2010 YAMAHA YZ250F steering wheel

CONTENTS
CHAPTER 1GENERAL
INFORMATION
LOCATION OF
IMPORTANT LABELS ..... 1-1
DESCRIPTION ................. 1-5
CONSUMER
INFORMATION................. 1-6
INCLUDED PARTS .......... 1-6
IMPORTANT
INFORMATION................. 1-6
CHECKING OF
CONNECTION .................. 1-7
SPECIAL TOOLS ............. 1-8
CONTROL
FUNCTIONS ................... 1-12
STARTING AND
BREAK-IN ...................... 1-13
TORQUE-CHECK
POINTS........................... 1-15
CLEANING AND
STORAGE ...................... 1-16
CHAPTER 2
SPECIFICATIONS
GENERAL
SPECIFICATIONS ............ 2-1
MAINTENANCE
SPECIFICATIONS ............ 2-3
TIGHTENING
TORQUES ...................... 2-10
LUBRICATION
DIAGRAMS .................... 2-16
CABLE ROUTING
DIAGRAM ....................... 2-18
CHAPTER 3 REGULAR
INSPECTION AND ADJUSTMENTS
MAINTENANCE
INTERVALS ...................... 3-1
PRE-OPERATION
INSPECTION AND
MAINTENANCE................ 3-5
ENGINE ............................ 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
SPRINGS ........................ 4-21
CYLINDER AND
PISTON ........................... 4-25
CLUTCH ......................... 4-29
OIL FILTER ELEMENT
AND WATER PUMP ....... 4-33
BALANCER .................... 4-38
OIL PUMP ....................... 4-40
KICK SHAFT AND
SHIFT SHAFT ................. 4-44
CDI MAGNETO............... 4-49
ENGINE REMOVAL ....... 4-51
CRANKCASE AND
CRANKSHAFT ............... 4-55
TRANSMISSION,
SHIFT CAM AND
SHIFT FORK................... 4-61
CHAPTER 5CHASSIS
FRONT WHEEL AND
REAR WHEEL ..................5-1
FRONT BRAKE AND
REAR BRAKE ..................5-6
FRONT FORK .................5-16
HANDLEBAR..................5-24
STEERING ......................5-28
SWINGARM ....................5-31
REAR SHOCK
ABSORBER ....................5-36
CHAPTER 6
ELECTRICAL
ELECTRICAL
COMPONENTS AND
WIRING DIAGRAM ...........6-2
IGNITION SYSTEM...........6-3
THROTTLE POSITION
SENSOR SYSTEM ...........6-6
CHAPTER 7 TUNING
ENGINE.............................7-1
CHASSIS ..........................7-6

1-15
TORQUE-CHECK POINTS
TORQUE-CHECK POINTS
Concerning the tightening torque, refer to "TIGHTENING TORQUES" section in the CHAPTER 2.
Frame constructionFrame to rear frame
Combined seat and fuel tank Fuel tank to frame
Exhaust system Silencer to rear frame
Engine mounting Frame to engine
Engine bracket to engine
Engine bracket to frame
Steering Steering stem to handlebar Steering stem to frame
Steering stem to upper bracket
Upper bracket to handlebar
Suspension Front Steering stem to front forkFront fork to upper bracket
Front fork to lower bracket
Rear For link 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
Wheel Installation of wheel Front Tightening of wheel axle
Tightening of axle holder
Rear Tightening of wheel axle Wheel to rear wheel sprocket
Brake Front Brake caliper to front fork
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to handlebar
Tightening of bleed screw
Tightening of brake hose holder
Rear Brake pedal to frame Brake disc to wheel
Tightening of union bolt
Brake master cylinder to frame
Tightening of bleed screw
Tightening of brake hose holder
Fuel system Fuel tank to fuel cock
Lubrication system Tightening of oil hose clamp

2-12
TIGHTENING TORQUES
CHASSIS
△- marked portion shall be checked for torque ti ghtening after break-in or before each race.
Drive sprocket M18 × 1.0 1 75 7.5 54
Drive axle oil seal stopper M6 × 1.0 2 10 1.0 7.2
Segment M8 × 1.25 1 30 3.0 22
Shift guide M6 × 1.0 2 10 1.0 7.2
Stopper lever M6 × 1.0 1 10 1.0 7.2
Shift pedal M6 × 1.0 1 12 1.2 8.7
Part to be tightened
Thread size Q'tyTightening torque
Nm m•kg ft•lb
Part to be tightened Thread size Q'tyTightening torque
Nm m•kg ft•lb
△ Upper bracket and outer tube M8 × 1.25 4 21 2.1 15
△ Lower bracket and outer tube M8 × 1.25 4 21 2.1 15
△ Upper bracket and steeri ng stem M24 × 1.0 1 145 14.5 105
△ Handlebar upper holder and handlebar lower holder M8 × 1.25 4 28 2.8 20
△ Handlebar lower holder and upper bracket M10 × 1.25 2 34 3.4 25
△ Steering stem and steering ring nut M28 × 1.0 1Refer to TIP.
Front fork and damper assembly M51 × 1.5 2 30 3.0 22
Front fork and adjuster M22 × 1.25 2 55 5.5 40
Damper assembly and 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 bracket and brake hose guide M6 × 1.0 1 9 0.9 6.5
△ Front fork protector and brake hose holder M6 × 1.0 2 8 0.8 5.8
Throttle grip cap M5 × 0.8 2 4 0.4 2.9
△ Front brake master cylinder M6 × 1.0 2 9 0.9 6.5
Brake lever mounting bolt M6 × 1.0 1 6 0.6 4.3
Brake lever mounting nut M6 × 1.0 1 6 0.6 4.3
Brake lever position locknut M6 × 1.0 1 5 0.5 3.6
Clutch lever holder M6 × 1.0 2 5 0.5 3.6
Clutch lever mounting nut M6 × 1.0 1 4 0.4 2.9
Clutch lever position lock nut M5 × 0.8 1 5 0.5 3.6
Hot starter lever holder M5 × 0.8 2 4 0.4 2.9
Front brake master cylinder cap M4 × 0.7 2 2 0.2 1.4
△ Front brake hose union bolt M10 × 1.25 2 30 3.0 22
△ Front brake caliper M8 × 1.25 2 28 2.8 20
Pad pin plug M10 × 1.0 2 3 0.3 2.2
△ Front brake caliper and pad pin M10 × 1.0 1 18 1.8 13
△ Rear brake caliper and pad pin M10 × 1.0 1 18 1.8 13
△ Brake caliper and bleed screw M8 × 1.25 2 6 0.6 4.3
△ Front wheel axle and axle nut M16 × 1.5 1 105 10.5 75
△ Front wheel axle holder M8 × 1.25 4 21 2.1 15

3-4
MAINTENANCE INTERVALS
REAR SHOCK ABSORBERInspect and adjust ●●
Lube ●(After
rain
ride) ●Molybdenum disulfide grease
Replace spring seat ●Every one year
Retighten ●●
DRIVE CHAIN GUIDE AND
ROLLERS Inspect ●●
SWINGARM Inspect, lube and retighten ●● Molybdenum disulfide grease
RELAY ARM, CONNECTING
ROD Inspect, lube and retighten ●● Molybdenum disulfide grease
STEERING HEAD Inspect free play and retighten ●●
Clean 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 ●Lithium base grease
THROTTLE, CONTROL CABLE Check routing and connection ●●
Lubricate ●● Yamaha cable lube or SAE 10W-40
motor oil
Inspect and clean (throttle ca-
ble) ●●
Inspect dirt and wear on the throttle
cable on the carburetor side.
HOT STARTER, CLUTCH LEVER Inspect free play ●
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

3-5
PRE-OPERATION INSPECTION AND MAINTENANCE
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 points.
GENERAL INSPECTION AND MAINTENANCE
Item RoutinePage
Coolant Check that coolant is filled up to the radiator cap. Check the cool-
ing system for leakage. P.3-6 – 7
Fuel Check that a fresh gasoline is filled in the fuel tank. Check the fuel
line for leakage. P.1-13
Engine oil Check that the oil level is correct. Check the crankcase and oil line
for leakage.
P.3-9 – 10
Gear shifter and clutch Check that gears can be shifted correctly in order and that the
clutch operates smoothly. P.3-7
Throttle grip/Housing Check that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary. P.3-7 – 8
Brakes Check the play of front brake and ef fect of front and rear brake. P.3-14 – 16
Drive chain Check drive chain slack and alignment. Check that the drive chain
is lubricated properly.
P.3-17 – 18
Wheels Check for excessive wear and ti
re pressure. Check for loose
spokes and have no excessive play. P.3-20 – 21
Steering Check that the handlebar can be turned smoothly and have no ex-
cessive play. P.3-21 – 22
Front forks and rear shock
absorber Check that they operate smooth
ly and there is no oil leakage.
P.3-18 – 20
Cables (wires) Check that the clutch and throttle cables move smoothly. Check
that they are not caught when the handlebars are turned or when
the front forks travel up and down.
—
Exhaust pipe Check that the exhaust pipe is tightly mounted and has no cracks. P.4-3 – 4
Rear wheel sprocket Check that the rear whee l sprocket tightening bolt is not loose.P.3-17
Lubrication Check for smooth operation. Lubricate if necessary. P.3-23
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-15
Lead connectors Check that the CDI magneto, CDI
unit, and ignition coil are con-
nected tightly. P.1-7
Settings Is the machine set suitably for the
condition of the racing course
and weather or by taking into account the results of test runs be-
fore racing? Are inspection and maintenance completely done? P.7-1 – 10

3-21
CHASSIS
CHECKING AND TIGHTENING THE
SPOKES
The following procedure applies to all
of the spokes.
1. Check:• SpokesBend/damage →Replace.
Loose spoke →Retighten.
Tap the spokes with a screw-
driver.
A tight spoke will emit a clear, ringing
tone; a loose spoke will sound flat.
2. Tighten: • Spokes
(with a spoke nipple wrench "1")
Be sure to retighten these spokes be-
fore and after break-in.
CHECKING THE WHEELS
1. Inspect:• Wheel runout
Elevate the wheel and turn it.
Abnormal runout → Replace. 2. Inspect:
• Bearing free playExist play →Replace.
CHECKING AND ADJUSTING THE
STEERING HEAD
1. Place a stand under the engine to raise the front wheel off the
ground. WARNING! Securely
support the vehicle so that
there is no danger of it falling
over.
2. Check: • Steering stemGrasp the bottom of the forks and
gently rock the fork assembly
back and forth.
Free play →Adjust steering head.
3. Check: • Steering smooth actionTurn 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 handlebar and upper
bracket. c. Loosen the steering ring nut "1"
using the steering nut wrench "2".
d. Tighten the steering ring nut "3" using steering nut wrench "4".
• Apply the lithium soap base grease on the thread of the steering stem.
• Set the torque wrench to the steer-
ing nut wrench so that they form a
right angle.
e. Loosen the steering ring nut one turn.
f. Retighten the steering ring nut us- ing the steering nut wrench.
Avoid over-tightening.
g. Check the steering stem by turn-ing it lock to lock. If there is any
binding, remove the steering stem
assembly and inspect the steer-
ing bearings.
Spoke nipple wrench:
YM-01521/90980-01521
Spokes: 3 Nm (0.3 m•kg, 2.2
ft•lb)
Steering nut wrench:YU-33975/90890-01403
Steering nut wrench: YU-33975/90890-01403
Steering ring nut (initial
tightening): 38 Nm (3.8 m•kg, 27
ft•lb)
Steering ring nut (final
tightening): 7 Nm (0.7 m•kg, 5.1
ft•lb)