Honda CR250R Owner'S Manual & Competition Handbook Download

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Rear Suspension Adjustments

Rear Suspension Race Sag

Setting the proper race sag (ride height) is very
important for competition use.

Race sag refers to the amount of rear wheel travel
used by your CR at rest, ready to ride, with you
on the seat. As a general rule of thumb, the race
sag dimension should be about one-third of the
maximum travel.

On your CR, ride height is changed by adjusting
the rear suspension spring pre-load.

Spring Pre-load & Race Sag Adjustment
The following adjustment procedure establishes
the correct starting point for any suspension
tuning — the proper rear spring pre-load
adjustment for your specific needs.
Your CR should be at normal racing weight,
including fuel and transmission oil. You should
be wearing all your normal protective apparel.
You will need two helpers.

To calculate the proper adjustment, it is necessary
to measure between two fixed points — from the
top of the most rearward point of the subframe
down to the machined edge at the rear of the
swingarm, as illustrated — for three different
situations:

unloaded

: motorcycle on optional workstand with

rear suspension fully extended, no rider.

loaded with rider

: motorcycle on ground, with

rider.

loaded without rider

: motorcycle on ground,

without rider
1. Support your CR on a workstand with the rear

wheel off the ground.

2. Measure the

unloaded

dimension.

3. Measure the

loaded with rider

dimension.

Remove the workstand. With two helpers
available, sit as far forward as possible on
your CR’s seat, wearing your riding apparel.
Ask one helper to steady your CR perfectly
upright so you can put both feet on the pegs.
Bounce your weight on the seat a couple of
times to help the suspension overcome any
stiction and settle to a good reference point.

Ask the other helper to measure the

loaded

with rider

dimension.

Race Sag Calculation:
unloaded

23.6 in (600 mm)

—loaded with rider

19.7 in (500 mm)

Race Sag

3.9 in (100 mm)

4. Calculate the

race sag

dimension.

To do this, subtract the

loaded with rider

dimension (step 3) from the

unloaded

dimension (step 2).

Standard Race Sag:

3.9 in (100 mm)

Adjust spring pre-load as necessary to obtain the
desired handling results.
Decreasing the race sag dimension (example: 3.5
in, 90 mm) improves turning ability for tight
terrain at the cost of slightly reduced straight line
stability.
Increasing the race sag dimension (example: 4.3
in, 110 mm) may improve stability on faster
terrain with less turns, but will reduce turning
performance slightly and may upset the balance
between the front and rear suspension, producing
a harsher ride. This will happen if the adjustment
shifts the effective wheel travel toward the more
progressive end of its range.

5. Measure the

loaded without rider

dimension.

Do this with your CR set at the standard race
sag.

Free Sag Calculation:
unloaded

23.6 in (600 mm)

—loaded without rider 21.6 in (550 mm)
Free Sag

2.0 in (50 mm)

Adjustments for Competition

UNLOADED MEASUREMENT
(on workstand, without rider)

EXAMPLE: 23.6 in (600 mm)

LOADED MEASUREMENT
(on ground, with rider)