2010 YAMAHA YFM250R torque

4-14
4
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]
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.
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)
Tightening torque:
Locknut:
42 Nm (4.2 m·kgf, 30 ft·lbf)
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8-2
8 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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8-9
82. Check the spark plug for electrode erosion
and excessive carbon or other deposits, and
replace it if necessary.
To install the spark plug
1. Measure the spark plug gap with a wire thick-
ness gauge and, if necessary, adjust the gap
to specification.
2. Clean the surface of the spark plug gasket
and its mating surface, and then wipe off any
grime from the spark plug threads.
3. Install the spark plug with the spark plug
wrench, and then tighten it to the specified
torque. Specified spark plug:
NGK/DR7EA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
1. Spark plug gapTightening torque:
Spark plug:
17.5 Nm (1.75 m·kgf, 12.7 ft·lbf)
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8-10
8
TIPIf a torque wrench is not available when installing
a 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.4. Install the spark plug cap.EBU28954Engine oil and oil filter element The engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter element must be replaced at the inter-
vals specified in the periodic maintenance and lu-
brication chart.
To check the engine oil level
1. Place the ATV on a level surface.
2. Check the engine oil level on a cold engine.TIPIf the engine was started before checking the oil
level, be sure to warm up the engine sufficiently,
and then wait at least ten minutes until the oil set-
tles for an accurate reading.
3. Remove the engine oil filler cap, and then
wipe the engine oil dipstick off with a clean
rag.
4. Insert the dipstick into the filler hole (without
screwing it in), and then remove it again to
check the oil level.TIPThe engine oil should be between the minimum
and maximum level marks.1. Engine oil filler cap
2. Engine oil dipstick
3. Maximum level mark
4. Minimum level mark
1
2
3
4 1
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8-12
8 6. Check the O-rings for damage and replace
them if necessary.7. Install a new oil filter element.
TIPMake sure that the O-rings are properly seated.8. Install the oil filter element cover by installing
the bolts, and then tighten them to the speci-
fied torque.
1. Oil filter element cover
2. Bolt
1 2
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
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8-13
89. Install the engine oil drain bolt and tighten it to
the specified torque.
10. 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.
NOTICEECB00300
In order to prevent clutch slippage (since the
engine oil also lubricates the clutch), do not
mix any chemical additives. Do not use oils
with a diesel specification of “CD” or oils of
a higher quality than specified. In addition,
do not use oils labeled “ENERGY CONSERV-
ING II” or higher.
Make sure that no foreign material enters the
crankcase.11. Start the engine, and then let it idle for several
minutes while checking it for oil leakage. If oil
is leaking, immediately turn the engine off and
check for the cause.
12. Turn the engine off, wait at least ten minutes,
and then check the oil level and correct it if
necessary.EBU23706Cleaning the air filter element The air filter element should be cleaned at the in-
tervals specified in the periodic maintenance and
lubrication chart. Clean or, if necessary, replace
the air filter element more frequently if you are
riding in unusually wet or dusty areas. 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)
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8-19
85. 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-ing, possibly leading to death, and start a fire.
Always let the exhaust system cool prior to
touching exhaust components.
EBU23940Adjusting the carburetor The carburetor should be checked and, if neces-
sary, adjusted at the intervals specified in the peri-
odic maintenance and lubrication chart. The
carburetor is an important part of the engine and
requires very sophisticated adjustment. Therefore,
most carburetor adjustments should be left to a
Yamaha dealer, who has the necessary profes-
sional knowledge and experience. The adjustment
described in the following section, however, may
be performed by the owner as part of routine main-
tenance.NOTICEECB00480The carburetor has been set and extensively
tested at the Yamaha factory. Changing these
settings without sufficient technical knowl-
edge may result in poor performance of or
damage to the engine.
1. Gasket
2. Tailpipe
3. BoltTightening torque:
Tailpipe bolt:
11 Nm (1.1 m·kgf, 8.0 ft·lbf)
1 2
33
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8-27
8
TIPIf the cable length cannot be adjusted to specifica-
tion, consult a Yamaha dealer.5. Tighten the locknut on the brake cable.
6. Turn in the adjusting bolt at the rear brake cal-
iper until it feels tight, then turn it out 1/8 turn
and tighten its locknut to the specified torque.
NOTICE: When tightening the locknut,
hold the adjusting bolt with a wrench so
that it does not turn together with the lock-
nut.
[ECB00521]
WARNING
EWB02090Operating with improperly serviced or adjust-
ed brakes could cause the brakes to malfunc-
tion, resulting in reduced braking
performance. This could increase the chance
of a collision or accident. After adjusting the
parking brake free play, block the rear of the
ATV off the ground and spin the rear wheels.
Check to make sure there is no brake drag. If
brake drag is noticed, perform the adjustment
again.EBU24740Brake light switches The operation of the brake light switches must be
checked and, if necessary, adjusted at the inter-
vals specified in the periodic maintenance and lu-
brication chart.
The brake light switch for the brake pedal can be
adjusted as follows, but the other brake light
switches should be adjusted by a Yamaha dealer.
1. Locknut
2. Adjusting nut
2
1
(a)(b)
Tightening torque:
Locknut (rear brake caliper):
16 Nm (1.6 m·kgf, 11 ft·lbf)
U1BT60E0.book Page 27 Wednesday, April 15, 2009 1:13 PM