lock YAMAHA YFM350R 2008 User Guide

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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. Install the purging bolt and tighten it 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
Yamaha dealer, who has the necessary profes-
sional knowledge and experience. The adjustment
1. Purging boltTightening torque:
Purging bolt:
27 Nm (2.7 m·kgf, 19 ft·lbf)
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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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8

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.
WARNING
EWB02070Operating with improperly serviced or adjust-
ed brakes could cause loss of braking ability,
which could lead to an accident.
After servicing:
Make sure the brakes operate smoothly and
that the free play is correct.1. Brake lever free play
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EBU24710Adjusting the parking brake free play The parking brake free play must be checked and,
if necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
Cable length “A” should measure 64–68 mm
(2.52–2.68 in). Adjust the parking brake free play
as follows.
1. 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. Loosen the locknut on the brake cable.
4. Turn the adjusting nut on the brake cable in di-
rection (a) to increase the cable length, and in
direction (b) to decrease it.
NOTE:If 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.
1. Locknut
2. Adjusting bolt
3. Cable length “A”
1. Locknut
2. Adjusting nut
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CAUTION:ECB00520When tightening the locknut, hold the adjust-
ing bolt with a wrench so that it does not turntogether with the locknut.
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 adjustmentagain.
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.NOTE:The brake light switch is properly adjusted when
the brake light comes on just before braking takeseffect.
Turn the 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 adjust-
ing nut in direction (b). Tightening torque:
Locknut (rear brake caliper):
16 Nm (1.6 m·kgf, 11 ft·lbf)
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EBU24820Adjusting 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.
The clutch lever free play should measure 5.0–
10.0 mm (0.20–0.39 in) as shown. If the free play
is incorrect, adjust it as follows.1. Loosen the locknut at the clutch lever.
2. To increase the clutch lever free play, turn the
adjusting bolt at the clutch lever in direction
(a), and to decrease it, turn the bolt in direction
(b).
3. Tighten the locknut at the clutch lever.
If the specified free play cannot be obtained,
proceed with the following steps.
4. Loosen the locknut at the clutch lever.
5. Fully turn the adjusting bolt at the clutch lever
in direction (a) to loosen the clutch cable.
6. Loosen the locknut at the crankcase.1. Brake light switch
2. Brake light switch adjusting nut
1. Locknut
2. Clutch lever free play adjusting bolt
3. Clutch lever free play
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8 7. To increase the clutch lever free play, turn the
adjusting nut at the crankcase in direction (a),
and to decrease it, turn the nut in direction (b).
8. Tighten the locknut at the crankcase and the
clutch lever.
NOTE:If the specified free play cannot be obtained as de-
scribed above or if the clutch does not operate cor-
rectly, have a Yamaha dealer check the internalclutch mechanism.
EBU24842Drive chain slack The drive chain slack should be checked before
each ride and adjusted if necessary.
To check the drive chain slack
1. Place the ATV on a level surface.NOTE:When checking and adjusting the drive chain
slack, there should be no weight on the ATV andall tires must be touching the ground.
2. Move the ATV back and forth to locate the
tightest portion of the drive chain, and then
measure the drive chain slack as shown.
1. Locknut
2. Clutch lever free play adjusting nut (crankcase)
Drive chain slack:
25.0–35.0 mm (0.98–1.38 in)
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83. If the drive chain slack is incorrect, adjust it as
follows.
To adjust the drive chain slack
1. Loosen the axle holding bolts.2. Loosen the locknut on each side of the swing-
arm. To tighten the drive chain, turn the ad-
justing 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.
NOTE:There 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
1. Drive chain slack
1. Axle holding bolt (upper)
2. Axle holding bolt (lower)
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8 mark on both drive chain pullers with the alignment
mark on either side of the swingarm for proper
wheel alignment.CAUTION:ECB00541Improper drive chain slack will overload the en-
gine 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 drivechain slack within the specified limits.3. Tighten the locknuts and the axle holding bolts
to the specified torques.
EBU24880Lubricating 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.
1. Locknut
2. Drive chain slack adjusting bolt
3. Alignment marks
Tightening torques:
Locknut:
16 Nm (1.6 m·kgf, 11 ft·lbf)
Axle holding bolt (upper):
120 Nm (12.0 m·kgf, 85 ft·lbf)
Axle holding bolt (lower):
73 Nm (7.3 m·kgf, 53 ft·lbf)
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CAUTION:ECB00640To prevent accidental short-circuiting, turn off
the main switch when checking or replacing afuse.
2. Remove the blown fuse, and then install a
new fuse of the specified amperage.
WARNING
EWB02171Always use a fuse of the specified rating, and
never use a substitute object in place of the
proper fuse. An improper fuse or a substitute
object can cause damage to the electrical sys-tem, which could lead to a fire.
3. Turn the key to “ON” and turn on the electrical
circuits to check if the devices operate.
4. If the fuse immediately blows again, have a
Yamaha dealer check the electrical system.EBU25541Replacing a headlight bulb If a headlight bulb burns out, replace it as follows.1. Remove the headlight bulb holder cover at the
rear of the headlight by pulling it off.
2. Remove the headlight bulb holder by pushing
it inward and turning it counterclockwise. Specified fuse:
15.0 A
1. Headlight bulb holder cover
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