2010 YAMAHA YFM250R engine

8-6
8
9*Wheel hub bearingsCheck for looseness or damage, and replace if
necessary.√ √√√
10*Swingarm pivotsCheck operation and for excessive play, and re-
place bearings if necessary.
Lubricate with lithium-soap-based grease.√√√
11*Upper and lower
arm pivotsLubricate with lithium-soap-based grease.√√√
12 Drive chainCheck chain slack and adjust if necessary.
Check rear wheel alignment and correct if neces-
sary.
Clean and lubricate.√√√√√
13*Drive chain rollerCheck for wear and replace if necessary.√√√
14*Chassis fastenersMake sure that all nuts, bolts, and screws are
properly tightened.√√√√√
15*Shock absorber as-
sembliesCheck operation and correct if necessary.
Check for oil leakage and replace if necessary.√√√
16*Steering shaftLubricate with lithium-soap-based grease.√√√
17*Steering systemCheck operation and repair or replace if damaged.
Check toe-in and adjust if necessary.√√√√√
18 Engine oilChange.
Check ATV for oil leakage, and correct if neces-
sary.√ √√√
19Engine oil filter ele-
mentReplace.√√√ NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth136612
km
(mi)320
(200)1300
(800)2500
(1600)2500
(1600)5000
(3200)
hours 20 80 160 160 320
U1BT60E0.book Page 6 Wednesday, April 15, 2009 1:13 PM

8-8
8
EBU23211Checking the spark plug The spark plug is an important engine component,
which is easy to check. Since heat and deposits
will cause any spark plug to slowly erode, the spark
plug should be removed and checked in accor-
dance with the periodic maintenance and lubrica-
tion chart. In addition, the condition of the spark
plug can reveal the condition of the engine.
To remove the spark plug
1. Remove the spark plug cap.2. Remove the spark plug as shown, with the
spark plug wrench included in the owner’s tool
kit.
To check the spark plug
1. Check that the porcelain insulator around the
center electrode of the spark plug is a medi-
um-to-light tan (the ideal color when the ATV
is ridden normally).
TIPIf the spark plug shows a distinctly different color,
the engine could be operating improperly. Do not
attempt to diagnose such problems yourself. In-
stead, have a Yamaha dealer check the ATV.
1. Spark plug cap
1
1. Spark plug wrench
1
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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
U1BT60E0.book Page 10 Wednesday, April 15, 2009 1:13 PM

8-11
85. If the engine oil is at or below the minimum
level mark, add sufficient oil of the recom-
mended type to raise it to the correct level.
NOTICE: Be sure the engine oil is at the
correct level, otherwise engine damage
may result.
[ECB00851]
6. Insert the dipstick into the oil filler hole, and
then tighten the engine oil filler cap.
To change the engine oil (with or without oil fil-
ter element replacement)
1. Place the ATV on a level surface.
2. Start the engine, warm it up for several min-
utes, and then turn it off.
3. Place an oil pan under the engine to collect
the used oil.
4. Remove the engine oil filler cap, and then re-
move the engine oil drain bolt to drain the oil
from the crankcase.
TIPSkip steps 5–8 if the oil filter element is not being
replaced.5. Remove the oil filter element cover by remov-
ing the bolts, and then remove the oil filter el-
ement.1. Engine oil drain bolt
1
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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)
U1BT60E0.book Page 13 Wednesday, April 15, 2009 1:13 PM

8-15
86. Remove the wing bolt and washer from the air
filter element.
7. Remove the sponge material from the air filter
element frame.8. Wash the sponge material gently but thor-
oughly in solvent. WARNING! Always use
parts cleaning solvent to clean the sponge
material. Never use low-flash-point sol-
vents or gasoline to clean the sponge ma-
terial because the engine could catch fire
or explode.
[EWB01941]
9. Squeeze the excess solvent out of the sponge
material and let it dry. NOTICE: Do not twist
the sponge material when squeezing it.
[ECB00441]
1. Wing bolt
2. Air filter element
3. Washer
1 2
3
1. Sponge material
2. Air filter element frame
1
2
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8-17
815. Insert the air filter element into the air filter
case, and then tighten the wing bolt. NOTICE:
Make sure that the air filter element is
properly seated in the air filter case. Never
operate the engine with the air filter ele-
ment removed. This will allow unfiltered air
to enter the engine, causing rapid engine
wear and possible engine damage. Addi-
tionally, operation without the air filter ele-
ment will affect carburetor jetting with
subsequent poor performance and possi-
ble engine overheating.
[ECB00461]
16. Install the air filter case cover by hooking the
holders onto the air filter case.17. Install the seat.
TIPThe air filter element should be cleaned every 20–
40 hours. It should be cleaned and lubricated more
often if the ATV is operated in extremely dusty ar-
eas. Each time the air filter element maintenance
is performed, check the air inlet of the air filter case
for obstructions. Check the air filter case rubber
joint to the carburetor fittings and the rubber joint
manifold fittings for an air-tight seal. Tighten all fit-
tings securely to avoid the possibility of unfiltered
air entering the engine.EBU28901Cleaning the spark arrester Be sure the exhaust pipe and muffler are cool be-
fore cleaning the spark arrester.
1. Remove the bolts.
1. Washer
1
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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
U1BT60E0.book Page 19 Wednesday, April 15, 2009 1:13 PM