2011 YAMAHA YFM350R engine

8-7
8
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*Rear suspension re-
lay arm and con-
necting arm
pivoting pointsCheck operation and correct if necessary.
Lubricate with lithium-soap-based grease.√√√√
17*Steering shaftLubricate with lithium-soap-based grease.√√√
18*Steering systemCheck operation and repair or replace if damaged.
Check toe-in and adjust if necessary.√√√√√
19 Engine oilChange.
Check ATV for oil leakage, and correct if neces-
sary.√ √√√
20Engine oil filter ele-
mentClean or replace if necessary.√√√
21 Engine oil strainerClean.√√√
22*Moving parts and
cablesLubricate.√√√√ 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 320U1BS61E0.book Page 7 Tuesday, April 13, 2010 10:25 AM

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EBU23213Checking 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).1. Spark plug cap
1. Spark plug wrench
U1BS61E0.book Page 9 Tuesday, April 13, 2010 10:25 AM

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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.2. 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. Specified spark plug:
NGK/DR8EA
1. Spark plug gapSpark plug gap:
0.6–0.7 mm (0.024–0.028 in)
U1BS61E0.book Page 10 Tuesday, April 13, 2010 10:25 AM

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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.EBU2327DEngine 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 cleaned at the intervals speci-
fied in the periodic maintenance and lubrication
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.
Tightening torque:
Spark plug:
18 Nm (1.8 m·kgf, 13 ft·lbf)
U1BS61E0.book Page 11 Tuesday, April 13, 2010 10:25 AM

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5. 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 cleaning)
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. NOTICE: When remov-
ing the engine oil drain bolt, the compres-
sion spring, oil strainer and O-ring will fall
out. Take care not to lose these parts.
[ECB00311]
1. Engine oil dipstick
2. Maximum level mark
3. Minimum level mark
4. Engine oil filler capU1BS61E0.book Page 12 Tuesday, April 13, 2010 10:25 AM

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TIPSkip steps 5–8 if the oil filter element is not being
cleaned.5. Remove the oil filter element cover by remov-
ing the bolts, and then remove the oil filter el-
ement and the O-ring.6. Clean the oil strainer and oil filter element with
solvent.
7. Install the oil filter element and a new O-ring.
TIPMake sure that the O-ring is properly seated.8. Install the oil filter element cover by installing
the bolts, and then tighten them to the speci-
fied torque.
1. Engine oil drain bolt
2. O-ring
3. Compression spring
4. Oil strainer
1. Oil filter element cover
2. Bolt
3. Oil filter element
4. O-ring
U1BS61E0.book Page 13 Tuesday, April 13, 2010 10:25 AM

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89. Install the oil strainer, the compression spring,
a new O-ring and the engine oil drain bolt.
Tighten the engine oil drain bolt to the speci-
fied torque. NOTICE: Before installing the
engine oil drain bolt, be sure to install the
O-ring, compression spring and oil strain-
er.
[ECB00321]
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.
Tightening torque:
Oil filter element cover bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Tightening torque:
Engine oil drain bolt:
32 Nm (3.2 m·kgf, 23 ft·lbf)
Recommended oil:
See page 10-1.
Oil quantity:
Without oil filter element replacement:
2.50 L (2.64 US qt, 2.20 Imp.qt)
With oil filter element replacement:
2.60 L (2.75 US qt, 2.29 Imp.qt)
U1BS61E0.book Page 14 Tuesday, April 13, 2010 10:25 AM

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8 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.
EBU23743Cleaning 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.TIPThere is a check hose at the bottom of the air filter
case. If dust or water collects in this hose, empty
the hose and clean the air filter element and air fil-
ter case.
1. Place the ATV on a level surface.
2. Remove the seat. (See page 4-12.)
3. Remove the air filter case cover by unhooking
the holders.1. Air filter case check hose
U1BS61E0.book Page 15 Tuesday, April 13, 2010 10:25 AM