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8-20
8
7. Start the engine and rev it up approximately
twenty times while momentarily creating ex-
haust system back pressure by blocking the
end of the muffler with a shop towel.
8. Stop the engine and allow the exhaust pipe to cool.
9. Check the gasket for damage, and replace it if necessary.
10. Install the gasket and the purging bolt, and then tighten the bolt to the specified torque.
WARNING
EWB02380Never run the engine in an enclosed area when
purging the spark arrester, otherwise it could
cause injury to the eyes, burns, carbon monox-
ide poisoning, possibly leading to death, and
start a fire.●Always let the exhaust system cool prior to
touching exhaust components.●Always wear eye protection, and make sure
no one is behind the ATV.●Make sure there are no combustible materi-
als in the area.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
1. Purging bolt
2. Gasket
12
Tightening torque:Purging bolt:27 Nm (2.7 m·kgf, 20 ft·lbf)
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8-27
81. Release the parking brake by moving the
parking brake lever to the right.
2. Fully loosen the locknut and the adjusting bolt at the rear brake caliper.
3. Slide the rubber cover back at the brake ca- ble.
4. Loosen the locknut.
5. Turn the parking brake free play adjusting nut in direction (a) to increase the cable length,
and in direction (b) to decrease it.
TIPIf the cable length cannot be adjusted to specifica-
tion, consult a Yamaha dealer.6. Tighten the locknut on the brake cable.
7. Slide the rubber cover to its original position.
8. 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,
1. Locknut
2. Adjusting bolt
3. Cable length “A”
1. Locknut
2. Parking brake free play adjusting nut
3. Rubber cover
1
2
(a) (b)
3
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![YAMAHA YFM350R 2013 Owners Manual 8-28
8
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 b YAMAHA YFM350R 2013 Owners Manual 8-28
8
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 b](/manual-img/51/53698/w960_53698-108.png)
8-28
8
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.EBU24743Brake light switches The brake light, which is activated by the brake
pedal and brake lever, should come on just before
braking takes effect. The brake light switch for the brake pedal can be
adjusted as follows, but the front brake light switch
should be adjusted by a Yamaha dealer.
Turn the rear brake light switch adjusting nut while
holding the brake light switch in place. To make the
brake light come on earlier, turn the adjusting nut
in direction (a). To make the brake light come on
later, turn the adjusting nut in direction (b).
EBU30120Adjusting the clutch lever free play The clutch lever free play must be checked and, if
necessary, adjusted at the intervals specified in the
periodic maintenance and lubrication chart.
Tightening torque:
Locknut (rear brake caliper):16 Nm (1.6 m·kgf, 12 ft·lbf)1. Rear brake light switch
2. Rear brake light switch adjusting nut
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8-31
83. Loosen the locknut on each side of the swing-
arm. To tighten the drive chain, turn the drive
chain slack adjusting bolts in direction (a). To
loosen the drive chain, turn the adjusting bolts
in direction (b) and push the wheels forward.
Turn each adjusting bolt exactly the same
amount to maintain correct axle alignment.
NOTICE: Improper drive chain slack will
overload the engine as well as other vital
parts of the ATV and can lead to drive
chain slippage or breakage. To prevent
this from occurring, keep the drive chain
slack within the specified limits.
[ECB00542]
TIPThere are alignment marks on both drive chain
pullers and an alignment mark on each side of the
swingarm. Make sure to align the same alignment
mark on both drive chain pullers with the alignment
mark on either side of the swingarm for proper
wheel alignment.4. Tighten the locknuts and the axle holding bolts to the specified torques.
1. Axle holding bolt (upper)
2. Axle holding bolt (lower)
1. Locknut
2. Drive chain slack adjusting bolt
3. Alignment marks
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8-32
8
EBU24882Lubricating the drive chain The drive chain must be cleaned and lubricated at
the intervals specified in the periodic maintenance
and lubrication chart, otherwise it will quickly wear
out, especially when riding in dusty or wet areas.
Service the drive chain as follows.NOTICEECB00561The drive chain must be lubricated after wash-
ing the ATV or riding in the rain or wet areas.1. Clean the drive chain with kerosene and asmall soft brush. NOTICE: To prevent dam-
aging the O-rings, do not clean the drive
chain with steam cleaners, high-pressure
washers or inappropriate solvents.
[ECB00571]
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive chain with a special O-ring chain lubricant. NOTICE: Do
not use engine oil or any other lubricants
for the drive chain, as they may contain
substances that could damage the O-
rings.
[ECB00581]
EBU24902
Checking and lubri cating the cables The operation and the condition of all control ca-
bles should be checked before each ride, and the
cables and cable ends should be lubricated if nec-
Tightening torques:
Locknut:16 Nm (1.6 m·kgf, 12 ft·lbf)
Axle holding bolt (upper): 120 Nm (12 m·kgf, 87 ft·lbf)
Axle holding bolt (lower): 73 Nm (7.3 m·kgf, 53 ft·lbf)1. O-ring
1
1
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8-44
8
3. Insert a new bulb into the socket, push it in,
and then turn it clockwise until it stops.
4. Install the lens by installing the screws. NOTICE: Do not overtighten the screws,
otherwise the lens may break.
[ECB00701]
EBU25651
Removing a wheel 1. Place the ATV on a level surface.
2. Loosen the wheel nuts. 3. Elevate the ATV and place a suitable stand
under the frame.
4. Remove the nuts from the wheel.
5. Remove the wheel.
EBU25661Installing a wheel 1. Place the ATV on a level surface.
2. Install the wheel and the nuts.
3. Lower the ATV to the ground.
4. Tighten the wheel nuts to the specified torques.
1. Tail/brake light bulb
1. Wheel nut
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8-45
8
EBU25720Troubleshooting Although Yamaha ATVs receive a thorough in-
spection before shipment from the factory, trouble
may occur during operation. Any problem in the fu-
el, compression, or ignition systems, for example,
can cause poor starting and loss of power.
The following troubleshooting chart represents a
quick and easy procedure for checking these vital
systems yourself. However, should your ATV re-
quire any repair, take it to a Yamaha dealer, whose
skilled technicians have the necessary tools, expe-
rience, and know-how to service the ATV properly.
Use only genuine Yamaha replacement parts. Im-
itation parts may look like Yamaha parts, but they
are often inferior, have a shorter service life and
can lead to expensive repair bills.
WARNING
EWB02280Do not smoke when checking the fuel system.
Fuel can ignite or explode, causing severe inju-
ry or property damage. Make sure there are no
open flames or sparks in the area, including pi-
lot lights from water heaters or furnaces.
Tightening torques:Front wheel nut:45 Nm (4.5 m·kgf, 33 ft·lbf)
Rear wheel nut: 45 Nm (4.5 m·kgf, 33 ft·lbf)
U1BS63E0.book Page 45 Tuesday, March 13, 2012 11:43 AM