2002 YAMAHA WR 250F steering

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 points.
GENERAL INSPECTION AND MAINTENANCE
Item Routine Page
CoolantCheck that coolant is filled up to the radiator cap.
Check that the coolant level is correct in the coolant reservoir.
Check the cooling system for leakage.P.3-5 ~ 9
FuelCheck that a fresh gasoline is filled in the fuel tank. Check the
fuel line for leakage.P.1-14
Engine oilCheck that the oil level is correct. Check the crankcase and
frame oil line for leakage.P.3-14 ~ 18
Gear shifter and clutchCheck that gears can be shifted correctly in order and that the
clutch operates smoothly.P.3-9
Throttle grip/HousingCheck that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary.P.3-10 ~ 11
Brakes Check the play of front brake and effect of front and rear brake. P.3-26 ~ 32
Drive chainCheck drive chain slack and alignment. Check that the drive
chain is lubricated properly.P.3-33 ~ 35
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-43 ~ 44
SteeringCheck that the handlebar can be turned smoothly and have no
excessive play.P.3-44 ~ 45
Front forks and rear shock
absorberCheck that they operate smoothly and there is no oil leakage. P.3-35 ~ 42
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 pipeCheck that the exhaust pipe is tightly mounted and has no
cracks.P.4-2
Rear wheel sprocket Check that the rear wheel sprocket tightening bolt is not loose. P.3-33
Lubrication Check for smooth operation. Lubricate if necessary. P.3-46
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-18
Lead connectorsCheck that the CDI magneto, CDI unit, and ignition coil are con-
nected tightly.P.1-6
SettingsIs the machine set suitably for the condition of the racing course
and weather or by taking into account the results of test runs
before racing? Are inspection and maintenance completely
done?P.7-1 ~ 23

3 - 44
INSP
ADJ
STEERING HEAD INSPECTION AND ADJUSTMENT
2. Inspect:
Bearing free play
Exist play → Replace.
STEERING HEAD INSPECTION AND
ADJUSTMENT
1. Elevate the front wheel by placing a suit-
able stand under the engine.
2. Check:
Steering stem
Grasp the bottom of the forks and gen-
tly rock the fork assembly back and
forth.
Free play → Adjust steering head.
3. Check:
Steering smooth action
Turn the handlebar lock to lock.
Unsmooth action → Adjust steering ring
nut.
4. Adjust:
Steering ring nut
Steering ring nut adjustment steps:
Remove the headlight.
Remove the handlebar and upper bracket.
Loosen the steering ring nut 1 using the
steering nut wrench 2.
Steering nut wrench:
YU-33975/90890-01403

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INSP
ADJ
STEERING HEAD INSPECTION AND ADJUSTMENT
Tighten the steering ring nut 3 using
steering nut wrench 4.
NOTE:
Set the torque wrench to the steering nut
wrench so that they form a right angle.
Steering nut wrench:
YU-33975/90890-01403
T R..
Steering ring nut (initial tighten-
ing):
38 Nm (3.8 m • kg, 27 ft • lb)
Loosen the steering ring nut one turn.
Retighten the steering ring nut using the
steering nut wrench.
WARNING
Avoid over-tightening.
T R..
Steering ring nut (final tighten-
ing):
7 Nm (0.7 m • kg, 5.1 ft • lb)
Check the steering stem by turning it lock
to lock. If there is any binding, remove the
steering stem assembly and inspect the
steering bearings.
Install the upper bracket 5, steering stem
nut 6, handlebar 7, handlebar holder 8
and headlight 9.
NOTE:
The upper handlebar holder should be
installed with the punched mark a for-
ward.
Insert the end of fuel breather hose 0 into
the hole of the steering stem.
CAUTION:
First tighten the bolts on the front side of
the handlebar holder, and then tighten
the bolts on the rear side.
T R..
Steering stem nut:
145 Nm (14.5 m • kg, 105 ft • lb)
Handlebar upper holder:
28 Nm (2.8 m • kg, 20 ft • lb)
Pinch bolt (upper bracket):
23 Nm (2.3 m • kg, 17 ft • lb)
Headlight:
7 Nm (0.7 m • kg, 5.1 ft • lb)

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CHAS
11. Install:
Clutch cable 1
Decompression cable 2
NOTE:
Apply the lithium soap base grease on the
clutch cable end and decompression cable
end.
B
2
1
12. Adjust:
Clutch lever free play
Refer to “CLUTCH ADJUSTMENT”
section in the CHAPTER 3.
Decompression lever free play
Refer to “DECOMPRESSION LEVER
ADJUSTMENT” section in the CHAP-
TER 3.
13. Fasten the decompression cable 1 and
clutch cable 2 with a clamp 3.
1
2
3
14. Insert the end of the fuel breather hose
1 into the hole of the steering stem.
HANDLEBAR

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CHAS
EC560000
STEERING
Extent of removal:1 Lower bracket removal2 Bearing removal
Extent of removal Order Part name Q’ty Remarks
STEERING REMOVAL
WARNING
Support the machine securely so there is no
danger of it falling over.
Preparation for removal Hold the machine by placing the
suitable stand under the engine.
Headlight
Handlebar
Cable guide
Front fenderRefer to “HANDLEBAR” section.
1 Trip meter 1
2 Steering stem nut 1
3 Front fork 2 Refer to “FRONT FORK” section.
4 Upper bracket 1
5 Steering ring nut 1 Use special tool.
Refer to “REMOVAL POINTS”.
6 Lower bracket 1
7Ball race cover
1
2
1
STEERING

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CHASSTEERING
Extent of removal Order Part name Q’ty Remarks
8 Upper bearing 1
9 Lower bearing 1 Refer to “REMOVAL POINTS”.
10Ball race
2Refer to “REMOVAL POINTS”.
2

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CHAS
EC563000
REMOVAL POINTS
Steering ring nut
1. Remove:
Steering ring nut 1
Use the steering nut wrench 2.
WARNING
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.
CAUTION:
Take care not to damage the steering stem
thread.
EC563400
Ball race
1. Remove:
Ball race 1
Remove the ball race using long rod 2
and the hammer.
EC564000
INSPECTION
Steering stem
1. Inspect:
Steering stem 1
Bend/damage → Replace.
STEERING

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CHASSTEERING
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. If the bear-
ings hang up or are not smooth in their
operation in the ball races, replace
bearings and ball races as a set.
EC565000
ASSEMBLY AND INSTALLATION
Lower bracket
1. Install:
Lower bearing 1
NOTE:
Apply the lithium soap base grease on the dust
seal lip and bearing inner circumference.
2. Install:
Ball race
Upper bearing 1
Ball race cover 2
NOTE:
Apply the lithium soap base grease on the
bearing and ball race cover lip.
3. Install:
Lower bracket 1
NOTE:
Apply the lithium soap base grease on the
bearing and the portion a of the steering
stem.