YAMAHA YFM350R-W 2010 Owners Manual

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CAUTION:ECB00300
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 thecrankcase.
12. 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.
13. Turn the engine off, and then check the oil lev-
el and correct it if necessary.
EBU23740Cleaning the air filter element The air filter element should be cleaned at the in-
tervals specified in the periodic maintenance and
lubrication chart. Clean the air filter element more
frequently if you are riding in unusually wet or dusty
areas.NOTE:There 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. Remove the seat. (See page 4-14.) 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)1. Air filter case check hose
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8-14
82. Remove the air filter case cover by unhooking
the holders.
3. Pull the air filter element out of the air filter
case.4. Remove the sponge material from the air filter
element frame.
1. Air filter case cover
2. Air filter case holder
1. Air filter element assembly
1. Unlock.
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5. Wash the sponge material gently but thor-
oughly in solvent.
WARNING
EWB01940Always use parts cleaning solvent to clean the
sponge material. Never use low-flash-point
solvents or gasoline to clean the sponge mate-
rial because the engine could catch fire or ex-plode.
6. Squeeze the excess solvent out of the sponge
material and let it dry.
CAUTION:ECB00440Do not twist the sponge material when squeez-ing it.
7. Check the sponge material and replace it if
damaged.
8. Apply a quality foam air filter oil to the sponge
material.NOTE:The sponge material should be wet but not drip-ping.
9. Pull the sponge material over the air filter ele-
ment frame.
10. Apply all-purpose grease to the air filter ele-
ment seat.
11. Insert the air filter element into the air filter
case, and then install the air filter case cover
by hooking the holders onto the air filter case.
12. Install the seat.NOTE:The 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
1. Air filter element retaining plate
2. Air filter element frame
3. Sponge material
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8for 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.CAUTION:ECB00460
Make sure that the air filter element is prop-
erly seated in the air filter case.
Never operate the engine with the air filter el-
ement removed. This will allow unfiltered air
to enter the engine, causing rapid engine
wear and possible engine damage. Addition-
ally, operation without the air filter element
will affect carburetor jetting with subsequent
poor performance and possible engine over-heating.EBU27490Cleaning the spark arrester Be sure the exhaust pipe and muffler are cool be-
fore cleaning the spark arrester.
1. Remove the bolt.2. Remove the tailpipe by pulling it out of the
muffler.
3. Tap the tailpipe lightly, and then use a wire
brush to remove any carbon deposits from the
spark arrester portion of the tailpipe and inside
of the tailpipe housing.
1. Bolt
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8 4. Insert the tailpipe into the muffler and align the
bolt holes.
5. Install and tighten the bolt.
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 totouching 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.CAUTION:ECB00480The 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 ordamage to the engine.EBU24000Adjusting the engine idling speed The engine idling speed must be checked and, if
necessary, adjusted as follows at the intervals
specified in the periodic maintenance and lubrica-
tion chart.
1. Tailpipe
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NOTE:A diagnostic tachometer is needed to make thisadjustment.
1. Start the engine and warm it up.NOTE:The engine is warm when it quickly responds to thethrottle.
2. Attach the tachometer to the spark plug lead.
3. Check the engine idling speed and, if neces-
sary, adjust it to specification by turning the
throttle stop screw at the carburetor. To in-
crease the engine idling speed, turn the throt-
tle stop screw in direction (a), and to decrease
it, turn the screw in direction (b).
NOTE:If the specified idling speed cannot be obtained as
described above, have a Yamaha dealer make theadjustment.1. Throttle stop screwEngine idling speed:
1450–1550 r/min
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EBU24043Adjusting the throttle cable free play The throttle cable free play should be checked
and, if necessary, adjusted at the intervals speci-
fied in the periodic maintenance and lubrication
chart.
The throttle cable free play should measure 2.0–
4.0 mm (0.08–0.16 in) at the throttle lever. Period-
ically check the throttle cable free play and, if nec-
essary, adjust it as follows.NOTE:The engine idling speed must be checked, and ad-
justed if necessary, before adjusting the throttle ca-ble free play.
1. Loosen the locknut.
2. To increase the throttle cable free play, turn
the adjusting bolt in direction (a). To decrease
the throttle cable free play, turn the adjusting
bolt in direction (b).3. Tighten the locknut.
EBU24060Valve clearance The valve clearance changes with use, resulting in
improper air-fuel mixture and/or engine noise. To
prevent this from occurring, the valve clearance
must be adjusted by a Yamaha dealer at the inter-
vals specified in the periodic maintenance and lu-
brication chart.1. Locknut
2. Throttle cable free play adjusting bolt
3. Throttle cable free play
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EBU24130Checking the front and rear brake pads The front and rear brake pads must be checked for
wear at the intervals specified in the periodic main-
tenance and lubrication chart.EBU24150Front brake pads
Each brake pad is provided with a wear indicator
groove, which allows you to check the brake pad
wear without having to disassemble the brake. To
check the brake pad wear, check the wear indica-
tor groove. If a brake pad has worn to the point that
the wear indicator groove is almost in contact with
the disc plate, have a Yamaha dealer replace the
brake pads as a set.
NOTE:The wheels need to be removed to check thebrake pads. (See page 8-40.)EBU24200Rear brake pads
Each brake pad is provided with a wear indicator
groove, which allows you to check the brake pad
wear without having to disassemble the brake. To
check the brake pad wear, check the wear indica-
tor groove. If a brake pad has worn to the point that
the wear indicator groove is almost in contact with
the disc plate, have a Yamaha dealer replace the
brake pads as a set.1. Wear indicator groove
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EBU24251Checking the brake fluid level Insufficient brake fluid may allow air to enter the
brake system, possibly causing it to become inef-
fective.
Before riding, check that the brake fluid is above
the minimum level mark and replenish if neces-
sary. A low brake fluid level may indicate worn
brake pads and/or brake system leakage. If the
brake fluid level is low, be sure to check the brake
pads for wear and the brake system for leakage.Front brake
Rear brake1. Wear indicator groove
1. Minimum level mark
1. Minimum level mark
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8Observe these precautions:

When checking the fluid level, make sure that
the top of the brake fluid reservoir is level.
Use only the recommended quality brake fluid,
otherwise the rubber seals may deteriorate,
causing leakage and poor braking performance.
Refill with the same type of brake fluid. Mixing
fluids may result in a harmful chemical reaction
and lead to poor braking performance.
Be careful that water does not enter the brake
fluid reservoir when refilling. Water will signifi-
cantly lower the boiling point of the fluid and may
result in vapor lock.
Brake fluid may deteriorate painted surfaces or
plastic parts. Always clean up spilled fluid imme-
diately.
As the brake pads wear, it is normal for the brake
fluid level to gradually go down. However, if the
brake fluid level goes down suddenly, have a
Yamaha dealer check the cause.
EBU24290Changing the brake fluid Have a Yamaha dealer change the brake fluid at
the intervals specified in the NOTE after the peri-
odic maintenance and lubrication chart. In addi-
tion, have the oil seals of the master cylinders and
calipers as well as the brake hoses replaced at the
intervals listed below or whenever they are dam-
aged or leaking.
Oil seals: Replace every two years.
Brake hoses: Replace every four years.EBU24390Checking the front brake lever free play The brake lever free play must be checked at the
intervals specified in the periodic maintenance and
lubrication chart. The brake lever should have a
free play of zero mm (zero in) as shown. If the free
play is incorrect, have a Yamaha dealer check the
brake system. Recommended brake fluid:
DOT 4
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