Yamaha YZ250F 2016 Service Manual

CHASSIS
3-31
EAS1SM9102
CHECKING THE SWINGARM OPERATION
1. Check:
• Swingarm smooth action
• Swingarm free play
Refer to “SWINGARM” on page 4-60.
EAS1SM9103
CHECKING THE REAR SUSPENSION
1. Stand the vehicle upright on a level surface.
EWA
WARNING
Securely support the vehicle so that there is
no danger of it falling over.
2. Check:
• Rear shock absorber assembly
Gas leaks/oil leaks  Replace the rear
shock absorber assembly.
Refer to “REAR SHOCK ABSORBER AS-
SEMBLY” on page 4-53.
3. Check:
• Rear shock absorber assembly smooth ac-
tion
• Rear suspension link smooth action
Sit astride the seat and shake your body up
and down several times to check whether
the rear shock absorber assembly operates
smoothly.
Unsmooth operation  Correct or replace.
Refer to “REAR SHOCK ABSORBER AS-
SEMBLY” on page 4-53.
EAS1SM9104
ADJUSTING THE REAR SHOCK ABSORB-
ER ASSEMBLY
Use a suitable stand to raise the rear wheel off
the ground.
EWA13120
WARNING
Securely support the vehicle so that there is
no danger of it falling over.
Spring preload
ECA@
NOTICE
Do not turn the adjuster forcibly beyond its
adjusting range.
1. Remove:
• Rear frame
Refer to “REAR SHOCK ABSORBER AS-
SEMBLY” on page 4-53.
2. Adjust:
• Spring preload
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Loosen the locknut “1”.
b. Loosen the adjuster “2” until there is some
clearance between the spring and the ad-
juster.
c. Measure the spring free length “a”.
d. Turn the adjuster in the direction of “b” or “c”
to make an adjustment.
TIP
• Be sure to remove all dirt and mud from
around the locknut and adjusting ring before
adjustment.
• The length of the spring (installed) changes
1.5 mm (0.06 in) per turn of the adjusting ring.
Direction “b”
Spring preload is increased (suspen-
sion is harder).
Direction “c”
Spring preload is decreased (suspen-
sion is softer).
Spring preload adjusting positions
Minimum
Position in which the spring is
turned in 1.5 mm (0.06 in) from
its free length.
Standard
Position in which the spring is
turned in 10 mm (0.39 in) from its
free length.
Maximum
Position in which the spring is
turned in 18 mm (0.71 in) from its
free length.

Yamaha YZ250F 2016 Specifications

General

Displacement	250cc
Bore x Stroke	77.0mm x 53.6mm
Compression Ratio	13.5:1
Ignition	TCI
Transmission	5-speed
Final Drive	Chain
Suspension Rear	KYB® single shock; fully adjustable, 12.4-in travel
Brakes Front	Hydraulic single disc brake, 250mm
Brakes Rear	Hydraulic single disc brake, 245mm
Tires Front	80/100-21
Tires Rear	100/90-19
Length	85.6 in
Width	32.5 in
Seat Height	38.0 in
Rake (Caster Angle)	27.3°
Ground Clearance	12.8 in
Fuel Capacity	2.0 gal
Engine Type	Liquid-cooled, DOHC, 4-stroke, 4-valve
Fuel Delivery	Yamaha Fuel Injection (YFI), Keihin® 44mm
Suspension Front	KYB® Speed-Sensitive System, inverted fork; fully adjustable, 12.2-in travel