Manuale d’uso / di manutenzione del prodotto WR250FM del fabbricante Yamaha
Vai alla pagina of 343
LIT-11626-16-48 WR250FR 5UM-28199-10 OWNER’S SERVICE MANUAL.
.
WR250FR OWNER’S SERVICE MANUAL ©2002 by Yamaha Motor Corporation, U.S.A. 1st Edition, November 2002 All rights reserved. Any reprinting or unauthorized use without the written permission of Yamaha Motor Corporation U.S.A. is expressly prohibited. Printed in Japan P/N.
EC020000 INTRODUCTION Congratulations on your purchase of a Yamaha WR series. This model is the culmina- tion of Yamaha’s vast experience in the pro- duction of pacesetting racing machines. It represents the highest grade of craf tsmanship and reliability that have made Yamaha a leader.
.
IMPORTANT NOTICE THIS MACHINE IS DESIGNED STRICTLY FOR COMPETITION USE, ONLY ON A CLOSED COURSE. It is illegal for this machine to be operated on any public street, road, or highway. Off-road use on public lan ds may also be illegal. Please check local regula- tions before riding.
6. GASOLINE CAN CAUSE INJURY. If you should swallow some gasoline, inhale excess gasoline va pors, or allow any gasoline to get into your eyes, contact a doctor immediatel y. If any gasoline spills onto your skin or clothing, immediately wash skin areas with soap and wate r, and change your clothes.
EC050000 TO THE NEW OWNER This manual will provide you with a good basic understanding of features, operation, and basic maintenance and inspe ction items of this machine. Please read this ma nual carefully and completely before operating your new machine.
EC080000 HOW TO USE THIS MANUAL EC081000 PARTICULARLY IMPORTANT INFORMATION The Safety Alert Symbol means ATTENTION! BECOME ALERT! YOUR SAFETY IS INVOLVED! Failure to follow WARNING instructions could result in severe injury or death to the machine operator, a bystander, or a person inspecting or repairing the machine.
EC083000 MANUAL FORMAT All of the procedures in this manual are organized in a sequential, step-by-step fo rmat. The informa- tion has been complied to provide the mechanic with an easy to read, handy reference th at contains comprehensive explanations of all disassembly, repair, assembly, and inspect ion operations.
ILLUSTRATED SYMBOLS (Refer to the illustration) Illustrated symbols 1 to 7 are designed as thumb tabs to indicate the chapter ’ s number and content.
MEMO.
EC090000 INDEX GENERAL INFORMATION 1 SPECIFICATIONS SPEC 2 REGULAR INSPECTION AND ADJUSTMENTS 3 ENGINE ENG 4 CHASSIS CHAS 5 ELECTRICAL ELEC 6 TUNING TUN 7 GEN INFO INSP ADJ – +.
EC0A0000 CONTENTS CHAPTER 1 GENERAL INFORMATION DESCRIPTION .......................................... 1-1 MACHINE IDENTIFICATION .................... 1-2 IMPORTANT INFORMATION ................... 1-3 CHECKING OF CONNECTION ................ 1-6 SPECIAL TOOLS .
CHAPTER 4 ENGINE SEAT, FUEL TANK AND SIDE COVERS ............................... ........... 4-1 EXHAUST PIPE AND SILENCER ............ 4-3 RADIATOR ............................................... . 4-5 CARBURETOR .....................................
CHAPTER 6 ELECTRICAL ELECTRICAL COMPONENTS AND WIRING DIAGRAM ................................... 6-1 MAP-CONTROLLED CDI UNIT ................ 6-2 IGNITION SYSTEM ... ................................ 6-3 ELECTRIC STARTING SYSTEM .............. 6-8 CHARGING SYSTEM .
GEN INFO 1 - 1 DESCRIPTION EC100000 GENERAL INFORMATION EC110000 DESCRIPTION 1 Clutch lever 2 Hot starter lever 3 Engine stop switch 4 Trip meter 5 Main switch 6 Light switch 7 Start switch 8 Front br.
1 - 2 GEN INFO MACHINE IDENTIFICATION EC120001 MACHINE IDENTIFICATION There are two significant reasons fo r knowing the serial number of your machine: 1. When ordering parts, you can give the number to your Yamaha dealer for positive identification of the model you own.
1 - 3 GEN INFO IMPORTANT INFORMATION EC130000 IMPORTANT INFORMATION EC131010 PREPARATION FOR REMOVAL AND DISASSEMBLY 1. Remove all dirt, mud, dust, and foreign material before removal and disassembly. When washing the machine with high pre s- sured water, cover the parts follows.
1 - 4 GEN INFO IMPORTANT INFORMATION EC132000 ALL REPLACEMENT PARTS 1. We recommend to use Yamaha genuine parts for all replacements. Use oil an d/or grease recommended by Yamaha for assembly and adjustment. EC133000 GASKETS, OIL SEALS AND O-RINGS 1. All gaskets, oil seals, and O-rings should be replaced when an engine is overhauled.
1 - 5 GEN INFO IMPORTANT INFORMATION EC136000 CIRCLIPS 1. All circlips should be inspected carefully before reassembly. Always replace piston pin clips after one use. Replace distorted circlips. When installing a circlip 1 , make sure that the sharp-edged corn er 2 is posi- tioned opposite to the thrust 3 it rece ives.
1 - 6 GEN INFO CHECKING OF CONNECTION EC1C0001 CHECKING OF CONNECTION Dealing with stains, rust, moisture, etc. on the connector. 1. Disconnect: • Connector 2. Dry each terminal with an air blower. 3. Connect and disconnect the connector two or three times.
GEN INFO 1 - 7 SPECIAL TOOLS SPECIAL TOOLS The proper special tools are ne cessary for complete and accu rate tune-up and assembly. Using the correct special tool will help prevent damage caused b y the use of improper tools or improvised techniques.
GEN INFO 1 - 8 SPECIAL TOOLS YM-01442, 90890-01442 Fork seal driver This tool is used when install the fork oil seal. YU-3112-C, 90890-03112 Pocket tester Use this tool to inspect the coil resistance, output voltage and amperage. YU-8036-B 90890-03113 Inductive tachometer Engine tachometer This tool is needed for observing engine rpm.
GEN INFO 1 - 9 SPECIAL TOOLS YM-04141, 90890-04141 Rotor puller This tool is used to remove the flywheel magneto. YM-34487 90890-06754 Dynamic spark tester Ignition checker This instrument is necessary for checking the ignition system components. ACC-QUICK-GS-KT 90890-85505 Quick ga sket YAMAHA Bond No.
1 - 10 GEN INFO CONTROL FUNCTIONS EC150000 CONTROL FUNCTIONS MAIN SWITCH Functions of the respective switch positions are as follows: ON: The engine can be started only at this position.
1 - 11 GEN INFO CONTROL FUNCTIONS EC152000 CLUTCH LEVER The clutch lever 1 is located on the left han- dlebar; it disengage s or engages the clutch. Pull the clutch lever to the handlebar to disen- gage the clutch, and release th e lever to engage the clutch.
1 - 12 GEN INFO CONTROL FUNCTIONS EC157000 REAR BRAKE PEDAL The rear brake pedal 1 is located on the right side of the machine. Press down on the brake pedal to activate the rear brake . FUEL COCK The fuel cock supplies fuel from the tank to carburetor and also filters the fue l.
1 - 13 GEN INFO LIGHT SWITCH The light switch 1 is located on the h andlebar. EC15F000 VALVE JOINT This valve joint 1 prevents fuel from flowing out and is installed to the fuel tank breather hose. CAUTION: In this installation, make sure the arrow faces the fuel tank and also downward.
1 - 14 GEN INFO FUEL Always use the recommended fuel as stated below. Also, be sure to use new gasoline the day of a race. CAUTION: Use only unleaded gasoline. The use of leaded gasoline will cause s evere damage to the engine internal parts such a s valves, piston rings, and exhaust system , etc.
1 - 15 GEN INFO STARTING AND BREAK-IN STARTING AND BREAK-IN W ARNING Never start or run the e ngine in a closed area. The exhaust fumes are poisonous; they can cause loss o f consciousness and death in a very short time. Always operate the machine in a well-ventilated area.
1 - 16 GEN INFO STARTING AND BREAK-IN N OTE: If the engine fails to start by pushin g the start switch, release the switch, wait a few seconds, and then try again. Each starting attempt should be as short as possible to preserve the battery. Do not cra nk the engine more t han 10 seconds on any one attempt.
1 - 17 GEN INFO STARTING AND BREAK-IN STARTING A WARM ENGINE Do not operate the cold starter kno b and throt- tle. Pull the hot starter lever 1 an d start the engine by pushing the start switch or by kick- ing the kickstarter crank forcefully with a firm stroke.
1 - 18 GEN INFO BREAK-IN PROCEDURES 1. Before starting the engine, fill the fuel tank with the fuel. 2. Perform the pre-operat ion checks on the machine. 3. Start and warm up the engine. Check the idle speed, and check the ope ration of the controls and the engine stop swit ch.
GEN INFO 1 - 19 TORQUE-CHECK POINTS TORQUE-CHECK POINTS Frame construct ion Combined seat a nd fuel tank Exhaust system Engine mountin g Steering Steering stem t o handlebar Suspension Front Steering .
1 - 20 GEN INFO CLEANING AND STORAGE EC1B0000 CLEANING AND STORAGE EC1B1000 CLEANING Frequent cleaning of your machine will enhance its appearance, maintain good overall performance, and extend the life of man y com- ponents. 1. Before washing the machine, block off the end of the exhaust pipe to pre vent water from entering.
1 - 21 GEN INFO CLEANING AND STORAGE EC1B2001 STORAGE If your machine is to be st ored for 60 days or more, some preventive measures must be taken to avoid deterioration. After cleaning the machine thoroughly, prepare it for storage as follows: 1. Drain the fuel tank, fuel lines, and the car- buretor float bowl.
SPEC 2 - 1 GENERAL SPECIFICATIONS EC200000 SPECIFICATIONS EC211000 GENERAL SPECIFICATIONS Model name: WR250FR (USA) WR250F (EUROPE) WR250F(R) (CDN, AUS, NZ, ZA) Model code number: 5UM1 (USA) 5UM2 (EUROPE) 5UM4 (CDN, AUS, NZ, ZA) Dimensions: Overall length 2,165 mm (85.
SPEC 2 - 2 GENERAL SPECIFICATIONS Oil capacity: Engine oil Periodic oil change 1.2 L (1.06 Imp qt, 1.27 US q t) With oil filter replacement 1.3 L (1.14 Imp qt, 1.37 US q t) Total amount 1.4 L (1.23 Imp qt, 1.48 US qt) Coolant capacity (including all routes): 1.
SPEC 2 - 3 GENERAL SPECIFICATIONS Brake: Front brake type Single disc brake Operation Right hand operation Rear brake type Single disc brake Operation Right foot operation Suspension: Front suspension.
SPEC 2 - 4 MAINTENANCE SPECIFICATIONS MAINTENANCE SPECIFICATIONS ENGINE Item Standard Limit Cylinder head: Warp limit ---- 0.05 mm (0.002 in) Cylinder: Bore size 77.00 ~ 77.01 mm (3.0315 ~ 3.0319 in) ---- Out of round limit ---- 0.05 mm (0.002 in) Camshaft: Drive method Chain drive (Left) ---- Camshaft cap inside diamete r 22.
SPEC 2 - 5 MAINTENANCE SPECIFICATIONS Timing chain: Timing chain type/No. of links 92RH2010-114M/114 ---- Timing chain adjustment method Automatic ---- Valve, valve seat, valve guide: Valve clearance (cold) IN 0.10 ~ 0.15 mm (0.0039 ~ 0.0059 in) ---- EX 0.
SPEC 2 - 6 MAINTENANCE SPECIFICATIONS Stem runout limit ---- 0.01 mm (0.0004 in) Valve seat width IN 0.9 ~ 1.1 mm (0.0354 ~ 0.0433 in) 1.6 mm (0.0630 in) EX 0.9 ~ 1.1 mm (0.0354 ~ 0.0433 in) 1.6 mm (0.0630 in) Valve spring: Free length IN 37.81 mm (1.
SPEC 2 - 7 MAINTENANCE SPECIFICATIONS Piston pin bore inside diameter 16.002 ~ 16.013 mm (0.6300 ~ 0.6304 in) 16.043 mm (0.6316 in) Piston pin outside diameter 15.991 ~ 16.000 mm (0.6296 ~ 0.6299 in) 15.971 mm (0.6288 in) Piston rings: Top ring: Type Barrel ---- Dimensions (B × T) 0.
SPEC 2 - 8 MAINTENANCE SPECIFICATIONS Clutch: Friction plate thickness 2.9 ~ 3.1 mm (0.114 ~ 0.122 in) 2.7 mm (0.106 in) Quantity 9 ---- Clutch plate thickness 1.1 ~ 1.3 mm (0.043 ~ 0.051 in) ---- Quantity 8 ---- Warp limit ---- 0.1 mm (0.004 in) Clutch spring free length 37.
SPEC 2 - 9 MAINTENANCE SPECIFICATIONS Lubrication system: Oil filter type Paper type ---- Oil pump type Trochoid type ---- Tip clearance 0.12 mm or less (0.0047 in or less) 0.20 mm (0.008 in) Side clearance 0.09 ~ 0.17 mm (0.0035 ~ 0.0067 in) 0.24 mm (0.
SPEC 2 - 10 MAINTENANCE SPECIFICATIONS Part to be tightened Thread size Q ’ ty Tightening torque Nm m · kg ft · lb Spark plug M10S × 1.0 1 13 1.3 9.4 Camshaft cap M 6 × 1.0 1 0 10 1.0 7.2 Cylinder head blind plug screw M12 × 1.0 1 37 3.7 27 Cylinder head (stud bolt) M6 × 1.
SPEC 2 - 11 MAINTENANCE SPECIFICATIONS N OTE: - marked portion shall be checked for torque tightening after break-in o r before each race. Silencer M8 × 1.25 2 35 3.5 25 Silencer clamp M8 × 1.25 1 19 1.9 13 Spark arrester (for USA) M6 × 1.0 3 10 1.
SPEC 2 - 12 MAINTENANCE SPECIFICATIONS CHASSIS Item Standard Limit Steering system: Steering bearing type Taper roller bearing ---- Front suspension: USA, CDN EUROPE AUS, NZ, ZA Front fork travel 300 mm (11.8 in) ←← Fork spring free length 460 mm (18.
SPEC 2 - 13 MAINTENANCE SPECIFICATIONS Wheel: USA, CDN, ZA EUROPE, AUS, NZ Front wheel type Spoke wheel ← ---- Rear wheel type Spoke wheel ← ---- Front rim size/material 21 × 1.60/Aluminum ← ---- Rear rim size/material 18 × 1.85/Aluminum 18 × 2.
SPEC 2 - 14 MAINTENANCE SPECIFICATIONS N OTE: 1. First, tighten the steering nut approximately 38 Nm (3.8 m • kg, 27 ft • lb) by using the steering nut wrench, then loosen the steering nut one tu rn. 2. Retighten the steering nut 7 Nm (0.7 m • kg, 5.
SPEC 2 - 15 MAINTENANCE SPECIFICATIONS Part to be tightened Thread size Q ’ ty Tightening torque Nm m · kg ft · lb Nipple (spoke) — 72 3 0.3 2.2 Rear wheel sprocket M8 × 1.25 6 50 5.0 36 Rear brake disc cover M6 × 1.0 2 7 0.7 5.1 Rear brake caliper protector M6 × 1.
SPEC 2 - 16 MAINTENANCE SPECIFICATIONS N OTE: - marked portion shall be checked for torque tightening after break-in o r before each race. Headlight (left and right) M6 × 1.0 2 10 1.0 7.2 Headlight (lower) M6 × 1.0 1 7 0.7 5.1 Taillight M6 × 1.0 3 4 0.
SPEC 2 - 17 MAINTENANCE SPECIFICATIONS EC212300 ELECTRICAL Item Standard Limit Ignition system: Advancer type Electrical ---- CDI: Pickup coil resistance (color) 248 ~ 372 Ω at 20 ° C (68 ° F) (Wh.
SPEC 2 - 18 MAINTENANCE SPECIFICATIONS Starter relay: Model/manufacturer 2768090-A/JIDECO ---- Amperage rating 180 A ---- Coil winding resistance 4.2 ~ 4.6 Ω at 20 °C (68 °F) ---- Starting circuit cut-off relay: Model/manufacturer ACM33221 M06/MATSUSHITA ---- Coil winding resistance 75.
SPEC 2 - 19 EC220001 GENERAL TORQUE SPECIFICATIONS This chart specifies torque for standard fasten- ers with standard I.S.O. pitch threads. Torque specifications for special compone nts or assemblies are included in the applicable sec- tions of this book.
2 - 20 SPEC CABLE ROUTING DIAGRAM EC240000 CABLE ROUTING DIAGRAM 1 Fuel tank breath er hose 2 Oil tank breather hose 3 Clamp 4 Diode 5 Wire harness 6 Hot starter cable 7 Throttle position sensor lead .
2 - 21 SPEC CABLE ROUTING DIAGRAM È Insert the fuel tank breather ho se into the hole in the steering ste m cap. É Pass the oil tank breather hose on t he outside of the AC magneto le ad, neutral switch lead, light switch lead, wire harness, starter motor lea d, neg- ative battery lead and cylinder he ad breather hose.
2 - 22 SPEC Î Fasten the wire harn ess at its white tape. Ï Fasten the wire harne ss, throttle position senso r lead (in the wire harness), starter motor lead and negative batt ery lead. Ð Make sure that the throttle position sensor coupler does not go outside the chassis.
2 - 23 SPEC CABLE ROUTING DIAGRAM × Pass the cylinder h ead breather hose on the inside of the ra diator hose 1 an d on the outside of the radiator pip e (radiator hose 4). Make sure that the cylinder head breath er hose does not go for- ward of the chassis.
2 - 24 SPEC CABLE ROUTING DIAGRAM 1 Hot starter cable 2 Cable guide 3 Throttle cabl e (return) 4 Throttle cable (pull) 5 Ignition coil 6 Coolant reser voir breather hose 7 Rectifier/regulator 8 Coolan.
2 - 25 SPEC CABLE ROUTING DIAGRAM Ì Fasten the coolant reser voir breather hose and carburetor brea ther hoses togethe r. Í Fasten the CDI unit lead.
2 - 26 SPEC CABLE ROUTING DIAGRAM 1 Brake master cylinder 2 Brake hose holder 3 Brake hose È Install the br ake hose s o that its pipe port ion directs as shown an d lightly touches th e projection on the brake caliper. É Pass the brake hose into the brake hose hold ers.
2 - 27 SPEC CABLE ROUTING DIAGRAM 1 Starter moto r lead 2 Negative batte ry lead 3 Wire harness 4 Clamp 5 Taillight lead 6 Coolant reservo ir breather hose 7 Coolant reserv oir hose 8 Positive battery.
2 - 28 SPEC CABLE ROUTING DIAGRAM 1 Throttle cable 2 Brake hose 3 Clamp 4 Light switch lead 5 Hot starter cable 6 Clutch cable 7 Hose guide 8 Clutch switch lead 9 Engine stop switch lead 0 Trip meter cable A Main switch lead B Trip meter C Main switch D Light switch E Start switch lead È Fasten the start switch lead and light switch lead.
3 - 1 INSP ADJ MAINTENANCE INTERVALS EC300000 REGULAR INSPECTION AND ADJUSTMENTS MAINTENANCE INTERVALS The following schedule is intende d as a general guide to maintenance and lubrication. Bear in mind that such factors as weather, terrain, geographical location, and individual usage will alter the required maintenance and lubrication interva ls.
3 - 2 INSP ADJ MAINTENANCE INTERVALS SHIFT FORK, SHIFT CAM, GUIDE BAR Inspect Inspect wea r ROTOR NUT Retighten EXHAUST PIPE, SILENCER, PROTECTOR Inspect and retigh ten Clean Replace * Whichever comes.
3 - 3 INSP ADJ MAINTENANCE INTERVALS *marked: For USA FRONT FORKS Inspect and adjust Replace oil Suspension oil “ 01 ” Replace oil seal FRONT FORK OIL SEAL AND DUST SEAL Clean and lube Lithium bas.
3 - 4 INSP ADJ PRE-OPERATION INSPECTION AND MAINTENANCE EC320000 PRE-OPERATION INSPECTION AND MAINTENANCE Before riding for break-in operation , practice or a race, make sure the machine is in good operating condition. Before using this machine, check the following poin ts.
3 - 5 INSP ADJ EC350000 ENGINE COOLANT LEVEL INSPECTION W ARNING Do not remove the radiator cap 1 , drain bolt and hoses when the engine and radia- tor are hot. Scalding hot fluid and steam may be blown out under pressure, which could cause serious injury.
3 - 6 INSP ADJ COOLANT REPLACEMENT CAUTION: Take care so that coolant does not splash on painted surfaces. If it splashes, wash it away with water. 1. Place a container under the engine. 2. Remove: • Seat Refer to “ SEAT, FUEL TANK AND SIDE COVERS ” section in the CHAPTER 4.
3 - 7 INSP ADJ COOLANT REPLACEMENT 9. Fill: • Radiator • Engine To specified level. CAUTION: • Do not mix more than one type of ethyl- ene glycol antifreeze containing corro- sion inhibitors for aluminum engine. • Do not use wa ter containing impurities or oil .
3 - 8 INSP ADJ RADIATOR CAP INSPECTION/ RADIATOR CAP OPENING PRESS URE INSPECTION 12. Install: • Coolant reservoir cap 13. Start the engine and let it warm up for sev- eral minutes. 14. Turn off the engine and inspect the coolant level. Refer to “ COOLANT LEVEL INSPECTION ” section.
3 - 9 INSP ADJ COOLING SYSTEM INSPECTION/ CLUTCH ADJUSTMENT 2. Apply the specified pressure. 3. Inspect: • Pressure Impossible to maintain the specified pre s- sure for 10 seconds → Replace. Radiator cap opening pressure: 110 kPa (1.1 kg/cm 2 , 15.
3 - 10 INSP ADJ THROTTLE CABLE ADJUSTMENT 2. Adjust: • Clutch lever free play N OTE: • Make minute adjustment on the lever side using the adjuster 2 . • After adjustment, check proper operation of clutch lever. Clutch lever free play adjustment steps: • Loosen the locknuts 1 .
3 - 11 INSP ADJ THROTTLE LUBRICATION/ HOT STARTER LEVER ADJUSTMENT THROTTLE LUBRICATION 1. Remove: • Cover (throttle cable cap) 1 • Cover (grip cap) 2 • Throttle grip cap 3 2.
3 - 12 INSP ADJ AIR FILTER CLEANING AIR FILTER CLEANING N OTE: Proper air filter maintenance is the biggest key to preventing premature engine wear and damage. CAUTION: Never run the engine without the air filter element in place; this would allow dirt and dust to enter the engine and cause rapid wear and possible engine da mage.
3 - 13 INSP ADJ CAUTION: • Do not twist the element when squeezing the element. • Leaving too much of solvent in the ele- ment may result in poor starting. 5. Inspect: • Air filter element Damage → Replace. 6. Apply: • Foam-air-filter oil or equivalent oil to the element N OTE: • Squeeze out the excess oil.
3 - 14 INSP ADJ ENGINE OIL LEVEL INSPECTION ENGINE OIL LEVEL INSPECTION 1. Start the engine, warm it up for several minutes, and then turn off the engine and wait for five minutes. 2. Place the machine on a level place and hold it up on upright position by placin g the suitable stand under the engine.
3 - 15 INSP ADJ ENGINE OIL REPLACEMENT (Except for USA and CDN) CAUTION: • Do not add any chemical additives or use oils with a grade of CD a or higher. • Do not use oils labeled “ ENERGY CON- SERVING II ” b or higher. Engine oil also lubricates the clutch and additives could cause clutch slippage.
3 - 16 INSP ADJ ENGINE OIL REPLACEMENT 4. Remove: • Oil tank cap 1 • Oil filler cap 2 • Frame oil drain bolt 3 • Crankcase oil drain bolt 4 • Oil filter element drain bolt 5 Drain the crankcase and oil tank (frame) of its oil.
3 - 17 INSP ADJ 8. Install: • Copper washer 1 • Oil strainer (frame) 2 • Oil hose 3 • Bolt (oil hose) 4 • Oil hose clamp 5 • Lower engine bracket 9. Install: • Copper washer • Oil filter element drain bolt • Crankcase oil drain bolt • Frame oil drain bolt 10.
3 - 18 INSP ADJ OIL PRESSURE INSPECTION 1. Check: • Oil pressure Checking steps: • Slightly loosen the oil pressure check bolt 1 . • Start the engine and keep it idling until oil starts to seep from the oil pressure check bolt. If no oil comes out after one minute, turn the engine off so it will not seize.
3 - 19 INSP ADJ ENGINE IDLING SPEED ADJUSTMENT/ VALVE CLEARANCE INSPECTION AND ADJUSTMENT ENGINE IDLING SPEED ADJUSTMENT 1. Start the engine and thoroughly warm it up. 2. Attach: • Inductive tachometer To spark plug lead. 3. Adjust: • Engine idling speed Adjustment steps: • Adjust the pilot screw.
3 - 20 INSP ADJ VALVE CLEARANCE INSPECTION AND ADJUSTMENT 3. Remove: • Right radiator Refer to “ RADIA TOR ” section in the CHAPTER 4. • Carburetor Refer to “ CARBURETOR ” section in the CHAPTER 4. • Spark plug • Upper engine bracket • Cylinder head cover Refer to “ CAMSHAFTS ” section in the CHAPTER 4.
3 - 21 INSP ADJ VALVE CLEARANCE INSPECTION AND ADJUSTMENT • Measure the valve clearance e using a feeler gauge 1 . N OTE: Record the measured reading if the clear- ance is incorrect. 6. Adjust: • Valve clearance Adjustment steps: • Remove the camshaft (intake and exhau st).
3 - 22 INSP ADJ VALVE CLEARANCE INSPECTION AND ADJUSTMENT N OTE: The thickness a of each pad is indicated in hundreths of millimeters on the pad upper surface.
3 - 23 INSP ADJ INTAKE EXHAUST MEASURED CLEARA NCE INSTALLED PAD NUMBER 120 125 130 135 140 145 150 155 160 165 17 0 175 180 185 190 195 200 205 210 215 220 225 230 235 240 0.00 ~ 0.04 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 0.
3 - 24 INSP ADJ SPARK ARRESTER CLEANING (For USA) W ARNING • Be sure the exhaust pipe and muffler are cool before cleaning the spark arrest er. • Do not start the engine when cleaning the exhaust system. 1. Remove: • Bolt (spark arrester) 1 1 1 2.
3 - 25 INSP ADJ EC360000 CHASSIS EC361012 BRAKE SYSTEM AIR BLEEDING W ARNING Bleed the brake system if: • The system has been disassembl ed. • A brake hose has been loosened or removed. • The brake fluid is very lo w. • The brake operation is fa ulty.
3 - 26 INSP ADJ FRONT BRAKE ADJUSTMENT 3. Install: • Protector (rear brake) • Diaphragm • Brake master cylinder cap N OTE: If bleeding is difficult, it may be necessary to let the brake fluid system stabilize for a few hours. Repeat the bleeding procedure when the tiny bubbles in the system have disap- peared.
3 - 27 INSP ADJ REAR BRAKE ADJUSTMENT/ FRONT BRAKE PAD INSPECTION AND REPLACEMENT EC364002 REAR BRAKE ADJUSTMENT 1. Check: • Brake pedal height a Out of specification → Adjust. Brake pedal height a : 5 mm (0.20 in) 2. Adjust: • Brake pedal height Pedal height adjustment steps: • Loosen the locknut 1 .
3 - 28 INSP ADJ FRONT BRAKE PAD INSPECTION AND REPLACEMENT • Loosen the pad pin 2 . • Remove the brake hose holder 3 and brake caliper 4 from the front fork. • Remove the pad pin and brake pa ds 5 . • Connect the transparent hose 6 to the bleed screw 7 and place the suitable con- tainer under its end.
3 - 29 INSP ADJ REAR BRAKE PAD INSPECTION AND REPLACEMENT 3. Inspect: • Brake fluid level Refer to “ BRAKE FLUID LEVEL INSPEC- TION ” section. • Install the pad pin plug B . T R . . Pad pin plug: 3 Nm (0.3 m • kg, 2.2 ft • lb) 4. Check: • Brake lever operation A softy or spongy feeling → Bleed brake system.
3 - 30 INSP ADJ REAR BRAKE PAD INSPECTION AND REPLACEMENT • Remove the pad pin 6 and brake pads 7 . • Connect the transparent hose 8 to the bleed screw 9 and place the suitable con- tainer under its end. • Loosen the bleed screw a nd push the brake caliper piston in.
3 - 31 INSP ADJ REAR BRAKE PAD INSULATOR INSPECTION/ BRAKE FLUID LEVEL INSPECTION 3. Inspect: • Brake fluid level Refer to “ BRAKE FLUID LEVEL INSPEC- TION ” section. 4. Check: • Brake pedal operation A softy or spongy feeling → Bleed brake system.
3 - 32 INSP ADJ SPROCKETS INSPECTION/DRIVE CHAIN INSPECTION SPROCKETS INSPECTION 1. Inspect: • Sprocket teeth a Excessive wea r → Replace. N OTE: Replace the drive sprocket, rear wheel sprocket and drive chain as a set. DRIVE CHAIN INSPECTION 1. Remove: • Drive chain 1 N OTE: Remove the drive chain using a drive chain cutter 2 .
3 - 33 INSP ADJ DRIVE CHAIN INSPECTION 5. Check: • Drive chain stiffness a Clean and oil the dr ive chain and hold as illustrated. Stiff → Replace the drive chain. 6. Install: • Chain joint 1 • O-ring 2 • Drive chain 3 N OTE: When installing the drive chain, ap ply the lith- ium soap base grease on the chain joint and O-rings.
3 - 34 INSP ADJ DRIVE CHAIN SLACK ADJUSTMENT DRIVE CHAIN SLACK ADJUSTMENT 1. Elevate the rear wheel by placing the su it- able stand under the engine. 2. Check: • Drive chain slack a Above the seal guard installat ion bolt. Out of specification → Adjust.
3 - 35 INSP ADJ FRONT FORK INSPECTION/ FRONT FORK OIL SEAL AND DUST SEAL CLEANING • Tighten the axle nut while pushing down the drive chain. T R . . Axle nut: 125 Nm (12.5 m • kg, 90 ft • lb) • Tighten the locknuts. T R . . Locknut: 16 Nm (1.6 m • kg, 11 ft • lb) EC36C000 FRONT FORK INSPECTION 1.
3 - 36 INSP ADJ FRONT FORK INTERNAL PRESSURE RELIEVING/FRONT FORK REBOUND DAMPING FORCE ADJUSTMENT FRONT FORK INTERNAL PRESSURE RELIEVING N OTE: If the front fork initial movement feels stiff dur- ing a run, relieve the front fork internal pres- sure.
3 - 37 INSP ADJ FRONT FORK COMPRESSION DAMPING FORCE ADJUSTMENT • STANDARD POSITION: This is the position which is back by the spe- cific number of clicks from the fully turned-in position. * For EUROPE, AUS, NZ and ZA CAUTION: Do not force the adjuster past the minimum or maximum extent of adjustment.
3 - 38 INSP ADJ REAR SHOCK ABSORBER INSPECTION • STANDARD POSITION: This is the position which is back by the spe- cific number of clicks from the fully turned-in position. * For EUROPE, AUS, NZ and ZA CAUTION: Do not force the adjuster past the minimum or maximum extent of adjustment.
3 - 39 INSP ADJ REAR SHOCK ABSORBER SPRING PRELOAD ADJUSTMENT REAR SHOCK ABSORBER SPRING PRELOAD ADJUSTMENT 1. Elevate the rear wheel by placing the su it- able stand under the engine. 2. Remove: • Rear frame 3. Loosen: • Locknut 1 4. Adjust: • Spring preload By turning the adjuster 2 .
3 - 40 INSP ADJ REAR SHOCK ABSORBER REBOUND DAMPING FORCE ADJUSTMENT EC36N014 REAR SHOCK ABSORBER REBOUND DAMPING FORCE ADJUSTMENT 1. Adjust: • Rebound damping f orce By turning the adjuster 1 . Stiffer a → Increase the rebound damp- ing force. (Turn the adjuster 1 i n.
3 - 41 INSP ADJ EC36c000 REAR SHOCK ABSORBER LOW COMPRESSION DAMPING FORCE ADJUSTMENT 1. Adjust: • Low compression damping force By turning the adjuster 1 . Stiffer a → Increase the low compres- sion damping force. (Turn the adjuster 1 in.) Softer b → Decrease the low compres- sion damping force.
3 - 42 INSP ADJ REAR SHOCK ABSORBER HIGH COMPRESSION DAMPING FORCE ADJUSTMENT EC36d000 REAR SHOCK ABSORBER HIGH COMPRESSION DAMPING FORCE ADJUSTMENT 1. Adjust: • High compression damping force By turning the adjuster 1 . Stiffer a → Increase the high compres- sion damping force.
3 - 43 INSP ADJ TIRE PRESSURE CHECK/SPOKES INSPECTION AND TIGHTENING/WHEEL INSPECTION EC36Q000 TIRE PRESSURE CHECK 1. Measure: • Tire pressure Out of specification → Adjust. N OTE: • Check the tire while it is co ld. • Loose bead stoppers allow th e tire to slip off its position on the rim when the tire pressure is low.
3 - 44 INSP ADJ STEERING HEAD INSPECTION AND ADJUSTMENT 2. Inspect: • Bearing free play Exist play → Replace. EC36U013 STEERING HEAD INSPECTION AND ADJUSTMENT 1. Elevate the front wheel by placing a suit- able stand under the engine. 2. Check: • Steer ing stem Grasp the bottom of the forks and gently rock the fork assembly back and forth.
3 - 45 INSP ADJ • Tighten the steering ring nut 3 using steering nut wrench 4 . N OTE: Set the torque wrench to the stee ring nut wrench so that they form a right angle. Steering nut wrench: YU-33975/90890-01403 T R . . Steering ring nut (initi al tightening): 38 Nm (3.
3 - 46 INSP ADJ LUBRICATION LUBRICATION To ensure smooth operation of all components, lubricate your machine durin g setup, after break-in, and after every race.
3 - 47 INSP ADJ ELECTRICAL/SPARK PLUG INSPECTION / IGNITION TIMING CHECK EC370000 ELECTRICAL EC371001 SPARK PLUG INSPECTION 1. Remove: • Spark plug 2. Inspect: • Electrode 1 Wear/damage → Replace. • Insulator color 2 Normal condition is a mediu m to light tan color.
3 - 48 INSP ADJ IGNITION TIMING CHECK 2. Attach: • Timing light • Inductive tachometer To the ignition coil lead (orange le ad 1 ). Timing light: YM-33277-A/90890-03141 Inductive tachometer: YU-8036-B Engine tachometer: 90890-03113 1 3. Check: • Ignition timing 4.
3 - 49 INSP ADJ BATTERY INSPECTION AND CHARGING W ARNING Batteries generate explosive hydrogen gas and contain electrolyte which is made of poisonous and highly caustic sulfuric acid. Therefore, always follow these preventive measures: • Wear protective eye gear when handling or working near batteries.
3 - 50 INSP ADJ BATTERY INSPECTION AND CHARGING N OTE: Since MF batteries are sealed, it is not possi- ble to check the charge state of the battery by measuring the specific gravity of the electro- lyte. Therefore, the charge of the battery has to be checked by measuring the voltage at the battery terminals.
3 - 51 INSP ADJ BATTERY INSPECTION AND CHARGING 4. Measure: • Battery charge È Relationship between the open-circuit voltage and the charging t ime at 20 ° C (68 ° F) (These values var y with the te mperature, th e condition of the batt ery plates, and the elect ro- lyte level.
3 - 52 INSP ADJ BATTERY INSPECTION AND CHARGING 5. Charge: • Battery (refer to the appropriate charging method illustration) W ARNING Do not quick charge a battery.
3 - 53 INSP ADJ BATTERY INSPECTION AND CHARGING Charging method using a variable voltage ch arger.
3 - 54 INSP ADJ BATTERY INSPECTION AND CHARGING Charging method using a constant voltage charger.
3 - 55 INSP ADJ BATTERY REPLACEMENT/FUSE INSPECTION 6. Install: • Battery • Battery band 7. Connect: • Battery leads (to the battery terminals) CAUTION: First, connect the positive lead 1 , then the negative lead 2 . 8. Check: • Battery terminals Dirt → Clean with a wire b rush.
3 - 56 INSP ADJ FUSE INSPECTION 2. Check: • Continuity 2 Reserve fuse Checking steps: • Remove the fuse 1 . • Connect the pocket tester to the fuse and check the continuity. N OTE: Set the pocket tester selector to “ Ω × 1 ” . Pocket tester: YU-3112-C/90890-03112 • If the pocket tester indicates “ ∞ ” , replace the fuse.
3 - 57 INSP ADJ REPLACING THE HEADLIGHT BULBS/ ADJUSTING THE HEADLIGHT BEAMS REPLACING THE HEADLIGHT BULBS 1. Remove: • Headlight Refer to “ SEAT, FUEL TANK AND SIDE COVERS ” section in the CHAPTER 4. 2. Remove: • Headlight bulb holder cover 1 3.
4 - 1 ENG EC400000 ENGINE SEAT, FUEL TANK AND SIDE COVERS Extent of removal: 1 Seat removal 2 Fuel tank removal 3 Side covers removal 4 Headlight removal Extent of removal Order Part name Q ’ ty Remarks SEAT, FUEL TANK AND SIDE COVERS REMOVAL Preparation for removal Turn the fuel cock to “ OFF ” .
4 - 2 ENG REMOVAL POINTS Side cover 1. Remove: • Bolt (side cover) • Left side cover 1 • Right side cover 2 N OTE: Draw the side cover down ward to remove it because its claws a are inserted in th e air fil- ter case.
4 - 3 ENG EXHAUST PIPE AND SILENCER EC4S0000 EXHAUST PIPE AND SILENCER È Except for USA Extent of removal: 1 Silencer removal 2 Exhaust pipe removal Extent of removal Order Part name Q ’ ty Remarks EXHAUST PIPE AND SILENCER REMOVAL Preparation for removal Right side cover Refer to “ SEAT, FUEL TANK A ND SIDE COVERS ” section.
4 - 4 ENG EXHAUST PIPE AND SILENCER INSPECTION Silencer and exhaust pipe 1. Inspect: • Gasket 1 Damage → Replace. 1 ASSEMBLY AND INSTALLATION Silencer and exhaust pipe 1.
4 - 5 ENG RADIATOR EC450001 RADIATOR Extent of removal: 1 Radiator removal Extent of removal Order Part name Q ’ ty Remarks RADIATOR REMOVAL Preparation for removal Drain the coolant. Refer to “ COOLANT REPLACEMENT ” section in the CHAPTER 3. Seat, fuel tank and left side cover Refer to “ SE AT, FUEL TANK AND SIDE COVERS ” section.
4 - 6 ENG RADIATOR EC456000 HANDLING NOTE W ARNING Do not remove the radiator cap when the engine and radiator are ho t. Scalding hot fluid and steam may be blown o ut under pressure, which could cause serious injury.
4 - 7 ENG RADIATOR 3. Install: • Right radiator 1 • Bolt (right radiator) 2 • Radiator hose 3 3 Refer to “ CABLE ROUT ING DIAGRAM ” section in the CHAPTER 2.
4 - 8 ENG CARBURETOR CARBURETOR 9 7 8 1 T R . . 2 Nm (0.2 m • kg, 1.4 ft • Ib) T R . . 11 Nm (1.1 m • kg, 8.0 ft • Ib) T R . . 4 Nm (0.4 m • kg, 2.9 ft • Ib) 5 1 2 6 6 4 4 3 T R . . 3 Nm (0.3 m • kg, 2.2 ft • Ib) T R . . 3 Nm (0.3 m • kg, 2.
4 - 9 ENG CARBURETOR EC468000 CARBURETOR DISASSEMBLY Extent of removal: 1 Carbure tor disassembly Extent of removal Order Part name Q ’ ty Remarks CARBURETOR DISASSEMBLY 1 Carburetor breather hose 4.
4 - 10 ENG CARBURETOR Extent of removal Order Part name Q ’ ty Remarks F Float pin 1 G Float 1 H Needle valve 1 I Main jet 1 J Needle jet 1 K Spacer 1 L Pilot jet 1 M Starter jet 1 N Push rod 1 Pull the push rod.
4 - 11 ENG CARBURETOR HANDLING NOTE CAUTION: Do not loosen the screws (throttle position sensor) 1 except when changing the throt- tle position sensor due to failure because it will cause a drop in engine performance.
4 - 12 ENG CARBURETOR 2. Inspect: • Main jet 1 • Pilot jet 2 • Needle jet 3 • Starter jet 4 • Pilot air jet 5 • Leak jet 6 Damage → Replace. Contamination → Clean. N OTE: • Use a petroleum based solvent for cleaning. Blow out all passages and jets with com- pressed air.
4 - 13 ENG CARBURETOR Float height 1. Measure: • Float height a Out of specification → Adjust. Float height: 8.0 mm (0.31 in) Measurement and adjustment steps: • Hold the carburetor in an upside down position.
4 - 14 ENG Starter plunger 1. Inspect: • Cold starter plunger 1 • Hot starter plunger 2 Wear/damage → Replace. Accelerator pump 1. Inspect: • Diaphragm (accelerator pump) 1 • Spring (accelerator pump) 2 • Accelerator pump cover 3 • O-ring 4 • Push rod 5 Tears (diaphragm)/damage → Replace.
4 - 15 ENG CARBURETOR 2. Install: • Pilot air jet 1 1 3. Install: • Spring 1 1 • Lever 1 2 To lever 2 3 . N OTE: Make sure the spring 1 fits on the stopper a of the lever 2.
4 - 16 ENG CARBURETOR 7. Install: • Spring 1 To throttle shaft 2 . N OTE: Install the bigger hook a of the sp ring fits on the stopper b of the throttle shaft pulley. 8. Install: • Throttle shaft assembly 1 • Washer (metal) 2 • Washer (resin) 3 • Valve lever 4 N OTE: • Apply the fluorochemical grease on the bear- ings.
4 - 17 ENG CARBURETOR 10. Install: • Starter jet 1 • Pilot jet 2 • Spacer 3 • Needle jet 4 • Main jet 5 11. Install: • Needle valve 1 • Float 2 • Float pin 3 N OTE: • After installing the needle valve to the float, install them to the carburetor.
4 - 18 ENG CARBURETOR 14. Install: • Diaphragm (air cut valve) 1 • Spring (air cut valve ) 2 • O-ring 3 • Air cut valve cov er 4 • Screw (air cut valve c over) 5 15.
4 - 19 ENG CARBURETOR 19. Install: • Carburetor breather hose 1 N OTE: Install the carburetor breather hoses to the carburetor so that the hoses do not bend near where they are installed.
4 - 20 ENG 3. Install: • Hot starter plunger 1 T R . . 2 Nm (0.2 m · kg, 1.4 ft · lb) 1 4. Tighten: • Screw (air filter joint) 1 • Screw (carburetor joint) 2 T R . . 3 Nm (0.3 m · kg, 2.2 ft · lb) T R . . 3 Nm (0.3 m · kg, 2.2 ft · lb) 5. Install: • Throttle cable (pull) 1 • Throttle cable (return) 2 6.
4 - 21 ENG 9. Install: • Clamp 1 Refer to “ CABLE ROUT ING DIAGRAM ” section in the CHAPTER 2. 1 CARBURETOR.
4 - 22 ENG CAMSHAFTS CAMSHAFTS CYLINDER HEAD COVER Extent of removal: 1 Cylinder head cover removal Extent of removal Order Part name Q ’ ty Remarks CYLINDER HEAD COVER REMOVAL Preparation for removal Seat and fuel tank Refer to “ SEAT, FUEL TANK AND SIDE COVERS ” section.
4 - 23 ENG CAMSHAFTS CAMSHAFTS Extent of removal: 1 Camshaft removal Extent of removal Order Part name Q ’ ty Remarks CAMSHAFTS REMOVAL 1 Timing mark accessing screw 1 Refer to “ REMOVAL POINTS ” .
4 - 24 ENG CAMSHAFTS REMOVAL POINTS Camshaft 1. Remove: • Timing mark accessing screw 1 • Crankshaft end accessing screw 2 2. Align: • T.D.C. mark With align mark. Checking steps: • Turn the crankshaft count erclockwise with a wrench. • Align the T.
4 - 25 ENG CAMSHAFTS 5. Remove: • Exhaust camshaft 1 • Intake camshaft 2 N OTE: Attach a wire 3 to the timing chain to prevent it from falling into the crankcase. 1 2 3 INSPECTION Camshaft 1. Inspect: • Cam lobe Pitting/scratches/blue discolo ration → Replace.
4 - 26 ENG CAMSHAFTS 4. Measure: • Camshaft-to-cap clearance Out of specification → Measure camshaft outside diameter. Camshaft-to-cap clearance: 0.020 ~ 0.054 mm (0.0008 ~ 0.0021 in) <Limit>: 0.08 mm (0.003 in) Measurement steps: • Install the camshaft onto the cylinder head.
4 - 27 ENG CAMSHAFTS Decompression system 1. Check: • Decompression sy stem Checking steps: • Check that the decompression mecha- nism cam 1 moves smoothly. • Check that the decompression mechanism cam lever pin 2 projects from the camshaft. Timing chain tensioner 1.
4 - 28 ENG CAMSHAFTS • Fit the timing chain 3 onto both camshaft sprockets and install the camshafts on the cylinder head. N OTE: The camshafts should be insta lled onto the cylinder head so that th.
4 - 29 ENG 3. Turn: • Crankshaft Counterclockwise several turns. 4. Check: • Rotor T.D.C. mark Align with the crankcase align mark . • Camshaft match marks Align with the cylinder head surf ace.
4 - 30 ENG 6. Install: • Timing chain guide (top side) 1 • Cylinder head cover gasket 2 • Cylinder head cover 3 • Bolt (cylinder head cover) 4 N OTE: Apply the sealant on the cylinder head cover gasket. 7. Install: • Oil tank breather hose • Cylinder head breather hose • Spark plug T R .
4 - 31 ENG CYLINDER HEAD CYLINDER HEAD Extent of removal: 1 Cylinder head removal Extent of removal Order Part name Q ’ ty Remarks CYLINDER HEAD REMOVAL Preparation for removal Seat and fuel tank Refer to “ SEAT, FUEL TANK AND SIDE COVERS ” section.
4 - 32 ENG CYLINDER HEAD INSPECTION Cylinder head 1. Eliminate: • Carbon deposits (from the combustion chambe rs) Use a rounded scraper. N OTE: Do not use a sharp instrument to avoid damag- ing or scratching: • Spark plug threads • Valve seats 2.
4 - 33 ENG CYLINDER HEAD ASSEMBLY AND INSTALLATION Cylinder head 1. Install: • Dowel pin 1 • Cylinder head gasket 2 • Timing chain guide (exhaust side) 3 • Cylinder head 4 N OTE: While pulling up the timing cha in, install the timing chain guide (exhaust side) and cylinder head.
4 - 34 ENG VALVES AND VALVE SPRINGS VALVES AND VALVE SPRINGS Extent of removal: 1 Valve removal Extent of removal Order Part name Q ’ ty Remarks VALVES AND VALVE SPRINGS REMOVAL Preparation for removal Cylinder head Refer to “ CYLINDER HEAD ” section.
4 - 35 ENG VALVES AND VALVE SPRINGS REMOVAL POINTS Valve lifter and valve cotter 1. Remove: • Valve lifter 1 • Pad 2 N OTE: Identify each lifter 1 and pad 2 position very carefully so that they can be reinstalled in their original place.
4 - 36 ENG VALVES AND VALVE SPRINGS INSPECTION Valve 1. Measure: • Stem-to-guide clearance Out of specification → Replace the valve guide. Stem-to-guide clearance = valve guide inside diameter a – valve stem diameter b Clearance (stem to guide): Intake: 0.
4 - 37 ENG VALVES AND VALVE SPRINGS Valve guide remover: Intake: 4.0 mm (0.16 in) YM-4111/90890-04111 Exhaust: 4.5 mm (0.18 in) YM-4116/90890-04116 Valve guide installer: Intake: 4.0 mm (0.16 in) YM-4112/90890-04112 Exhaust: 4.5 mm (0.18 in) YM-4117/90890-04117 Valve guide reamer: Intake: 4.
4 - 38 ENG VALVES AND VALVE SPRINGS 5. Measure: • Runout (valve stem) Out of specification → Replace. N OTE: • When installing a new valve always replace the guide. • If the valve is removed or replaced always replace the oil seal. 6. Eliminate: • Carbon deposits (from the valve face and valve seat) 7.
4 - 39 ENG VALVES AND VALVE SPRINGS 9. Lap: • Valve face • Valve s eat N OTE: After refacing the valve seat or replacing the valve and valve guide, the valve seat and valve face should be lapped. Lapping steps: • Apply a coarse lapping compound to the valve face.
4 - 40 ENG VALVES AND VALVE SPRINGS Valve spring 1. Measure: • Valve sprin g free length a Out of specification → Replace. 2. Measure: • Compressed spring force a Out of specification → Replace. b Installed length Free length (valve spring): Intake: 37.
4 - 41 ENG VALVES AND VALVE SPRINGS Combination of cylinder head and valve lifter 1. Combination: For this combination, match the paint color on the cylinder head with that on the valve lifter according to the chart below. N OTE: When you purchase a cylinder hea d, you can- not designate its size.
4 - 42 ENG VALVES AND VALVE SPRINGS 3. Install: • Valve cotter N OTE: While compressing the valve spring with a valve spring compressor 1 i nstall the valve cotters. 4. To secure the valve cotters onto the valve stem, lightly tap the valve tip with a piece of wood.
4 - 43 ENG CYLINDER AND PISTON CYLINDER AND PISTON Extent of removal: 1 Cylinder removal 2 Piston removal Extent of removal Order Part name Q ’ ty Remarks CYLINDER AND PISTON REMOVAL Preparation for removal Cylinder head Refer to “ CYLINDER HEAD ” section.
4 - 44 ENG CYLINDER AND PISTON REMOVAL POINTS Piston and piston ring 1. Remove: • Piston p in clip 1 • Piston p in 2 • Piston 3 N OTE: • Put identification marks on each piston head for reference during reinstallation. • Before removing each piston pin, d eburr the clip groove and pin hole area.
4 - 45 ENG CYLINDER AND PISTON Cylinder bore “ C ” 77.00 ~ 77.01 mm (3.0315 ~ 3.0319 in) Taper limit “ T ” 0.05 mm (0.002 in) Out of round “ R ” 0.
4 - 46 ENG CYLINDER AND PISTON Piston ring 1. Measure: • Ring side clearance Use a feeler gauge 1 . Out of specification → Replace the piston and rings as a set. N OTE: Clean carbon from the piston rin g grooves and rings before measuring th e side clearance.
4 - 47 ENG CYLINDER AND PISTON Piston pin 1. Inspect: • Piston pin Blue discoloration/grooves → Replace, then inspect the lubrication system. 2. Measure: • Piston pin-to-piston clearance ASSEMBLY AND INSTALLATION Piston ring and piston 1. Install: • Piston ring Onto the piston.
4 - 48 ENG CYLINDER AND PISTON 2. Position: • Top ring • 2nd ring • Oil ring Offset the piston ring end gaps a s shown. a Top ring end b 2nd ring end c Oil ring end (upper) d Oil ring e Oil ring end (lower) 45 ˚ 135 ˚ 135 ˚ a b ce d 3.
4 - 49 ENG 3. Install: • Cylinder gasket 1 • Cylinder 2 N OTE: Install the cylinder with one hand while com- pressing the piston rings wit h the other hand. CAUTION: • Pass the timing chain 3 through the tim- ing chain cavity. • Be careful not to damage the timing chain guide 4 during installation.
4 - 50 ENG CLUTCH EC4A0000 CLUTCH Extent of removal: 1 Push rod 1, 2 and push lever shaft removal 2 Push pod 1 disassembly 3 Friction plate and clutch plate removal 4 Primary driven gear removal Extent of removal Order Part name Q ’ ty Remarks CLUTCH REMOVAL Preparation for removal Drain the engine oil.
4 - 51 ENG CLUTCH Extent of removal Order Part name Q ’ ty Remarks 10 Friction plate 9 11 Clutch plate 8 12 Cushion spring 1 13 Seat plate 1 14 Nut (clutch boss) 1 Use special tool.
4 - 52 ENG CLUTCH EC4A3000 REMOVAL POINTS Clutch boss 1. Remove: • Nut 1 • Lock washer 2 • Clutch boss 3 N OTE: Straighten the lock washe r tab and use the clutch holding tool 4 to hold the clutch boss.
4 - 53 ENG CLUTCH Friction plate 1. Measure: • Friction plate thickness Out of specification → Replace friction plate as a set. Measure at all four points. EC484600 Clutch plate 1. Measure: • Clutch plate warpage Out of specification → Replace clutch plate as a set.
4 - 54 ENG CLUTCH EC4A5000 ASSEMBLY AND INSTALLATION Push lever shaft 1. Install: • Push lever shaf t 1 • Bolt (push lever shaf t) 2 N OTE: • Apply the lithium soap base grease on the oil seal lip. • Apply the engine oil on the push lever shaft .
4 - 55 ENG 3. Bend the lock washer 1 tab. 4. Install: • Seat plate 1 • Cushion spring 2 N OTE: • Install the seat plate with its chamfere d por- tion a facing the clutch boss 3 . • Install the seat plate so that it is not caught on the step b .
4 - 56 ENG CLUTCH 7. Install: • Push rod 2 1 • Ball 2 • Push rod 1 3 N OTE: Apply the engine oil on the push rod 1, 2 and ball. 8. Install: • Pressure plate 1 9. Install: • Clutch spring 1 • Bolt (clutch spring) 2 N OTE: Tighten the bolts in stage, using a crisscross pattern.
4 - 57 ENG OIL FILTER ELEMENT, WATER PUMP AND R IGHT CRANKCASE COVER OIL FILTER ELEMENT, WATER PUMP AND RIGHT CRANKCASE COVER Extent of removal: 1 Oil filter element removal 2 Water pump removal 3 Rig.
4 - 58 ENG OIL FILTER ELEMENT, WATER PUMP AND R IGHT CRANKCASE COVER Extent of removal Order Part name Q ’ ty Remarks 3 Water pump housing 1 4 Oil delivery pipe 1 5 Bolt (oil hose) 1 6 Kickstarter crank 1 7 Right crankcase cover 1 8 Impeller 1 Refer to “ REMOVAL POINTS ” .
4 - 59 ENG OIL FILTER ELEMENT, WATER PUMP AND R IGHT CRANKCASE COVER REMOVAL POINTS Impeller shaft 1. Remove: • Impeller 1 • Washer 2 • Impeller shaft 3 N OTE: Hold the impeller shaft on its width across the flats a with spanners, etc. and remove the impeller.
4 - 60 ENG OIL FILTER ELEMENT, WATER PUMP AND R IGHT CRANKCASE COVER EC444200 Impeller shaft 1. Inspect: • Impeller shaft 1 Bend/wear/damage → Replace . Fur deposits → Clean. EC444300 Impeller shaft gear 1. Inspect: • Gear teeth a Wear/damage → Replace.
4 - 61 ENG OIL FILTER ELEMENT, WATER PUMP AND R IGHT CRANKCASE COVER 2. Install: • Bearing 1 N OTE: Install the bearing by pressing its o uter race parallel. Impeller shaft 1. Install: • Impeller shaft 1 • Washer 2 • Impeller 3 N OTE: • Take care so that the oil seal lip is not dam- aged or the spring does not slip off its posi- tion.
4 - 62 ENG OIL FILTER ELEMENT, WATER PUMP AND R IGHT CRANKCASE COVER 2. Install: • Right crankcase cover 1 • Bolt (right crankcase cover) 2 N OTE: • Apply the engine oil on the impeller shaft end. • Mesh the impeller shaft gear 3 with primary drive gear 4 .
4 - 63 ENG OIL FILTER ELEMENT, WATER PUMP AND R IGHT CRANKCASE COVER Water pump housing 1. Install: • Dowel pin 1 • O-ring 2 N OTE: Apply the lithium soap base grease on the O- ring. New 2. Install: • Water pump housing 1 • Bolt (water pump housing) 2 T R .
4 - 64 ENG BALANCER BALANCER Extent of removal: 1 Balancer shaft drive gear 2 Balancer shaf t Extent of removal Order Part name Q ’ ty Remarks BALANCER REMOVAL Preparation for removal Primary driven gear Refer to “ CLUTCH ” section. Right crankcase cover Refer to “ OIL FILTER ELEMENT, WATER PUMP AND RIGHT CRANK- CASE COVER ” section.
4 - 65 ENG BALANCER REMOVAL POINTS Balancer shaft drive gear and balancer shaft driven gear 1. Straighten the lock washer tab. 2. Loosen: • Nut (primary drive gear) 1 • Nut (balancer shaft driven gear) 2 N OTE: Place an aluminum plate a between the teeth of the balancer shaft drive gear 3 and driven gear 4 .
4 - 66 ENG BALANCER ASSEMBLY AND INSTALLATION Balancer shaft, balancer shaft drive gear and balancer shaft driven gear 1. Install: • Balancer shaft 1 N OTE: • Apply the engine oil on the bearing.
4 - 67 ENG OIL PUMP OIL PUMP Extent of removal: 1 Oil pump removal 2 Oil pump disassembly Extent of removal Order Part name Q ’ ty Remarks OIL PUMP REMOVAL AND DIS- ASSEMBLY Preparation for removal Primary driven gear Refer to “ CLUTCH ” section.
4 - 68 ENG OIL PUMP Extent of removal Order Part name Q ’ ty Remarks 12 Dowel pin 1 13 Washer 1 14 Oil pump drive shaft 1 15 Rotor housing 1 2.
4 - 69 ENG OIL PUMP INSPECTION Oil pump 1. Inspect: • Oil pump drive gear 1 • Oil pump drive shaft 2 • Rotor housing 3 • Oil pump cover 4 Cracks/wear/damage → Replace.
4 - 70 ENG OIL PUMP ASSEMBLY AND INSTALLATION Oil pump 1. Install: • Oil pump drive shaft 1 • Washer 2 • Dowel pin 3 • Inner rotor 1 4 N OTE: • Apply the engine oil on the oil pump drive shaft and inner rotor 1. • Fit the dowel pin into the groove in the inner rotor 1.
4 - 71 ENG 4. Install: • Outer rotor 2 1 • Dowel pin 2 • Oil pump assembly 3 • Bolt (oil pump a ssembly) [L = 25 mm (0.94 in)] 4 • Bolt (oil pump a ssembly) [L = 30 mm (1.18 in)] 5 N OTE: Apply the engine oil on the outer rotor 2 . T R . . 10 Nm (1.
4 - 72 ENG KICK SHAFT AND SHIFT SHAFT KICK SHAFT AND SHIFT SHAFT Extent of removal: 1 Kick shaft removal 2 Kick shaft disassembly 3 Shift shaft removal 4 Se gment removal Extent of removal Order Part name Q ’ ty Remarks KICK SHAFT AND SHIFT SHAFT R EMOVAL Preparation for removal Oil pump Refer to “ OIL PUMP ” section.
4 - 73 ENG KICK SHAFT AND SHIFT SHAFT Extent of removal Order Part name Q ’ ty Remarks 12 Torsion spring 1 13 Roller 1 14 Shift guide 1 Refer to “ REMOVAL POINTS ” .
4 - 74 ENG KICK SHAFT AND SHIFT SHAFT REMOVAL POINTS Kick shaft assembly 1. Remove: • Kick shaft assem bly 1 N OTE: Unhook the torsion spring 2 from the hole a in the crankcase.
4 - 75 ENG KICK SHAFT AND SHIFT SHAFT EC4B4400 Shift shaft 1. Inspect: • Shift shaft 1 Bend/damage → Replace. • Spring 2 Broken → Replace. EC4C4100 Shift guide and shift lever assembly 1. Inspect: • Shift guide 1 • Shift lever 2 • Pawl 3 • Pawl pin 4 • Spring 5 Wear/damage → Replace.
4 - 76 ENG KICK SHAFT AND SHIFT SHAFT EC4B5111 Stopper lever 1. Install: • Torsion spring 1 • Stopper lever 2 • Bolt (stopper lever) 3 N OTE: Align the stopper lever roller with the slot on segment. Shift guide and shift lever assembly 1. Install: • Spring 1 • Pawl pin 2 • Pawl 3 To shift lever 4 .
4 - 77 ENG KICK SHAFT AND SHIFT SHAFT Shift shaft 1. Install: • Roller 1 • Collar 2 • Torsion spring 3 • Shift shaft 4 N OTE: Apply the engine oil on th e roller and shift shaft. 2. Install: • Shift pedal Refer to “ AC MAGNETO AND STARTER CLUTCH ” section.
4 - 78 ENG KICK SHAFT AND SHIFT SHAFT 3. Install: • Spring gu ide 1 N OTE: Slide the spring guide into the kick shaft, make sure the groove a in the spring guide fits on the stopper of the torsion spring.
4 - 79 ENG AC MAGNETO AND STARTER CLUTCH AC MAGNETO AND STARTER CLUTCH Extent of removal: 1 Starter clutch/wheel gear removal 2 Rotor removal 3 Pickup coil/stator removal Extent of removal Order Part name Q’ty Remarks AC MAGNETO AND STATOR REMOVAL Preparation for removal Drain the engine oil.
4 - 80 ENG AC MAGNETO AND STARTER CLUTCH Extent of removal Order Part name Q ’ ty Remarks 10 Nut (rotor) 1 11 Rotor 1 Use special tool. Refer to “ REMOVAL POINTS ”.
4 - 81 ENG AC MAGNETO AND STARTER CLUTCH EC4L3000 REMOVAL POINTS Rotor 1. Remove: • Nut (rotor) 1 • Plain washer 1 2. Remove: • Rotor 1 Use the rotor puller 2 .
4 - 82 ENG AC MAGNETO AND STARTER CLUTCH 3. Check: • Starter clutch operation • Install the starter clutch drive gear 1 onto the starter clutch 2 and hold the starter clutch. • When turning the starter clutch drive gear counterclockwise É , the starter clutch and the starter clutch drive gear shou ld engage.
4 - 83 ENG AC MAGNETO AND STARTER CLUTCH 2. Install: • Holder 1 • Bolt 2 CAUTION: Pass the pickup coil lead and charging coil lead under the holder while taking care not to allow these leads to get caught with each other.
4 - 84 ENG AC MAGNETO AND STARTER CLUTCH 5. Install: • Plain washer 1 •B e a r i n g 2 • Starter clutch drive gear 3 • Starter clutch 4 N OTE: Apply the engine oil on the plain washer, bear- ing and starter clutch drive gear inner circum- ference.
4 - 85 ENG AC MAGNETO AND STARTER CLUTCH 9. Install: • Shaft 1 • Bearing 2 • Idle gear 1 3 N OTE: Apply the engine oil on the shaft, bearing and idle gear inner circumference. 1 2 3 E 10. Install: • Cover (idle gear 1) 1 • Bolt 2 N OTE: Install the cover (idle gear 1) with its mark a facing upward.
4 - 86 ENG ENGINE REMOVAL EC4M0000 ENGINE REMOVAL Extent of removal Order Part name Q ’ ty Remarks ENGINE REMO VAL Preparation for removal Hold the machine by placing the suitable stand unde r the frame. W ARNING Support the machine securely so there is no danger of it falling over.
4 - 87 ENG ENGINE REMOVAL Extent of removal: 1 Engine removal Extent of removal Order Part name Q ’ ty Remarks Ignition coil Disconnect the AC magneto lea d. Starter motor lead Disconnect at the starter motor side. Negative battery lead Disconnect at the engine side.
4 - 88 ENG ENGINE REMOVAL EC4M3000 REMOVAL POINTS EC4F3100 Drive sprocket 1. Remove: • Nut (drive sprocket) 1 • Lock washer 2 N OTE: • Straighten the lock washer tab. • Loosen the nut while applying the rear brake. 2. Remove: • Drive sprocket 1 • Drive chain 2 N OTE: Remove the drive sprocket together with the drive chain.
4 - 89 ENG ENGINE REMOVAL EC4M5000 ASSEMBLY AND INSTALLATION Engine installation 1. Install: • Engine 1 Install the engine from right side. • Pivot shaft 2 • Engine mounting bolt (lower) 3 • L.
4 - 90 ENG ENGINE REMOVAL Drive sprocket 1. Install: • Drive sprocket 1 • Drive chain 2 N OTE: Install the drive sprocket together with the drive chain. 2. Install: • Lock washer 1 • Nut (drive sprocket) 2 N OTE: Tighten the nut while applying the rear brake.
4 - 91 ENG ENGINE REMOVAL 2. Install: • Spring 1 • Pin 2 • O-ring 3 • Neutral switch 4 • Screw (neutral switch) 5 N OTE: Apply the lithium soap base grease on the O- ring.
4 - 92 ENG CRANKCASE AND CRANKSHAFT CRANKCASE AND CRANKSHAFT Extent of removal: 1 Crankcase separation 2 Crankshaft removal Extent of removal Order Part name Q ’ ty Remarks CRANKCASE AND CRANK- SHAFT R EMOVAL Preparation for removal Engine Refer to “ ENGINE REMOVAL ” section.
4 - 93 ENG CRANKCASE AND CRANKSHAFT Extent of removal Order Part name Q ’ ty Remarks 4 Bolt [L = 45 mm (1.77 in)] 6 Refer to “ REMOVAL POINTS ” . 5 Bolt [L = 55 mm (2.17 in)] 1 6 Bolt [L = 70 mm (2.76 in)] 4 7 Hose guide 1 8 Clutch ca ble hold er 1 9 Right crankcase 1 10 Left crankcase 1 11 Oil strainer 1 12 Crankshaft 1 Use special tool.
4 - 94 ENG CRANKCASE AND CRANKSHAFT CRANKCASE BEARING Extent of removal: 1 Crankcase bearing removal Extent of removal Order Part name Q ’ ty Remarks CRANKCASE BEARING REMOVAL Preparation for removal Transmission Shift cam and shift fork Refer to “ TRANSMISSION, SHIFT CAM AND SHIFT FORK ” section.
4 - 95 ENG CRANKCASE AND CRANKSHAFT REMOVAL POINTS Crankcase 1. Separate: • Right crankcase • Left crankcase Separation steps: • Remove the crankcase bolts 1 , hose guide 2 and clutch cable holder 3 . N OTE: Loosen each bolt 1/4 of a turn at a time and after all the bolts are loosened, remo ve them.
4 - 96 ENG CRANKCASE AND CRANKSHAFT Crankshaft 1. Remove: • Crankshaft 1 Use the crankcase separating t ool 2 . CAUTION: Do not use a hammer to drive out the crankshaft. Crankcase bearing 1. Remove: • Bearing 1 N OTE: • Remove the bearing from the cran kcase by pressing its inner race.
4 - 97 ENG CRANKCASE AND CRANKSHAFT EC4N4201 Crankshaft 1. Measure: • Runout limit a • Small end free play limit b • Connecting rod big end side clearance c • Crank width d Out of specification → Replace. Use the dial gauge and a thickness gauge.
4 - 98 ENG CRANKCASE AND CRANKSHAFT EC4N5000 ASSEMBLY AND INSTALLATION Crankcase bearing 1. Install: • Bearing • Bearing stopper • Bolt (bearing stop per) • Screw (bearing stopper) • Screw [bearing stopper (crankshaft)] 1 To left and right crankcase.
4 - 99 ENG CRANKCASE AND CRANKSHAFT 2. Check: • Shifter operation • Transmission operation Unsmooth operatio n → Repair. 3. Install: • Oil strainer 1 • Bolt (oil strainer) 2 T R . . 10 Nm (1.0 m · kg, 7.2 ft · lb) 4. Apply: • Sealant On the right crankcase 1 .
4 - 100 ENG CRANKCASE AND CRANKSHAFT 6. Tighten: • Hose guide 1 • Clutch cable holder 2 • Bolt (crankcase) 3 N OTE: Tighten the crankcase tightening bolts in stage, using a crisscross pattern.
4 - 101 ENG TRANSMISSION, SHIFT CAM AND SHIFT FORK EC4H0000 TRANSMISSION, SHIFT CAM AND SHIFT FORK Extent of removal: 1 Shift fork, shif t cam, main axle and drive axle rem oval Extent of removal Order Part name Q ’ ty Remarks TRANSMISSION, SHIFT CAM AND SHIFT FORK REMOVAL Preparation for removal Engine Refer to “ ENGINE REMOVAL ” section.
4 - 102 ENG TRANSMISSION, SHIFT CAM AND SHIFT FORK EC4H3000 REMOVAL POINTS EC4H3230 Transmission 1. Remove: • Main axle 1 • Drive axle 2 • Shift cam • Shift fork 3 • Shift fork 2 • Shift fork 1 N OTE: • Remove assembly with the collar 3 installed to the crankcase.
4 - 103 ENG TRANSMISSION, SHIFT CAM AND SHIFT FORK EC4H4810 Shift fork, shift cam and segment 1. Inspect: • Shift fork 1 Wear/damage/scratches → Re place. 2. Inspect: • Shift cam 1 • Segment 2 Wear/damage → Replace. 3. Check: • Shift fork movement Unsmooth operation → Replace shift fork.
4 - 104 ENG TRANSMISSION, SHIFT CAM AND SHIFT FORK 2. Install: • 2nd wheel gear (28T) 1 • 4th wheel gear (25T) 2 • 3rd wheel gear (28T) 3 • 5th wheel gear (22T) 4 • 1st wheel gear (31T) 5 • O-ring 6 To drive axle 7 .
4 - 105 ENG TRANSMISSION, SHIFT CAM AND SHIFT FORK 5. Install: • Shift fork 1 (L) 1 • Shift fork 2 (C) 2 • Shift fork 3 (R) 3 • Shift cam 4 To main axle and drive axle.
5 - 1 CHAS EC500000 CHASSIS EC590000 FRONT WHEEL AND REAR WHEEL EC598000 FRONT WHEEL FRONT WHEEL AND REAR WHEEL Extent of removal: 1 Front wheel removal 2 Whee l bearing removal 3 Brake disc removal E.
5 - 2 CHAS EC598100 REAR WHEEL Extent of removal: 1 Rear wheel removal 2 Wheel bearing removal 3 Brake disc removal Extent of removal Order Part name Q ’ ty Remarks Preparation for removal REAR WHEEL REMOVAL Hold the machine by placi ng the suitable stand unde r the engine .
5 - 3 CHAS FRONT WHEEL AND REAR WHEEL EC593000 REMOVAL POINTS EC523101 Rear wheel 1. Remove: • Wheel 1 N OTE: Push the wheel forward and remove the drive chain 2 . EC513201 Wheel bearing (if necessary) 1. Remove: • Bearing 1 N OTE: Remove the bearing using a ge neral bearing puller 2 .
5 - 4 CHAS FRONT WHEEL AND REAR WHEEL EC514200 Wheel axle 1. Measure: • Wheel axle bends Out of specification → Replace. Use the dial gauge 1 . N OTE: The bending value is shown by one half o f the dial gauge reading. W ARNING Do not attempt to straighten a bent axle.
5 - 5 CHAS FRONT WHEEL AND REAR WHEEL EC595000 ASSEMBLY AND INSTALLATION Front wheel 1. Install: • Bearing (left) 1 • Spacer 2 • Bearing (right) 3 • Oil seal 4 N OTE: • Apply the lithium soap base grease on the bearing and oil seal lip when installing.
5 - 6 CHAS FRONT WHEEL AND REAR WHEEL 5. Install: • Wheel N OTE: • Install the brake disc 1 between the brake pads 2 correctly. • Make sure that the projections a in the t rip meter gear unit fits over the stopper b on the front fork outer tube.
5 - 7 CHAS FRONT WHEEL AND REAR WHEEL 8. Tighten: • Bolt (axle holder) 1 N OTE: Before tightening the bolt, fit the wheel axle to the axle holder by stroking the front fork se v- eral times with the front brake applied. T R . . 23 Nm (2.3 m · kg, 17 ft · lb) 9.
5 - 8 CHAS 11. Install: • Trip meter cable 1 1 Rear wheel 1. Install: • Bearing (right) 1 • Circlip 2 • Spacer 3 • Bearing (left) 4 • Oil seal 5 N OTE: • Apply the lithium soap base grease on the bearing and oil seal lip when installing.
5 - 9 CHAS FRONT WHEEL AND REAR WHEEL 3. Install: • Rear wheel sprocket 1 • Bolt (rear wheel sprocket ) 2 • Washer (rear wheel sprocket) 3 • Nut (rear wheel sprocket) 4 N OTE: Tighten the nuts in stage, using a crisscross pattern. T R . . 50 Nm (5.
5 - 10 CHAS FRONT WHEEL AND REAR WHEEL 8. Install: • Right drive chain puller 1 • Washer 2 • Nut (wheel axle) 3 N OTE: Temporarily tighten the nut (wheel axle) at this point. 9. Adjust: • Drive chain slack a Refer to “ DRIVE C HAIN SLAC K ADJUST MENT ” section in th e CHAPTER 3.
5 - 11 CHAS FRONT BRAKE AND REAR BRAKE EC5A0000 FRONT BRAKE AND REAR BRAKE EC5A8000 FRONT BRAKE Extent of removal: 1 Brake hose removal 2 Brake caliper removal 3 Brake master cylinder removal Extent o.
5 - 12 CHAS EC5A8100 REAR BRAKE Extent of removal: 1 Brake master cylinder removal 2 Brake hose removal 3 Brake caliper removal Extent of removal Order Part name Q ’ ty Remarks Preparation for removal REAR BRAKE REMOVAL Hold the machine by placi ng the suitable stand unde r the engine .
5 - 13 CHAS BRAKE CALIPER DISASSEMBLY È Front É Rear Extent of removal: 1 Front brake caliper disassembly 2 Rear brake caliper disassembly Extent of removal Order Part name Q ’ ty Remarks BRAKE CALIPER DISASSEM- BLY AB 1 Pad pin 1 1 2 Brake pa d 2 2 3 Pad support 1 1 4 Brake caliper piston 2 1 Refer to “ REMOVAL POINTS ” .
5 - 14 CHAS FRONT BRAKE AND REAR BRAKE BRAKE MASTER CYLINDER DISASSEMBLY È Front É Rear Extent of removal: 1 Front brak e master cylin der disassemb ly 2 Rear brake master cylinder disasse mbly Exte.
5 - 15 CHAS FRONT BRAKE AND REAR BRAKE EC5A3000 REMOVAL POINTS Brake fluid 1. Remove: [Front] • Brake master cylinder cap 1 [Rear] • Brake master cylinder cap 1 • Protector N OTE: Do not remove the diaphragm. È Front É Rear 2. Connect the transparent hose 2 to the bleed screw 1 and place a suitable con- tainer under its end.
5 - 16 CHAS FRONT BRAKE AND REAR BRAKE Brake caliper piston seal kit 1. Remove: • Dust seal 1 • Piston seal 2 N OTE: Remove the piston seals and du st seals by pushing them with a finger. CAUTION: Never attempt to pry out piston seals and dust seals.
5 - 17 CHAS Brake caliper 1. Inspect: • Brake caliper cylinder inner surface a Wear/score marks → Replace brake cali- per assembly. È Front É Rear É È 2. Inspect: • Brake caliper piston 1 Wear/score marks → Replace brake cali- per piston assembly.
5 - 18 CHAS 2. Install: • Piston seal 1 • Dust seal 2 W ARNING Always use new piston seals and dust seals. N OTE: Fit the piston seals and dust seals onto t he slot on brake caliper correctly. È Front É Rear È New New É 3. Install: • Brake caliper piston 1 N OTE: Apply the brake fluid on the piston wall.
5 - 19 CHAS FRONT BRAKE AND REAR BRAKE 2. Install: • Copper washer 1 • Union bolt 2 W ARNING Always use new copper washers. CAUTION: Install the brake hose so that its pipe por- tion a directs as shown and lightly touches the projection b on the brake cali- per.
5 - 20 CHAS FRONT BRAKE AND REAR BRAKE 2. Install: • Brake disc cover 1 • Bolt (brake disc cover) 2 T R . . 7 Nm (0.7 m · kg, 5.1 ft · lb) 3. Install: • Brake caliper 1 • Rear wheel 2 Refer to “ FRONT WHEEL AND REAR WHEEL ” section. 4. Tighten: • Pad pin 3 5.
5 - 21 CHAS FRONT BRAKE AND REAR BRAKE 3. Install: • Spring 1 To brake master cylinder piston 2 . N OTE: Install the spring at the smaller dia. sid e. È Front É Rear ÈÉ 4. Install: [Front] • Brake master cylinder kit 1 • Washer 2 • Circlip 3 • Brake master cylinder boot 4 To brake master cylinder 5 .
5 - 22 CHAS FRONT BRAKE AND REAR BRAKE 2. Install: • Brake lever 1 • Bolt (brake lever) 2 • Nut (brake lever) 3 N OTE: Apply the lithium soap base grease on the brake lever sliding surface, bolt and contacting surface of the brake master cylinder p iston.
5 - 23 CHAS FRONT BRAKE AND REAR BRAKE 4. Install: • Pin 1 • Washer 2 • Cotter pin 3 N OTE: After installing, check the brake pedal height. Refer to “ REAR BRAKE ADJUSTMENT ” sec- tion in the CHAPTER 3. New Front brake hose 1. Install: • Brake hose 1 To brake hose holder 2 .
5 - 24 CHAS FRONT BRAKE AND REAR BRAKE 4. Install: • Copper washer 1 • Brake hose 2 • Union bolt 3 W ARNING Always use new copper washers. CAUTION: Install the brake hose so that it contacts the brake master cylinder projection a and that its bent portion b faces downward.
5 - 25 CHAS FRONT BRAKE AND REAR BRAKE 2. Install: • Brake hose holder 1 • Screw (brake hose holder) 2 CAUTION: After installing the brake hose holders, make sure the brake hose does not contact the spring (rear shock absorb er). If it does, correct its twist.
5 - 26 CHAS FRONT BRAKE AND REAR BRAKE 2. Air bleed: • Brake system Refer to “ BRAKE SYSTEM AIR BLEED- ING ” section in the CHAPTER 3. 3. Inspect: • Brake fluid level Fluid at lower level → Fill up. Refer to “ BRAKE FLUID LEVEL INSPEC- TION ” section in the CHAPTER 3.
5 - 27 CHAS FRONT FORK EC550000 FRONT FORK Extent of removal: 1 Front fork removal Extent of removal Order Part name Q ’ ty Remarks Preparation for removal FRONT FORK REMOVAL Hold the machine by placi ng the suitable stand unde r the engine . W ARNING Support the machine securely so there is no danger of it falling over.
5 - 28 CHAS FRONT FORK EC558000 FRONT FORK DISASSEMBLY Extent of removal: 1 Oil seal removal 2 Damper rod removal Extent of removal Order Part name Q ’ ty Remarks FRONT FORK DISASSEMBLY 1 Front fork cap bolt 1 Refer to “ REMOVAL POINTS ” . 2 Fork spring 1 Drain the fork oil.
5 - 29 CHAS FRONT FORK EC556000 HANDLING NOTE N OTE: The front fork requires careful attention. So it is recommended that the fro nt fork be maintained at the dealers.
5 - 30 CHAS FRONT FORK EC553201 Inner tube 1. Remove: • Dust seal 1 • Stopper ring 2 Using slotted-head screwdriver. CAUTION: Take care not to scratch the inner tube. 2. Remove: • Inner tube 1 Oil seal removal steps: • Push in slowly a the inner tube just be fore it bottoms out and then pull it back quickly b .
5 - 31 CHAS EC554200 Base valve 1. Inspect: • Valve assembly 1 Wear/damage → Replace. • O-ring 2 Damage → Replace. EC554400 Fork spring 1. Measure: • Fork spring free length a Out of specification → Replace. EC554502 Inner tube 1. Inspect: • Inner tube surface a Score marks → Repair or replace.
5 - 32 CHAS Front fork cap bolt 1. Inspect: • Front fork cap bolt 1 • O-ring 2 • Air bleed screw 3 Wear/damage → Replace. EC555000 ASSEMBLY AND INSTALLATION Front fork assembly 1. Wash the all parts in a clean solvent. 2. Install: • Damper rod 1 To inner tube 2 .
5 - 33 CHAS 5. Install: • Spring gu ide 1 • Locknut 2 To damper rod 3 . N OTE: • Install the spring guide with its cut a facing upward. • With its thread b facing upward, fully finger tighten the locknut onto the d amper rod.
5 - 34 CHAS FRONT FORK 9. Install: • Slide metal 1 • Oil seal washer 2 To outer tube slot. N OTE: Press the slide metal into the outer tub e with fork seal driver 3 . Fork seal driver: YM-01442/90890-01442 10. Install: • Oil seal 1 N OTE: Press the oil seal into the outer tube with fo rk seal driver 2 .
5 - 35 CHAS FRONT FORK 13. Check: • Inner tube smooth movement Tightness/binding/rough spots → Repeat the steps 2 to 12. 14. Compress the front fork fully. 15. Fill: • Front fork oil Until outer tube top surface with reco m- mended fork oil 1 . CAUTION: • Be sure to use recommended fork oil.
5 - 36 CHAS FRONT FORK 19. Wait ten minutes until the air bubbles have been removed from the front fork, and the oil has dispense evenly in syste m before setting recommended oil level.
5 - 37 CHAS FRONT FORK 21. Measure: • Distance a Out of speci fication → Turn into the lock- nut. Distance a : 20 mm (0.79 in) or more Between damper rod 1 top and locknut 2 top. 22. Loosen: • Rebound damping adjuster 1 N OTE: • Loosen the rebound damping a djuster finger tight.
5 - 38 CHAS FRONT FORK 26. Tighten: • Front fork cap bolt (locknut) 1 N OTE: • While compressing the fork spring, set the thin type spanners 2 between the spacer 3 and spring guide 4 . • Hold the locknut 5 and t ighten the front fork cap bolt with specified torque.
5 - 39 CHAS FRONT FORK 4. Tighten: • Pinch bolt (upper bracket) 1 • Pinch bolt (lower bracket) 2 CAUTION: Tighten the lower bracket to spec ified torque.
5 - 40 CHAS HANDLEBAR EC5B0000 HANDLEBAR Extent of removal: 1 Handlebar removal Extent of removal Order Part name Q ’ ty Remarks Preparation for removal HANDLEBAR REMOVAL Headlight 1 Hot starter ca ble 1 Discon nect at the lever side. 2 Hot starter l ever holder 1 3 Clutch cable 1 Disconnect at the lever side.
5 - 41 CHAS EC5B3000 REMOVAL POINTS Brake master cylinder 1. Remove: • Brake master cylinder bracket 1 • Brake master cylinder 2 CAUTION: • Do not let the brake master cylinder hang on the brake hose. • Keep the brake master cylinder cap side horizontal to prevent air from coming in.
5 - 42 CHAS EC5B5000 ASSEMBLY AND INSTALLATION Handlebar 1. Install: • Handlebar 1 • Handlebar upper holder 2 • Bolt (handlebar upper holder) 3 N OTE: • The handlebar upper ho lder should be installed with the punched mark a forward.
5 - 43 CHAS HANDLEBAR 4. Install: • Grip cap cover 1 • Throttle grip 2 N OTE: Apply the lithium soap base grease on the throttle grip sliding surface. 5. Install: • Throttle cables 1 To tube guide 2 . N OTE: Apply the lithium soap base grease on the throttle cable end and tube guide cable wind- ing porti on.
5 - 44 CHAS HANDLEBAR 8. Install: • Start switch 1 • Brake master cylinder 2 • Brake master cylinder bracket 3 • Bolt (brake master cy linder bracket) 4 • Clamp 5 N OTE: • The start switch and brake master cylinder bracket should be installed according to the dimensions shown.
5 - 45 CHAS HANDLEBAR 11. Install: • Clutch cable 1 • Hot starter cable 2 N OTE: Apply the lithium soap base grease on the clutch cable end and hot starter cable end. 12. Adjust: • Clutch lever free play Refer to “ CLUTCH ADJUSTMENT ” sec- tion in the CHAPTER 3.
5 - 46 CHAS EC560000 STEERING Extent of removal: 1 Lower bracket removal 2 Bearing removal Extent of removal Order Part name Q ’ ty Remarks STEERING REMOVAL W ARNING Support the machine securely so there is no danger of it falling over. Preparation for removal Hold the machine by placing the suitable stand unde r the engine .
5 - 47 CHAS STEERING Extent of removal Order Part name Q ’ ty Remarks 10 Ball race cover 1 11 Upper bearing 1 12 Lower bearing 1 Refer to “ REMOVAL POINTS ” .
5 - 48 CHAS EC563000 REMOVAL POINTS Steering ring nut 1. Remove: • Steering ring nut 1 Use the steering nut wrench 2 . W ARNING Support the steering stem so that it may not fall down. Steering nut wrench: YU-33975/90890-01403 Lower bearing 1. Remove: • Lower bearing 1 Use the floor chisel 2 .
5 - 49 CHAS EC564101 Bearing and ball race 1. Wash the bearings and ball races with a solvent. 2. Inspect: • Bearing 1 • Ball race Pitting/damage → Replace bearings and ball races as a set. Install the bearing in the ball races. Spin the bearings by hand.
5 - 50 CHAS STEERING 4. Install: • Washer 1 • Steering ring nut 2 Tighten the steering ring nu t using the steering nut wrench 3 . Refer to “ STEERING HEAD INSPEC- TION AND ADJUSTMENT ” section in the CHAPTER 3. T R . . 7 Nm (0.7 m · kg, 5.1 ft · lb) 5.
5 - 51 CHAS 8. Install: • Washer 1 • Steering stem nut 2 T R . . 145 Nm (14.5 m · kg, 105 ft · lb) 9. Install: • Steering stem cap 1 10. After tightening the nut, check the steering for smooth movement. If not, adjust the steering by loosening the steering ring nut little by little.
5 - 52 CHAS STEERING 13. Install: • Trip meter 1 • Bolt (trip meter) 2 N OTE: Install the trip meter over the coupler bracket 3 . T R . . 7 Nm (0.7 m · kg, 5.
5 - 53 CHAS SWINGARM EC570000 SWINGARM Extent of removal: 1 Swingarm removal Extent of removal Order Part name Q ’ ty Remarks SWINGARM REMOVAL W ARNING Support the machine securely so there is no danger of it falling over. Preparation for removal Hold the machine by placing the suitable stand unde r the engine .
5 - 54 CHAS SWINGARM EC578000 SWINGARM DISASSEMBLY Extent of removal: 1 Swingarm disassembly 2 Co nnecting rod removal and disassembly 3 Relay arm removal and disassembly Extent of removal Order Part .
5 - 55 CHAS SWINGARM EC573000 REMOVAL POINTS EC573200 Bearing 1. Remove: • Bearing 1 N OTE: Remove the bearing by pressing its outer race. INSPECTION Wash the bearings, bushings, collars, and cov- ers in a solvent. Swingarm 1. Inspect: • Bearing 1 • Bushing 2 Free play exists/unsmooth revolution/rust → Replace bearing and bushing as a set.
5 - 56 CHAS SWINGARM EC574310 Connecting rod 1. Inspect: • Bearing (polylube bearing) 1 • Collar 2 Free play exists/unsmooth revolution/rust → Replace bearing and collar as a set. 2. Inspect: • Bearing (polylube bearing) 1 Loss of solid lubrication → Repla ce.
5 - 57 CHAS SWINGARM 2. Install: • Bearing 1 • Oil seal 2 To relay arm. N OTE: • Apply the molybdenum disulfide grease on the bearing when installing. • Install the bearing by pressing it on the side having the manufacture ’ s mark s or numbers.
5 - 58 CHAS SWINGARM 3. Install: • Collar 1 To connecting rod 2 . N OTE: Apply the molybdenum disulfide grease on the collar and oil seal lips. 4. Install: • Connecting rod 1 • Bolt (connecting rod) 2 • Washer 3 • Nut (connecting ro d) 4 To relay arm 5 .
5 - 59 CHAS SWINGARM 8. Install: • Bolt (connecting rod) 1 • Washer 2 • Nut (connecting ro d) 3 N OTE: • Apply the molybdenum disulfide grease on the bolt. • Do not tighten the nut yet. 9. Install: • Bolt (rear shock absorber-relay arm) 1 • Nut (rear shock absorber-relay arm) 2 N OTE: Apply the molybdenum disulfide grease on the bolt.
5 - 60 CHAS SWINGARM 13. Install: • Bolt (lower chain tensioner) 1 • Washer 2 • Collar 3 • Lower chain tensioner 4 • Nut (lower chain tensioner) 5 T R . . 20 Nm (2.0 m · kg, 14 ft · lb) 14. Install: • Drive chain support 1 • Drive chain support cover 2 • Bolt {drive chain support [ = 50 mm (1.
5 - 61 CHAS REAR SHOCK ABSORBER EC580000 REAR SHOCK ABSORBER Extent of removal: 1 Rear shoc k absorber removal 2 Rear shock absorber disassembly Extent of removal Order Part name Q ’ ty Remarks REAR SHOCK ABSORBER REMOVAL W ARNING Support the machine securely so there is no danger of it falling over.
5 - 62 CHAS REAR SHOCK ABSORBER Extent of removal Order Part name Q ’ ty Remarks 1 Locking tie 2 2 Taillight coupler 1 3 Starting circuit cut-of f relay coupler 1 4 Plastic band 2 5 Clamp (air filter join t) 1 Only loosen ing. 6 Rear fra me 1 7B o l t (rear shock absorber-relay arm) 1 Hold the swingarm.
5 - 63 CHAS HANDLING NOTE W ARNING This rear shock absorber is pro vided with a separate type tank filled with high -pressure nitrogen gas. To prevent the danger of explosion, read and understand the follow- ing information before handling the shock absorber.
5 - 64 CHAS EC583000 REMOVAL POINTS EC583320 Bearing 1. Remove: • Stopper ring (upper bearing) 1 N OTE: Press in the bearing while pressing its outer race and remove the stopper rin g. 2. Remove: • Upper bearing 1 N OTE: Remove the bearing by pressing its outer race.
5 - 65 CHAS REAR SHOCK ABSORBER EC585000 ASSEMBLY AND INSTALLATION EC585300 Bearing 1. Install: • Upper bearing 1 N OTE: Install the bearing pa rallel until th e stopper ring groove appears by pressing its outer rac e.
5 - 66 CHAS REAR SHOCK ABSORBER 2. Tighten: • Adjuster 1 3. Adjust: • Spring length (installed) a * For EUROPE N OTE: The length of the spring (installed) changes 1.5 mm (0.06 in) per turn of the adjuster. CAUTION: Never attempt to turn the adjuster be yond the maximum or minimum setting.
5 - 67 CHAS REAR SHOCK ABSORBER 2. Install: • Bushing 1 • Collar 2 • Dust seal 3 N OTE: • Apply the molybdenum disulfide grease on the bearing. • Apply the lithium soap base grease on the bushing, collars and dust sea ls. • Install the dust seals with their lips facing out- ward.
5 - 68 CHAS REAR SHOCK ABSORBER 8. Install: • Plastic band 1 • Starting circuit cut-o ff relay coupler 2 • Taillight coupler 3 • Locking tie 4 3 2 1 4.
6 - 1 – + ELEC ELECTRICAL COMPONENTS AND WIRING DIAGRAM EC600000 ELECTRICAL EC610000 ELECTRICAL COMPONENTS AND WIRING DIAGRAM EC611000 ELECTRICAL COMPONENTS 1 Headlight 2 Engine stop switch 3 Clutch.
– + ELEC 6 - 2 MAP-CONTROLLED CDI UNIT MAP-CONTROLLED CDI UNIT A map-controlled, CDI ignition syste m is used in the WR250F. The microcomputer in the CDI unit detects t he engine speed and throttle position , thus determining the optimum ignition timing through th e entire operating range.
–+ ELEC 6 - 3 IGNITION SYSTEM EC620000 IGNITION SYSTEM INSPECTION STEPS Use the following steps for checking the possibility of the malfunctioning engine being attributable to ignition system failure and for checking the spark plug which will not spark.
6 - 4 – + ELEC IGNITION SYSTEM SPARK GAP TEST 1. Disconnect the ignition coil from spark plug. 2. Remove the ignition coil cap. 3. Connect the dynamic spark tester 1 (igni- tion checker 2 ) as shown. • Ignition coil 3 • Spark plug 4 È For USA and CDN É Except for USA and CDN 4.
6 - 5 – + ELEC IGNITION SYSTEM 2. Inspect: • Rubber part a Tears/damage → Replace. a MAIN SWITCH INSPECTION 1. Inspect: • Main switch conduct Continuous while the main switch is moved to “ OFF ” → Replace. Not continuous while the main switch is moved to “ ON ” → Replace.
6 - 6 – + ELEC EC626002 IGNITION COIL INSPECTION 1. Remove the ignition coil cap. 2. Inspect: • Primary coil r esistance Out of specification → Replace. Tester (+) lead → Orange lead 1 Tester ( – ) lead → Black lead 2 Primary coil resistance Tester selector position 0.
6 - 7 – + ELEC IGNITION SYSTEM AC MAGNETO INSPECTION 1. Inspect: • Pickup coil resi stance Out of specification → Replace. Tester (+) lead → Red lead 1 Tester ( – ) lead → White lead 2 Pickup coil resistance Tester selector position 248 ~ 372 Ω at 20 ° C (68 ° F) Ω × 100 RW 1 2 NEUTRAL SWITCH INSPECTION 1.
6 - 8 – + ELEC ELECTRIC STARTING SYSTEM STARTING CIRCUIT CUT-OFF SYSTEM OPERATION If the main switch is set to “ ON ” , the starter motor can only operate if at least one of the fol- lowing conditions is met: • The transmission is in neutral (the neutral switch is closed).
– + ELEC 6 - 9 ELECTRIC STARTING SYSTEM INSPECTION STEPS If the starter motor will not operate , use the following inspection step s. *1 marked: Refer to “ FUSE INSPECTION ” section in the CHAPTER 3. *2 marked: Refer to “ BATTERY INSPECTION AND CHAR GING ” section in the CHAPTER 3.
6 - 10 – + ELEC ELECTRIC STARTING SYSTEM EC624000 COUPLERS AND LEADS C ONNECTION INSPECTION 1. Check: • Couplers and lead s connection Rust/dust/looseness/short-circuit → Repair or replace. STARTER MOTOR OPERATION 1. Connect the positive battery terminal 1 and starter motor lead 2 with a jumper lead 3 .
6 - 11 – + ELEC ELECTRIC STARTING SYSTEM STARTER RELAY INSPECTION 1. Remove: • Starter relay 2. Inspect: • Starter relay conduct Use 12 V battery. Continuous while not connected to the battery → Replace. Not continuous while connected to the battery → Replace.
6 - 12 – + ELEC ELECTRIC STARTING SYSTEM DIODE INSPECTION 1. Remove the diode from wire harne ss. 2. Inspect: • Diode continuity Use pocket tester (tester selection position Ω × 1) Incorrect continuity → Replace.
6 - 13 – + ELEC ELECTRIC STARTING SYSTEM STARTER MOTOR 6 7 8 7 8 3 4 5 3 1 2 New B New New 1 Extent of removal: 1 Starter motor disassembly Extent of removal Order Part name Q ’ ty Remarks STARTER MOTOR REMOVAL Exhaust pipe Refer to “ EXHAUST PIPE AND SILENCER ” section in the CHAPTER 4.
6 - 14 – + ELEC ELECTRIC STARTING SYSTEM INSPECTION AND REPAIR 1. Check: • Commutator Dirt → Clean with 600 gr it sandpaper. 2. Measure: • Commutator diameter a Out of specification → Replace the starter motor.
6 - 15 – + ELEC ELECTRIC STARTING SYSTEM 5. Measure: • Brush length a Out of specification → Replace the brushes as a set. Min. brush length: 3.5 mm (0.14 in) 6. Measure: • Brush spri ng force Out of specification → Replace the brush springs as a set.
6 - 16 – + ELEC ELECTRIC STARTING SYSTEM 4. Install: • Gasket 1 • Circlip • Plain washer 2 • Washer (starter motor front cover) 3 • Starter motor front cover 4 N OTE: • For installation, align the projections on the washer with the slots in the front cover.
– + ELEC 6 - 17 CHARGING SYSTEM EC680000 CHARGING SYSTEM EC681001 INSPECTION STEPS If the battery is not charged, use the following inspection steps. *1 marked: Refer to “ FUSE INSPECTION ” section in the CHAPTER 3. *2 marked: Refer to “ BATTERY INSPECTION AND CHAR GING ” section in the CHAPTER 3.
6 - 18 – + ELEC CHARGING SYSTEM EC624000 COUPLERS AND LEADS C ONNECTION INSPECTION 1. Check: • Couplers and lead s connection Rust/dust/looseness/short-circuit → Repair or replace.
– + ELEC 6 - 19 THROTTLE POSITION SENSOR SYSTEM THROTTLE POSITION SENSOR SYSTEM INSPECTION STEPS If the throttle position sensor will not operate, use the following inspection steps.
6 - 20 – + ELEC THROTTLE POSITION SENSOR SYSTEM HANDLING NOTE CAUTION: Do not loosen the screws (throttle position sensor) 1 except when changing the throt- tle position sensor due to failure because it will cause a drop in engine performance. 1 EC624000 COUPLERS AND LEADS C ONNECTION INSPECTION 1.
6 - 21 – + ELEC THROTTLE POSITION SENSOR SYSTEM 3. Inspect: • Throttle position sensor coil variable resistance Check that the resistance in increased as the throttle grip is moved from t he full close position to the fu ll open position. Out of specification → Replace.
6 - 22 – + ELEC THROTTLE POSITION SENSOR SYSTEM 4. Adjust: • Engine idling speed Refer to “ ENGINE IDLING SPEED ADJUST MENT ” section in th e CHAPTER 3. 5. Insert the thin electric conductors 2 (lead) into the throttle position sensor coupler 1 , as shown, and connect the tester to them.
6 - 23 – + ELEC THROTTLE POSITION SENSOR SYSTEM 8. Tighten: • Screw (throttle position sensor) 1 9. Stop the engine. 1 THROTTLE POSITION SENSOR INPUT VOLTAGE INSPECTION 1. Disconnect the throttle position sen sor cou- pler. 2. Start the engine. 3.
– + ELEC 6 - 24 LIGHTING SYSTEM LIGHTING SYSTEM INSPECTION STEPS Refer to the following flow chart wh en inspecting the ignition system for possible p roblems. N OTE: • Replace the bulb and/or bulb socket. 1) Seat 2) Fuel tank • Use the following special tool.
6 - 25 – + ELEC LIGHTING SYSTEM LIGHT SWITCH INSPECTION 1. Inspect: • Light switch conduct No continuous while being → Replace. Continuous while being OFF → Replace. Tester (+) lead → Yellow lead 1 Tester ( – ) lead → Blue lead 2 Y 1 L 2 Tester sele ctor position Ω × 1 OFF AC MAGNETO INSPECTION 1.
7 - 1 TUN EC700000 TUNING EC710000 ENGINE Carburetor setting • The air/fuel mixture will vary depending on atmospheric conditions. Therefore, it is nec- essary to take into consideration the a ir pres- sure, ambient temperature, humidity, et c., when adjusting the carburetor.
7 - 2 TUN CAUTION: • The carburetor is extremely sensitive to foreign matter (dirt, sand, water, etc.). During installation, do not allow foreign matter to get into the carburetor.
7 - 3 TUN SETTING Effects of the setting parts on the throttle valve opening È Closed É Fully open 1 Pilot screw/pilot jet 2 Throttle valve cutaway 3 Jet needle 4 Main jet 1/2 3/4 1/4 1/8 1 2 3 4 ÈÉ Main system The FLATCR carburetor has a primary ma in jet.
7 - 4 TUN SETTING 1 Jet needle 2 Pilot air jet 3 Needle jet 4 Main jet 5 Pilot jet 6 Pilot screw Main j et ad justm ent The richness of the air-fuel mixture at full throt- tle can be set by changing the main jet 1 . * Except for USA If the air-fuel mixture is too rich or too lean, the engine power will drop, resulting in poor accel- eration.
7 - 5 TUN SETTING Pilot screw adjustment The richness of the air-fuel mixtu re with the throttle fully closed to 1/4 open can be set by turning the pilot screw 1 . Turning in the pilot screw will make the mixture lean at low speeds, and turning it ou t will enrich it.
7 - 6 TUN SETTING Effects of adjusting the pilot jet (reference) È Idle É Fully open 1/4 1/2 3/4 +5% – 5% #42 #38 #40 È É Jet needle groove position adjustment Adjusting the jet needle 1 position affects the acceleration when the throttle is 1/ 8 to 3/4 open.
7 - 7 TUN Jet needle adjustment The jet needle is adjusted by changing it . * Except for USA The tapered sections of all jet needles have the same starting positions, but the needles are available with different straight-portion diameters.
7 - 8 TUN Leak jet adjustment (accelerator pump adjustment) The leak jet 1 is a setting part that adjusts the flow of fuel discharged by the accelerator pump.
7 - 9 TUN SETTING EC71Q000 Carburetor setting parts * Except for USA Part name Size Part number Main jet Rich (STD) * (STD) Lean #198 #195 #192 #190 #188 #185 #182 #180 #178 #175 #172 #170 #168 #165 #.
7 - 10 TUN Examples of carburet or setting depending on symptom This should be taken simply for an example. It is necessary to set the carbure tor while checking the operating conditions of the eng ine. Symptom Setting Checking At full throttle Hard breathing Shearing noise Whitish spark plug ↓ Lean mixture Increase main jet calibration no .
7 - 11 TUN EC720000 CHASSIS Selection of the seconda ry reduction ratio (Sprocket) <Requirement for selection of secondary gear reduction ratio> • It is generally said that the secondary gear ratio should be reduced for a lo nger straight portion of a speed course and sh ould be increased for a course with ma ny corners.
7 - 12 TUN SETTING EC72N000 Drive and rear wheel sprockets setting parts * For AUS and NZ Part name Size Part number Drive sprocket 1 (STD) 13T 9383B-13218 Rear wheel sprocket 2 (STD) * (STD) 48T * 48.
7 - 13 TUN SETTING EC722011 Front fork setting The front fork setting should be made depend- ing on the rider ’ s feeling of an actual run and the circuit conditions. The front fork setting includes the follo wing three factors: 1. Setting of air spring ch aracteristics • Change the fork oil level.
7 - 14 TUN SETTING È Air spring character istics in relation to oil level change É Load Ê Stroke 1 Max. oil level 2 Standard oil level 3 Min. oil level EC727020 Spring preload adjustment The spring preload is adjusted by installing the adjustment washer 1 between the fork spring 2 and damper rod 3 .
7 - 15 TUN EC72A001 Setting of spring after replacement As the front fork setting can be easily affected by rear suspension, take care so that the machine front and rear are balanced (in posi- tion, etc.) when setting the front fork. 1. Use of soft spring Generally a soft spring gives a soft riding feeling.
7 - 16 TUN EC72P000 Front fork setting parts • Adjustment washer 1 • Front fork spring 2 [Equal pitch spring] * For EUROPE ** For AUS, NZ and ZA [Unequal pitch spring] N OTE: • The unequal pitch spring is softer in initial characteristic than the equal pitch spring and is difficult to bottom out under full compre s- sion.
7 - 17 TUN EC72B000 Rear suspension setting The rear suspension setting should be made depending on the rider ’ s feeling of an actual run and the circuit conditio ns. The rear suspension setting includes the fol- lowing two factors: 1. Setting of spring preload • Change the set length of t he spring.
7 - 18 TUN SETTING N OTE: • If the machine is new and after it is broken in, the same set length of the spring may change because of the initial fatigue, etc.
7 - 19 TUN CAUTION: When using a rear shock absorber other than currently installed, use the one whose overall length a does not exceed the stan- dard as it may result in faulty performa nce. Never use one whose overall length is greater than standard.
7 - 20 TUN SETTING EC72Q000 Rear shock absorber setting parts • Rear shock spring 1 [Equal pitch spring] * For EUROPE ** For AUS, NZ and ZA [Unequal pitch spring] N OTE: • The unequal pitch spring is softer in initial characteristic than the equal pitch spring and is difficult to bottom out under full compre s- sion.
7 - 21 TUN SETTING EC72H002 Suspension setting • Front fork N OTE: • If any of the following symptoms is experienced with the standard p osition 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 figu re 90 ~ 100 mm (3.
7 - 22 TUN SETTING • Rear shock absorber N OTE: • If any of the following symptoms is experienced with the standard p osition as the base, make resetting by reference to the adjustment procedure given in the same chart. • Adjust the rebound damping in 2-click in crements or decrements.
PRINTED IN JAPAN 2002.11-1.8 × 1 CR (E) PRINTED ON RECYCLED PAPER Y AMAHA MO T OR CO . , L TD . 2500 SHINGAI IW A T A SHIZUOKA JAP AN.
Un punto importante, dopo l’acquisto del dispositivo (o anche prima di acquisto) è quello di leggere il manuale. Dobbiamo farlo per diversi motivi semplici:
Se non hai ancora comprato il Yamaha WR250FM è un buon momento per familiarizzare con i dati di base del prodotto. Prime consultare le pagine iniziali del manuale d’uso, che si trova al di sopra. Dovresti trovare lì i dati tecnici più importanti del Yamaha WR250FM - in questo modo è possibile verificare se l’apparecchio soddisfa le tue esigenze. Esplorando le pagine segenti del manuali d’uso Yamaha WR250FM imparerai tutte le caratteristiche del prodotto e le informazioni sul suo funzionamento. Le informazioni sul Yamaha WR250FM ti aiuteranno sicuramente a prendere una decisione relativa all’acquisto.
In una situazione in cui hai già il Yamaha WR250FM, ma non hai ancora letto il manuale d’uso, dovresti farlo per le ragioni sopra descritte. Saprai quindi se hai correttamente usato le funzioni disponibili, e se hai commesso errori che possono ridurre la durata di vita del Yamaha WR250FM.
Tuttavia, uno dei ruoli più importanti per l’utente svolti dal manuale d’uso è quello di aiutare a risolvere i problemi con il Yamaha WR250FM. Quasi sempre, ci troverai Troubleshooting, cioè i guasti più frequenti e malfunzionamenti del dispositivo Yamaha WR250FM insieme con le istruzioni su come risolverli. Anche se non si riesci a risolvere il problema, il manuale d’uso ti mostrerà il percorso di ulteriori procedimenti – il contatto con il centro servizio clienti o il servizio più vicino.
