Eng | Yamaha WR250FM specification

AC MAGNETO AND STARTER CLUTCH

ENG

Extent of removal										Order	Part name	Q’ty	Remarks

										10	Nut (rotor)	1
										10	Nut (rotor)	1
										11	Rotor	1	Use special tool.
				2						11	Rotor	1	Use special tool.
				2									Refer to “REMOVAL POINTS”.
										12	Woodruff key	1	Refer to “REMOVAL POINTS”.
										12	Woodruff key	1
										13	Starter clutch	1
	1									13	Starter clutch	1
	1									14	Starter clutch drive gear	1
										14	Starter clutch drive gear	1
										15	Bearing	1
										16	Plain washer	1
										17	Idle gear plate	1
										18	Idle gear 2	1
										19	Holder	1
										19	Holder	1
							3			20	Pickup coil	1
										21	Stator	1
										21	Stator	1

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Image 202

Yamaha WR250FM service manual Eng

Contents

WR250FR Page WR250FR Introduction Page Always Wear Protective Apparel Always Maintain Your Machine in Proper Working Order Park the Machine Carefully Turn OFF the Engine Gasoline can Cause InjuryProperly Secure the Machine Before Transporting IT M. Machine Weights Weights of machines without fuel Particularly Important Information Finding the Required HOW to Read Descriptions Manual Format GEN Spec Info Insp ENG ADJ Memo Index Chapter Regular Inspection Adjustments Right Crankcase Cover SEAT, Fuel TankValves and Valve Springs AC Magneto Electrical Components Throttle Position Sensor Description Info Description Engine Serial Number Machine IdentificationVehicle Identification Number Model Label Preparation for Removal and Disassembly Important Information GASKETS, OIL Seals and O-RINGS ALL Replacement PartsLock WASHERS/PLATES and Cotter Pins Bearings and OIL Seals Circlips Checking of Connection Special Tools Part number Tool name/How to use Illustration ACC-QUICK-GS-KT Engine Stop Switch Main SwitchMain switch indicator light Start Switch Kickstarter Crank Clutch LeverShift Pedal Throttle Grip Cold Starter Knob Rear Brake PedalFuel Cock HOT Starter Lever Spark Plug Wrench Light SwitchValve Joint Nipple Wrench Fuel Starting and BREAK-IN AIR Filter MaintenanceStarting a Cold Engine Do not warm up the engine for extended periods of time Restarting an engine after a fall Starting a Warm EngineEngine fails to start About one hour of break-in operation is necessary BREAK-IN ProceduresCylinder and Crankshaft PISTON, RING, VALVES, Camshafts and Gears TORQUE-CHECK Points Cleaning and Storage Cleaning Storage General Specifications 5UM4 CDN, AUS, NZ, ZA FCR-MX37 CDI Maintenance Specifications Engine Head diameter Face width Seat width Margin thickness 1.6 mm Spec USA EUROPE, CDN ZA, AUS, NZ Spec Part to be tightened Thread size ’ty Tightening torque Silencer Chassis USA, CDN Europe AUS, NZ, ZA USA, CDN, ZA EUROPE, AUS, NZ Upper bracket and outer tube Nipple spoke Rear wheel sprocket M4 ⋅ Electrical 5UL-00/DENSO ACM33221 M06/MATSUSHITA Torque General Torque SpecificationsDefinition of Units Mkg Ftlb 10 mm 12 mm 14 mm 17 mm 19 mm 22 mm 16 mm 130 Cable Routing Diagram Spec Spec Spec Spec Spec Spec Spec Spec Maintenance Intervals Insp ADJ Maintenance Intervals ADJ Cooling System Marked For USA PRE-OPERATION Inspection and Maintenance General Inspection and Maintenance Engine Coolant ReplacementDo not remove the radiator cap when the engine is hot Coolant Level Inspection Coolant Replacement Fill Radiator Engine To specified level Radiator CAP Inspection Radiator CAP Opening Pressure Inspection Cooling System Inspection Clutch AdjustmentRadiator cap opening pressure KPa 1.1 kg/cm2, 15.6 psi Standard pressure KPa 1.8 kg/cm2, 25.6 psi Throttle Cable Adjustment Throttle Cable AdjustmentClutch lever free play adjustment steps Throttle grip free play adjustment steps Throttle Lubrication HOT Starter Lever AdjustmentHot starter lever free play adjustment steps Hot starter lever free play a 3 ~ 6 mm 0.12 ~ 0.24 AIR Filter Cleaning AIR Filter Cleaning Insp ADJ Engine OIL Level Inspection Engine OIL Level Inspection Engine OIL Replacement Engine OIL ReplacementAPI Standard Replacement steps Oil filter element cover 10 Nm 1.0 m kg, 7.2 ft lb Install Copper washer 1 New Oil strainer frame Pilot Screw Adjustment OIL Pressure Inspection Engine Idling Speed Adjustment Valve Clearance Inspection and Adjustment Valve Clearance Inspection and Adjustment Mm increments Pad range Pad Availability Increments 20 mm40 mm Last digit of pad Rounded value Example Intake Exhaust Spark Arrester Cleaning For USA Chassis CHASSIS/BRAKE System AIR BleedingBrake System AIR Bleeding Front Brake Adjustment Front Brake AdjustmentBrake lever position adjustment steps Rear Brake Adjustment Front Brake PAD Inspection and Replacement Do not reuse the drained brake fluid Front Brake PAD Inspection and ReplacementBleed screw Nm 0.6 m kg, 4.3 ft lb Pad pin plug Nm 0.3 m kg, 2.2 ft lb Rear Brake PAD Inspection and ReplacementRear Brake PAD Inspection and Replacement Brake pad thickness Mm 0.25 in Limit 1.0 mm 0.04 Pad pin 18 Nm 1.8 m kg, 13 ft lb Rear Brake PAD Insulator Inspection Brake Fluid Level Inspection Drive Chain Inspection Sprockets INSPECTION/DRIVE Chain InspectionSprockets Inspection Drive chain length 10 links Limit 150.1 mm 5.91 Drive Chain Inspection Drive chain slack adjustment steps Drive Chain Slack AdjustmentDrive Chain Slack Adjustment Drive chain slack 40 ~ 50 mm 1.6 ~ 2.0 Locknut 16 Nm 1.6 m kg, 11 ft lb Front Fork OIL Seal and Dust Seal CleaningAxle nut 125 Nm 12.5 m kg, 90 ft lb Front Fork Inspection Front Fork Rebound Damping Force Adjustment Front Fork Internal Pressure Relieving Front Fork Compression Damping Force Adjustment Standard position 9 clicks out Clicks out Standard position 14 clicks out Clicks out Rear Shock Absorber InspectionRear Shock Absorber Inspection Rear Shock Absorber Spring Preload Adjustment Standard position About 7 clicks out About 10 clicks out Rear Shock Absorber LOW Compression Damping Force Adjustment Standard position About 9 clicks out About 10 clicks out Standard position About 1-1/4 turns out Spokes Inspection and Tightening Tire Pressure CheckStandard tire pressure KPa 1.0 kgf/cm2, 15 psi Wheel Inspection Steering ring nut adjustment steps Steering Head Inspection and AdjustmentSteering Head Inspection Adjustment Steering nut wrench YU-33975/90890-01403 38 Nm 3.8 m kg, 27 ft lb Steering nut wrenchAvoid over-tightening Lubrication Lubrication Spark plug gap ~ 0.8 mm 0.028 ~ 0.031 ElectricalSpark Plug Inspection Ignition Timing Check Ignition Timing Check Keep Batteries and Electrolyte OUT of Reach of Children Battery Inspection and ChargingBattery Inspection and Charging First AID in Case of Bodily Contact External Remove Battery band Measurement steps Example Charge Battery Charging method using a variable voltage charger Charging method using a constant voltage charger First, connect the positive lead 1, then the negative lead Battery REPLACEMENT/FUSE InspectionBattery Replacement Recommended lubricant Lithium soap base grease Pocket tester YU-3112-C/90890-03112 Fuse InspectionItems Amperage rating ’ty Adjusting steps Adjusting the Headlight BeamsReplacing the Headlight Bulbs SEAT, Fuel Tank and Side Covers SEAT, Fuel Tank and Side Covers Removal Removal Points Side cover Exhaust Pipe and Silencer Exhaust Pipe Silencer Removal Assembly and Installation Silencer and exhaust pipe Silencer and exhaust pipe Radiator Radiator Removal Handling Note Assembly and Installation RadiatorRadiator Install Right radiator Bolt right radiator Carburetor Carburetor Removal Carburetor Disassembly Carburetor Disassembly ENG Pilot screw Carburetor Jet needle Needle valveThrottle valve Standard clip position No.4 Groove Float height Float height Mm 0.31 Measurement and adjustment stepsFloat Accelerator pump Assembly and Installation CarburetorStarter plunger Air cut valve ENG ENG Pilot screw Turns out example 8 turns out ENG Carburetor installation Accelerator pump timing adjustment Adjustment stepsThrottle valve height Mm 0.06 Carburetor ENG Carburetor ENG Cylinder Head Cover CamshaftsCylinder Head Cover Removal Camshafts Camshafts Removal Camshaft Runout camshaft Less than 0.03 mm 0.0012 Bolt camshaft cap 10 Nm 1.0 m kg, 7.2 ft lb Decompression system Assembly and Installation CamshaftInstallation steps Timing chain tensioner CA U TI O N Bolt timing chain tensioner Camshafts ENGTensioner cap bolt Quick gasket ACC-QUICK-GS-KT Yamaha Bond No Cylinder Head Cylinder Head Removal Cylinder head Assembly and Installation Cylinder head Valves and Valve Springs Valves and Valve Springs Removal Valve lifter and valve cotter Valve spring compressor YM-4019/90890-04019 Valve Margin thickness Intake Mm 0.0315 in Exhaust Mm 0.0276 Runout limit 01 mm 0.0004 Lapping steps Valve spring Combination Cylinder head mark Valve lifter mark b Color Assembly and Installation Valve and valve springCombination of cylinder head and valve lifter Yellow Valve spring compressor YM-4019/90890-04019 Cylinder and Piston Cylinder and Piston Removal Do not use a hammer to drive the piston pin out Piston and piston ringPiston pin puller set YU-1304/90890-01304 Cylinder and piston 2nd step Cylinder bore C 77.00 ~ 77.01 mm 0315 ~ 3.031905 mm 0.002 Piston size P Limit Piston ringSide clearance End gap Piston pin Inside diameter piston 16.002 ~ 16.013 mm 0.6300 ~ 0.6304 Cylinder Install Bolt cylinder Clutch Clutch Removal ENG Clutch holding tool YM-91042/90890-04086 Clutch housing and bossClutch boss Primary driven gear Warp limit Mm 0.004 Push lever shaft Friction plateClutch plate Push rod Assembly and Installation Push lever shaft Clutch ENG Install Push rod 2 Ball Push rod 1 OIL Filter ELEMENT, Water Pump and Right Crankcase Cover ENG Oil seal Impeller shaftOil delivery pipe Impeller shaft gear Assembly and Installation Oil sealBearing Right crankcase cover Kickstarter crank Water pump housing Oil filter element Balancer Balancer Removal Balancer shaft drive gear and balancer shaft driven gear Balancer shaft Primary drive gear Nut primary drive gear OIL Pump Removal and DIS Assembly OIL Pump ENG Oil pump Assembly and Installation Oil pump Bolt oil pump assembly L = 30 mm 1.18 Kick Shaft and Shift Shaft Kick Shaft and Shift Shaft Removal ENG Segment Kick shaft assemblyShift guide and shift lever assembly Kick shaft and ratchet wheel Shift shaft Assembly and InstallationStopper lever Install Torsion spring Stopper lever Bolt stopper lever Kick shaft assembly Kick idle gear AC Magneto and Starter Clutch AC Magneto and Stator Removal ENG AC magneto RotorRotor puller YM-04141/90890-04141 Woodruff key Assembly and Installation AC magneto and starter clutch Install Holder Bolt Plain washer rotor Nut rotor Bolt engine guard rear Engine Removal Engine Removal ENG Drive sprocket Engine removal Assembly and Installation Engine installation Brake pedal Oil hose and neutral switch Nm 0.4 m · kg, 2.9 ft · lb Crankcase and Crankshaft Crankcase and Crank Shaft Removal ENG Crankcase Bearing Crankcase Bearing Removal Crankcase Separation steps Crankcase separating tool YU-1135-A/90890-01135 CrankshaftTiming chain and timing chain guide Dial gauge and stand YU-3097/90890-01252 Standard Limit Assembly and Installation Crankcase bearing Do not use a hammer to drive in the crank- shaft Apply Sealant On the right crankcase Tighten Hose guide Clutch cable holder Bolt crankcase TRANSMISSION, Shift CAM and Shift Fork TRANSMISSION, Shift CAM Shift Fork Removal Transmission Gears Assembly and Installation Transmission Shift fork, shift cam and segment ENG ENG Front Wheel Front Wheel and Rear Wheel ChasFront Wheel and Rear Wheel Front Wheel Removal Rear Wheel Rear Wheel Removal Wheel bearing if necessary Rear wheelWheel Do not attempt to straighten a bent axle Wheel axleWheel axle bending limit 0.5 mm 0.020 Brake disc Front wheel 105 Nm 10.5 m · kg, 75 ft · lb Tighten Bolt axle holder Install Trip meter cable 50 Nm 5.0 m · kg, 36 ft · lb 125 Nm 12.5 m · kg, 90 ft · lb Front Brake Front Brake and Rear Brake ChasFront Brake and Rear Brake Front Brake Removal Rear Brake Rear Brake Removal Brake Caliper Disassembly Brake Caliper Disassem BLY Brake Master Cylinder Disassembly Brake Master Cylinder Disassembly Brake fluid Brake master cylinder Brake caliper piston seal kitUse only new brake fluid Brake caliper Brake hose Always use new piston seals and dust seals Front brake caliper Rear brake caliper Brake master cylinder kit Front brake master cylinder Rear brake master cylinder Front brake hose CAU TI on Always use new copper washers CAU T ION Install rear brake only Protector Bolt protector Front Fork Front Fork ChasFront Fork Removal Front Fork Disassembly Front Fork Disassembly Front fork cap bolt Oil seal removal steps Inner tubeTake care not to scratch the inner tube Damper rod Fork spring free length 460 mm 18.1 in Limit 455 mm 17.9 Base valveFork spring Inner tube bending limit 0.2 mm 0.008 Assembly and Installation Front fork assembly Front Fork Chas Fork seal driver YM-01442/90890-01442 Front Fork Chas Front Fork Chas Front Fork Chas Installation Front fork top end standard a 5 mm 0.20 10 mm 0.39 Tighten Pinch bolt upper bracket Handlebar Handlebar ChasHandlebar Removal Grip Handlebar Assembly and Installation Handlebar Install Grip cap cover Cover throttle cable cap Hot starter lever holder Bolt hot starter lever holder Handlebar Chas Steering Steering ChasSteering Removal Steering Chas Ball race Steering ring nutTake care not to damage the steering shaft thread Steering stem Bearing and ball race Lower bracket Install Washer Steering ring nut Install Washer Steering stem nut Install Trip meter Bolt trip meter Swingarm Swingarm ChasSwingarm Removal Swingarm Disassembly Swingarm Disassembly Swingarm Relay arm Connecting rod Bearing and oil seal Installed depth of bearings a 5 mm 0.20 Installed depth of bearings a 5 mm 0.20 Swingarm 80 Nm 8.0 m · kg, 58 ft · lb Tighten Nut relay arm Bolt drive chain support cover = 10 mm 0.39 Rear Shock Absorber Rear Shock Absorber ChasRear Shock Absorber Removal Starting circuit cut-off relay coupler Handling Note Rear shock absorber Install Spring Upper spring guide Lower spring guide Tighten Adjuster Spring length installed a Bolt rear frame lower Rear Shock Absorber Chas Wiring Diagram Electrical Components and Wiring DiagramColor Code MAP-CONTROLLED CDI Unit Function of Component Ignition System Inspection Steps Spark GAP Test Engine Stop Switch InspectionIgnition System Elec + COUPLERS, Leads and Ignition Coil Connection Inspection Battery + lead → Red/Black lead 1 Battery lead → Black lead Main Switch InspectionTester + lead → Red lead Tester lead → Brown lead Resistance Position 08 ~ 0.10 Ω at 20 C 68 F Ignition Coil InspectionResistance Position ~ 6.8 kΩ at Resistance Position 248 ~ 372 Ω at 20 C 68 F Neutral Switch InspectionAC Magneto Inspection Tester + lead → Sky blue lead 1 Tester lead → Ground Electric Starting System Starting Circuit CUT-OFF System Operation Inspection Steps Couplers and Leads Connection Inspection BatteryTo battery Starter Motor Operation Starter Relay Inspection Clutch Switch InspectionPull Free Electric Starting System Elec + Start Switch InspectionDiode Inspection Starter Motor Removal Starter MotorStarter Motor Disassem BLY Min. commutator diameter 16.6 mm 0.65 Inspection and RepairMica undercut 1.5 mm 0.06 Be careful not to damage the brush during installation AssemblyMin. brush length Mm 0.14 New Charging System Voltage Position 14.1 ~ 14.9 V at DCV-20 000 r/min Charging Voltage InspectionTester + lead → Red lead Tester lead → Black lead Resistance Position 288 ~ 0.432 Ω at 20 C 68 F Throttle Position Sensor System Throttle Position Sensor Coil Inspection Throttle Position Sensor System Elec +~ 6 kΩ at Coil variable resistance Throttle Position Sensor Replacement and AdjustmentAt 20 C 68 F 58 ~ 0.78 Tester + lead → Yellow lead Tester lead → Black leadThrottle position Tester selector DCV Throttle Position Sensor Input Voltage Inspection ~ 6 DCV-20 Lighting System OFF Light Switch InspectionRECTIFIER/REGULATOR Inspection Setting Carburetor setting Settings Main system Effects of the setting parts on the throttle valve openingPilot system Standard main jet #185 #172 Main jet adjustmentEffects of changing the main jet reference Setting T U N Effects of adjusting the pilot jet reference Jet needle groove position adjustment Obdvs Obelp Jet needle adjustmentStandard jet needle Effects of changing the jet needle reference Leak jet adjustment accelerator pump adjustment Standard leak jet #90 Relationship with throttle opening STD Examples of carburetor setting depending on symptom Selection of the secondary reduction ratio Sprocket Standard secondary reduction ratio 52/13 Sprocket 9383B-132185GS-25448-50 5NY-25448-00 Front fork setting Change in level and characteristics of fork oil Spring preload adjustment Setting of spring after replacement Mark Part NumberSpring Rate Choosing set length Rear suspension settingStandard figure 90 ~ 100 mm 3.5 ~ 3.9 Setting of spring after replacement Setting Adjustment b Rear shock absorber setting partsSpring Free Extent Suspension setting One passenger is astride seat Printed on Recycled Paper Shingai Iwata Shizuoka Japan