Yamaha 2011 WR250FA Owner's Service Manual page 130

REAR SUSPENSION SETTING
The rear suspension setting should be made
depending on the rider's feeling of an actual run
and the circuit conditions.
The rear suspension setting includes the fol-
lowing two factors:
1. Setting of spring preload
• Change the set length of the spring.
• Change the spring.
2. Setting of damping force
• Change the rebound damping.
• Change the compression damping.
CHOOSING SET LENGTH
1. Place a stand or block under the engine to
put the rear wheel above the floor, and mea-
sure the length "a" between the rear wheel
axle center and the rear fender holding bolt.
2. Remove the stand or block from the engine
and with a rider astride the seat, measure
the sunken length "b" between the rear
wheel axle center and the rear fender hold-
ing bolt.
3. Loosen the locknut "1" and make adjust-
ment by turning the spring adjuster "2" to
achieve the standard figure from the sub-
traction of the length "b" from the length "a".
Standard figure:
90–100 mm (3.5–3.9 in)
• If the machine is new and after it is broken in,
the same set length of the spring may change
because of the initial fatigue, etc. of the
spring. Therefore, be sure to make reevalua-
tion.
• If the standard figure cannot be achieved by
adjusting the spring adjuster and changing
the spring set length, replace the spring with
an optional one and make readjustment.
SETTING OF SPRING AFTER
REPLACEMENT
After replacement, be sure to adjust the spring
to the set length [sunken length 90–100 mm
(3.5–3.9 in)] and set it.
1. Use of soft spring
• Set the soft spring for less rebound damping
to compensate for its less spring load. Run
with the rebound damping adjuster one or
two clicks on the softer side and readjust it to
suit your preference.
2. Use of stiff spring
• Set the soft spring for more rebound damp-
ing to compensate for its greater spring load.
Run with the rebound damping adjuster one
or two clicks on the stiffer side and readjust
it to suit your preference.
Adjusting the rebound damping will be followed
more or less by a change in the compression
damping. For correction, turn the low compres-
sion damping adjuster on the softer side.
When using a rear shock absorber other
than currently installed, use the one whose
overall length "a" does not exceed the stan-
dard as it may result in faulty performance.
Never use one whose overall length is
greater than standard.
4-4
CHASSIS