YAMAHA YFM350R 2011 Owners Manual

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TIPThe engine is warm when it quickly responds to the
throttle.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).
TIPIf the specified idling speed cannot be obtained as
described above, have a Yamaha dealer make the
adjustment.EBU24045Adjusting 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.TIPThe engine idling speed must be checked, and ad-
justed if necessary, before adjusting the throttle ca-
ble free play.1. Slide the rubber cover back.
2. Loosen the locknut.
3. To increase the throttle cable free play, turn
the throttle cable free play adjusting bolt in di-
rection (a). To decrease the throttle cable free
play, turn the adjusting bolt in direction (b).
1. Throttle stop screwEngine idling speed:
1450–1550 r/min
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84. Tighten the locknut.
5. Slide the rubber cover to its original position.
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.
EBU29601Brakes Replacement of brake components requires pro-
fessional knowledge. Brake service should be per-
formed by a Yamaha dealer.
WARNING
EWB02571Operating with improperly serviced or adjust-
ed brakes could lead to a loss in braking ability
and an accident.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.EBU28790Front brake pads
Each brake pad is provided with two wear indicator
grooves, which allow you to check the brake pad
wear without having to disassemble the brake. To
check the brake pad wear, check the wear indica-
tor grooves. If a brake pad has worn to the point
that a wear indicator groove almost appears, have
a Yamaha dealer replace the brake pads as a set.
1. Rubber cover
2. Throttle cable free play adjusting bolt
3. Locknut
4. Throttle cable free play
3
12
4
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TIPThe wheels need to be removed to check the
brake pads. (See page 8-43.)EBU28800Rear brake pads
Each brake pad is provided with two wear indicator
grooves, which allow you to check the brake pad
wear without having to disassemble the brake. To
check the brake pad wear, check the wear indica-
tor grooves. If a brake pad has worn to the point
that a wear indicator groove almost appears, have
a Yamaha dealer replace the brake pads as a set.
EBU29840Checking 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.
1. Wear indicator groove
1. Wear indicator groove
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8Front brake
Rear brakeObserve 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.
1. Minimum level mark
1. Minimum level mark
1
Recommended brake fluid:
DOT 4
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EBU24291Changing the brake fluid Have a Yamaha dealer change the brake fluid at
the intervals specified in the TIP after the periodic
maintenance and lubrication chart. In addition,
have the oil seals of the master cylinders and cali-
pers as well as the brake hoses replaced at the in-
tervals listed below or whenever they are damaged
or leaking.
Oil seals: Replace every two years.
Brake hoses: Replace every four years.EBU24394Checking 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 no
free play as shown. If there is free play, have a
Yamaha dealer check the brake system.
EBU24592Checking 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.1. No brake lever free play
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EBU24712Adjusting 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. Slide the rubber cover back.
4. Loosen the locknut on the brake cable.
5. Turn the adjusting nut on the brake cable in di-
rection (a) to increase the cable length, and in
direction (b) to decrease it.1. Brake pedal position
1. Locknut
2. Adjusting bolt
3. Cable length “A”
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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,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.EBU24742Brake light switches The brake light, which is activated by the brake
pedal and brake lever, should come on just before
braking takes effect.
1. Locknut
2. Adjusting nut
3. Rubber cover
1
2
(a)(b)
3
Tightening torque:
Locknut (rear brake caliper):
16 Nm (1.6 m·kgf, 12 ft·lbf)
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8The 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 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).
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.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. Slide the rubber cover back at the clutch lever.
2. Loosen the locknut.
3. 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).1. Rear brake light switch
2. Rear brake light switch adjusting nut
1. Clutch lever free play
2. Rubber cover
3. Locknut
4. Clutch lever free play adjusting bolt
3 2
4 (a) (b)
1
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TIPIf the specified clutch lever free play could be ob-
tained as described above, skip steps 4–8.4. Fully turn the adjusting bolt at the clutch lever
in direction (a) to loosen the clutch cable.
5. Slide the rubber cover back at the crankcase.
6. Loosen the locknut.
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 then
slide the rubber cover to its original position.
9. Tighten the locknut at the clutch lever, and
then slide the rubber cover to its original posi-
tion.
TIPIf 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 internal
clutch mechanism.EBU24844Drive 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.TIPWhen checking and adjusting the drive chain
slack, there should be no weight on the ATV and
all 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)
3. Rubber cover
2
(a)
(b)
3
1
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3. If the drive chain slack is incorrect, adjust it as
follows.
To adjust the drive chain slack
1. Place the ATV on a level surface.
2. Loosen the axle holding bolts.3. 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. NOTICE: Im-
proper 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 occur-
ring, keep the drive chain slack within the
specified limits.
[ECB00542]
Drive chain slack:
25.0–35.0 mm (0.98–1.38 in)1. Drive chain slack
1. Axle holding bolt (upper)
2. Axle holding bolt (lower)
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