Front Suspension Adjustments; Front Suspension Air Pressure; Front Suspension Damping - Honda 2009 CRF450X Owner's Manual & Competition Handbook

Front Suspension Adjustments

The front suspension can be adjusted for the
rider's weight and riding conditions by using one
or more of the following methods:
• Oil volume — The effects of higher or lower
fork oil capacity are only felt during the final
100 mm (3.9 in) of fork travel.
• Compression damping — Turning the
compression damping adjuster adjusts how
quickly the fork compresses.
• Rebound damping — Turning the rebound
damping adjuster adjusts how quickly the fork
extends.
• Fork springs — Optional springs are
available in softer and stiffer types than the
standard rate. (page 168)
The inverted fork on your CRF features sealed
damper cartridges with dual (separate air and oil)
chambers to prevent aeration. The design also
isolates the oil in each fork tube/slider, which
may contain air bubbles and/or metal particles,
from the sealed cartridge to provide more
consistent damping.
(1)
(2)
(1) compression damping adjuster
(2) rebound damping adjuster
112
Adjustments for Competition
HONDA O/M CRF450X (Eu) 3RMEY620 00X3R-MEY-6200

Front Suspension Air Pressure

Air is an unstable gas which builds up pressure
as it is worked (such as in a fork). Air pressure
acts as a progressive spring and affects the entire
range of fork travel. This means the fork action
on your CRF will get stiffer during a race. For
this reason, release built-up air pressure in the
fork legs between motos. Be sure the fork is
fully extended with the front tyre off the ground
when you release the pressure.
The standard air pressure is 0 kPa (0 kgf/cm
psi). You may relieve accumulated air pressure in
the fork legs by using the fork air pressure
release screws. The front wheel should be off the
ground before you release the pressure. The air
pressure should be adjusted according to the
altitude and outside temperature.
1. Place an optional workstand under the engine,
so that the front wheel is off the ground.
Do not adjust air pressure with the front wheel
on the ground as this will give false pressure
readings.
2. Remove the fork air pressure release screw (1).
3. Check that the O-ring (2) is in good condition.
4. Install and tighten the fork air pressure release
screw to the specified torque:
1.2 N·m (0.1 kgf·m, 0.9 lbf·ft)
(1)
(2)
(1) fork air pressure release screw (2) O-ring

Front Suspension Damping

Rebound Damping Adjustment
The fork rebound damping adjuster (1) has 16
positions or more. Turning the adjuster screw one
full turn clockwise advances the adjuster four
positions. To adjust the rebound damping to the
standard setting, proceed as follows:
Turn the adjuster clockwise until it will no longer
turn (lightly seats). This is the full hard position.
The adjuster is set in the standard position when
the adjuster is turned counterclockwise 6 clicks.
2 , 0
Make sure that both fork legs are adjusted to the
same position.
Compression Damping Adjustment
This adjustment affects how quickly the fork
compresses. The fork compression damping
adjuster (2) has 16 positions or more. Turning the
adjuster screw one full turn changes the adjuster
four positions. To adjust the compression
damping adjuster to the standard position,
proceed as follows:
Turn the adjuster clockwise until it will no longer
turn (lightly seats). This is the full hard position.
The adjuster is set in the standard position when
the adjuster is turned counterclockwise 11 clicks.
Make sure that both fork legs are adjusted to the
same position.