Yamaha YZ125 2022 Owner's Service Manual
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Yamaha YZ125 2022 Owner's Service Manual

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2022
OWNER'S SERVICE MANUAL
YZ125
Read this manual carefully before operating this vehicle.
YZ125N2
B4X-2819U-10 ■
LIT-11626-35-29

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  • Page 1 2022 OWNER’S SERVICE MANUAL YZ125 Read this manual carefully before operating this vehicle. YZ125N2 B4X-2819U-10 ■ LIT-11626-35-29...
  • Page 2 EAM20161 Read this manual carefully Operating, servicing and maintaining a passenger vehicle or off-road vehicle can expose you to chemicals including engine exhaust, carbon monoxide, phthalates, and lead, which are known to the State of California to cause cancer and birth defects or other reproductive harm.
  • Page 3 EAM20080 YZ125N2 OWNER’S SERVICE MANUAL ©2022 by Yamaha Motor Corporation, U.S.A. First edition, June 2021 All rights reserved. Any reproduction or unauthorized use without the written permission of Yamaha Motor Corporation, U.S.A. is expressly prohibited. P/N. LIT-11626-35-29...
  • Page 4 EAM20180 IMPORTANT Congratulations on your purchase of a Yamaha YZ series. This model is the culmination of Yamaha’s vast experience in the production of pacesetting racing machines. It represents the highest grade of craftsmanship and reliability that have made Yamaha a leader.
  • Page 5 EAM20162 YAMAHA MOTOR CORPORATION, U.S.A. YZ MOTORCYCLE LIMITED WARRANTY...
  • Page 6 EAM20082 HOW TO USE THIS MANUAL In this manual, descriptions of installation, removal, disassembly, assembly, check, and adjustment procedures are laid out with the individual steps in sequential order. • The manual is divided into chapters and each chapter is divided into sections. The current section title “1”...
  • Page 7 EAM20083 SYMBOLS The following symbols are used in this manual for easier understanding. The following symbols are not relevant to every vehicle. SYMBOL DEFINITION SYMBOL DEFINITION Serviceable with engine mounted Gear oil Filling fluid Molybdenum disulfide oil Lubricant Brake fluid Special tool Wheel bearing grease Tightening torque...

  • Page 9: Table Of Contents

    TABLE OF CONTENTS EAM10003 GENERAL INFORMATION SPECIFICATIONS PERIODIC CHECKS AND ADJUSTMENTS CHASSIS ENGINE COOLING SYSTEM FUEL SYSTEM ELECTRICAL SYSTEM TROUBLESHOOTING TUNING...
  • Page 11 GENERAL INFORMATION SAFETY INFORMATION ..................1-1 FOR SAFETY, BE SURE TO OBEY THE FOLLOWING:......1-1 LOCATION OF IMPORTANT LABELS.............1-4 DESCRIPTION....................1-5 IDENTIFICATION ....................1-6 VEHICLE IDENTIFICATION NUMBER ............1-6 ENGINE SERIAL NUMBER................1-6 INCLUDED PARTS ...................1-7 SIDESTAND ....................1-7 NIPPLE WRENCH ..................1-7 VALVE JOINT .....................1-7 COLLAR (tool for YPVS) ................1-7 IMPORTANT INFORMATION ................1-8 PREPARATION FOR REMOVAL AND DISASSEMBLY ......1-8 REPLACEMENT PARTS ................1-8...
  • Page 12 MAINTENANCE AFTER BREAK-IN ..............1-20 MAJOR MAINTENANCE ................1-20 AIR FILTER MAINTENANCE ..............1-20 TORQUE-CHECK POINTS................1-21 MOTORCYCLE CARE AND STORAGE............1-23 CARE ......................1-23 STORAGE ....................1-24...

  • Page 13: Safety Information

    Yamaha ma- accidents. Many accidents have been chine, and take care to maintain it properly and caused by an automobile driver who did not operate it safely.
  • Page 14 1. Always wear an approved helmet. Yamaha can neither endorse nor recommend 2. Wear a face shield or goggles. Wind in your the use of accessories not sold by Yamaha or unprotected eyes could contribute to an im- modifications not specifically recommended by...
  • Page 15 SAFETY INFORMATION Aftermarket Tires and Rims The tires and rims that came with your motorcy- cle were designed to match the performance ca- pabilities and to provide the best combination of handling, braking, and comfort. Other tires, rims, sizes, and combinations may not be appropriate. Refer to “CHECKING THE TIRES”...

  • Page 16: Location Of Important Labels

    LOCATION OF IMPORTANT LABELS EAM20085 LOCATION OF IMPORTANT LABELS Please read the following important labels carefully before operating this vehicle. 3, 4...

  • Page 17: Description

    DESCRIPTION EAM20086 DESCRIPTION 13 14 15 11.Check bolt (Transmission oil level) 1. Clutch lever 12.Rear brake pedal 2. Engine stop switch 13.Valve joint 3. Front brake lever 4. Throttle grip 14.Fuel cock 15.Starter knob 5. Radiator cap 6. Fuel tank cap 16.Drive chain 17.Air filter 7.

  • Page 18: Identification

    There are two significant reasons for knowing the serial number of your vehicle: 1. When ordering parts, you can give the num- ber to your Yamaha dealer for positive identi- fication of the model you own. 2. If your vehicle is stolen, the authorities will need the number to search for and identify your vehicle.

  • Page 19: Included Parts

    INCLUDED PARTS EAM20088 INCLUDED PARTS EAM30372 SIDESTAND This sidestand “1” is used to support only the machine when standing or transporting it. EWA20260 WARNING • Never apply additional force to the sides- tand. • Remove this sidestand before starting out. EAM30615 COLLAR (tool for YPVS) This collar “1”...

  • Page 20: Important Information

    2. Use proper special tools and equipment. Re- used for repair of the vehicle, including periodic fer to “SPECIAL TOOLS” on page 1-12. replacement parts, are new YAMAHA genuine parts and recommended parts. Do not use any used parts, because these may...

  • Page 21: Lock Washers/Plates And Cotter Pins

    IMPORTANT INFORMATION 1. Oil 2. Lip 3. Spring 4. Grease EAM30012 LOCK WASHERS/PLATES AND COTTER PINS After removal, replace lock washers/plates “1” and cotter pins with new ones. After the bolt or nut has been tightened to specification, firmly bend the lock tabs along a flat of the bolt or nut. EAM30014 CIRCLIPS When assembling parts, always use new cir-...

  • Page 22: Basic Service Information

    BASIC SERVICE INFORMATION • There are many types of coupler locks; EAM20120 BASIC SERVICE INFORMATION therefore, be sure to check the type of cou- pler lock before disconnecting the coupler. EAM30181 ELECTRICAL SYSTEM Checking the electrical system ECA14371 NOTICE Never insert the tester probes into the cou- pler terminal slots.
  • Page 23 BASIC SERVICE INFORMATION • If the pin “1” on the terminal is flattened, bend it up. • After disassembling or assembling a coupler, pull on the leads to make sure that they are in- stalled securely. 5. Check: • No continuity Digital circuit tester (CD732) 90890-03243 Model 88 Multimeter with tachom-...

  • Page 24: Special Tools

    SPECIAL TOOLS EAM20121 SPECIAL TOOLS The following special tools are required for accurate and complete adjustment and assembly. Using the correct special tool will help prevent damage caused by the use of improper tools or improvised tech- niques. The shape and tool number used for the special tool differ by country, so two types are provid- ed.
  • Page 25 90890-01189 Flywheel puller YM-01189 Clutch holder 5-30, 5-32 90890-04199 Universal clutch holder YM-91042 Thickness gauge 5-30 90890-03268 Feeler gauge set YU-26900-9 Flywheel puller 5-40 90890-01362 Heavy duty puller YU-33270-B Yamaha bond No. 1215 5-41 90890-85505 Three bond No. 1215® 1-13...
  • Page 26 SPECIAL TOOLS Reference Tool name/Tool No. Illustration pages Crankshaft installer pot 5-41, 5-44 90890-01274 Installing pot YU-90058 YU-90058/YU-90059 Crankshaft installer bolt 5-41, 5-44 90890-01275 Bolt YU-90060 Adapter (M8) 5-41 90890-01499 Adapter (M8) YM-01499 Crankcase separating tool 5-44 90890-01135 Crankcase separator YU-01135-B Adapter (M12) 5-44...
  • Page 27 SPECIAL TOOLS Reference Tool name/Tool No. Illustration pages Radiator cap tester 6-3, 6-3 90890-01325 Mityvac cooling system tester kit YU-24460-A YU-24460-A Radiator cap tester adapter 6-3, 6-3 90890-01352 Pressure tester adapter YU-33984 YU-33984 Ignition checker 90890-06754 Oppama pet–4000 spark checker YM-34487 1-15...

  • Page 28: Instrument And Control Functions

    INSTRUMENT AND CONTROL FUNCTIONS EAM20181 INSTRUMENT AND CONTROL FUNCTIONS EAM30182 ENGINE STOP SWITCH The engine stop switch “1” is located on the left handlebar. Continue pushing the engine stop switch till the engine comes to a stop. EAM30188 FRONT BRAKE LEVER The front brake lever “1”...

  • Page 29: Starter Knob (Choke)

    INSTRUMENT AND CONTROL FUNCTIONS in this position. EAM30444 STARTER KNOB (CHOKE) When cold, the engine requires a richer air-fuel mixture for starting. A separate starter circuit, which is controlled by the starter knob “1”, sup- plies this mixture. Pull the starter knob out to open the circuit for starting.

  • Page 30: Starting And Break-In

    STARTING AND BREAK-IN 4. Run the engine at idle or slightly higher until it EAM20123 STARTING AND BREAK-IN warms up: this usually takes about one or two minutes. EAM30538 5. The engine is warmed up when it responds FUEL AND ENGINE MIXING OIL normally to the throttle with the starter knob Mix oil with the gas at the ratio specified below.
  • Page 31 STARTING AND BREAK-IN ECA25821 NOTICE After a break-in or after each race, always check the points shown in “TORQUE- CHECK POINTS” for tightening torques and retighten them. Also when the following parts are replaced, a break-in is required. • Cylinder and Crankshaft: A break-in is re- quired for about an hour.

  • Page 32: Maintenance After Break-In

    Disassemble the carburetor and clean the AIR FILTER MAINTENANCE small holes, blowing them with compressed Apply the Yamaha foam air filter oil or other qual- air. ity foam air filter oil to the element. (Excess oil in • CDI magneto...

  • Page 33: Torque-Check Points

    TORQUE-CHECK POINTS EAM20125 TORQUE-CHECK POINTS Frame construction Combined seat and fuel tank Fuel tank to frame Frame to rear frame Engine mounting Frame to engine Engine bracket to engine Engine bracket to frame Seat Seat to frame Steering Steering stem to handlebar Steering stem to frame Steering stem to upper bracket Upper bracket to handlebar...
  • Page 34 TORQUE-CHECK POINTS Plastic cover Tightening of front fender Tightening of fork leg protector Tightening of air scoop Left cover to rear frame Tightening of side cover Tightening of rear fender Tightening of mud flap Tightening of rear brake disc cover Tightening of rear brake caliper cover Concerning the tightening torque, refer to “TIGHTENING TORQUES”...

  • Page 35: Motorcycle Care And Storage

    MOTORCYCLE CARE AND STORAGE ucts are used on hard-to-remove dirt, do EAM20126 MOTORCYCLE CARE AND STOR- not leave the cleaner on the affected area any longer than instructed. Also, thorough- ly rinse the area off with water, immediately dry it, and then apply a corrosion protec- EAM30200 CARE tion spray.

  • Page 36: Storage

    Salt sprayed on roads in the winter may remain well into spring. • Consult a Yamaha dealer for advice on what 1. Clean the motorcycle with cold water and a products to use.
  • Page 37 MOTORCYCLE CARE AND STORAGE stored. Long-term Before storing your motorcycle for several months: 1. Follow all the instructions in “CARE” on page 1-23. 2. Drain the fuel tank, fuel lines, and the carbu- retor float bowl. 3. Perform the following steps to protect the cyl- inder, piston rings, etc.
  • Page 38 MOTORCYCLE CARE AND STORAGE 1-26...

  • Page 39: Specifications

    SPECIFICATIONS GENERAL SPECIFICATIONS ................2-1 ENGINE SPECIFICATIONS................2-2 CHASSIS SPECIFICATIONS................2-5 ELECTRICAL SPECIFICATIONS..............2-8 TIGHTENING TORQUES..................2-9 GENERAL TIGHTENING TORQUE SPECIFICATIONS ......2-9 ENGINE TIGHTENING TORQUES ............2-10 CHASSIS TIGHTENING TORQUES ............2-11 CABLE ROUTING DIAGRAM ................2-15...

  • Page 40: General Specifications

    GENERAL SPECIFICATIONS EAM20127 GENERAL SPECIFICATIONS Model Model B4X1 B4X5 Dimensions Overall length 2135 mm (84.1 in) Overall width 825 mm (32.5 in) Overall height 1295 mm (51.0 in) Seat height 980 mm (38.6 in) Wheelbase 1445 mm (56.9 in) Ground clearance 365 mm (14.37 in) Weight Curb weight...

  • Page 41: Engine Specifications

    ENGINE SPECIFICATIONS EAM20128 ENGINE SPECIFICATIONS Engine Combustion cycle 2-stroke Cooling system Liquid cooled Induction system Reed valve Displacement 125 cm³ Number of cylinders Single cylinder Bore  stroke 54.0  54.5 mm (2.13  2.15 in) Compression ratio 8.2–10.1 : 1 Starting system Kickstarter Fuel...
  • Page 42 3.769 (49/13) Final drive Chain Air filter Air filter element Wet element Air filter oil grade Yamaha foam air filter oil or other quality foam air filter oil Carburetor Type  quantity PWK38S  1 ID mark B4X1 00 Main jet...
  • Page 43 ENGINE SPECIFICATIONS Reed valve Thickness 0.400 mm (0.0157 in) Valve bending limit 0.2 mm (0.01 in)
  • Page 44 CHASSIS SPECIFICATIONS EAM20129 CHASSIS SPECIFICATIONS Chassis 26.0  Caster angle Trail 109 mm (4.3 in) Front wheel Wheel type Spoke wheel Rim size 21 x 1.60 Radial wheel runout limit 2.0 mm (0.08 in) Lateral wheel runout limit 2.0 mm (0.08 in) Wheel axle bending limit 0.50 mm (0.02 in) Rear wheel...
  • Page 45 Fork spring free length limit 492.0 mm (19.37 in) Inner tube bending limit 0.2 mm (0.01 in) Recommended oil Yamaha Suspension Oil S1 Quantity (left) 500.0 cm³ (16.91 US oz, 17.64 Imp.oz) Quantity (right) 500.0 cm³ (16.91 US oz, 17.64 Imp.oz)

  • Page 46: Chassis Specifications

    CHASSIS SPECIFICATIONS Adjustment value from the start position (Hard) Slow compression damping Unit for adjustment Click Adjustment value from the start position (Soft) Adjustment value from the start position (STD) Adjustment value from the start position (Hard) Drive chain Size Chain type Non-sealed type Number of links...

  • Page 47: Electrical Specifications

    ELECTRICAL SPECIFICATIONS EAM20130 ELECTRICAL SPECIFICATIONS Ignition system Ignition system Ignition timing (B.T.D.C.) 0.50 mm (0.02 in) 248.0–372.0  Pickup coil resistance 720.0–1080.0  Charging coil 1 resistance 44.0–66.0  Charging coil 2 resistance Ignition coil 0.24–0.36  Primary coil resistance Secondary coil resistance 5.68–8.52 k...

  • Page 48: Tightening Torques

    TIGHTENING TORQUES EAM20131 TIGHTENING TORQUES EAM30205 GENERAL TIGHTENING TORQUE SPECIFICATIONS This chart specifies tightening torques for stan- dard fasteners with a standard ISO thread pitch. Tightening torque specifications for special com- ponents or assemblies are provided for each chapter of this manual. To avoid warpage, tight- en multi-fastener assemblies in a crisscross pat- tern and progressive stages until the specified tightening torque is reached.

  • Page 49: Engine Tightening Torques

    TIGHTENING TORQUES EAM30203 ENGINE TIGHTENING TORQUES - marked portion shall be checked for torque tightening after break-in or before each race. Thread Item Q’ty Tightening torques Remarks size Spark plug M14S 20 N·m (2.0 kgf·m, 15 lb·ft) Cylinder head nut 28 N·m (2.8 kgf·m, 21 lb·ft) Cylinder head stud bolt 13 N·m (1.3 kgf·m, 9.6 lb·ft)

  • Page 50: Chassis Tightening Torques

    TIGHTENING TORQUES Thread Item Q’ty Tightening torques Remarks size Oil drain bolt 20 N·m (2.0 kgf·m, 15 lb·ft) Kickstarter lever 10 N·m (1.0 kgf·m, 7.4 lb·ft) Clutch cover bolt 10 N·m (1.0 kgf·m, 7.4 lb·ft) Primary drive gear bolt 48 N·m (4.8 kgf·m, 35 lb·ft) Use a lock Clutch boss nut 80 N·m (8.0 kgf·m, 59 lb·ft)
  • Page 51 TIGHTENING TORQUES Thread Item Q’ty Tightening torques Remarks size Base valve (front fork) 29 N·m (2.9 kgf·m, 21 lb·ft) Adjuster (damper assembly) 29 N·m (2.9 kgf·m, 21 lb·ft) Bleed screw (front fork) 1.3 N·m (0.13 kgf·m, 0.95 lb·ft) Front fork protector bolt 5 N·m (0.5 kgf·m, 3.7 lb·ft) ...
  • Page 52 TIGHTENING TORQUES Thread Item Q’ty Tightening torques Remarks size Rear wheel sprocket nut 42 N·m (4.2 kgf·m, 31 lb·ft)  Rear brake disc cover bolt 10 N·m (1.0 kgf·m, 7.4 lb·ft)  Rear brake caliper protector bolt 7 N·m (0.7 kgf·m, 5.2 lb·ft) ...
  • Page 53 TIGHTENING TORQUES Thread Item Q’ty Tightening torques Remarks size Side cover bolt (front side) 7 N·m (0.7 kgf·m, 5.2 lb·ft)  Side cover bolt (rear side) 9 N·m (0.9 kgf·m, 6.6 lb·ft)  Seat bolt 11 N·m (1.1 kgf·m, 8.1 lb·ft) ...

  • Page 54: Cable Routing Diagram

    CABLE ROUTING DIAGRAM EAM20152 CABLE ROUTING DIAGRAM Frame and engine (left side view) 2-15...
  • Page 55 CABLE ROUTING DIAGRAM K. Pass the radiator breather hose and YPVS 1. Engine stop switch lead breather hose on the outside of the engine 2. Throttle cable bracket and then inside of the down tube. 3. Clutch cable Then pass the radiator breather hose inside 4.
  • Page 56 CABLE ROUTING DIAGRAM Frame and engine (right side view) 2-17...
  • Page 57 CABLE ROUTING DIAGRAM J. Pass the CDI magneto lead and radiator 1. High tension cord breather hose between the frame and the 2. Clamp radiator (right). 3. Ignition coil lead K. Place the clamp end so that it is located out- 4.
  • Page 58 CABLE ROUTING DIAGRAM Handlebar (front view) 2-19...
  • Page 59 CABLE ROUTING DIAGRAM 1. Brake hose 2. Master cylinder 3. Engine stop switch lead 4. Engine stop switch 5. Throttle cable 6. Clutch cable 7. Clamp 8. Cable guide A. Install the brake hose so that its pipe portion directs as shown and lightly touches the pro- jection on the master cylinder, while the white paint side faces to the front of the vehicle.
  • Page 60 CABLE ROUTING DIAGRAM Rear brake (right side view) 2-21...
  • Page 61 CABLE ROUTING DIAGRAM 1. Protector 2. Rear brake caliper 3. Bleed screw 4. Gasket 5. Rear brake hose 6. Brake pedal 7. Rear brake master cylinder assembly 8. Spring 9. Frame A. Install the spring as shown in the illustration. B.
  • Page 62 CABLE ROUTING DIAGRAM 2-23...

  • Page 63: Periodic Checks And Adjustments

    PERIODIC CHECKS AND ADJUSTMENTS MAINTENANCE INTERVALS ................3-1 MAINTENANCE INTERVALS..............3-1 PRE-OPERATION INSPECTION AND MAINTENANCE .........3-4 GENERAL INSPECTION AND MAINTENANCE ........3-4 ENGINE......................3-5 ADJUSTING THE PILOT AIR SCREW ............3-5 CHECKING THE ENGINE IDLING SPEED..........3-5 CHECKING THE THROTTLE GRIP ............3-5 CHECKING THE SPARK PLUG..............3-5 CHECKING THE TRANSMISSION OIL LEVEL .........3-6 CHANGING THE TRANSMISSION OIL .............3-6 ADJUSTING THE CLUTCH LEVER FREE PLAY ........3-7...
  • Page 64 CHECKING AND LUBRICATING THE CABLES........3-24 LUBRICATING THE BRAKE LEVER ............3-24 LUBRICATING THE CLUTCH LEVER .............3-24 LUBRICATING THE PEDAL..............3-24 ELECTRICAL SYSTEM..................3-25 CHECKING THE IGNITION TIMING ............3-25...

  • Page 65: Maintenance Intervals

    (e.g., rain, dirt, etc.). Therefore, earlier inspection is required by reference to the list below. Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools, data and technical skills.
  • Page 66  • Check chain slack, alignment and condition.   • Adjust and thoroughly lubricate 16 * Drive chain chain with Yamaha chain and cable lube or equivalent.  • Replace. • Check coolant level and for leak-  ...
  • Page 67 MAINTENANCE INTERVALS Every Every Every After race third race fifth race Item Routine break-in (about 2.5 (about 7.5 (about 12.5 required hours) hours) hours) • Check operation and for oil leak- age. • Adjust if necessary.   • Clean dust seal and lubricate with lithium-soap-based grease.

  • Page 68: Pre-Operation Inspection And Maintenance

    PRE-OPERATION INSPECTION AND MAINTENANCE EAM20134 PRE-OPERATION INSPECTION AND MAINTENANCE Before riding for break-in operation, practice or a race, make sure the machine is in good operating con- dition. Before using this machine, check the following points. EAM30209 GENERAL INSPECTION AND MAINTENANCE Item Inspect Page...

  • Page 69: Engine

    ENGINE gine idling speed should be adjusted. EAM20135 ENGINE 1. Check: • Throttle grip free play “a” EAM30607 ADJUSTING THE PILOT AIR SCREW Out of specification  Regulate. 1. Adjust: Throttle grip free play • Pilot air screw “1” 3.0–5.0 mm (0.12–0.20 in) 1 1 1 G088895 To optimize the fuel flow at a smaller throttle...

  • Page 70: Checking The Transmission Oil Level

    ENGINE into the cylinder. 3. Check: • Transmission oil level 3. Check: a. Remove the oil check bolt “1”. • Spark plug type b. Inspect the oil level. Incorrect  Change. Manufacturer/model Be sure the machine is positioned straight up NGK/BR9EVX when inspecting the oil level.

  • Page 71: Adjusting The Clutch Lever Free Play

    ENGINE Clutch lever free play 7.0–12.0 mm (0.28–0.47 in) G088887 2. Adjust: • Clutch lever free play Handlebar side a. Turn the adjuster “1” until the specified clutch lever free play is obtained. 5. Drain: • Transmission oil 6. Install: •...

  • Page 72: Adjusting The Clutch Lever Position

    4. Check: • Air filter element Damage  Replace. 5. Apply: Yamaha foam air filter oil or other quality 2. Tighten: foam air filter oil. • Locknut a. Put the air filter element into a plastic bag Locknut (clutch lever position) and drip the filter oil into the bag.

  • Page 73: Checking The Carburetor Joint

    ENGINE ECA26420 6. Install: NOTICE • Air filter guide “1” Make sure that the air filter element is prop- erly seated in the air filter case. The engine Align the projection “a” on filter guide with the should never be operated without the air fil- hole “b”...

  • Page 74: Checking The Exhaust System

    ENGINE EAM30221 CHECKING THE EXHAUST SYSTEM 1. Remove: • Exhaust pipe • Silencer Refer to “ENGINE REMOVAL” on page 5-1. 2. Check: • Exhaust pipe • Silencer Crack/damage  Replace. Refer to “ENGINE REMOVAL” on page 5-1. 6. Check: 3. Check: •...

  • Page 75: Checking The Cooling System

    ENGINE Crack/damage  Replace. Refer to “RADIATOR” on page 6-2. 3. Install: • Air scoop (left/right) • Seat • Side cover (left/right) Refer to “GENERAL CHASSIS” on page 4-1. EAM30212 CHANGING THE COOLANT EWA13030 WARNING 3. Check: A hot radiator is under pressure. Therefore, •...
  • Page 76 ENGINE Coolant drain bolt 10 N·m (1.0 kgf·m, 7.4 lb·ft) 6. Pour coolant. Recommended coolant High quality ethylene glycol anti-freeze containing anti-cor- rosion for aluminum engine Radiator (including all routes) 0.90 L (0.95 US qt, 0.79 Imp.qt) Coolant mixing ratio 1:1 (Coolant:Water) EWA13040 WARNING...

  • Page 77: Chassis

    CHASSIS air must be removed by bleeding the brake EAM20136 CHASSIS system. Air in the brake system will consid- erably reduce braking performance. EAM30479 ADJUSTING THE FRONT DISC BRAKE ECA13490 NOTICE There should be no free play at the brake lever After adjusting the brake lever position, end.

  • Page 78: Checking The Brake Fluid Level

    CHASSIS EWA19150 ECA13540 NOTICE WARNING A soft or spongy feeling in the brake pedal Brake fluid may damage painted surfaces can indicate the presence of air in the brake and plastic parts. Therefore, always clean up system. Before running, bleed the brake sys- any spilt brake fluid immediately.

  • Page 79: Checking The Rear Brake Hose

    CHASSIS 2. Check: • Reservoir float (front brake) • Brake hose clamp • Protector (rear brake) Loose connection  Tighten the clamp bolt. 3. Stand the vehicle upright and apply the front • Be careful not to spill any brake fluid or allow brake several times.

  • Page 80: Drive Chain Slack

    CHASSIS ver to contact the throttle grip or the brake pedal N (5.0 kgf, 37 lbf). to fully extend. 4. Check: • Drive chain slack “a” g. Tighten the bleed screw and then release Out of specification  Regulate. the brake lever or brake pedal. h.

  • Page 81: Checking And Adjusting The Steering Head

    CHASSIS Rear wheel axle nut 125 N·m (12.5 kgf·m, 92 lb·ft) e. Tighten the drive chain puller locknut. Drive chain puller locknut 19 N·m (1.9 kgf·m, 14 lb·ft) EAM30247 CHECKING AND ADJUSTING THE STEERING HEAD 1. Use a maintenance stand to raise the front Steering nut wrench wheel off the ground.

  • Page 82: Lubricating The Steering Head

    CHASSIS of the outer tube circumference. 5. Install: • Upper bracket 6. Remove: Refer to “STEERING HEAD” on page 4-51. • Protector • Handlebar • Dust seal “1” Refer to “HANDLEBAR” on page 4-33. ECA24330 NOTICE EAM30502 LUBRICATING THE STEERING HEAD Be careful not to damage the dust seal and 1.
  • Page 83 CHASSIS have poor stability. Compression damping • Securely support the vehicle so that there ECA24350 NOTICE is no danger of it falling over. Do not turn the adjuster forcibly beyond its Rebound damping adjusting range. ECA24340 NOTICE 1. Adjust: Do not turn the adjuster forcibly beyond its •...

  • Page 84: Checking The Rear Shock Absorber Assembly

    CHASSIS wheel off the ground. off the ground. EWA13120 EWA13120 WARNING WARNING Securely support the vehicle so that there is Securely support the vehicle so that there is no danger of it falling over. no danger of it falling over. Spring preload 2.
  • Page 85 CHASSIS Spring preload adjusting positions Rebound damping Minimum Minimum (soft) Position in which the spring is 20 click(s) in direction “b”* turned in 1.5 mm (0.06 in) from Standard its free length. 10 click(s) in direction “b”* Standard Maximum (hard) Position in which the spring is 0 click(s) in direction “b”* turned in 7.0 mm (0.28 in) from...

  • Page 86: Checking The Swingarm Operation

    CHASSIS Fast compression damping Slow compression damping Minimum (soft) Minimum (soft) 2 turn(s) in direction “b”* 20 click(s) in direction “b”* Standard Standard 1-1/2 turn(s) in direction “b”* 12 click(s) in direction “b”* Maximum (hard) Maximum (hard) 0 turn(s) in direction “b”* 0 click(s) in direction “b”* * With the adjusting screw fully turned in di- * With the adjusting screw fully turned in di-...

  • Page 87: Checking The Tires

    CHASSIS loose spoke will sound flat. EAM30243 CHECKING THE TIRES 2. Tighten: 1. Measure: • Spoke • Tire pressure (with a spoke nipple wrench “1”) Out of specification  Regulate. Tire air pressure (measured on cold tires) Front 100 kPa (1.00 kgf/cm², 15 psi) Rear 100 kPa (1.00 kgf/cm², 15 psi) •...
  • Page 88 CHASSIS Refer to “CHASSIS TIGHTENING TORQUES” on page 2-11. EAM30248 CHECKING AND LUBRICATING THE CABLES The following procedure applies to all of the in- ner and outer cables. EWA13270 WARNING Damaged outer cable may cause the cable to corrode and interfere with its movement. Re- place damaged outer cable and inner cables as soon as possible.
  • Page 89 ELECTRICAL SYSTEM Punch mark “a” on rotor should be aligned EAM20137 ELECTRICAL SYSTEM with punch mark “b” on stator. Not aligned  Adjust. EAM30255 CHECKING THE IGNITION TIMING 1. Remove: • Fuel tank Refer to “FUEL TANK” on page 7-1. •...
  • Page 90 ELECTRICAL SYSTEM 3-26...
  • Page 91 CHASSIS GENERAL CHASSIS..................4-1 REMOVING THE NUMBER PLATE ............4-2 REMOVING THE SIDE COVER ..............4-2 FRONT WHEEL ....................4-3 REMOVING THE FRONT WHEEL .............4-4 DISASSEMBLING THE FRONT WHEEL ...........4-4 CHECKING THE FRONT WHEEL .............4-4 ASSEMBLING THE FRONT WHEEL ............4-4 INSTALLING THE FRONT WHEEL ............4-5 REAR WHEEL ....................4-7 REMOVING THE REAR WHEEL ...............4-8 DISASSEMBLING THE REAR WHEEL .............4-8...
  • Page 92 HANDLEBAR....................4-33 REMOVING THE HANDLEBAR ...............4-34 CHECKING THE HANDLEBAR..............4-34 INSTALLING THE HANDLEBAR..............4-34 FRONT FORK....................4-39 REMOVING THE FRONT FORK LEGS ...........4-41 DISASSEMBLING THE FRONT FORK LEGS .........4-41 CHECKING THE FRONT FORK LEGS............4-42 ASSEMBLING THE FRONT FORK LEGS ..........4-43 INSTALLING THE FRONT FORK LEGS..........4-49 STEERING HEAD...................4-51 REMOVING THE LOWER BRACKET ............4-52 CHECKING THE STEERING HEAD ............4-52...
  • Page 93 GENERAL CHASSIS EAM20094 GENERAL CHASSIS Removing the seat and side cover Order Job/Parts to remove Q’ty Remarks Seat Air scoop (right) Air scoop (left) Side cover (left) Side cover (right) Number plate...

  • Page 94: General Chassis

    GENERAL CHASSIS EAM30371 REMOVING THE NUMBER PLATE 1. Remove: • Number plate bolt • Number plate “1” • The projection “a” is inserted into the band of the number plate. Pull the band off the projec- tion before removal. • Remove the clutch cable “2” from the cable guide “b”...

  • Page 95: Front Wheel

    FRONT WHEEL EAM20095 FRONT WHEEL Removing the front wheel 21 N ・ m (2.1 kgf ・ m, 15 lb ・ ft) 21 N ・ m (2.1 kgf ・ m, 15 lb ・ ft) 105 N ・ m (10.5 kgf ・ m, 77 lb ・ ft) 12 N ・...

  • Page 96: Removing The Front Wheel

    FRONT WHEEL Refer to “CHECKING AND TIGHTENING EAM30017 REMOVING THE FRONT WHEEL THE SPOKES” on page 3-23. 1. Use a maintenance stand to raise the front 4. Tighten: wheel off the ground. • Spoke EWA13120 Refer to “CHECKING AND TIGHTENING WARNING THE SPOKES”...

  • Page 97: Installing The Front Wheel

    FRONT WHEEL or numbers facing outward. Tighten the bolts in stages and in a crisscross ECA24420 pattern. NOTICE Install the bearing by pressing its outer race 3. Install: parallel. • Collar “1” • Apply the lithium-soap-based grease on the oil seal lip.
  • Page 98 FRONT WHEEL 3. Tighten: • Front wheel axle nut “1” Front wheel axle nut 105 N·m (10.5 kgf·m, 77 lb·ft) ECA24430 NOTICE Before tightening the front wheel axle nut, push down hard on the handlebar(s) several times and check if the front fork rebounds smoothly.
  • Page 99 REAR WHEEL EAM20096 REAR WHEEL Removing the rear wheel 12 N ・ m (1.2 kgf ・ m, 8.9 lb ・ ft) 125 N ・ m (12.5 kgf ・ m, 92 lb ・ ft) 19 N ・ m (1.9 kgf ・ m, 14 lb ・ ft) 42 N ・...

  • Page 100: Rear Wheel

    REAR WHEEL Refer to “CHECKING THE TIRES” on page EAM30022 REMOVING THE REAR WHEEL 3-23 and “CHECKING THE WHEELS” on 1. Use a maintenance stand to raise the rear page 3-23. wheel off the ground. 3. Check: EWA13120 • Spoke WARNING Refer to “CHECKING AND TIGHTENING Securely support the vehicle so that there is...

  • Page 101: Assembling The Rear Wheel

    REAR WHEEL Tighten the self-locking nuts in stages and in a crisscross pattern. EAM30026 ASSEMBLING THE REAR WHEEL 1. Install: • Bearing (right side) “1” • Circlip “2” • Spacer “3” G088898 • Bearing (left side) “4” 2. Install: • Oil seal “5” •...
  • Page 102 REAR WHEEL 2. Install: 5. Adjust: • Drive chain “1” • Drive chain slack “a” Drive chain slack (Maintenance Push the rear wheel “2” forward and install the Stand) drive chain. 48.0–58.0 mm (1.89–2.28 in) Refer to “DRIVE CHAIN SLACK” on page 3-16.

  • Page 103: Front Brake

    FRONT BRAKE EAM20097 FRONT BRAKE Removing the front brake caliper 30 N ・ m (3.0 kgf ・ m, 22 lb ・ ft) 28 N ・ m (2.8 kgf ・ m, 21 lb ・ ft) 6 N ・ m (0.6 kgf ・ m, 4.4 lb ・ ft) 17 N ・...
  • Page 104 FRONT BRAKE Disassembling the front brake caliper 6 N ・ m (0.6 kgf ・ m, 4.4 lb ・ ft) Order Job/Parts to remove Q’ty Remarks Brake caliper piston kit Brake caliper piston seal kit Bleed screw 4-12...
  • Page 105 FRONT BRAKE Removing the front brake master cylinder 1.5 N ・ m (0.15 kgf ・ m, 1.1 lb ・ ft) 6 N ・ m (0.6 kgf ・ m, 4.4 lb ・ ft) 6 N ・ m (0.6 kgf ・ m, 4.4 lb ・ ft) 9 N ・...
  • Page 106 FRONT BRAKE Disassembling the front brake master cylinder Order Job/Parts to remove Q’ty Remarks Brake master cylinder kit 4-14...

  • Page 107: Introduction

    FRONT BRAKE b. Remove the brake caliper. EAM30028 INTRODUCTION c. Hold the dial gauge at a right angle against EWA19210 the brake disc surface. WARNING d. Measure the runout 1.5 mm (0.06 in) If you need to disassemble the disc brake above the brake disc edge.
  • Page 108 FRONT BRAKE d. Remove the pad pin and brake pads “4”. Brake caliper bleed screw 6 N·m (0.6 kgf·m, 4.4 lb·ft) d. Install the brake pads “3” and the pad pin. • Install the brake pads with their projections “a” into the brake caliper recesses “b”.

  • Page 109: Removing The Front Brake Caliper

    FRONT BRAKE 4. Check: • Brake fluid level Refer to “CHECKING THE BRAKE FLUID LEVEL” on page 3-14. 5. Check: • Brake lever operation A softy or spongy feeling  Bleed the brake system. Refer to “BLEEDING THE HYDRAULIC BRAKE SYSTEM” on page 3-15. b.

  • Page 110: Installing The Front Brake Caliper

    FRONT BRAKE cleaning and lubricating. Brake pad pin • Never use solvents on internal brake com- 17 N·m (1.7 kgf·m, 13 lb·ft) ponents as they will cause the piston seals to swell and distort. Refer to “CHECKING THE FRONT BRAKE •...

  • Page 111: Removing The Front Brake Master Cylinder

    FRONT BRAKE Refer to “BLEEDING THE HYDRAULIC 3. Check: • Brake hose BRAKE SYSTEM” on page 3-15. Cracks/damage/wear  Replace. 6. Check: • Brake fluid level EAM30038 The minimum level mark or below  Add. ASSEMBLING THE FRONT BRAKE MASTER Refer to “CHECKING THE BRAKE FLUID CYLINDER LEVEL”...

  • Page 112: Installing The Front Brake Master Cylinder

    FRONT BRAKE • First, tighten the upper bolt, then the lower bolt. Install the spring with a smaller inside diameter to the brake master cylinder piston. 2. Install: • Copper washer “1” • Brake hose “2” 4. Install: • Union bolt “3” •...
  • Page 113 FRONT BRAKE EWA13090 WARNING • Use only the designated brake fluid. Other brake fluids may cause the rubber seals to deteriorate, causing leakage and poor brake performance. • Refill with the same type of brake fluid that is already in the system. Mixing brake fluids may result in a harmful chemical reaction, leading to poor brake performance.

  • Page 114: Rear Brake

    REAR BRAKE EAM20098 REAR BRAKE Removing the rear brake caliper 2.5 N ・ m (0.25 kgf ・ m, 1.8 lb ・ ft) 10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft) 17 N ・ m (1.7 kgf ・ m, 13 lb ・ ft) 30 N ・...
  • Page 115 REAR BRAKE Disassembling the rear brake caliper 6 N ・ m (0.6 kgf ・ m, 4.4 lb ・ ft) Order Job/Parts to remove Q’ty Remarks Brake caliper piston kit Brake caliper piston seal kit Bleed screw 4-23...
  • Page 116 REAR BRAKE Removing the rear brake master cylinder 1.5 N ・ m (0.15 kgf ・ m, 1.1 lb ・ ft) 10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft) 30 N ・ m (3.0 kgf ・ m, 22 lb ・ ft) Order Job/Parts to remove Q’ty...
  • Page 117 REAR BRAKE Disassembling the rear brake master cylinder Order Job/Parts to remove Q’ty Remarks Brake master cylinder joint Brake master cylinder kit 4-25...

  • Page 118: Introduction

    REAR BRAKE EAM30040 INTRODUCTION Brake disc runout limit (as mea- sured on wheel) EWA19260 0.15 mm (0.0059 in) WARNING If you need to disassemble the disc brake 4. Replace: components, observe the following precau- • Brake disc tions. Refer “ASSEMBLING REAR •...
  • Page 119 REAR BRAKE Brake caliper bleed screw 6 N·m (0.6 kgf·m, 4.4 lb·ft) d. Install the brake pad “3” and the pad pin “4”. • Install the brake pads with their projections “a” into the brake caliper recesses “b”. • Temporarily tighten the pad pin at this point. 2.

  • Page 120: Removing The Rear Brake Caliper

    REAR BRAKE the brake caliper. EWA13550 WARNING • Cover the brake caliper piston with a rag. Be careful not to get injured when the pis- ton is expelled from the brake caliper. • Never try to pry out the brake caliper pis- ton.

  • Page 121: Assembling The Rear Brake Caliper

    REAR BRAKE 2. Check: • Brake caliper bracket Crack/damage  Replace. EAM30045 ASSEMBLING THE REAR BRAKE CALIPER EWA19280 WARNING • Before installation, clean and lubricate the internal parts. Use new brake fluid for cleaning and lubricating. • Never use solvents on internal brake com- 3.

  • Page 122: Removing The Rear Brake Master Cylinder

    REAR BRAKE 6. Check: • Brake master cylinder reservoir diaphragm • Brake fluid level holder The minimum level mark or below  Add. • Brake master cylinder reservoir diaphragm Crack/damage  Replace. Refer to “CHECKING THE BRAKE FLUID LEVEL” on page 3-14. 4.

  • Page 123: Installing The Rear Brake Master Cylinder

    REAR BRAKE 3. Install: EWA13531 WARNING • Spring “1” Proper brake hose routing is essential to in- (to the brake master cylinder piston “2”) sure safe vehicle operation. Install the spring with a smaller inside diameter ECA24500 to the brake master cylinder piston. NOTICE Make sure that the pipe portion of the brake hose touches the projection “a”...
  • Page 124 REAR BRAKE LEVEL” on page 3-14. 5. Check: • Brake pedal operation A softy or spongy feeling  Bleed the brake system. Refer to “BLEEDING THE HYDRAULIC BRAKE SYSTEM” on page 3-15. 4-32...
  • Page 125 HANDLEBAR EAM20099 HANDLEBAR Removing the handlebar Order Job/Parts to remove Q’ty Remarks Refer to “GENERAL CHASSIS” on page Number plate 4-1. Brake master cylinder Throttle cable cap Throttle cable Right grip Cap cover Collar Clutch cable Clutch lever holder Engine stop switch Left grip Upper handlebar holder Handlebar...

  • Page 126: Handlebar

    HANDLEBAR EAM30052 EWA13120 REMOVING THE HANDLEBAR WARNING 1. Stand the vehicle upright on a level surface. Securely support the vehicle so that there is EWA13120 no danger of it falling over. WARNING 2. Install: Securely support the vehicle so that there is •...
  • Page 127 HANDLEBAR in place on both sides. Lower handlebar holder nut • Install the handlebar so that the projection “c” 40 N·m (4.0 kgf·m, 30 lb·ft) of the upper handlebar holders is positioned at the mark on the handlebar as shown. •...
  • Page 128 HANDLEBAR • Pass the engine stop switch lead in the middle of the clutch lever holder. 0 mm (0 in) 0 mm (0 in) 10.Install: • Grip cap (upper) “1” • Grip cap (lower) “2” 7. Install: • Grip cap bolt “3” •...
  • Page 129 HANDLEBAR Throttle cable cap screw 0.5 N·m (0.05 kgf·m, 0.37 lb·ft) 12.Install: • Throttle cable “1” (to the tube guide “2”) 15.Adjust: Apply the lithium-soap-based grease on the • Throttle grip free play throttle cable end and tube guide cable winding Refer to “CHECKING THE THROTTLE portion.
  • Page 130 HANDLEBAR 18.Install: • Grip cap bolt “1” Grip cap bolt 3.8 N·m (0.38 kgf·m, 2.8 lb·ft) EWA21080 WARNING After tightening the bolts, check that the throttle grip “2” moves smoothly. If it does not, retighten the bolts for adjustment. 4-38...
  • Page 131 FRONT FORK EAM20100 FRONT FORK Removing the front fork legs Order Job/Parts to remove Q’ty Remarks Use a maintenance stand to raise the front wheel off the ground. Front wheel Refer to “FRONT WHEEL” on page 4-3. Front brake caliper Refer to “FRONT BRAKE”...
  • Page 132 FRONT FORK Disassembling the front fork leg Order Job/Parts to remove Q’ty Remarks Adjuster Fork spring Damper adjusting rod Dust seal Stopper ring Inner tube Outer tube Piston metal Protector guide Slide metal Washer Oil seal Base valve Damper assembly Upper spring seat 4-40...

  • Page 133: Removing The Front Fork Legs

    FRONT FORK • Hold the locknut and remove the adjuster. EAM30055 REMOVING THE FRONT FORK LEGS 1. Use a maintenance stand to raise the front ECA24520 NOTICE wheel off the ground. Do not remove the locknut as the damper rod EWA13120 may go into the damper assembly and not be WARNING...

  • Page 134: Checking The Front Fork Legs

    FRONT FORK dial gauge reading. EWA13650 WARNING Do not attempt to straighten a bent inner tube as this may dangerously weaken it. 2. Check: • Outer tube Scratches/wear/damage  Replace. 3. Measure: • Fork spring free length “a” 5. Remove: Out of specification ...

  • Page 135: Assembling The Front Fork Legs

    1. Stretch the damper assembly fully. 2. Fill: • Damper assembly Recommended oil Yamaha Suspension Oil S1 Standard oil amount 205 cm³ (6.93 US oz, 7.21 Imp.oz) 6. Check: • Upper spring seat “1”...
  • Page 136 FRONT FORK Standard oil level 145–148 mm (5.71–5.83 in) From top of fully stretched damper assembly. 7. Install: • Base valve “1” (to the damper assembly “2”) First bring the damper rod pressure to a maxi- mum. Then install the base valve while releasing the damper rod pressure.
  • Page 137 FRONT FORK 10.After filling, pump the damper assembly “1” 13.Check: slowly up and down more than 10 times to • Damper assembly smooth movement Tightness/binding/rough spots  Repeat the distribute the fork oil. steps (1) to (12). 11.While protecting the damper assembly “1” with a cloth and compressing fully, allow ex- 14.Install: •...
  • Page 138 FRONT FORK G088922 G088923 15.Install: 18.Install: • Piston metal “1” • Oil seal “1” Install the piston metal onto the slot on inner Using a fork seal driver “2”, press the oil seal in until the stopper ring groove fully appears. tube.
  • Page 139 FRONT FORK 21.Check: 24.Install: • Inner tube smooth movement • Damper assembly “1” Tightness/binding/rough spots  Repeat the (to the inner tube “2”) steps (14) to (20). ECA24560 NOTICE Allow the damper assembly to slide slowly down the inner tube until it contacts the bot- tom of the inner tube.
  • Page 140 30.Fill: • Front fork leg Recommended oil If it is installed with a gap out of specification, Yamaha Suspension Oil S1 correct damping force cannot be obtained. Standard oil amount 305 cm³ (10.3 US oz, 10.8 Imp.oz) Extent of adjustment 280–365 cm³...

  • Page 141: Installing The Front Fork Legs

    FRONT FORK 31.Install: 2. Tighten: • Damper assembly “1” • Damper assembly “1” (to the outer tube) Damper assembly (front fork) 30 N·m (3.0 kgf·m, 22 lb·ft) Temporarily tighten the damper assembly. Use the cap bolt ring wrench “2” to tighten the damper assembly.
  • Page 142 FRONT FORK Upper bracket pinch bolt 21 N·m (2.1 kgf·m, 15 lb·ft) • Lower bracket pinch bolt “2” Lower bracket pinch bolt 21 N·m (2.1 kgf·m, 15 lb·ft) EWA19320 WARNING Tighten the lower bracket to specified 7. Adjust: torque. If torqued too much, it may cause the •...

  • Page 143: Steering Head

    STEERING HEAD EAM20101 STEERING HEAD Removing the lower bracket 38 N ・ m (3.8 kgf ・ m, 28 lb ・ ft) 7 N ・ m (0.7 kgf ・ m, 5.2 lb ・ ft) Order Job/Parts to remove Q’ty Remarks Use a maintenance stand to raise the front wheel off the ground.

  • Page 144: Removing The Lower Bracket

    STEERING HEAD EAM30060 ECA14270 REMOVING THE LOWER BRACKET NOTICE 1. Use a maintenance stand to raise the front If the bearing race is not installed properly, wheel off the ground. the steering head pipe could be damaged. EWA13120 WARNING Always replace the bearing and the bearing race Securely support the vehicle so that there is as a set.
  • Page 145 STEERING HEAD • Upper bearing “1” • Bearing race cover “2” Apply the lithium-soap-based grease on the bearing and bearing race cover lip. 5. Check the steering stem by turning this lock to lock. If there is any binding, remove the steering stem and check the steering bear- ing.
  • Page 146 STEERING HEAD Upper bracket pinch bolt 21 N·m (2.1 kgf·m, 15 lb·ft) • Lower bracket pinch bolt “2” Lower bracket pinch bolt 21 N·m (2.1 kgf·m, 15 lb·ft) EWA19330 WARNING Tighten the lower bracket to specified 8. Install: torque. If torqued too much, it may cause the •...

  • Page 147: Rear Shock Absorber Assembly

    REAR SHOCK ABSORBER ASSEMBLY EAM20102 REAR SHOCK ABSORBER ASSEMBLY Removing the rear shock absorber assembly 2.3 N ・ m (0.23 kgf ・ m, 1.7 lb ・ ft) Order Job/Parts to remove Q’ty Remarks Refer to “GENERAL CHASSIS” on page Seat 4-1.
  • Page 148 REAR SHOCK ABSORBER ASSEMBLY Disassembling the relay arm Order Job/Parts to remove Q’ty Remarks Relay arm Connecting arm Collar Oil seal Washer Bearing 4-56...

  • Page 149: Handling The Rear Shock Absorber

    • To dispose of a damaged or a worn-out rear • Spring shock absorber, take the unit to your Damage/wear  Replace. Yamaha dealer for this disposal procedure. • Spring guide Damage/wear  Replace. • Bearing Damage/wear  Replace.

  • Page 150: Installing The Relay Arm

    REAR SHOCK ABSORBER ASSEMBLY Damage/pitting/scratches  Replace the Installed depth “a” bearings and collars as a set. 0 mm (0 in) 3. Check: • Oil seal Damage/pitting  Replace. EAM30069 INSTALLING THE RELAY ARM 1. Lubricate: • Oil seal • Bearing •...
  • Page 151 REAR SHOCK ABSORBER ASSEMBLY Connecting arm nut (relay arm Install the dust seals with their lips facing inward. side) 80 N·m (8.0 kgf·m, 59 lb·ft) Installed depth “a” 4.25 mm (0.17 in) • Relay arm nut (swingarm side) Relay arm nut (swingarm side) 70 N·m (7.0 kgf·m, 52 lb·ft) •...

  • Page 152: Swingarm

    SWINGARM EAM20103 SWINGARM Removing the swingarm Order Job/Parts to remove Q’ty Remarks Use a maintenance stand to raise the rear wheel off the ground. Brake hose holder Rear brake caliper Refer to “REAR BRAKE” on page 4-22. Brake pedal bolt Drive chain Collar Oil seal...

  • Page 153: Removing The Swingarm

    SWINGARM • Bearing EAM30071 REMOVING THE SWINGARM 4. Check: 1. Use a maintenance stand to raise the rear • Oil seal wheel off the ground. Damage  Replace. EWA13120 • Bearing WARNING • Thrust bearing Securely support the vehicle so that there is •...
  • Page 154 SWINGARM 4. Install: • Rear wheel Refer to “REAR WHEEL” on page 4-7. 5. Adjust: • Drive chain slack Refer to “DRIVE CHAIN SLACK” on page 3-16. Drive chain slack (Maintenance Stand) 48.0–58.0 mm (1.89–2.28 in) 4-62...

  • Page 155: Chain Drive

    CHAIN DRIVE EAM20104 CHAIN DRIVE Removing the drive chain 75 N ・ m (7.5 kgf ・ m, 55 lb ・ ft) 5 N ・ m (0.5 kgf ・ m, 3.7 lb ・ ft) Order Job/Parts to remove Q’ty Remarks Drive sprocket Refer to “ENGINE REMOVAL”...

  • Page 156: Removing The Drive Chain

    CHAIN DRIVE EAM30075 REMOVING THE DRIVE CHAIN 1. Stand the vehicle on a level surface. EWA13120 WARNING Securely support the vehicle so that there is no danger of it falling over. 2. Remove: • Master link clip • Master link “1” G088938 •...

  • Page 157: Checking The Drive Sprocket

    CHAIN DRIVE G088942 G089069 5. Lubricate: • Drive chain EAM30077 CHECKING THE DRIVE SPROCKET 1. Check: • Drive sprocket More than 1/4 tooth wear “a”  Replace the drive sprocket and the rear wheel sprocket as a set. G089070 Bent tooth  Replace the drive sprocket and 2.
  • Page 158 CHAIN DRIVE 4-66...

  • Page 159: Engine

    ENGINE ENGINE REMOVAL ..................5-1 REMOVING THE ENGINE .................5-4 INSTALLING THE ENGINE ................5-4 INSTALLING THE EXHAUST PIPE AND MUFFLER .........5-4 CYLINDER HEAD, CYLINDER AND PISTON ..........5-6 REMOVING THE CYLINDER HEAD ............5-8 REMOVING THE PUSH ROD ..............5-8 REMOVING THE PISTON................5-8 CHECKING THE CYLINDER HEAD ............5-9 CHECKING THE CYLINDER AND PISTON..........5-9 COMBINATION OF PISTON AND CYLINDER ........5-10 CHECKING THE PISTON RING ..............5-11...
  • Page 160 CHECKING THE CLUTCH HOUSING .............5-30 CHECKING THE CLUTCH BOSS ............5-30 CHECKING THE PRESSURE PLATE .............5-31 CHECKING THE PUSH LEVER SHAFT ..........5-31 CHECKING THE PUSH RODS ..............5-31 CHECKING THE PRIMARY DRIVE GEAR ..........5-31 CHECKING THE PRIMARY DRIVEN GEAR..........5-31 INSTALLING THE CLUTCH ..............5-31 SHIFT SHAFT ....................5-35 REMOVING THE SEGMENT ..............5-36 CHECKING THE SHIFT SHAFT ..............5-36...
  • Page 161 ENGINE REMOVAL EAM20105 ENGINE REMOVAL Removing the exhaust pipe 12 N ・ m (1.2 kgf ・ m, 8.9 lb ・ ft) 15 mm (0.59 in) 12 N ・ m (1.2 kgf ・ m, 8.9 lb ・ ft) 10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft) 12 N ・...
  • Page 162 ENGINE REMOVAL Removing the engine 34 N ・ m (3.4 kgf ・ m, 25 lb ・ ft) 64 N ・ m (6.4 kgf ・ m, 47 lb ・ ft) 26 N ・ m (2.6 kgf ・ m, 19 lb ・ ft) 85 N ・...
  • Page 163 ENGINE REMOVAL Removing the engine 34 N ・ m (3.4 kgf ・ m, 25 lb ・ ft) 64 N ・ m (6.4 kgf ・ m, 47 lb ・ ft) 26 N ・ m (2.6 kgf ・ m, 19 lb ・ ft) 85 N ・...

  • Page 164: Engine Removal

    ENGINE REMOVAL • Engine mounting nut (front side) “7” EAM30161 REMOVING THE ENGINE 1. Remove: Engine mounting nut (front side) 64 N·m (6.4 kgf·m, 47 lb·ft) • Pivot shaft “1” • Engine bracket “8” If the pivot shaft is pulled all the way out, the •...
  • Page 165 ENGINE REMOVAL...

  • Page 166: Cylinder Head, Cylinder And Piston

    CYLINDER HEAD, CYLINDER AND PISTON EAM20190 CYLINDER HEAD, CYLINDER AND PISTON Removing the cylinder head and cylinder 20 N ・ m (2.0 kgf ・ m, 15 lb ・ ft) 34 N ・ m (3.4 kgf ・ m, 25 lb ・ ft) 28 N ・...
  • Page 167 CYLINDER HEAD, CYLINDER AND PISTON Disassembling the YPVS system 4.0 N ・ m (0.40 kgf ・ m, 3.0 lb ・ ft) 8 N ・ m (0.8 kgf ・ m, 5.9 lb ・ ft) 5 N ・ m (0.5 kgf ・ m, 3.7 lb ・ ft) 4.0 N ・...

  • Page 168: Removing The Cylinder Head

    CYLINDER HEAD, CYLINDER AND PISTON EAM30086 REMOVING THE CYLINDER HEAD 1. Remove: • Cylinder head nut Loosen each nut 1/2 of a turn at a time. After all of the nuts are fully loosened, remove them. EAM30543 REMOVING THE PUSH ROD 1.

  • Page 169: Checking The Cylinder Head

    CYLINDER HEAD, CYLINDER AND PISTON b. Measure the warpage. c. If the limit is exceeded, resurface the cylin- der head as follows. d. Place a 400–600 grit wet sandpaper on the surface plate and resurface the cylin- der head using a figure-eight sanding pat- tern.

  • Page 170: Combination Of Piston And Cylinder

    CYLINDER HEAD, CYLINDER AND PISTON Diameter 53.957–53.972 mm (2.1243– 2.1249 in) 2. Check: • Piston mark “a” Piston mark “a” Piston size (color) a. 17.5 mm (0.69 in) from the bottom edge of 53.957–53.960 mm A (red) the piston (2.1243–2.1244 in) e.

  • Page 171: Checking The Piston Ring

    CYLINDER HEAD, CYLINDER AND PISTON EAM30548 EAM30549 CHECKING THE PISTON RING CHECKING THE PISTON PIN 1. Measure: 1. Check: • Piston ring side clearance • Piston pin Out of specification  Replace the piston Blue discoloration/grooves  Replace the and piston ring as a set. piston pin, and then check the fuel and en- gine mixing oil.

  • Page 172: Checking The Small End Bearing

    CYLINDER HEAD, CYLINDER AND PISTON the aluminum. Piston-pin-to-piston-pin-bore clearance 0.008–0.023 mm (0.0003–0.0009 Limit 0.065 mm (0.0026 in) EAM30550 CHECKING THE SMALL END BEARING 1. Check: • Small end bearing Signs of heat discoloration  Replace. EAM30551 ASSEMBLING THE POWER VALVE 1.

  • Page 173: Installing The Piston And Cylinder

    CYLINDER HEAD, CYLINDER AND PISTON with its opening portion “b” facing backward. 5 5 5 1 1 1 2 2 2 3 3 3 3. Install: • Thrust plate “1” EAM30554 INSTALLING THE PISTON AND CYLINDER • Thrust plate screw “2” 1.
  • Page 174 CYLINDER HEAD, CYLINDER AND PISTON 5. Install: • Cylinder • Cylinder nut “1” Cylinder nut 30 N·m (3.0 kgf·m, 22 lb·ft) 3. Install: • Piston “1” • Piston pin “2” • Piston pin clip “3” • Apply engine oil the piston pin. •...

  • Page 175: Installing The Cylinder Head

    CYLINDER HEAD, CYLINDER AND PISTON 7. Remove: 3. Install: • Collar • Cylinder head “1” 8. Install: • Copper washer “2” • Gasket (power valve housing) • Cylinder head nut “3” • Power valve housing “1” • Power valve housing bolt “2” Cylinder head nut 28 N·m (2.8 kgf·m, 21 lb·ft) Power valve housing bolt...

  • Page 176: Cdi Magneto

    CDI MAGNETO EAM20191 CDI MAGNETO Removing the CDI magneto 7 N ・ m (0.7 kgf ・ m, 5.2 lb ・ ft) 56 N ・ m (5.6 kgf ・ m, 41 lb ・ ft) 5 N ・ m (0.5 kgf ・ m, 3.7 lb ・ ft) Order Job/Parts to remove Q’ty...

  • Page 177: Removing The Rotor

    CDI MAGNETO Damage  Inspect the crankshaft runout and EAM30562 REMOVING THE ROTOR crankshaft bearing. 1. Remove: If necessary, replace CDI magneto and/or • Rotor nut “1” stator. • Washer “2” While holding the rotor with the rotor holding tool “3”, loosen the rotor nut.
  • Page 178 CDI MAGNETO and rotor. of the hole. • When installing the woodruff key, make sure that its flat surface “a” is in parallel with the Stator coil screw crankshaft center line “b”. 7 N·m (0.7 kgf·m, 5.2 lb·ft) • When installing the rotor, align the keyway “c” of the rotor with the woodruff key.
  • Page 179 CDI MAGNETO 5-19...

  • Page 180: Kickstarter

    KICKSTARTER EAM20112 KICKSTARTER Removing the primary drive gear 10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft) 10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft) 48 N ・ m (4.8 kgf ・ m, 35 lb ・ ft) Order Job/Parts to remove Q’ty...
  • Page 181 KICKSTARTER Removing the kickstarter shaft Order Job/Parts to remove Q’ty Remarks Kick idle gear Kick shaft assembly 5-21...

  • Page 182: Removing The Primary Drive Gear

    KICKSTARTER EAM30570 REMOVING THE PRIMARY DRIVE GEAR 1. Loosen: • Primary drive gear bolt “1” Place an aluminum plate “a” between the teeth of the primary drive gear “2” and driven gear “3”. EAM30104 INSTALLING THE KICK SHAFT ASSEMBLY 1. Install: •...

  • Page 183: Installing The Kick Idle Gear

    KICKSTARTER • Slide the kick shaft assembly into the crank- • Primary drive gear “2” • Primary drive gear bolt “3” case, make sure the clip “2” and kick shaft stopper “a” fit into their home position “b”, “c”. Install the primary drive gear with its depressed side toward you.

  • Page 184: Installing The Kickstarter Lever

    KICKSTARTER 5. Install: • Crankcase cover (right) “1” Mesh the governor gear “2”, and impeller shaft gear “3” with primary drive gear “4”. 2. Install: • Shift pedal “1” • Shift pedal bolt “2” Shift pedal bolt 12 N·m (1.2 kgf·m, 8.9 lb·ft) 6.

  • Page 185: Ypvs Governor

    YPVS GOVERNOR EAM20192 YPVS GOVERNOR Removing the YPVS governor 5 N ・ m (0.5 kgf ・ m, 3.7 lb ・ ft) Order Job/Parts to remove Q’ty Remarks Crankcase cover (right) Refer to “KICKSTARTER” on page 5-20. Governor assembly Dowel pin Retainer Ball Retainer weight...

  • Page 186: Removing The Governor

    YPVS GOVERNOR EAM30566 EAM30569 REMOVING THE GOVERNOR INSTALLING THE GOVERNOR 1. Remove: 1. Install: • Dowel pin “1” • Governor gear “1” • Compression spring “2” • Plate “3” While compressing the spring, remove the dow- • Washer “4” el pin. •...
  • Page 187 YPVS GOVERNOR 3. Install: • Dowel pin “1” • While compressing the spring, install the dowel pin. • Make sure the dowel pin fits into the groove “a” in the retainer. 4. Install: • Governor assembly “1” Align the groove “a” in the governor with the fork “b”...
  • Page 188 CLUTCH EAM20111 CLUTCH Removing the clutch 10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft) 10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft) Order Job/Parts to remove Q’ty Remarks Drain. Transmission oil Refer to “CHANGING THE TRANSMISSION OIL”...
  • Page 189 CLUTCH Removing the clutch boss 80 N ・ m (8.0 kgf ・ m, 59 lb ・ ft) Order Job/Parts to remove Q’ty Remarks Push rod 1 Circlip Washer Bearing Ball Push rod 2 Clutch boss nut Lock washer Clutch boss Thrust washer [D = ø34 mm (1.34 in)] Primary driven gear...

  • Page 190: Clutch

    CLUTCH Out of specification  Replace the clutch EAM30108 REMOVING THE CLUTCH plates as a set. 1. Remove: • Clutch boss nut “1” Thickness gauge 90890-03268 • Lock washer Feeler gauge set • Clutch boss “2” YU-26900-9 • While holding the clutch boss with the clutch holder “3”, loosen the clutch boss nut.

  • Page 191: Checking The Pressure Plate

    CLUTCH 2. Measure: • Push rod 2 bending limit Pitting on the clutch boss splines will cause er- Out of specification  Replace. ratic clutch operation. Push rod bending limit 0.30 mm (0.012 in) EAM30117 CHECKING THE PRIMARY DRIVE GEAR 1.
  • Page 192 CLUTCH 4. Install: • Lock washer “1” • Clutch boss nut “2” Clutch boss nut 80 N·m (8.0 kgf·m, 59 lb·ft) Use the clutch holder “3” to hold the clutch boss. Clutch holder 90890-04199 Universal clutch holder YM-91042 2. Install: •...
  • Page 193 CLUTCH 7. Install: 10.Install: • Bearing “1” • Clutch spring • Washer “2” • Clutch spring bolt • Circlip “3” Clutch spring bolt (to the push rod 1 “4”) 10 N·m (1.0 kgf·m, 7.4 lb·ft) Apply the transmission oil on the bearing, wash- er and push rod 1.
  • Page 194 CLUTCH 5-34...

  • Page 195: Shift Shaft

    SHIFT SHAFT EAM20113 SHIFT SHAFT Removing the shift shaft and stopper lever 30 N ・ m (3.0 kgf ・ m, 22 lb ・ ft) 12 N ・ m (1.2 kgf ・ m, 8.9 lb ・ ft) 10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft) Order Job/Parts to remove Q’ty...

  • Page 196: Removing The Segment

    SHIFT SHAFT EAM30124 REMOVING THE SEGMENT 1. Remove: • Segment bolt “1” • Segment “2” Turn the segment counterclockwise until it stops and loosen the bolt. ECA24670 NOTICE If the segment gets an impact, the stopper le- EAM30127 ver may be damaged. Take care not to give CHECKING THE STOPPER LEVER an impact to it when removing the bolt.
  • Page 197 SHIFT SHAFT 2. Install: 4. Install: • Segment “1” • Shift lever assembly • Segment bolt (to the shift guide) 5. Install: Segment • Shift lever assembly “1” 30 N·m (3.0 kgf·m, 22 lb·ft) • Shift guide “2” • The shift lever assembly is installed at the •...
  • Page 198 SHIFT SHAFT Apply the transmission oil on the roller and shift shaft. 8. Install: • Shift pedal “1” • Shift pedal bolt “2” Shift pedal bolt 12 N·m (1.2 kgf·m, 8.9 lb·ft) Align the upper line “a” of the shift pedal with the center “b”...

  • Page 199: Crankcase

    CRANKCASE EAM20116 CRANKCASE Separating the crankcase 10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft) 14 N ・ m (1.4 kgf ・ m, 10 lb ・ ft) 30 N ・ m (3.0 kgf ・ m, 22 lb ・ ft) 20 N ・...

  • Page 200: Disassembling The Crankcase

    CRANKCASE EAM30147 DISASSEMBLING THE CRANKCASE 1. Remove: • Crankcase (right) “1” (with the flywheel puller “2”) Flywheel puller 90890-01362 Heavy duty puller YU-33270-B • Make appropriate bolts “3” as shown available EAM30150 CHECKING THE CRANKCASE by yourself and attach the tool with them. 1.
  • Page 201 • If you use the tools starting from “90890-”, in- stead of the spacer “5” use two plain washers (Yamaha genuine: 90201-243K3) “6” or the Clean the contacting surface of crankcase ones of a size as shown placed on top of each (left/right) before applying the sealant.
  • Page 202 CRANKCASE 7. Install: • Clamp “1” • Crankcase bolt “2” Crankcase bolt 14 N·m (1.4 kgf·m, 10 lb·ft) Tighten the crankcase bolts in stage, using a crisscross pattern. 5-42...

  • Page 203: Crankshaft

    CRANKSHAFT EAM20193 CRANKSHAFT Removing the crankshaft assembly Order Job/Parts to remove Q’ty Remarks Engine Refer to “ENGINE REMOVAL” on page 5-1. Crankcase Separate. Oil seal Crankshaft Bearing 5-43...

  • Page 204: Removing The Crankshaft

    CRANKSHAFT shaft. EAM30491 REMOVING THE CRANKSHAFT 1. Remove: Crank assembly width 55.90–55.95 mm (2.201–2.203 in) • Crankshaft “1” (with the crankcase separating tool “2”) Crankcase separating tool 90890-01135 Crankcase separator YU-01135-B Make appropriate bolts “3” as shown available by yourself and attach the tool with them. ECA22290 NOTICE Do not use a hammer to drive out the crank-...
  • Page 205 CRANKSHAFT seal lip. 5-45...
  • Page 206 TRANSMISSION EAM20118 TRANSMISSION Removing the transmission, shift drum assembly, and shift forks 10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft) 10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft) Order Job/Parts to remove Q’ty Remarks Engine...

  • Page 207: Transmission

    TRANSMISSION EAM30153 REMOVING THE TRANSMISSION 1. Remove: • Main axle “1” • Drive axle “2” • Tap lightly on the transmission drive axle with a soft hammer to remove. • Remove assembly carefully. Note the position of each part. Pay particular attention to the lo- cation and direction of shift forks.

  • Page 208: Installing The Transmission

    TRANSMISSION • Apply the molybdenum disulfide oil on the in- ner and end surface of the idler gear and on the inner surface of the sliding gear, then install. • Apply the molybdenum disulfide grease on the inner surface of the 4th wheel gear, then install. 3.
  • Page 209 TRANSMISSION 6. Install: • Shift cam “1” • Apply the transmission oil on the shift cam. • Install the shift cam while holding up the 5th wheel gear “2” and keeping the shift fork 1 “3” moved in the direction of the arrow. 4.
  • Page 210 TRANSMISSION 5-50...

  • Page 211: Cooling System

    COOLING SYSTEM COOLING SYSTEM DIAGRAMS ..............6-1 RADIATOR......................6-2 CHECKING THE RADIATOR ..............6-3 INSTALLING THE RADIATOR ..............6-3 WATER PUMP ....................6-5 DISASSEMBLING THE WATER PUMP .............6-6 CHECKING THE WATER PUMP ...............6-6 ASSEMBLING THE WATER PUMP ............6-6...

  • Page 212: Cooling System Diagrams

    COOLING SYSTEM DIAGRAMS EAM20186 COOLING SYSTEM DIAGRAMS 1. Radiator hose 1 2. Radiator (right) 3. Radiator hose 4 4. Water pump 5. Radiator (left)
  • Page 213 RADIATOR EAM20138 RADIATOR Removing the radiator 1.5 N ・ m (0.15 kgf ・ m, 1.1 lb ・ ft) 10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft) 1.5 N ・ m (0.15 kgf ・ m, 1.1 lb ・ ft) 10 N ・...

  • Page 214: Radiator

    RADIATOR EAM30341 CHECKING THE RADIATOR Radiator cap valve opening pres- sure EWA13030 93.3–122.7 kPa (0.93–1.23 WARNING kgf/cm², 13.5–17.8 psi) A hot radiator is under pressure. Therefore, do not remove the radiator cap when the en- No stay  Replace. gine is hot. Scalding hot fluid and steam may be blown out, which could cause serious in- Radiator cap tester jury.
  • Page 215 RADIATOR G089031 4. Activate the tester to apply the test pressure. Test pressure value 122.7 kPa (1.23 kgf/cm², 17.8 psi) ECA24270 NOTICE • Do not apply such a high pressure as ex- ceeds the test pressure. • Make sure that a checkup after the cylinder head gasket is replaced is made after 3 min- utes of warm-up.

  • Page 216: Water Pump

    WATER PUMP EAM20139 WATER PUMP Removing the water pump 10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft) 10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft) Order Job/Parts to remove Q’ty Remarks Crankcase cover (right) Refer to “KICKSTARTER”...

  • Page 217: Disassembling The Water Pump

    WATER PUMP EAM30494 DISASSEMBLING THE WATER PUMP • Remove the oil seal when the coolant level changes frequently more than usual, coolant has discolored, or engine oil has become milky. • Do not use the removed oil seal. 1. Remove: •...
  • Page 218 WATER PUMP • Collar “4” • Circlip “6” Install the impeller shaft gear with the dowel pin fitted in the groove “a” in the same gear. 5. Install: • Dowel pin “1” • Gasket “2” 6. Install: • Water pump housing “1” •...

  • Page 219: Fuel System

    FUEL SYSTEM FUEL TANK ......................7-1 AIR FILTER .......................7-2 CARBURETOR ....................7-3 HANDLING NOTE ..................7-6 CHECKING THE CARBURETOR ..............7-6 CHECKING THE REED VALVE ..............7-7 INSTALLING THE REED VALVE ...............7-7 ASSEMBLING THE CARBURETOR ............7-7 INSTALLING THE CARBURETOR ............7-10 MEASURING AND ADJUSTING THE FUEL LEVEL........7-11...

  • Page 220: Fuel Tank

    FUEL TANK EAM20140 FUEL TANK Removing the fuel tank 7 N ・ m (0.7 kgf ・ m, 5.2 lb ・ ft) 10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft) 7 N ・ m (0.7 kgf ・ m, 5.2 lb ・ ft) 4.0 N ・...

  • Page 221: Air Filter

    AIR FILTER EAM20201 AIR FILTER Removing the air filter element 2.0 N ・ m (0.20 kgf ・ m, 1.5 lb ・ ft) 3.5 N ・ m (0.35 kgf ・ m, 2.6 lb ・ ft) 8 N ・ m (0.8 kgf ・ m, 5.9 lb ・ ft) Order Job/Parts to remove Q’ty...

  • Page 222: Carburetor

    CARBURETOR EAM20194 CARBURETOR Removing the carburetor and reed valve 10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft) 2.3 N ・ m (0.23 kgf ・ m, 1.7 lb ・ ft) 2.3 N ・ m (0.23 kgf ・ m, 1.7 lb ・ ft) Order Job/Parts to remove Q’ty...
  • Page 223 CARBURETOR Disassembling the carburetor Order Job/Parts to remove Q’ty Remarks Mixing chamber top Gasket Throttle valve Ring Throttle valve spring Jet needle holder Collar Spring Jet needle Air vent hose Air vent hose Starter plunger Fuel cut solenoid valve Throttle position sensor Lever comp...
  • Page 224 CARBURETOR Disassembling the carburetor Order Job/Parts to remove Q’ty Remarks Throttle stop screw Pilot air screw Plug Overflow hose Float chamber Float pin Float Needle valve Main jet Pilot jet Power jet...

  • Page 225: Handling Note

    CARBURETOR EAM30580 HANDLING NOTE ECA27120 NOTICE Do not loosen the screw (throttle position sensor) “1” except when changing the throt- tle position sensor due to failure because it will cause a drop in engine performance. 6. Check: • Needle valve “1” •...

  • Page 226: Checking The Reed Valve

    CARBURETOR EAM30577 8. Check: INSTALLING THE REED VALVE • Free movement 1. Install: Stick  Repair or replace. • Gasket • Reed valve assembly “1” Insert the throttle valve “2” into the carburetor body while pulling up the lever “1”, and check for free movement.
  • Page 227 CARBURETOR 2. Install: 5. Install: • Pilot jet “1” • O-ring • Main jet “2” • Solenoid valve (to the carburetor) ECA27130 NOTICE Before installing the solenoid valve, blow air on the solenoid valve and its installing loca- tion on the carburetor in order to remove any foreign particles such as chips etc.
  • Page 228 CARBURETOR • Mixing chamber top “3” • Gasket “4” • Throttle valve spring “5” • Ring “6” • Throttle valve “7” • Jet needle “8” • While compressing the spring, connect the throttle cable. • Align the projection “a” on the ring with the groove “b”...

  • Page 229: Installing The Carburetor

    CARBURETOR 1 1 1 3. Tighten: EAM30578 INSTALLING THE CARBURETOR • Carburetor joint bolt “1” 1. Install: • Carburetor “1” Place the bolt head “a” with its top as shown and secure the clamp in alignment with the horizon- • Install the projection between the carburetor tal line “b”...

  • Page 230: Measuring And Adjusting The Fuel Level

    CARBURETOR EAM30579 MEASURING AND ADJUSTING THE FUEL LEVEL 1. Measure: • Float height “a” Out of specification  Adjust. Float height 6.5 mm (0.26 in) a. Hold the carburetor in an upside down po- sition. b. Measure the distance between the mating surface of the float chamber and top of the float using a vernier calipers.

  • Page 231: Electrical System

    ELECTRICAL SYSTEM WIRING DIAGRAM ...................8-1 COLOR CODE....................8-1 IGNITION SYSTEM...................8-2 TROUBLESHOOTING................8-2 SOLENOID VALVE SYSTEM ................8-3 TROUBLESHOOTING................8-3 THROTTLE POSITION SENSOR SYSTEM .............8-4 TROUBLESHOOTING................8-4 ELECTRICAL COMPONENTS.................8-5 CHECKING THE SWITCHES..............8-6 CHECKING THE IGNITION SPARK GAP ..........8-8 CHECKING THE SPARK PLUG CAP ............8-8 CHECKING THE IGNITION COIL ..............8-8 CHECKING THE PICKUP COIL ..............8-9 CHECKING THE SOURCE COIL ...............8-9 CHECKING THE SOLENOID VALVE OPERATION ........8-10...

  • Page 232: Wiring Diagram

    WIRING DIAGRAM EAM20195 WIRING DIAGRAM G/L B/R W/L B G/W W/R B/W B 1. CDI unit 2. Engine stop switch 3. Ignition coil 4. Throttle position sensor 5. Solenoid valve 6. Joint connector 7. CDI magneto 8. Spark plug EAM30608 COLOR CODE Black Blue...

  • Page 233: Ignition System

    IGNITION SYSTEM EAM20142 IGNITION SYSTEM EAM30278 TROUBLESHOOTING The ignition system fails to operate (no spark or intermittent spark). Before troubleshooting, remove the following part(s): 1. Seat 2. Fuel tank 1. Check the spark plug. Refer to “CHECKING THE SPARK Re-gap or replace the spark plug. NG...

  • Page 234: Solenoid Valve System

    SOLENOID VALVE SYSTEM EAM20196 SOLENOID VALVE SYSTEM EAM30581 TROUBLESHOOTING If the solenoid valve will not operate, use the following inspection steps. Before troubleshooting, remove the following part(s): 1. Seat 2. Fuel tank Use 12 V battery in this inspection. 1. Check each couplers and wire con- Reconnect.

  • Page 235: Throttle Position Sensor System

    THROTTLE POSITION SENSOR SYSTEM EAM20197 THROTTLE POSITION SENSOR SYSTEM EAM30582 TROUBLESHOOTING If the throttle position sensor will not operate, use the following inspection steps. Before troubleshooting, remove the following part(s): 1. Seat 2. Fuel tank 1. Check entire ignition system for Reconnect.

  • Page 236: Electrical Components

    ELECTRICAL COMPONENTS EAM20147 ELECTRICAL COMPONENTS 1. CDI unit 2. Engine stop switch 3. Ignition coil 4. Throttle position sensor 5. Solenoid valve...

  • Page 237: Checking The Switches

    ELECTRICAL COMPONENTS EAM30289 CHECKING THE SWITCHES 1. Engine stop switch...
  • Page 238 ELECTRICAL COMPONENTS Check each switch for continuity with the digital circuit tester. If the continuity reading is incorrect, check the wiring connections and if necessary, replace the switch. ECA14371 NOTICE Never insert the tester probes into the coupler terminal slots. Always insert the probes from the opposite end “a”...

  • Page 239: Checking The Ignition Spark Gap

    ELECTRICAL COMPONENTS EAM30294 CHECKING THE IGNITION SPARK GAP Digital circuit tester (CD732) 90890-03243 1. Check: Model 88 Multimeter with tachom- • Ignition spark gap eter Out of specification  Perform the ignition YU-A1927 system troubleshooting, starting with step (3). Refer to “TROUBLESHOOTING” on page 8-2.

  • Page 240: Checking The Pickup Coil

    ELECTRICAL COMPONENTS a. Connect the digital circuit tester () to the pickup coil coupler as shown. Digital circuit tester (CD732) 90890-03243 Model 88 Multimeter with tachom- eter YU-A1927 • Positive tester probe  White/Red “1” • Negative tester probe  c.

  • Page 241: Checking The Solenoid Valve Operation

    ELECTRICAL COMPONENTS • Positive battery lead  Red “1” • Negative battery lead  Red “2” 1 1 1 b. Measure the source coil resistance (B/R– 3. Check: • Charging coil 2 resistance (G/L–G/W) 3. Check: Out of specification  Replace the CDI mag- •...

  • Page 242: Handling Note

    ELECTRICAL COMPONENTS Out of specification  Replace. EAM30587 HANDLING NOTE • Positive tester probe  ECA27120 Yellow “1” NOTICE • Negative tester probe  Do not loosen the screw (throttle position Black “2” sensor) “1” except when changing the throt- tle position sensor due to failure because it Throttle position sensor coil vari- will cause a drop in engine performance.
  • Page 243 ELECTRICAL COMPONENTS 1 1 1 3. Replace: 7. Insert the thin electric conductors “2” (lead • Throttle position sensor wire) into the throttle position sensor coupler 4. Install: “1”, as shown, and connect the tester to them. • Throttle position sensor “1” •...

  • Page 244: Checking The Throttle Position Sensor Input Voltage

    ELECTRICAL COMPONENTS a a a 11.Stop the engine. 12.Remove: • Carburetor Refer to “CARBURETOR” on page 7-3. 13.Tighten: • Throttle position sensor screw “1” Tighten the throttle position sensor screws using the T20 bit (tamper resistant fastener type) by aligning the marks “a” that were put before re- moval.

  • Page 245: Troubleshooting

    TROUBLESHOOTING TROUBLESHOOTING ..................9-1 GENERAL INFORMATION ................9-1 TROUBLESHOOTING OF ENGINE ............9-1 TROUBLESHOOTING OF CLUTCH ............9-6 TROUBLESHOOTING OF TRANSMISSION ..........9-7 TROUBLESHOOTING OF COOLING SYSTEM ........9-8 TROUBLESHOOTING OF BRAKE ............9-9 TROUBLESHOOTING OF SUSPENSION ..........9-9 TROUBLESHOOTING OF STEERING/HANDLING.........9-11...

  • Page 246: Troubleshooting

    TROUBLESHOOTING EAM20148 TROUBLESHOOTING EAM30309 GENERAL INFORMATION Troubleshooting information provided here does not cover all the trouble symptoms, possible causes, and remedial actions. Some items may not apply depending on the model. Use this information as a guide and quick reference matrix when performing basic troubleshooting. Refer to the each chapter for detailed information on checking, adjustment, and replacement.
  • Page 247 TROUBLESHOOTING Symptom Possible cause Actions Measure the compression pres- — sure. Tighten the spark plugs to the Loose spark plug specified torque. Tighten bolts or nuts on cylinder Loose cylinder head or cylinder head and cylinder to the specified torque. Compression pressure is low Damaged cylinder head gasket Replace the cylinder head gasket.
  • Page 248 TROUBLESHOOTING Symptom Possible cause Actions Damaged or worn needle valve Replace the needle valve. Adjust the fuel level to the proper Incorrect fuel level level. Bent, worn, or damaged starter Replace the starter plunger. plunger Incorrectly adjusted starter cable Adjust the starter cable. Clogged or damaged carburetor Clean, repair, or replace the car- breather hose...
  • Page 249 TROUBLESHOOTING Symptom Possible cause Actions Water or foreign material in fuel, Change fuel. degraded fuel Clogged carburetor air passage Clean the carburetor. Incorrectly adjusted throttle cable Adjust the throttle grip free play. Improperly synchronized carbure- Adjust synchronization of carbure- tors tors.
  • Page 250 TROUBLESHOOTING Symptom Possible cause Actions Check the air induction system. Failed air induction system Repair or replace faulty parts. Clogged vacuum hose Clean the vacuum hose. Cracks and damage in vacuum Replace the vacuum hose. hose — Damaged carburetor joint Replace the carburetor joint.

  • Page 251: Troubleshooting Of Clutch

    TROUBLESHOOTING EAM30510 TROUBLESHOOTING OF CLUTCH Manual clutch Symptom Possible cause Actions Improperly assembled clutch Reassemble the clutch. Improperly adjusted clutch cable Adjust the clutch lever free play. Tighten the clutch spring bolts to Loose clutch spring the specified torque. Replace the clutch springs as a Fatigued clutch spring set.

  • Page 252: Troubleshooting Of Transmission

    TROUBLESHOOTING Symptom Possible cause Actions Replace the primary drive gear or Damaged or worn primary driven crankshaft, and the clutch housing gear as a set. Tighten the clutch boss nut to the Loose clutch boss nut specified torque. Clutch noise Fatigued clutch damper Replace the clutch housing.

  • Page 253: Troubleshooting Of Cooling System

    TROUBLESHOOTING EAM30512 TROUBLESHOOTING OF COOLING SYSTEM Symptom Possible cause Actions Carbon buildup in piston head and Clean the piston head and com- combustion chamber bustion chamber. Clogged engine cooling water Check and clean the engine cool- passages ing water passages. Damaged or leaking radiator Replace the radiator.

  • Page 254: Troubleshooting Of Brake

    TROUBLESHOOTING EAM30513 TROUBLESHOOTING OF BRAKE Symptom Possible cause Actions Worn brake pad Replace the brake pads as a set. Worn or deflected brake disc Replace the brake disc. Air in hydraulic brake system Bleed the hydraulic brake system. Check the hydraulic brake system Brake fluid leakage and repair or replace faulty parts as necessary.
  • Page 255 TROUBLESHOOTING Symptom Possible cause Actions Fatigued or broken fork spring Replace the fork spring. Incorrect oil viscosity (low) Change to recommended fork oil. Incorrect oil level (low) Adjust to the specified oil level. Improperly adjusted spring pre- Adjust the spring preload. Front fork is soft load (soft) Improperly adjusted rebound...

  • Page 256: Troubleshooting Of Steering/Handling

    TROUBLESHOOTING Symptom Possible cause Actions Oil leaking from rear shock Replace the rear shock absorber. absorber Gas leaking from rear shock Replace the rear shock absorber. absorber Fatigued or damaged rear shock Replace the rear shock absorber. absorber spring Rear suspension is soft Improperly adjusted rear shock Adjust the spring preload.
  • Page 257 TROUBLESHOOTING Symptom Possible cause Actions Tighten the spoke and adjust the Loose spoke runout. Damaged or worn wheel bearing Replace the wheel bearing. Worn, deformed, or incorrect tire Replace the tire. Tighten the wheel axle nut to the Loose wheel axle nut Rear wheel vibration specified torque.
  • Page 258 TROUBLESHOOTING 9-13...

  • Page 259: Tuning

    TUNING ENGINE......................10-1 CARBURETOR SETTING ................10-1 ATMOSPHERIC CONDITIONS AND CARBURETOR SETTINGS ..10-1 TEST RUN ....................10-1 EFFECTS OF THE SETTING PARTS ON THE THROTTLE VALVE OPENING ....................10-2 MAIN JET ADJUSTMENT ................10-2 ADJUSTING THE POWER JET ...............10-2 PILOT AIR SCREW ADJUSTMENT ............10-2 PILOT JET ADJUSTMENT ...............10-3 JET NEEDLE ADJUSTMENT ..............10-3 JET NEEDLE GROOVE POSITION ADJUSTMENT ........10-4 RELATIONSHIP WITH THROTTLE OPENING........10-4...

  • Page 260: Engine

    ENGINE • Lower atmospheric pressure (at a high alti- EAM20198 ENGINE tude) reduces the density of the air. EAM30590 EAM30592 CARBURETOR SETTING TEST RUN • The role of fuel is to cool the engine, and in the After warming up the engine equipped with the case of a 2-stroke engine, to lubricate the en- standard type carburetor(s) and spark plug(s), gine in addition to power generation.

  • Page 261: Effects Of The Setting Parts On The Throttle Valve Opening

    ENGINE EAM30593 EFFECTS OF THE SETTING PARTS ON THE THROTTLE VALVE OPENING EAM30604 ADJUSTING THE POWER JET The richness of air-fuel mixture under 8500 r/min to the extent of 1/2 to full opened throttle can be set by changing the power jet “1”. A larger size jet results in a richer mixture, and a smaller size in a leaner mixture.

  • Page 262: Pilot Jet Adjustment

    ENGINE EAM30596 PILOT JET ADJUSTMENT The richness of air-fuel mixture with the throttle fully closed to 1/2 open can be set by turning the pilot jet “1”. It is changed when adjustment can- NYDD not be made by the pilot air screw alone. NYDE A larger size jet results in a richer mixture at low NYDF...

  • Page 263: Jet Needle Groove Position Adjustment

    ENGINE system is controlled by the main jet and then, it is further regulated by the area between the main nozzle and the jet needle. On the relation- ship between the fuel flow and the throttle open- NYDF ing, the fuel flow relates to the jet needle straight portion diameter around 1/8 to 1/4 throttle open- ing, whereas around 1/4 to 1/1 throttle opening it relates to the taper starting position and to the...

  • Page 264: Carburetor Setting Parts

    ENGINE EAM30599 Part name Size Part number CARBURETOR SETTING PARTS Jet needle Rich NYFD B4X-14916-FD Part name Size Part number NYCD B4X-14916-CD Main jet Rich #175 4MX-14943-42 NYDD B4X-14916-DD #172 4MX-14943-92 NYED B4X-14916-ED #170 4MX-14943-41 NYFE B4X-14916-FE #168 4MX-14943-91 NYCE B4X-14916-CE #165 4MX-14943-40...

  • Page 265: Road Condition And Examples Of Carburetor Setting

    ENGINE EAM30601 ROAD CONDITION AND EXAMPLES OF CARBURETOR SETTING General condition Sandy condition 15–25 C 15–25 C Under 10 C Over 25 C Under 10 C Over 25 C (59–77 F) (59–77 F) (50 F) (77 F) (50 F) (77 F) (Spring, (Spring, (Winter)
  • Page 266 ENGINE Symptom Setting Checking Lean mixture Lower jet needle clip position. (1 groove down) Rich mixture Raise jet needle clip position. (1 groove up) • 1/4–3/4 throttle Lower jet needle clip position. (1 Leaner *Hard breathing groove down) Lack of speed (Standard) 1.

  • Page 267: Change Of The Heat Range Of Spark Plugs

    ENGINE EAM30603 CHANGE OF THE HEAT RANGE OF SPARK PLUGS Judging from the discoloration of spark plugs, if they are found improper, it can be corrected by the following two methods; changing carburetor settings and changing the heat range of spark plug.

  • Page 268: Chassis

    CHASSIS EAM20119 Part name Type Part number CHASSIS Rear wheel 17D-25447-50 EAM30168 sprocket “2” SELECTION OF THE SECONDARY 17D-25448-50 REDUCTION RATIO (SPROCKET) (STD) B2W-25449-00 Secondary reduction ratio = Number of B2W-25450-00 rear wheel sprocket teeth/Number of B2W-25451-00 drive sprocket teeth 17D-25452-50 Secondary reduction ratio 3.769 (49/13)

  • Page 269: Front Fork Setting

    (in position etc.) when Recommended oil setting the front fork. Yamaha Suspension Oil S1 1. Use of soft spring Standard oil amount • Change the rebound damping force.

  • Page 270: Front Fork Setting Parts

    CHASSIS Generally a stiff spring gives a stiff riding feeling. Rebound damping tends to become weaker, re- sulting in lack of a sense of contact with the road surface or in a vibrating handlebar. EAM30174 FRONT FORK SETTING PARTS • Front fork spring STD spring rate (N/mm) 2.

  • Page 271: Setting Of Spring After Replacement

    CHASSIS [Equal-pitch steel spring] EAM30177 SETTING OF SPRING AFTER STD spring rate REPLACEMENT (N/mm) After replacement, be sure to adjust the spring to the set length [sunken length 90–100 mm (3.5– Spring I.D. Type rate Part number 3.9 in)] and set it. mark/Q’ty (N/mm) 1.
  • Page 272 CHASSIS • The unequal-pitch spring is softer in initial char- acteristic than the equal-pitch spring and is dif- ficult to bottom out under full compression. • The I.D. mark “a” is marked at the end of the spring. • Spring specification varies according to the color and quantity of I.D.

  • Page 273: Suspension Setting (Front Fork)

    CHASSIS EAM30179 SUSPENSION SETTING (FRONT FORK) • If any of the following symptoms is experienced with the standard position as the base, make resetting by reference to the adjustment procedure given in the same chart. • Before any change, set the rear shock absorber sunken length to the standard figure 90–100 mm (3.5–3.9 in).

  • Page 274: Suspension Setting (Rear Shock Absorber)

    CHASSIS Section Symptom Check Adjust Large Medium Small Jump Compression Turn adjuster clockwise (about 2 damping force clicks) to increase damping. Turn adjuster counterclockwise Rebound damp- (about 2 clicks) to decrease ing force damping. Low front, tend-   ing to lower front Set sunken length for 95–100 posture Balance with rear...
  • Page 275 CHASSIS Section Symptom Check Adjust Large Medium Small Jump Turn adjuster counterclockwise Rebound damp- (about 2 clicks) to decrease Heavy and drag- ing force   damping. ging Spring Replace with soft spring. Turn adjuster counterclockwise Rebound damp- (about 2 clicks) to decrease ing force damping.
  • Page 276 CHASSIS 10-17...
  • Page 277 EAM20160 Genuine Yamaha Parts text Genuine Yamaha Parts – Genuine Yamaha replacement parts are the exact same parts as the ones originally equipped on your vehicle, providing you with the performance and durability you have come to expect. Why settle for aftermarket parts that may not provide full confidence and satisfaction? Genuine Yamaha Accessories –...

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