Yamaha YZ250F X 2008 Owner'S Service Manual Download

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7-7

CHASSIS

C. Stroke
1.

Max. oil amount

Standard oil amount

Min. oil amount

SETTING OF SPRING AFTER
REPLACEMENT
As the front fork setting can be easily
affected by rear suspension, take
care so that the machine front and
rear are balanced (in position, etc.)
when setting the front fork.
1. Use of soft spring

• Change the rebound damping.

Turn out one or two clicks.

• Change the compression damp-

ing.
Turn in one or two clicks.

Generally a soft spring gives a soft
riding feeling. Rebound damping
tends to become stronger and the
front fork may sink deeply over a se-
ries of gaps.

2. Use of stiff spring

• Change the rebound damping.

Turn in one or two clicks.

• Change the compression damp-

ing.
Turn out one or two clicks.

Generally a stiff spring gives a stiff
riding feeling. Rebound damping
tends to become weaker, resulting in
lack of a sense of contact with the
road surface or in a vibrating handle-
bar.

FRONT FORK SETTING PARTS
• Front fork spring "1"

The I.D. mark (slits) "a" is proved on

the end of the spring.

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 following 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 damp-

ing.

CHOOSING SET LENGTH
1. Place a stand or block under the

engine to put the rear wheel
above the floor, and measure 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
holding bolt.

3. Loosen the locknut "1" and make

adjustment by turning the spring
adjuster "2" to achieve the stan-
dard figure from the subtraction of
the length "b" from the length "a".

• 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 reeval-
uation.

• 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 readjust-
ment.

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 re-

bound 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 re-

bound damping to compensate
for its greater spring load. Run
with the rebound damping adjust-
er 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 cor-
rection, turn the low compression
damping adjuster on the softer side.

TY
PE

SPRIN

RATE

SPRING

PART NUM-

BER

I.D.
MA

(slit

0.398

1C3-23141-A1

0.408

1C3-23141-B1