Yamaha YZ250F(Z) Owner'S Service Manual Download Page 99

Page: 99 / 196

4-25

CYLINDER AND PISTON

REMOVING THE CYLINDER AND PISTON

Order

Part name

Q'ty

Remarks

Cylinder head

Refer to "CYLINDER HEAD" section.

Bolt (cylinder)

Cylinder

Piston pin clip

Refer to removal section.

Piston pin

Refer to removal section.

Piston

Refer to removal section.

Piston ring set

Refer to removal section.

Summary of Contents for YZ250F(Z)

Page 1: ...DI SERVIZIO DEL PROPRIETARIO PRINTED IN JAPAN 2009 05 2 0 1 CR E F G H YZ250F Z 2010 Il convient de lire attentivement ce manuel avant la premi re utilisation du v hicule Read this manual carefully be...

Page 2: ...le Le manuel doit tre remis avec le v hicule en cas de vente de ce dernier Bitte lesen Sie diese Bedienungsanleitung sorgf ltig durch bevor Sie das Fahrzeug in Betrieb nehmen Diese Bedienungsanleitung...

Page 3: ...Z250F Z 2010 2010 17D 28199 30 E0 17D 28199 30 E0 OWNER S SERVICE MANUAL OWNER S SERVICE MANUAL Read this manual carefully before operating this vehicle Read this manual carefully before operating thi...

Page 4: ......

Page 5: ...S SERVICE MANUAL 2009 by Yamaha Motor Co Ltd 1st Edition May 2009 All rights reserved Any reprinting or unauthorized use without the written permission of Yamaha Motor Co Ltd is expressly prohibited P...

Page 6: ...acter istics THIS MACHINE IS DESIGNED TO BE RIDDEN BY THE OPERATOR ONLY Do not carry passengers on this machine ALWAYS WEAR PROTECTIVE APPAREL When operating this machine al ways wear an approved helm...

Page 7: ...n to find the required fore edge symbol mark and go to a page for required item and de scription MANUAL FORMAT All of the procedures in this manual are organized in a sequential step by step format Th...

Page 8: ...informa tion the step by step format sup plements 5 are given in addition to the exploded diagram and job instruction chart ILLUSTRATED SYMBOLS Refer to the illustration Illustrated symbols 1 to 7 are...

Page 9: ...TABLE OF CONTENTS GENERAL INFORMATION 1 SPECIFICATIONS 2 REGULAR INSPECTION AND ADJUSTMENTS 3 ENGINE 4 CHASSIS 5 ELECTRICAL 6 TUNING 7...

Page 10: ...INE 3 6 CHASSIS 3 14 ELECTRICAL 3 24 CHAPTER 4 ENGINE SEAT FUEL TANK AND SIDE COVERS 4 1 EXHAUST PIPE AND SILENCER 4 3 RADIATOR 4 5 CARBURETOR 4 7 CAMSHAFTS 4 14 CYLINDER HEAD 4 19 VALVES AND VALVE SP...

Page 11: ...1 1 LOCATION OF IMPORTANT LABELS GENERAL INFORMATION LOCATION OF IMPORTANT LABELS Please read the following important labels carefully before operating this vehicle CANADA 1...

Page 12: ...1 2 LOCATION OF IMPORTANT LABELS EUROPE...

Page 13: ...1 3 LOCATION OF IMPORTANT LABELS AUS NZ ZA...

Page 14: ...ins high pressure nitrogen gas Mishandling can cause explosion Do not incinerate puncture or open Turn off the main switch after riding to avoid draining the battery Use unleaded gasoline only Measure...

Page 15: ...ge without notice 1 Clutch lever 2 Hot starter lever 3 Front brake lever 4 Throttle grip 5 Radiator cap 6 Fuel tank cap 7 Engine stop switch 8 Kickstarter crank 9 Fuel tank 10 Radiator 11 Coolant drai...

Page 16: ...oint 1 prevents fuel from flowing out and is installed to the fuel tank breather hose In this installation make sure the arrow faces the fuel tank and also downward SPARK PLUG WRENCH This spark plug w...

Page 17: ...mped letters must be on the side exposed to view When in stalling oil seal s apply a light coating of lightweight lithium base grease to the seal lip s Oil the bearings liberally when installing Do no...

Page 18: ...se separating tool YU 1135 A 90890 01135 These tool is used to remove the crankshaft from either case Flywheel puller YM 1189 90890 01189 This tool is used to remove the fly wheel magneto Rotor holdin...

Page 19: ...1500 90890 01500 This tool is used to loosen or tighten the base valve Cap bolt ring wrench YM 01501 90890 01501 This tool is used to loosen or tighten the damper assembly Fork seal driver YM A0948 90...

Page 20: ...ss securing nut Valve guide remover Intake 4 0 mm 0 16 in Exhaust 4 5 mm 0 18 in YM 4111 90890 04111 YM 4116 90890 04116 This tool is needed to remove and install the valve guide Valve guide installer...

Page 21: ...ecessary for checking the ignition system compo nents Digital tachometer YU 39951 B 90890 06760 This tool is needed for observing en gine rpm YAMAHA Bond No 1215 Three Bond No 1215 90890 85505 This se...

Page 22: ...grip toward you for deceleration turn it away from you FRONT BRAKE LEVER The front brake lever 1 is located on the right handlebar Pull it toward the handlebar to activate the front brake REAR BRAKE...

Page 23: ...while kick ing the kickstarter crank Other wise the kickstarter crank may kick back 6 Return the cold starter knob to its original position and run the en gine at 3 000 5 000 r min for 1 or 2 minutes...

Page 24: ...2 open low to me dium speed for about one hour 6 Restart the engine and check the operation of the machine through out its entire operating range Re start the machine and operate it for about 10 to 15...

Page 25: ...nk type Assembly of links Link to frame Link to rear shock absorber Link to swingarm Installation of rear shock absorber Rear shock absorber to frame Installation of swingarm Tightening of pivot shaft...

Page 26: ...th a vinyl uphol stery cleaner to keep the cover pliable and glossy 8 Automotive wax may be applied to all painted or chromed surfac es Avoid combination cleaner waxes as they may contain abra sives 9...

Page 27: ...cooled 4 stroke DOHC Cylinder arrangement Single cylinder forward inclined Displacement 250 cm3 8 80 Imp oz 8 45 US oz Bore stroke 77 0 53 6 mm 3 03 2 11 in Compression ratio 13 5 1 Starting system Ki...

Page 28: ...EUROPE AUS NZ ZA Frame type Bilateral beam Caster angle 27 5 27 2 27 4 Trail 120 2 mm 4 73 in 117 4 mm 4 62 in 119 6 mm 4 71 in Tire Type With tube Size front 80 100 21 51M Size rear 100 90 19 57M Ti...

Page 29: ...utside diameter 21 959 21 972 mm 0 8645 0 8650 in Shaft to cap clearance 0 028 0 062 mm 0 0011 0 0024 in 0 08 mm 0 003 in Cam dimensions Intake A 30 330 30 430 mm 1 1941 1 1980 in 30 230 mm 1 1902 in...

Page 30: ...EX 0 9 1 1 mm 0 0354 0 0433 in 1 6 mm 0 0630 in D margin thickness IN 0 8 mm 0 0315 in D margin thickness EX 0 7 mm 0 0276 in Stem outside diameter IN 3 975 3 990 mm 0 1565 0 1571 in 3 945 mm 0 1553 i...

Page 31: ...in Compressed force installed IN 99 114 N at 28 98 mm 9 9 11 4 kg at 28 98 mm 22 27 25 57 lb at 1 14 in Compressed force installed EX 126 145 N at 28 30 mm 12 6 14 5 kg at 28 30 mm 28 44 31 97 lb at...

Page 32: ...0 0012 0 0026 in 0 12 mm 0 005 in 2nd ring Type Taper Dimensions B T 0 80 2 75 mm 0 03 0 11 in End gap installed 0 30 0 45 mm 0 012 0 018 in 0 80 mm 0 031 in Side clearance 0 020 0 055 mm 0 0008 0 002...

Page 33: ...Cam drum and guide bar Guide bar bending limit 0 05 mm 0 002 in Kickstarter Type Kick and ratchet type Carburetor USA CDN EUROPE AUS NZ ZA Type manufacturer FCR MX37 KEIHIN I D mark 17D5 50 17D6 60 M...

Page 34: ...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 454 mm 17 9 in 449 mm 17 7...

Page 35: ...0 mm 9 84 0 12 in 250 2 5 mm 9 84 0 10 in Pad thickness 4 4 mm 0 17 in 1 0 mm 0 04 in Master cylinder inside dia 9 52 mm 0 375 in Caliper cylinder inside dia 22 65 mm 0 892 in 2 Brake fluid type DOT...

Page 36: ...art 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 M6 1 0 10 10 1 0 7 2 Cylinder head blind plug screw M12 1 0 1 28 2 8 20 Cylinder head...

Page 37: ...8 Air filter joint and air filter case M5 0 8 1 4 0 4 2 9 Air filter element M6 1 0 1 2 0 2 1 4 Exhaust pipe M8 1 25 2 20 2 0 14 Exhaust pipe protector M6 1 0 3 10 1 0 7 2 Silencer M8 1 25 2 30 3 0 2...

Page 38: ...base valve M42 1 5 2 29 2 9 21 Adjuster and damper assembly M12 1 25 2 29 2 9 21 Front fork bleed screw and base valve M5 0 8 2 1 0 1 0 7 Front fork and front fork protector M6 1 0 6 5 0 5 3 6 Lower b...

Page 39: ...M6 1 0 2 7 0 7 5 1 Cable guide and frame M6 1 0 2 7 0 7 5 1 Pivot shaft and nut M16 1 5 1 85 8 5 61 Relay arm and swingarm M14 1 5 1 70 7 0 50 Relay arm and connecting rod M14 1 5 1 80 8 0 58 Connecti...

Page 40: ...ng boss and frame M10 1 25 2 20 2 0 14 Front fender M6 1 0 4 10 1 0 7 2 Rear fender front M6 1 0 2 7 0 7 5 1 Rear fender rear M6 1 0 2 16 1 6 11 Side cover M6 1 0 2 7 0 7 5 1 Seat M8 1 25 2 23 2 3 17...

Page 41: ...ts should be at room temperature A Distance between flats B Outside thread diameter DEFINITION OF UNITS A Nut B Bolt TORQUE SPECIFI CATION Nm m kg ft lb 10 mm 6 mm 6 0 6 4 3 12 mm 8 mm 15 1 5 11 14 mm...

Page 42: ...2 16 LUBRICATION DIAGRAMS LUBRICATION DIAGRAMS 1 Oil filter element 2 Oil pump 3 Drive axle 4 Main axle 5 Intake camshaft 6 Exhaust camshaft 7 Oil tank 8 Oil delivery pipe A To oil tank...

Page 43: ...2 17 LUBRICATION DIAGRAMS 1 Crankshaft 2 Oil filter element 3 Oil tank 4 Oil hose A From oil pump...

Page 44: ...tion sensor lead 7 Hot starter cable 8 Fuel hose 9 Carburetor breather hose 10 Carburetor overflow hose 11 Throttle position sensor lead protector 12 Throttle position sensor cover A Insert the end of...

Page 45: ...ather hose between the radiator and radiator hose 3 E Pass the fuel hose on the out side of throttle position sensor lead F Pass the carburetor breather hoses and overflow hose so that all there hoses...

Page 46: ...10 CDI unit lead coupler 11 Radiator breather hose 12 Hot starter cable protector 13 Rubber cap 14 Throttle position sensor lead 15 Cylinder head breather hose 16 Throttle position sensor lead coupler...

Page 47: ...ortion N Pass each lead under the clamp Locate the CDI magneto lead on the outside of the igni tion coil lead Locate the throttle position sensor lead neutral switch lead CDI magneto lead and ignition...

Page 48: ...ss the throttle cables through the cable guide C Pass the throttle cable over the radiator mounting boss Cross the throttle cable behind the ra diator D Pass the throttle cables on the outside of the...

Page 49: ...directs as shown and lightly touches the projec tion on the brake caliper B Pass the brake hose into the brake hose holders C If the brake hose contacts the spring rear shock absorber correct its twis...

Page 50: ...r B Pass the clutch cable and hot starter cable through the cable guide C Pass the engine stop switch lead behind the CDI unit D Pass the brake hose in front of the number plate E Pass the throttle ca...

Page 51: ...is required by reference to the list below Item After break in Every race about 2 5 hours Every third about 7 5 hours Every fifth about 12 5 hours As re quired Remarks ENGINE OIL Replace Inspect OIL F...

Page 52: ...FT FORK SHIFT CAM GUIDE BAR Inspect Inspect wear ROTOR NUT Retighten EXHAUST PIPE SILENCER PROTECTOR Inspect and retighten Clean Replace Replace fiber When the exhaust sound becomes louder or when a p...

Page 53: ...an and inspect FUEL TANK COCK Clean and inspect BRAKES Adjust lever position and pedal height Lubricate pivot point Check brake disc surface Check fluid level and leakage Retighten brake disc bolts ca...

Page 54: ...lean and lube Lithium base grease Replace bearing TIRE WHEELS Inspect air pressure wheel run out tire wear and spoke loose ness Retighten sprocket bolt Inspect bearings Replace bearings Lubricate Lith...

Page 55: ...slack and alignment Check that the drive chain is lubricated properly P 3 17 18 Wheels Check for excessive wear and tire pressure Check for loose spokes and have no excessive play P 3 20 21 Steering C...

Page 56: ...clean tap water 5 Install Copper washer Coolant drain bolt 6 Fill Radiator Engine To specified level Do not mix more than one type of ethylene glycol antifreeze con taining corrosion inhibitors for al...

Page 57: ...USTING THE CLUTCH CABLE FREE PLAY ADJUSTING THE CLUTCH CABLE FREE PLAY 1 Check Clutch lever free play a Out of specification Adjust 2 Adjust Clutch lever free play Clutch lever free play adjustment st...

Page 58: ...play a is within the specified lim its c Tighten the locknut After adjustment check proper oper ation of hot starter CLEANING THE AIR FILTER ELEMENT Proper air filter maintenance is the biggest key t...

Page 59: ...kcase 4 Install Oil tank cap 5 Start the engine and let it warm up for several minutes 6 Turn off the engine and inspect the oil level once again Wait a few minutes until the oil settles before inspec...

Page 60: ...crew 1 Adjustment steps To optimize the fuel flow at a smaller throttle opening each machine s pilot screw has been individually set at the factory Before adjusting the pilot screw turn it in fully an...

Page 61: ...sing screw 1 Crankshaft end accessing screw 2 O ring 4 Check Valve clearance Out of specification Adjust Checking steps a Turn the crankshaft counterclock wise with a wrench b Align the T D C mark a o...

Page 62: ...intersect shows the new pad number to use Use the new pad number only as a guide when verifying the valve clear ance adjustment f Install the new pads 3 and the valve lifters 4 Apply the engine oil on...

Page 63: ...ASURED CLEARANCE INSTALLED PAD NUMBER STANDARD CLEARANCE Pad number example Pad No 175 1 75 mm Pad No 185 1 85 mm MEASURED CLEARANCE INSTALLED PAD NUMBER 120 125 130 135 140 145 150 155 160 165 170 17...

Page 64: ...eeding procedure when the tiny bubbles in the system have disap peared j Add brake fluid to the level line on the reservoir Check the operation of the brake after bleeding the brake system 3 Install P...

Page 65: ...the brake pads with their pro jections a into the brake caliper re cesses b Temporarily tighten the pad pin at this point i Install the brake caliper 8 and tighten the pad pin 9 j Install the pad pin...

Page 66: ...d level Refer to CHECKING THE BRAKE FLUID LEVEL section 4 Check Brake pedal operation A softy or spongy feeling Bleed brake system Refer to BLEEDING THE HY DRAULIC BRAKE SYSTEM sec tion CHECKING THE R...

Page 67: ...by placing the suitable stand under the en gine 2 Check Drive chain slack a Above the seal guard installation bolt Out of specification Adjust Before checking and or adjusting ro tate the rear wheel t...

Page 68: ...e front fork initial movement feels stiff during a run relieve the front fork internal pressure 1 Elevate the front wheel by placing a suitable stand under the engine 2 Remove the air bleed screw 1 an...

Page 69: ...the locknut and adjust er before adjustment The length of the spring installed changes 1 5 mm 0 06 in per turn of the adjuster Never attempt to turn the adjuster beyond the maximum or minimum setting...

Page 70: ...ximum extent of adjustment The adjuster may be damaged CHECKING THE TIRE PRESSURE 1 Measure Tire pressure Out of specification Adjust Check the tire while it is cold Loose bead stoppers allow the tire...

Page 71: ...k Steering smooth action Turn the handlebar lock to lock Unsmooth action Adjust steer ing ring nut 4 Adjust Steering ring nut Steering ring nut adjustment steps a Remove the number plate b Remove the...

Page 72: ...marks b are in place on both sides Install the handlebar so that the pro jection c of the handlebar upper holder is positioned at the mark on the handlebar as shown Insert the end of the fuel breathe...

Page 73: ...ot 5 Throttle to handlebar contact 6 Drive chain 7 Tube guide cable winding por tion 8 Throttle cable end 9 Clutch cable end 10 Hot starter cable end A Use Yamaha cable lube or equivalent on these are...

Page 74: ...r if necessary 5 Tighten Spark plug Before installing a spark plug clean the gasket surface and plug sur face Finger tighten a the spark plug before torquing to specification b CHECKING THE IGNITION T...

Page 75: ...n adjustment disassembly or reassembly only by reference to this manual It may lead to servicing trouble and mechanical damage SEAT FUEL TANK AND SIDE COVERS REMOVING THE SEAT FUEL TANK AND SIDE COVER...

Page 76: ...lter case REMOVING THE NUMBER PLATE 1 Remove Bolt number plate Number plate 1 The projection a is inserted into the band of the number plate Pull the band off the projection before removal Remove the...

Page 77: ...er Part name Q ty Remarks A Except for USA and CDN Right side cover Refer to SEAT FUEL TANK AND SIDE COVERS section 1 Bolt silencer clamp 1 Only loosening 2 Bolt silencer front 1 3 Bolt silencer rear...

Page 78: ...and also along the si lencer edge b as shown Take care not to allow the fiber out of place when installing the inner pipe INSTALLING THE SILENCER AND EXHAUST PIPE 1 Install Gasket Exhaust pipe 1 Nut...

Page 79: ...ANK AND SIDE COVERS section 1 Radiator guard 2 2 Radiator hose clamp 10 Only loosening 3 Clutch cable holder 1 4 Radiator hose 1 1 5 Left radiator 1 6 Radiator hose 4 1 7 Pipe 1 8 Radiator hose 5 1 9...

Page 80: ...ace INSTALLING THE RADIATOR 1 Install O ring 1 Radiator pipe 1 2 Bolt radiator pipe 3 Apply the lithium soap base grease on the O ring 2 Install Radiator breather hose 1 Radiator hose 2 2 Radiator hos...

Page 81: ...rottle cable cover 1 4 Throttle cable 2 5 Clamp air filter joint 1 Loosen the screw air filter joint 6 Clamp carburetor joint 1 Loosen the screws carburetor joint 7 Hot starter plunger 1 8 Carburetor...

Page 82: ...sing cover 1 3 Screw throttle shaft 1 4 Throttle valve 1 5 Needle holder 1 6 Jet needle 1 7 Accelerator pump cover 1 8 Spring 1 9 Diaphragm accelerator pump 1 10 Float chamber 1 11 Leak jet 1 12 Pilot...

Page 83: ...URETOR 19 Pilot jet 1 20 Starter jet 1 21 Push rod 1 Pull the push rod 22 Throttle shaft assembly 1 23 Push rod link lever assembly 1 24 Pilot air jet 1 25 Cold starter plunger 1 Order Part name Q ty...

Page 84: ...r use a wire CHECKING THE NEEDLE VALVE 1 Inspect Needle valve 1 Valve seat 2 Grooved wear a Replace Dust b Clean Filter c Clogged Clean CHECKING THE THROTTLE VALVE 1 Check Free movement Stick Repair o...

Page 85: ...ing 4 Push rod 5 Tears diaphragm damage Re place Dirt Clean 2 Inspect Throttle shaft 1 Spring 2 Lever 1 3 Spring 1 4 Lever 2 5 Spring 2 6 Dirt Clean ASSEMBLING THE CARBURETOR 1 Install Cold starter pl...

Page 86: ...arbure tor Check the float for smooth move ment 12 Install Pilot screw 1 Spring 2 Washer 3 O ring 4 Note the following installation points a Turn in the pilot screw until it is lightly seated b Turn o...

Page 87: ...ING THE CARBURETOR 1 Install Carburetor joint 1 2 Install Carburetor 1 Install the projection a between the carburetor joint slots 3 Install Hot starter plunger 1 4 Tighten Bolt carburetor joint 1 Bol...

Page 88: ...Order Part name Q ty Remarks Seat and fuel tank Refer to SEAT FUEL TANK AND SIDE COVERS section 1 Spark plug 1 2 Cylinder head breather hose 1 3 Bolt cylinder head cover 2 4 Cylinder head cover 1 5 Cy...

Page 89: ...haft end accessing screw 1 Refer to removal section 3 Timing chain tensioner cap bolt 1 Refer to removal section 4 Timing chain tensioner 1 Refer to removal section 5 Camshaft cap 2 Refer to removal s...

Page 90: ...ap 2 Clip Remove the bolts camshaft cap in a crisscross pattern working from the outside in The bolts camshaft cap must be removed evenly to prevent dam age to the cylinder head cam shafts or camshaft...

Page 91: ...n mechanism cam 1 moves smoothly b Check that the decompression mechanism cam lever pin 2 proj ects from the camshaft CHECKING THE TIMING CHAIN TENSIONER 1 Check While pressing the tensioner rod light...

Page 92: ...e pressing the tensioner rod lightly with fingers use a thin screwdriver and wind the tension er rod up fully clockwise b With the rod fully wound and the chain tensioner UP mark a fac ing upward inst...

Page 93: ...cer Refer to EXHAUST PIPE AND SILENCER section Radiator hose 1 Disconnect at cylinder head side Carburetor Refer to CARBURETOR section Camshaft Refer to CAMSHAFTS section Upper engine bracket Refer to...

Page 94: ...LINDER HEAD 1 Install Dowel pin 1 Cylinder head gasket 2 Timing chain guide exhaust side 3 Cylinder head 4 While pulling up the timing chain in stall the timing chain guide exhaust side and cylinder h...

Page 95: ...e Q ty Remarks Cylinder head Refer to CYLINDER HEAD section 1 Valve lifter 5 Refer to removal section 2 Adjusting pad 5 Refer to removal section 3 Valve cotter 10 Refer to removal section 4 Valve spri...

Page 96: ...to 100 C 212 F a Remove the valve guide using a valve guide remover 1 b Install the new valve guide using a valve guide remover 1 and valve guide installer 2 c After installing the valve guide bore t...

Page 97: ...t lapping the valve seats and valve faces When replacing the valves or valve guides use new valves to lap the valve seats and then replace them with new valves Lapping steps a Apply a coarse lapping c...

Page 98: ...facing upward e Smaller pitch 3 Install Valve cotter While compressing the valve spring with a valve spring compressor 1 in stall the valve cotters 4 To secure the valve cotters onto the valve stem l...

Page 99: ...TON Order Part name Q ty Remarks Cylinder head Refer to CYLINDER HEAD section 1 Bolt cylinder 1 2 Cylinder 1 3 Piston pin clip 2 Refer to removal section 4 Piston pin 1 Refer to removal section 5 Pist...

Page 100: ...eplace the piston and piston rings as set c Measure the piston skirt diameter P with a micrometer a 8 mm 0 31 in from the piston bottom edge d If out of specification replace the piston and piston rin...

Page 101: ...install the piston rings so that the manufacturer s marks or numbers are located on the upper side of the rings Lubricate the piston and piston rings liberally with engine oil 2 Position Top ring 2nd...

Page 102: ...the lithium soap base grease on the O ring 3 Install Cylinder gasket 1 Cylinder 2 Install the cylinder with one hand while compressing the piston rings with the other hand Pass the timing chain 3 thro...

Page 103: ...ER 3 Brake pedal Refer to ENGINE REMOVAL section Clutch cable Disconnect at engine side 1 Clutch cover 1 2 Clutch spring 5 3 Pressure plate 1 4 Push rod 1 1 5 Circlip 1 6 Washer 1 7 Bearing 1 8 Ball 1...

Page 104: ...4 30 CLUTCH 14 Clutch boss 1 Refer to removal section 15 Thrust washer 1 16 Primary driven gear 1 17 Spacer 1 18 Washer 1 19 Push lever shaft 1 Order Part name Q ty Remarks...

Page 105: ...sure at all four points CHECKING THE CLUTCH PLATES 1 Measure Clutch plate warpage Out of specification Replace clutch plate as a set Use a surface plate 1 and thick ness gauge 2 CHECKING THE PUSH LEVE...

Page 106: ...th a friction plate Apply the engine oil on the friction plates and clutch plates 5 Install Bearing 1 Washer 2 Circlip 3 To push rod 1 4 Apply the engine oil on the bearing and washer 6 Install Push r...

Page 107: ...the coolant Refer to CHANGING THE COOLANT sec tion in the CHAPTER 3 Radiator hose 3 Disconnect at water pump side Exhaust pipe Refer to EXHAUST PIPE AND SILENCER section Brake pedal Refer to ENGINE RE...

Page 108: ...ER ELEMENT AND WATER PUMP 9 Washer 1 Refer to removal section 10 Impeller shaft 1 Refer to removal section 11 Oil seal 2 Refer to removal section 12 Bearing 1 Refer to removal section Order Part name...

Page 109: ...PE 1 Inspect Oil delivery pipe 1 Bend damage Replace Clogged Blow CHECKING THE IMPELLER SHAFT 1 Inspect Impeller shaft 1 Bend wear damage Replace Fur deposits Clean CHECKING THE IMPELLER SHAFT GEAR 1...

Page 110: ...ller shaft gear 3 with primary drive gear 4 Tighten the bolts in stage using a crisscross pattern INSTALLING THE KICKSTARTER CRANK 1 Install Kickstarter crank 1 Washer Bolt kickstarter crank Install s...

Page 111: ...ring 2 Install Water pump housing 1 Bolt water pump housing 2 INSTALLING THE OIL FILTER ELEMENT 1 Install Oil filter element 1 O ring 2 Oil filter element cover 3 Bolt oil filter element cover Apply...

Page 112: ...IL FILTER ELEMENT AND WA TER PUMP section Stator Refer to CDI MAGNETO section 1 Nut primary drive gear 1 Refer to removal section 2 Nut balancer shaft driven gear 1 Refer to removal section 3 Lock was...

Page 113: ...the center a of the balancer shaft weight along the line connect ing the centers of the crankshaft and balancer shaft 2 Install Balancer shaft driven gear 1 Install the balancer shaft driven gear ont...

Page 114: ...ankcase cover Refer to OIL FILTER ELEMENT AND WA TER PUMP section 1 Circlip 1 2 Washer 1 3 Oil pump drive gear 1 4 Oil pump assembly 1 5 Outer rotor 2 1 6 Circlip 1 7 Inner rotor 2 1 8 Dowel pin 1 9 O...

Page 115: ...THE OIL TANK Order Part name Q ty Remarks Drain the engine oil Refer to CHANGING THE ENGINE OIL section in the CHAPTER 3 1 Oil hose 2 1 2 Oil hose 1 1 3 Dowel pin 2 4 Oil tank breather hose 1 5 Oil t...

Page 116: ...tor 1 1 Apply the engine oil on the outer rotor 1 3 Install Oil pump cover 1 Screw oil pump cover 2 Dowel pin 3 Inner rotor 2 4 Circlip 5 Apply the engine oil on the inner ro tor 2 Fit the dowel pin i...

Page 117: ...breather hose 2 Clamp 3 Install the clamp so that it does not contact the oil tank Insert the oil tank breather hose so that its end a comes where the oil tank pipe begins to bend Install the clamp 3...

Page 118: ...ection 1 Kick idle gear 1 2 Kick shaft assembly 1 Refer to removal section 3 Spring guide 1 4 Torsion spring 1 5 Ratchet wheel 1 6 Kick gear 1 7 Kick shaft 1 8 Washer 1 9 Shift pedal 1 10 Shift shaft...

Page 119: ...4 45 KICK SHAFT AND SHIFT SHAFT 17 Pawl 2 18 Pawl pin 2 19 Spring 2 20 Bolt stopper lever 1 21 Stopper lever 1 22 Torsion spring 1 23 Segment 1 Refer to removal section Order Part name Q ty Remarks...

Page 120: ...move ment Unsmooth movement Replace Kick shaft 2 Wear damage Replace Spring 3 Broken Replace CHECKING THE KICK GEAR KICK IDLE GEAR AND RATCHET WHEEL 1 Inspect Kick gear 1 Kick idle gear 2 Ratchet whee...

Page 121: ...e roller and shift shaft 2 Install Shift pedal 1 Bolt shift pedal 2 Install with the punch mark a on the shift pedal in alignment with the punch mark b on the shift shaft INSTALLING THE KICK SHAFT ASS...

Page 122: ...lide the kick shaft assembly into the crankcase and make sure the kick shaft stopper a fits into the kick shaft ratchet wheel guide 5 Hook Torsion spring 1 Turn the torsion spring clockwise and hook i...

Page 123: ...Seat and fuel tank Refer to SEAT FUEL TANK AND SIDE COVERS section Disconnect the CDI magneto lead Shift pedal Refer to KICK SHAFT AND SHIFT SHAFT section 1 Left crankcase cover 1 2 Nut rotor 1 Refer...

Page 124: ...portions of the crankshaft and rotor When installing the woodruff key make sure that its flat surface a is in parallel with the crankshaft center line b When installing the rotor align the keyway c o...

Page 125: ...ion Exhaust pipe and silencer Refer to EXHAUST PIPE AND SILENCER section Clutch cable Disconnect at the engine side Radiator Refer to RADIATOR section Shift pedal Refer to KICK SHAFT AND SHIFT SHAFT s...

Page 126: ...5 Lock washer 1 Refer to removal section 6 Drive sprocket 1 Refer to removal section 7 Clip 1 8 Bolt brake pedal 1 9 Brake pedal 1 10 Upper engine bracket 2 11 Front engine bracket 2 12 Engine mounti...

Page 127: ...Pivot shaft 2 Engine mounting bolt lower 3 Front engine bracket 4 Bolt front engine bracket 5 Patch 6 Engine mounting bolt front 7 Upper engine bracket 8 Bolt upper engine bracket 9 Engine mounting b...

Page 128: ...e chain sprocket guide 1 Drive chain sprocket cover 2 Bolt drive chain sprocket cover 3 INSTALLING THE NEUTRAL SWITCH 1 Install Spring 1 Pin 2 O ring 3 Neutral switch 4 Screw neutral switch 5 Apply th...

Page 129: ...KICK SHAFT AND SHIFT SHAFT section Stator Refer to CDI MAGNETO section Balancer shaft Refer to BALANCER section 1 Timing chain guide intake side 1 2 Timing chain 1 3 Oil delivery pipe 2 1 4 Bolt L 45...

Page 130: ...4 56 CRANKCASE AND CRANKSHAFT 10 Left crankcase 1 Refer to removal section 11 Oil strainer 1 12 Crankshaft 1 Refer to removal section Order Part name Q ty Remarks...

Page 131: ...RANKCASE BEARING Order Part name Q ty Remarks Transmission Refer to TRANSMISSION SHIFT CAM AND SHIFT FORK section Shift cam and shift fork Refer to TRANSMISSION SHIFT CAM AND SHIFT FORK section 1 Oil...

Page 132: ...Do not use a hammer to drive out the crankshaft REMOVING THE CRANKCASE BEARING 1 Remove Bearing 1 Remove the bearing from the crankcase by pressing its inner race Do not use the removed bearing CHECKI...

Page 133: ...center with one hand while turning the nut of the installing tool with the other Operate the installing tool un til the crankshaft bottoms against the bearing Before installing the crankshaft clean th...

Page 134: ...rankcase tightening bolts in stage using a crisscross pat tern 7 Install Oil delivery pipe 2 1 O ring 2 Bolt oil delivery pipe 2 3 Apply the lithium soap base grease on the Orings 8 Install Timing cha...

Page 135: ...Engine Refer to ENGINE REMOVAL section Separate the crankcase Refer to CRANKCASE AND CRANK SHAFT section 1 Main axle 1 Refer to removal section 2 Drive axle 1 Refer to removal section 3 Shift cam 1 R...

Page 136: ...eplace CHECKING THE 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 oper...

Page 137: ...ase pay careful attention to the crankcase oil seal lip 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 Apply the engine oil on the shift fork groo...

Page 138: ...ertake inspection adjustment disassembly or reassembly only by reference to this manual It may lead to servicing trouble and mechanical damage FRONT WHEEL AND REAR WHEEL REMOVING THE FRONT WHEEL Order...

Page 139: ...hine by placing the suitable stand under the engine Refer to HANDLING NOTE 1 Nut rear wheel axle 1 2 Rear wheel axle 1 3 Drive chain puller 2 4 Rear wheel 1 Refer to removal section 5 Collar 2 6 Rear...

Page 140: ...ake disc deflection only rear brake disc Use the dial gauge 1 Out of specification Inspect wheel runout If wheel runout is in good condi tion replace the brake disc 2 Measure Brake disc thickness a Ou...

Page 141: ...al 5 Apply the lithium soap base grease on the bearing and oil seal lip when installing Install the bearing with seal facing outward Use a socket that matches the out side diameter of the race of the...

Page 142: ...l axle 2 Install the left drive chain puller and insert the wheel axle from left side Apply the lithium soap base grease on the wheel axle 8 Install Right drive chain puller 1 Washer 2 Nut wheel axle...

Page 143: ...and under the engine Refer to HANDLING NOTE Drain the brake fluid Refer to removal section 1 Brake hose holder protector 2 2 Union bolt 2 3 Brake hose 1 4 Pad pin plug 1 Remove when loosening the pad...

Page 144: ...e Refer to HANDLING NOTE Rear wheel Refer to FRONT WHEEL AND REAR WHEEL section Drain the brake fluid Refer to removal section 1 Brake pedal 1 2 Brake master cylinder 1 3 Brake hose holder 2 4 Union b...

Page 145: ...der Part name Q ty Remarks A Front B Rear A B 1 Pad pin 1 1 2 Brake pad 2 2 3 Pad support 1 1 4 Brake caliper piston 2 1 Refer to removal section 5 Brake caliper piston dust seal 2 1 Refer to removal...

Page 146: ...INDER Order Part name Q ty Remarks A Front B Rear 1 Brake master cylinder cap 1 2 Diaphragm 1 3 Reservoir float 1 4 Push rod Front 1 5 Brake master cylinder boot 1 6 Circlip 1 Use a long nose circlip...

Page 147: ...ion when expelling piston from cylinder Never attempt to pry out piston Caliper piston removal steps a Insert a piece of rag into the brake caliper to lock one brake caliper b Carefully force the pist...

Page 148: ...caliper piston dust seals whenever a caliper is disassembled INSTALLING THE BRAKE CALIPER PISTON 1 Clean Brake caliper Brake caliper piston seal Brake caliper piston dust seal Brake caliper piston Cl...

Page 149: ...der cup sec ondary 2 To brake master cylinder piston 3 Apply the brake fluid on the brake master cylinder cup After installing cylinder cup should be installed as shown di rection Wrong installation c...

Page 150: ...pipe portion a directs as shown and lightly touches the projection b on the brake master cylinder 2 Install Brake master cylinder 1 Bolt brake master cylinder 2 3 Install Spring 1 Brake pedal 2 O ring...

Page 151: ...l Brake hose holder 1 Screw brake hose holder 2 After installing the brake hose holders make sure the brake hose does not contact the spring rear shock absorber If it does correct its twist FILLING TH...

Page 152: ...oat front brake Diaphragm Brake master cylinder cap 1 Screw brake master cylinder cap 2 After installation while pulling the brake lever in or pushing down on the brake pedal check whether there is an...

Page 153: ...to FRONT WHEEL AND REAR WHEEL section Front brake caliper Refer to FRONT BRAKE AND REAR BRAKE section Number plate Refer to SEAT FUEL TANK AND SIDE COVERS section in the CHAPTER 4 1 Protector 1 2 Pin...

Page 154: ...ing 1 Refer to removal section 5 Inner tube 1 Refer to removal section 6 Outer tube 1 7 Piston metal 1 8 Slide metal 1 9 Oil seal washer 1 10 Oil seal 1 11 Base valve 1 Drain the fork oil Refer to rem...

Page 155: ...2 REMOVING THE ADJUSTER 1 Drain the outer tube of its front fork oil at its top 2 Loosen Adjuster 1 3 Remove Adjuster 1 While compressing the inner tube 2 set the cap bolt ring wrench 4 between the i...

Page 156: ...nds Out of specification Replace Use the dial gauge 1 The bending value is shown by one half of the dial gauge reading Do not attempt to straighten a bent inner tube as this may dangerous ly weaken th...

Page 157: ...he damper as sembly 1 slowly up and down more than 10 times to distribute the fork oil 12 While protecting the damper as sembly 1 with a rag and com pressing fully allow excessive oil to overflow on t...

Page 158: ...se on the inner tube 22 Check Inner tube smooth movement Tightness binding rough spots Repeat the steps 15 to 21 23 Measure Distance a Out of specification Turn into the locknut 24 Install Collar 1 Fo...

Page 159: ...r 1 To inner tube 31 Fill Front fork oil 1 From outer tube top Never fail to make the oil amount adjustment between the maximum and minimum amount and always adjust each front fork to the same setting...

Page 160: ...torqued too much it may cause the front fork to mal function 5 Install Protector 1 Bolt protector 2 6 Adjust Rebound damping force Turn in the damping adjuster 1 fin ger tight and then turn out to the...

Page 161: ...er side 4 Clutch lever holder 1 5 Engine stop switch 1 6 Brake master cylinder 1 Refer to removal section 7 Throttle cable cap 1 8 Throttle cable 1 pulled 1 Disconnect at the throttle side 9 Throttle...

Page 162: ...s tance a from the mounting bolt center faces forward And install it in the hole b in the rear of the up per bracket Apply the lithium soap base grease on the thread of the handlebar low er holder Cha...

Page 163: ...base grease on the throttle cable end and tube guide cable winding portion 8 Install Throttle cable cap 1 Screw throttle cable cap 2 After tightening the screws check that the throttle grip 3 moves s...

Page 164: ...ddle of the clutch lever hold er 12 Install Clutch cable 1 Hot starter cable 2 Apply the lithium soap base grease on the clutch cable end and hot start er cable end 13 Adjust Clutch lever free play Re...

Page 165: ...the engine Refer to HANDLING NOTE Number plate Refer to SEAT FUEL TANK AND SIDE COVERS section in the CHAPTER 4 Handlebar Refer to HANDLEBAR section 1 Front fender 1 2 Steering stem nut 1 3 Front fork...

Page 166: ...as a set Install the bearing in the bearing races Spin the bearings by hand If the bearings hang up or are not smooth in their operation in the bearing races replace bearings and bearing races as a s...

Page 167: ...act surface of the steering stem nut when installing 9 After tightening the nut check the steering for smooth movement If not adjust the steering by loosen ing the steering ring nut little by lit tle...

Page 168: ...NG NOTE Brake hose holder Refer to FRONT BRAKE AND REAR BRAKE section Rear brake caliper Refer to FRONT BRAKE AND REAR BRAKE section Bolt brake pedal Shift the brake pedal backward Drive chain 1 Drive...

Page 169: ...SWINGARM DISASSEMBLING THE SWINGARM Order Part name Q ty Remarks 1 Relay arm 1 2 Connecting rod 1 3 Collar 2 4 Oil seal 2 5 Thrust bearing 2 6 Bushing 2 7 Oil seal 8 8 Bearing 10 Refer to removal sec...

Page 170: ...1 Install Bearing 1 Oil seal 2 To swingarm Apply the molybdenum disulfide grease on the bearing when install ing Install the bearing by pressing it on the side having the manufacture s marks or numbe...

Page 171: ...lybdenum disulfide grease on the bolt circumference and threaded portion Do not tighten the nut yet 6 Install Swingarm 1 Pivot shaft 2 Apply the molybdenum disulfide grease on the pivot shaft Insert t...

Page 172: ...Drive chain support 1 Drive chain support cover 2 Bolt drive chain support L 50 mm 1 97 in 3 Nut drive chain support 4 Bolt drive chain support cover L 10 mm 0 39 in 5 Nut relay arm 70 Nm 7 0 m kg 50...

Page 173: ...in the CHAPTER 4 Silencer Refer to EXHAUST PIPE AND SILENCER section in the CHAPTER 4 1 Clamp air filter joint 1 Only loosening 2 Rear frame 1 3 Bolt rear shock absorber relay arm 1 Hold the swingarm...

Page 174: ...e bottom of the nitro gen gas tank It is very danger ous to remove the plug When scrapping the rear shock absorber follow the instruc tions on disposal NOTES ON DISPOSAL YAMAHA DEALERS ONLY Before dis...

Page 175: ...to ADJUSTING THE REAR SHOCK ABSORBER SPRING PRELOAD section in the CHAPTER 3 4 Tighten Locknut 1 INSTALLING THE REAR SHOCK ABSORBER 1 Install Dust seal 1 O ring 2 Collar 3 Apply the molybdenum disulfi...

Page 176: ...Rear frame 1 Bolt rear frame upper 2 Bolt rear frame lower 3 7 Tighten Bolt air filter joint 1 Bolt rear frame upper 32 Nm 3 2 m kg 23 ft lb Bolt rear frame lower 32 Nm 3 2 m kg 23 ft lb Bolt air fil...

Page 177: ...vicing of Yamaha motorcycles e g Yamaha dealers service engineers etc Those who have little knowledge and skill concerning servicing are request ed not to undertake inspection adjustment disassembly o...

Page 178: ...tion sensor 3 Neutral switch 4 CDI magneto 5 Ignition coil 6 Spark plug 7 CDI unit COLOR CODE B Black Br Brown G Green L Blue O Orange P Pink R Red Sb Sky blue W White Y Yellow B L Black Blue B W Blac...

Page 179: ...following special tools in this inspection Spark gap test Spark Clean or replace spark plug No spark Check entire ignition system for connection couplers leads and ignition coil No good Repair or rep...

Page 180: ...ile it is freed Re place Set the tester selection position to 1 CHECKING THE IGNITION COIL 1 Remove the ignition coil cap 2 Inspect Primary coil resistance Out of specification Replace 3 Inspect Secon...

Page 181: ...osition to 1 CHECKING THE CDI UNIT Check all electrical components If no fault is found replace the CDI unit Then check the electrical compo nents again Tester lead Brown lead 1 Tester lead Green lead...

Page 182: ...IGNITION SYSTEM section Use the following special tools in this inspection Check entire ignition system for connection No good Repair or replace OK Check throttle position sensor Throttle position sen...

Page 183: ...position sensor using the T25 bit 3 Replace Throttle position sensor 4 Install Throttle position sensor 1 Screw throttle position sensor 2 Align the slot a in the throttle posi tion sensor with the pr...

Page 184: ...tor 11 Stop the engine 12 Remove the carburetor 13 Tighten Screw throttle position sensor 1 Tighten the screw throttle position sensor using the T25 bit 14 Install the carburetor CHECKING THE THROTTLE...

Page 185: ...ssarily Otherwise too much fuel may be discharged starting may become difficult or the engine may not run well After installing the carburetor check that the throttle operates correctly and opens and...

Page 186: ...ll not pick up speed quickly Step down the jet needle clip by one groove and move up the nee dle to enrich the mixture Effects of changing the jet needle groove position reference A Idle B Fully open...

Page 187: ...MX 14943 44 182 4MX 14943 94 STD 180 4MX 14943 43 178 4MX 14943 93 175 4MX 14943 42 172 4MX 14943 92 Lean 170 4MX 14943 41 Pilot jet Size Part number Rich 50 4MX 14948 07 48 4MX 14948 06 STD 45 4MX 14...

Page 188: ...ixture Increase main jet calibration no Gradual ly Discoloration of spark plug If tan color it is in good condition If cannot be corrected Clogged float valve seat Clogged fuel hose Clogged fuel cock...

Page 189: ...a larger diameter Raise jet needle clip position 1 groove up Poor response in the low to in termediate speeds Raise jet needle clip position If this has no effect lower the jet needle clip position Po...

Page 190: ...condi tion the tire pressure should be higher to prevent a flat tire FRONT FORK SETTING The front fork setting should be made depending on the rider s feeling of an actual run and the circuit conditi...

Page 191: ...ension setting includes the following two factors 1 Setting of spring preload Change the set length of the spring Change the spring 2 Setting of damping force Change the rebound damping Change the com...

Page 192: ...ceed the standard as it may result in faulty performance Never use one whose overall length is greater than standard REAR SHOCK ABSORBER SETTING PARTS Rear shock spring 1 Equal pitch steel spring The...

Page 193: ...ire range bottoming out Compression damping Turn adjuster clockwise about 2 clicks to in crease damping Oil amount Increase oil amount by about 5 10 cm3 0 2 0 4 Imp oz 0 2 0 3 US oz Spring Replace wit...

Page 194: ...avy and dragging Rebound damping Turn adjuster counterclockwise about 2 clicks to decrease damping Spring Replace with soft spring Poor road gripping Rebound damping Turn adjuster counterclockwise abo...

Page 195: ......

Page 196: ...PRINTED IN JAPAN E PRINTED ON RECYCLED PAPER YAMAHA MOTOR CO LTD 2500 SHINGAI IWATA SHIZUOKA JAPAN...

Search results

Summary of Contents for YZ250F(Z)

Reviews:

Related manuals for YZ250F(Z)

Brands by name

Popular brands

Yamaha YZ250F(Z), Owner'S Service Manual

Search results

Summary of Contents for YZ250F(Z)

Reviews:

Related manuals for YZ250F(Z)

Brands by name

Popular brands