Chassis Adjustments; Rear End; Fork Height/Angle; Wheelbase - Honda CRF150R 2020 Owner's Manual & Competition Handbook

The following suggestions may improve a specific
concern. Subtle changes in overall handling may
also be noted.

Rear End

If you have a problem with rear wheel traction,
raise the rear end of your CRF by increasing the
rear spring pre-load. Instead of running 3.3 in (85
mm) of sag, you can run 3.1 in (80 mm) or 3.0 in
(75 mm) so the rear of the bike will sit a little
higher. This should produce more traction because
of the change to the swingarm and location of your
CRF's center of gravity.
If you have a problem with the steering head
shaking when you use the front brake hard or if
your CRF wants to turn too quickly, lower the rear
of the motorcycle by reducing the rear spring pre-
load. This will increase fork rake and trail and
should improve stability in a straight line. The
effective suspension travel will be transferred
toward the firmer end of wheel travel.
Keep the race sag adjustment (page 104) in the
3.3 – 4.1 in (85 – 105 mm) range.

Fork Height/Angle

The position of the fork tubes in the clamps is not
adjustable. Align the groove in the outer tube with
the top surface of the upper fork clamp.
Standard Position
Align the groove (1) in the outer tube with the top
surface of the upper fork clamp (2).
(1)
(1) groove (2) upper fork clamp

Wheelbase

Adjusting your CRF's wheelbase can offer subtle
changes in overall handling. You may adjust
wheelbase by adding or removing links on the
drive chain. If you change the wheelbase, be sure
to recheck race sag and adjust it, if necessary.
In the past, a general rule was lengthen the
wheelbase to add straight line stability, shorten the
wheelbase to improve turning. However, we
suggest you do not lengthen the wheelbase of your
CRF unless you are racing on a track with more
fast sections than normal.
As a general recommendation, keep the wheelbase
as short as possible. This positions the wheels
closer together, improves turning response,
increases weighting (traction) on the rear wheel,
(2)
and reduces weight on the front wheel.
With your CRF, you will probably find that the
standard setting or a shorter wheelbase will offer
more overall benefits.

Chassis Adjustments

123
Adjustments for Competition