2006 YAMAHA YZ450F torque

5 - 41
CHAS
33. Install:
Protector guide 1
NOTE:
Install the protector guide with its wider side a
facing downward.
Installation
1. Install:
Front fork 1
NOTE:
Temporarily tighten the pinch bolts (under
bracket).
Do not tighten the pinch bolts (handle crown)
yet.
2. Tighten:
Damper assembly 1
NOTE:
Use the cap bolt ring wrench 2 to tighten the
damper assembly with specified torque.
Cap bolt ring wrench:
YM-01501/90890-01501
T R..30 Nm (3.0 m · kg, 22 ft · lb)
3. Adjust:
Front fork top end a
Front fork top end (standard) a:
Zero mm (Zero in)
FRONT FORK

5 - 42
CHAS
4. Tighten:
Pinch bolt (handle crown) 1
Pinch bolt (under bracket) 2
CAUTION:
Tighten the under bracket to specified
torque. If torqued too much, it may cause
the front fork to malfunction.
T R..23 Nm (2.3 m · kg, 17 ft · lb)
T R..20 Nm (2.0 m · kg, 14 ft · lb)
5. Install:
Protector 1
Bolt (protector) 2
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
6. Adjust:
Rebound damping force
NOTE:
Turn in the damping adjuster 1 finger-tight
and then turn out to the originally set position.
7. Adjust:
Compression damping force
NOTE:
Turn in the damping adjuster 1 finger-tight
and then turn out to the originally set position.
FRONT FORK

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CHASSTEERING
9. After tightening the nut, check the steering
for smooth movement. If not, adjust the
steering by loosening the ring nut little by
little.
10. Adjust:
•Front fork top end a
Front fork top end (standard)
a:
Zero mm (Zero in)
11. Tighten:
•Pinch bolt (handle crown) 1
•Pinch bolt (under bracket) 2
CAUTION:
Tighten the under bracket to specified
torque. If torqued too much, it may cause
the front fork to malfunction.
T R..23 Nm (2.3 m · kg, 17 ft · lb)
T R..20 Nm (2.0 m · kg, 14 ft · lb)

7 - 20
TUNSETTING
EC72H002
Suspension setting
•Front fork
NOTE:
•If any of the following symptoms is experienced with the standard position as the base, make
resetting by reference to the adjustment procedure given in the same chart.
•Before any change, set the rear shock absorber sunken length to the standard figure 90 ~ 100 mm
(3.5 ~ 3.9 in).
SymptomSection
Check Adjust
JumpLarge
gapMedium
gapSmall
gap
Stiff over entire rangeCompression damping Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Oil amount Decrease oil amount by about 5 ~ 10 cm
3 (0.2 ~
0.4 Imp oz, 0.2 ~ 0.3 US oz).
Spring Replace with soft spring.
Unsmooth movement
over entire rangeOuter tube Check for any bends, dents, and other noticeable
scars, etc. If any, replace affected parts.
Inner tube
Slide metal Replace with a new one for extended use.
Piston metal Replace with a new one for extended use.
Under bracket tightening
torqueRetighten to specified torque.
Poor initial
movementRebound damping Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Oil seal Apply grease in oil seal wall.
Soft over entire
range, bottoming outCompression damping Turn adjuster clockwise (about 2 clicks) to increase
damping.
Oil amount Increase oil amount by about 5 ~ 10 cm
3 (0.2 ~
0.4 Imp oz, 0.2 ~ 0.3 US oz).
Spring Replace with stiff spring.
Stiff toward stroke
endOil amountDecrease oil amount by about 5 cm
3 (0.2 Imp oz,
0.2 US oz).
Soft toward stroke
end, bottoming outOil amountIncrease oil amount by about 5 cm
3 (0.2 Imp oz,
0.2 US oz).
Stiff initial movement Compression dampingTurn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Low front, tending to
lower front postureCompression damping Turn adjuster clockwise (about 2 clicks) to increase
damping.
Rebound damping Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Balance with rear end Set sunken length for 95 ~ 100 mm (3.7 ~ 3.9 in) when
one passenger is astride seat (lower rear posture).
Oil amount Increase oil amount by about 5 cm
3 (0.2 Imp oz,
0.2 US oz).
“Obtrusive” front,
tending to upper front
postureCompression damping Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Balance with rear end Set sunken length for 90 ~ 95 mm (3.5 ~ 3.7 in)
when one passenger is astride seat (upper rear pos-
ture).
Spring Replace with soft spring.
Oil amount Decrease oil amount by about 5 ~ 10 cm
3 (0.2 ~
0.4 Imp oz, 0.2 ~ 0.3 US oz).