YAMAHA YFM250R 2011 Service Manual

4-16
4 3. Tighten the locknut to the specified torque.
NOTICE: Always tighten the locknut
against the adjusting nut, and then tighten
it to the specified torque.
[ECB00081]
Rebound damping force
Turn the rebound damping force adjusting screw in
direction (a) to increase the rebound damping
force and thereby harden the damping, and in di-
rection (b) to decrease the rebound damping force
and thereby soften the damping.Tightening torque:
Locknut:
42 Nm (4.2 m·kgf, 30 ft·lbf)
1. Rebound damping force adjusting screwRebound damping setting:
Minimum (soft):
20 click(s) in direction (b)*
Standard:
12 click(s) in direction (b)*
Maximum (hard):
3 click(s) in direction (b)*
* With the adjusting screw fully turned in di-
rection (a)
(a) (b) 1
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4-17
4Compression damping force
Compression damping force (for fast compression
damping)To increase the compression damping force and
thereby harden the compression damping, turn the
compression damping force adjusting bolt in direc-
tion (a). To decrease the compression damping
force and thereby soften the compression damp-
ing, turn the adjusting bolt in direction (b).
Compression damping force (for slow compres-
sion damping)To increase the compression damping force and
thereby harden the compression damping, turn the
compression damping force adjusting screw in di-
rection (a). To decrease the compression damping
force and thereby soften the compression damp-
ing, turn the adjusting screw in direction (b).
1. Compression damping force adjusting bolt (for fast
compression damping)
(b)(a)
1
Compression damping setting (for fast com-
pression damping):
Minimum (soft):
4 turn(s) out from the fully turned in posi-
tion
Standard:
2 turn(s) out from the fully turned in posi-
tion
Maximum (hard):
Adjusting bolt fully turned in
U1BT61E0.book Page 17 Tuesday, April 6, 2010 1:28 PM

4-18
4
WARNING
EWB00410These shock absorber assemblies contain
highly pressurized nitrogen gas. Read and un-
derstand the following information before han-
dling the shock absorber assemblies.
Do not tamper with or attempt to open the
cylinder assemblies.
Do not subject the shock absorber assem-
blies to an open flame or other high heat
source. This may cause the unit to explode
due to excessive gas pressure.
Do not deform or damage the cylinders in
any way. Cylinder damage will result in poor
damping performance.
Do not dispose of a damaged or worn out
shock absorber assembly yourself. Take the
shock absorber assembly to a Yamaha deal-
er for any service.EBU28243Adjusting the rear shock absorber as-
sembly (YFM25RA/YFM250RA)The spring preload can be adjusted to suit the rid-
er’s weight and the riding conditions.
1. Compression damping force adjusting screw (for slow
compression damping)Compression damping setting (for slow com-
pression damping):
Minimum (soft):
16 click(s) in direction (b)*
Standard:
10 click(s) in direction (b)*
Maximum (hard):
1 click(s) in direction (b)*
* With the adjusting screw fully turned in di-
rection (a)
(b)(a)
1
U1BT61E0.book Page 18 Tuesday, April 6, 2010 1:28 PM

4-19
4
NOTICEECB01090Never turn the adjusting mechanism beyond
the minimum and maximum settings.Adjust the spring preload as follows.
1. Loosen the locknut.
2. Turn the spring preload adjusting nut in direc-
tion (a) to increase the spring preload and
thereby harden the suspension, and in direc-
tion (b) to decrease the spring preload and
thereby soften the suspension.
TIP
A special wrench can be obtained at a Yamaha
dealer to make this adjustment.
The spring preload setting is determined by
measuring distance A, shown in the illustration.
The shorter distance A is, the higher the spring
preload; the longer distance A is, the lower the
spring preload. With each complete turn of the
adjusting nut, distance A is changed by 1.0 mm
(0.04 in).3. Tighten the locknut to the specified torque.
NOTICE: Always tighten the locknut
against the adjusting nut, and then tighten
it to the specified torque.
[ECB00081]
1. Locknut
2. Spring preload adjusting nut
3. Distance A
2
1
(b) 3(a)
Spring preload setting:
Minimum (soft):
Distance A = 234.0 mm (9.21 in)
Standard:
Distance A = 230.0 mm (9.06 in)
Maximum (hard):
Distance A = 222.0 mm (8.74 in)
U1BT61E0.book Page 19 Tuesday, April 6, 2010 1:28 PM

4-20
4
WARNING
EWB00450This shock absorber assembly contains highly
pressurized nitrogen gas. If the shock absorb-
er assembly is damaged, it could explode
causing injury or property damage. Shock ab-
sorber cylinder damage could also result in
poor handling which could cause an accident.
Do not tamper with or attempt to open the
cylinder assembly.
Do not subject the shock absorber assembly
to an open flame or other high heat.
Do not deform or damage the cylinder in any
way.
Do not dispose of a damaged or worn out
shock absorber assembly yourself. Take the
shock absorber assembly to a Yamaha deal-
er for any service.
EBU29312Adjusting the rear shock absorber as-
sembly (YFM25RSEA/YFM250RSEA)The spring preload, rebound damping and com-
pression damping forces of the rear shock absorb-
er assembly can be adjusted to suit the rider’s
weight and the riding conditions.
WARNING
EWB02500Suspension components become hot during
operation. Never touch the compression
damping force adjusting screw, the rebound
damping force adjusting dial or the oil reser-
voir with your bare hand or skin until suspen-
sion components have cooled.NOTICEECB00090Never turn an adjusting mechanism beyond
the minimum and maximum settings.Spring preload
1. Loosen the locknut. Tightening torque:
Locknut:
42 Nm (4.2 m·kgf, 30 ft·lbf)
U1BT61E0.book Page 20 Tuesday, April 6, 2010 1:28 PM

4-21
42. Turn the spring preload adjusting nut in direc-
tion (a) to increase the spring preload and
thereby harden the suspension, and in direc-
tion (b) to decrease the spring preload and
thereby soften the suspension.
TIP
A special wrench can be obtained at a Yamaha
dealer to make this adjustment.
The spring preload setting is determined by
measuring distance A, shown in the illustration.
The shorter distance A is, the higher the spring
preload; the longer distance A is, the lower thespring preload. With each complete turn of the
adjusting nut, distance A is changed by 1.5 mm
(0.06 in).1. Locknut
2. Spring preload adjusting nut
12
(a)
(b)
Spring preload setting:
Minimum (soft):
Distance A = 232.0 mm (9.13 in)
Standard:
Distance A = 228.0 mm (8.98 in)
Maximum (hard):
Distance A = 220.0 mm (8.66 in)1. Distance A
1
U1BT61E0.book Page 21 Tuesday, April 6, 2010 1:28 PM

4-22
4 3. Tighten the locknut to the specified torque.
NOTICE: Always tighten the locknut
against the adjusting nut, and then tighten
it to the specified torque.
[ECB00081]
Rebound damping force
Turn the rebound damping force adjusting dial in
direction (a) to increase the rebound damping
force and thereby harden the damping, and in di-
rection (b) to decrease the rebound damping force
and thereby soften the damping.Tightening torque:
Locknut:
42 Nm (4.2 m·kgf, 30 ft·lbf)
1. Rebound damping force adjusting dialRebound damping setting:
Minimum (soft):
20 click(s) in direction (b)*
Standard:
12 click(s) in direction (b)*
Maximum (hard):
3 click(s) in direction (b)*
* With the adjusting dial fully turned in direc-
tion (a)
1
(a)
(b)
U1BT61E0.book Page 22 Tuesday, April 6, 2010 1:28 PM

4-23
4Compression damping force
Turn the compression damping force adjusting
screw in direction (a) to increase the compression
damping force and thereby harden the damping,
and in direction (b) to decrease the compression
damping force and thereby soften the damping.
TIPAlthough the total number of clicks of a damping
force adjusting mechanism may not exactly match
the above specifications due to small differences in
production, the actual number of clicks always rep-
resents the entire adjusting range. To obtain a pre-
cise adjustment, it would be advisable to check the
number of clicks of each damping force adjusting
mechanism and to modify the specifications as
necessary.
1. Compression damping force adjusting screw
1 (a)
(b)
Compression damping setting:
Minimum (soft):
12 click(s) in direction (b)*
Standard:
7 click(s) in direction (b)*
Maximum (hard):
2 click(s) in direction (b)*
* With the adjusting screw fully turned in di-
rection (a)
U1BT61E0.book Page 23 Tuesday, April 6, 2010 1:28 PM

4-24
4
WARNING
EWB00430This shock absorber assembly contains highly
pressurized nitrogen gas. Read and under-
stand the following information before han-
dling the shock absorber assembly.
Do not tamper with or attempt to open the
cylinder assembly.
Do not subject the shock absorber assembly
to an open flame or other high heat source.
This may cause the unit to explode due to ex-
cessive gas pressure.
Do not deform or damage the cylinder in any
way. Cylinder damage will result in poor
damping performance.
Do not dispose of a damaged or worn out
shock absorber assembly yourself. Take the
shock absorber assembly to a Yamaha deal-
er for any service.
U1BT61E0.book Page 24 Tuesday, April 6, 2010 1:28 PM

5-1
5
EBU19201
PRE-OPERATION CHECKS
EBU19224Inspect your vehicle each time you use it to make sure the vehicle is in safe operating condition. Always
follow the inspection and maintenance procedures and schedules described in the Owner’s Manual.
WARNING
EWB00481Failure to inspect or maintain the vehicle properly increases the possibility of an accident or equip-
ment damage. Do not operate the vehicle if you find any problem. If a problem cannot be corrected
by the procedures provided in this manual, have the vehicle inspected by a Yamaha dealer.Before using this vehicle, check the following points:
ITEM ROUTINE PAGE
FuelCheck fuel level in fuel tank, and add recommended fuel if neces-
sary.
Check fuel line for leakage. Correct if necessary.4-8, 5-3
Engine oilCheck oil level in engine, and add recommended oil to specified lev-
el if necessary.
Check ATV for oil leakage. Correct if necessary.5-3, 8-11
Front brakeCheck operation. If soft or spongy, have Yamaha dealer bleed hy-
draulic system.
Check brake pads for wear, and replace if necessary.
Check brake fluid level in reservoir, and add recommended brake
fluid to specified level if necessary.
Check hydraulic system for leakage. Correct if necessary.5-3, 8-22, 8-23, 8-25
U1BT61E0.book Page 1 Tuesday, April 6, 2010 1:28 PM