Page 41 of 142
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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4-19
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.
TIPA 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)
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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
Page 47 of 142
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
Page 88 of 142
8-2
8
EBU29790Owner’s manual and tool kit Be sure to put this owner’s manual in the cover and
always carry it along with the low-pressure tire
gauge and the owner’s tool kit under the seat.
The service information included in this manual
and the tools provided in the owner’s tool kit are in-
tended to assist you in the performance of preven-
tive maintenance and minor repairs. However,
additional tools such as a torque wrench may be
necessary to perform certain maintenance work
correctly.
TIPIf you do not have the tools or experience required
for a particular job, have a Yamaha dealer perform
it for you.
1. Low-pressure tire gauge
2. Owner’s tool kit
3. Owner’s manual
4. Manual cover123
4
43
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Page 96 of 142
8-10
82. Check the spark plug for electrode erosion
and excessive carbon or other deposits, and
replace it if necessary.
3. Measure the spark plug gap with a wire thick-
ness gauge and, if necessary, adjust the gap
to specification.To install the spark plug
1. Clean the surface of the spark plug gasket
and its mating surface, and then wipe off any
grime from the spark plug threads.
2. Install the spark plug with the spark plug
wrench, and then tighten it to the specified
torque.
TIPIf a torque wrench is not available when installing
the spark plug, a good estimate of the correct
torque is 1/4–1/2 turn past finger tight. However,
the spark plug should be tightened to the specified
torque as soon as possible.3. Install the spark plug cap. Specified spark plug:
NGK/DR7EA
1. Spark plug gapSpark plug gap:
0.6–0.7 mm (0.024–0.028 in)
Tightening torque:
Spark plug:
18 Nm (1.8 m·kgf, 13 ft·lbf)
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8-13
8 6. Install a new oil filter element and new O-
rings.
TIPMake sure that the O-rings are properly seated.7. Install the oil filter element cover by installing
the bolts, and then tighten them to the speci-
fied torque.8. Install the engine oil drain bolt and its new
gasket, and then tighten the bolt to the speci-
fied torque.
9. Refill with the specified amount of the recom-
mended engine oil, and then install and tight-
en the engine oil filler cap.
TIPBe sure to wipe off spilled oil on any parts after the
engine and exhaust system have cooled down.
1. Oil filter element
2. O-ringTightening torque:
Oil filter element cover bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
1
2
2
Tightening torque:
Engine oil drain bolt:
20 Nm (2.0 m·kgf, 14 ft·lbf)
Recommended oil:
See page 10-1.
Oil quantity:
Without oil filter element replacement:
1.25 L (1.32 US qt, 1.10 Imp.qt)
With oil filter element replacement:
1.35 L (1.43 US qt, 1.19 Imp.qt)
U1BT61E0.book Page 13 Tuesday, April 6, 2010 1:28 PM
Page 105 of 142
8-19
8 4. Check the gasket for damage, and replace it if
necessary.
5. Make sure the gasket is properly positioned,
then insert the tailpipe into the muffler and
align the bolt holes.6. Install the bolts and tighten them to the speci-
fied torque.
WARNING
EWB02340Do not start the engine when cleaning the
spark arrester, otherwise it could cause injury
to the eyes, burns, carbon monoxide poison-
1. Tailpipe
2. Spark arrester
2 1
1. Gasket
2. Tailpipe
3. BoltTightening torque:
Tailpipe bolt:
11 Nm (1.1 m·kgf, 8.0 ft·lbf)
1 2
33
U1BT61E0.book Page 19 Tuesday, April 6, 2010 1:28 PM