Tire Pressure; Front Fork Setting; Change In Amount And Characteristics Of Fork Oil - Yamaha YZ250F Owner's Service Manual

TIRE PRESSURE

EAS1SM5370
Tire pressure should be adjusted to suit the
road surface condition of the circuit.
Standard tire pressure
100 kPa (1.0 kgf/cm
• Under a rainy, a muddy, a sandy, or a slippery
condition, the tire pressure should be lower
for a larger area of contact with the road sur-
face.
Extent of adjustment
60–80 kPa (0.6–0.8 kgf/cm
12 psi)
• Under a stony or a hard road condition, the
tire pressure should be higher to prevent a flat
tire.
Extent of adjustment
100–120 kPa (1.0–1.2 kgf/cm
15–18 psi)

FRONT FORK SETTING

EAS1SM5371
The front fork setting should be made depend-
ing on the rider's feeling of an actual run and
the circuit conditions.
The front fork setting includes the following
three factors:
1. Setting of air spring characteristics
• Change the fork oil amount.
2. Setting of spring preload
• Change the spring.
3. Setting of damping force
• Change the compression damping force.
• Change the rebound damping force.
The spring acts on the load and the damping
force acts on the cushion travel speed.
CHANGE IN AMOUNT AND CHARACTERIS-
EAS1SM5372
TICS OF FORK OIL
Damping characteristic near the final stroke
can be changed by changing the fork oil
amount.
EWA1DX4001
Adjust the oil amount in 5 cm
0.2 Imp.oz) increments or decrements. Too
small oil amount causes the front fork to
2
produce a noise at full rebound or the rider
,15 psi)
to feel some pressure on his hands or body.
Alternatively, too large oil amount will
cause the air spring characteristics to have
a tendency to be stiffer with the consequent
deteriorated performance and characteris-
tics. Therefore, adjust the front fork within
the specified range.
2
, 9.0–
2
,
10-2
WARNING
Standard oil amount
3
335 cm (11.33 US oz, 11.82
lmp.oz) (USA) (CAN)
3
355 cm (12.00 US oz, 12.52
lmp.oz) (EUR) (JPN) (AUS) (NZL)
(ZAF)
Extent of adjustment
300–365 cm
oz, 10.58–12.87 Imp.oz)
A. Air spring characteristics in relation to oil
amount change
B. Load
C. Stroke
1. Max. oil amount
2. Standard oil amount
3. Min. oil amount
CHASSIS
3
(0.2 US oz,
3
(10.14–12.34 US