YAMAHA YFM350R 2008 Owners Manual

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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 brakeRear brake
Observe 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.
1. Minimum level mark
1. Minimum level markRecommended brake fluid:
DOT 4
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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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Make sure the brakes do not drag.
Make sure the brakes are not spongy. All air
must be bled from the brake system.
Replacement of brake components requires
professional knowledge. These proceduresshould be performed by a Yamaha dealer.EBU24591Checking the brake pedal position The brake pedal position must be checked and, if
necessary, adjusted at the intervals specified in the
periodic maintenance and lubrication chart.
The top of the brake pedal should be positioned
50.2 mm (1.98 in) above the top of the frame as
shown. If the brake pedal is not positioned as spec-
ified, have a Yamaha dealer adjust it.
WARNING
EWB02110Operating 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 brake pedal position is correct.
Make sure the brakes do not drag.
Make sure the brakes are not spongy. All air
must be bled from the brake system.
Replacement of brake components requires
professional knowledge. These proceduresshould be performed by a Yamaha dealer.1. Brake pedal position
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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:ECB00560The drive chain must be lubricated after wash-ing the ATV or riding in the rain.
1. Clean the drive chain with kerosene and a
small soft brush.CAUTION:ECB00570To prevent damaging the O-rings, do not clean
the drive chain with steam cleaners, high-pres-sure washers or inappropriate solvents.
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive chain with a
special O-ring chain lubricant.
CAUTION:ECB00580Do not use engine oil or any other lubricants
for the drive chain, as they may contain sub-stances that could damage the O-rings.EBU24900Checking and lubricating 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-
essary. If a cable is damaged or does not move
smoothly, have a Yamaha dealer check or replace
it.
WARNING
EWB02130Inspect cables frequently and replace if dam-
aged. Corrosion can result when the cable
sheaths become damaged, and cables can
also become frayed or kinked, which could re-
strict the operation of controls and lead to anaccident or injury.
1. O-ring
Recommended lubricant:
Engine oil
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