the front of the snowmobile with the screw- head facing outward. J Fasten the coolant hose 22 at the white paint mark with the plastic band. Install the plastic band with the buckle facing out- ward and the end facing towards the front of the snowmobile.
  • Page 398 SPEC CABLE ROUTING 9-46...
  • Page 399 SPEC CABLE ROUTING 1 Fuel pumps 2 Face the ends of each clamp outward. 3 Fuel hoses 4 Coolant reservoir 5 Fasten the fuel tank breather hose and speed sensor lead with the holder. Secure the frame cross member and the holder to the frame with the nut and bolt.
  • Page 400 SPEC CABLE ROUTING 9-48...
  • Page 401 SPEC CABLE ROUTING 1 To the rectifier/regulator 2 A.C. magneto lead 3 Negative battery lead 4 Positive battery lead 5 Ignitor unit 6 Ignitor unit bracket 7 Air filter case latch 8 Battery band 9 Battery cover 0 To the carburetor A Wire harness B Battery bracket C Frame cross member...
  • Page 402 SPEC CABLE ROUTING 9-50...
  • Page 403 SPEC CABLE ROUTING 1 Forward 2 Wire harness 3 Battery bracket 4 To the air filter case 5 A.C. magneto lead 6 Route the crankcase breather hose between the wire harness and the A.C. magneto lead, and then under the battery bracket. 7 Crankcase breather hose 9-51...
  • Page 404 SPEC CABLE ROUTING 9-52...
  • Page 405 SPEC CABLE ROUTING RST90/RST90TF only 1 Connect the wire harness cou- pler to the tail/brake light sub- wire harness coupler on the out- side of the bracket. 2 Passenger grip warmer switch 3 Connect the passenger grip warmer couplers under the pas- senger seat base.
  • Page 406 WIRING DIAGRAM RS90/RS90R/RSG90/RS90M/RST90/RST90TF È É (BLACK) G L/Y G/B Ch B Dg R/B B (BLACK) (BLACK) Lg/W B/W Y/W Br/W Lg Br/Y Y/R G Lg/L Y/B Br/L B HEADLIGHT HEADLIGHT TAIL/BRAKE LIGHT TAIL/BRAKE LIGHT SUB-WIRE SUB-WIRE SUB-WIRE WIRE HARNESS SUB-WIRE WIRE HARNESS SUB-WIRE WIRE HARNESS...
  • Page 407 WIRING DIAGRAM COLOR CODE B ..... Black Br .... Brown Ch ... Chocolate Dg ... Dark green G ..... Green Gy ... Gray L....Blue Lg.... Light green O ..... Orange P ..... Pink R ..... Red W .... White Y .....
  • Page 408 1 Pickup coil 2 A.C. magneto 3 Rectifier/regulator 4 Main switch 5 Load control relay 6 Main fuse 7 Starter relay 8 Starter motor 9 Battery 0 Engine stop switch A Throttle switch B Carburetor heater relay C Carburetor ground D Carburetor heater E Grip warmer F Thumb warmer...
  • Page 409 YAMAHA MOTOR CO., LTD. PRINTED ON RECYCLED PAPER PRINTED IN U.S.A. 2004.05 CR...

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