steering YAMAHA YZ250F 2010 User Guide

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)

3-22
CHASSIS
h. Install the washer "5", upper bracket "6", steering stem nut "7",
handlebar "8", handlebar upper
holder "9" and number plate "10".
• Apply the lithium soap base grease on the contact surface of the steer-
ing stem nut when installing.
• The handlebar upper holder should
be installed with the punched mark
"a" forward.
• Install the handlebar so that the
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 breather hose "11" into the hole in the steer-
ing stem.
First tighten the bolts on the front
side of the handlebar upper holder,
and then tighten the bolts on the
rear side.
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 brack-
et): 21 Nm (2.1 m•kg, 15
ft•lb)
Number plate: 7 Nm (0.7 m•kg, 5.1
ft•lb)

5-28
STEERING
STEERING
REMOVING THE STEERINGOrder Part name Q'ty Remarks TIGHTENING STEPS:
• Tighten ring nut. 38 Nm (3.8 m•kg, 27 ft•lb)
• Loosen it one turn.
• Retighten it. 7 Nm (0.7 m•kg, 5.1 ft•lb)
Hold the machine by placing the suitable stand
under 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 2 Refer to "FRONT FORK" section.
4 Upper bracket 1
5 Steering ring nut 1 Refer to removal section.
6 Lower bracket 1
7 Bearing race cover 1
8 Upper bearing 1
9 Lower bearing 1 Refer to removal section.
10 Bearing race 2 Refer to removal section.

5-29
STEERING
HANDLING NOTE
Support the machine securely so
there is no danger of it falling over.
REMOVING THE STEERING RING
NUT
1. Remove:• Steering ring nut "1"Use the steering nut wrench "2".
Support the steering stem so that
it may not fall down.
REMOVING THE LOWER
BEARING
1. Remove:
• Lower bearing "1"Use the floor chisel "2".
Take care not to damage the steer-
ing shaft thread.
REMOVING THE BEARING RACE
1. Remove:
• Bearing race "1"Remove the bearing race using
long rod "2" and the hammer. CHECKING THE STEERING STEM
1. Inspect:
• Steering stem "1"Bend/damage →Replace.
CHECKING THE BEARING AND
BEARING RACE
1. Wash the bearings and bearing races with a solvent.
2. Inspect: •Bearing "1"
• Bearing race
Pitting/damage →Replace bear-
ings and bearing races 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 set.
INSTALLING THE LOWER
BRACKET
1. Install: • Lower bearing "1"
Apply the lithium soap base grease
on the dust seal lip and bearing inner
circumference.
2. Install:
• Bearing race
• Upper bearing "1"
• Bearing race cover "2"
Apply the lithium soap base grease
on the bearing and bearing race cov-
er lip.
3. Install:• Lower bracket "1"
Apply the lithium soap base grease
on the bearing, the portion "a" and
thread of the steering stem.
4. Install:• Steering ring nut "1"
Install the steering nut with its
stepped side "a" facing downward.
Tighten the steering ring nut using
the steering nut wrench "2".
Refer to "CHECKING AND AD-
JUSTING THE STEERING
HEAD" section in the CHAPTER
3.
Steering nut wrench:
YU-33975/90890-01403
Steering ring nut:
7 Nm (0.7 m•kg, 5.1 ft•
lb)

5-30
STEERING
5. 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.
6. Install: • Washer "1"
7. Install: • Front fork "1"
• Upper bracket "2"
• Temporarily tighten the pinch bolts (lower bracket).
• Do not tighten the pinch bolts (up- per bracket) yet.
8. Install:
• Steering stem nut "1"
Apply the lithium soap base grease
on the contact 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.
10. Adjust: • Front fork top end "a"
11. Tighten: • Pinch bolt (upper bracket) "1"
• Pinch bolt (lower bracket) "2"
Tighten the lower bracket to speci-
fied torque. If to rqued too much, it
may cause the front fork to mal-
function.
Steering stem nut: 145 Nm (14.5 m•kg, 105
ft•lb)
Front fork top end (stan-
dard) "a":5 mm (0.20 in)
Pinch bolt (upper brack-
et): 21 Nm (2.1 m•kg, 15
ft•lb)
Pinch bolt (lower brack-
et): 21 Nm (2.1 m•kg, 15
ft•lb)