YAMAHA YFM250R 2012 Owners Manual

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Front brake
Rear brake
WARNING
EWB02720Improper maintenance can result in loss of
braking ability. Observe these precautions:
Insufficient brake fluid may allow air to enter
the brake system, reducing braking perfor-
mance.
Clean the filler cap before removing. Use
only DOT 4 brake fluid from a sealed contain-
er.
Use only the specified brake fluid; otherwise,
the rubber seals may deteriorate, causing
leakage.
Refill with the same type of brake fluid. Add-
ing a brake fluid other than DOT 4 may result
in a harmful chemical reaction.
Be careful that water does not enter the
brake fluid reservoir when refilling. Water
will significantly lower the boiling point of
the fluid and may result in vapor lock.
1. Minimum level mark
1. Minimum level mark
1
1
Specified brake fluid:
DOT 4
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NOTICEECB01160Brake fluid may damage painted surfaces or
plastic parts. Always clean up spilled fluid im-
mediately.As the brake pads wear, it is normal for the brake
fluid level to gradually go down. A low brake fluid
level may indicate worn brake pads and/or brake
system leakage; therefore, be sure to check the
brake pads for wear and the brake system for leak-
age. If the brake fluid level goes down suddenly,
have a Yamaha dealer check the cause before fur-
ther riding.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.EBU24593Checking the brake pedal height The brake pedal height must be checked and, if
necessary, adjusted at the intervals specified in the
periodic maintenance and lubrication chart.1. No brake lever free play
1
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The top of the brake pedal should be positioned
40.0 mm (1.57 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.
EBU24713Adjusting 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 at the brake ca- ble.
4. Loosen the locknut.
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 height
1
1. Cable length “A”
2. Locknut
3. Adjusting bolt
1
3
2
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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.EBU24743Brake light switches The brake light, which is activated by the brake
pedal and brake lever, should come on just before
braking takes effect.
1. Rubber cover
2. Adjusting nut
3. Locknut
2
3
1(a) (b)
Tightening torque:
Locknut (rear brake caliper):16 Nm (1.6 m ·kgf, 12 ft· lbf)
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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).
EBU24812Adjusting 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.
2. Loosen the locknut at the clutch lever.
3. To increase the clutch lever free play, turn the adjusting bolt in direction (a), and to decrease
it, turn the bolt in direction (b).
4. Tighten the locknut.
5. Slide the rubber cover back to its original po- sition.1. Rear brake light switch
2. Rear brake light switch adjusting nut
12
(b)
(a)
1. Clutch lever free play
2. Locknut
3. Clutch lever free play adjusting bolt
4. Rubber cover1
3
4
(a)
(b)
2
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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.EBU26864Drive chain slack The drive chain slack should be checked before
each ride and adjusted if necessary.
To check the drive chain slack1. 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. 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 rear wheel axle pinch bolts.
3. Insert a rod of a diameter of 8 mm (0.3 in) and a length of 10 cm (4 in) into one of the holes in
the drive chain tensioner as shown.
Drive chain slack: 45.0 –55.0 mm (1.77 –2.17 in)
1. Drive chain slack
1
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TIPA rod can be obtained at a Yamaha dealer to make
this adjustment.4. Shift the transmission into neutral.
5. To tighten the drive chain, push the ATV back-ward. To loosen the drive chain, push the ATV
forward. 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 pre- vent this from occurring, keep the drive
chain slack within the specified limits.
[ECB00542]
6. Pull the rod out, and then tighten the rear axle
pinch bolts to the specified torque in the order
shown.
1. Rear wheel axle pinch bolt
2. Rod
3. Drive chain tensioner
4. Hole
2 11
3
4
Tightening torque:
Rear axle pinch bolt:21 Nm (2.1 m ·kgf, 15 ft ·lbf)
12 34
56 78
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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 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-1. O-rings
1
1
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essary. If a cable is damaged or does not move
smoothly, have a Yamaha dealer check or replace
it.
WARNING
EWB02581
Inspect 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
restrict the operation of controls and lead to
an accident or injury.
Always make sure all control cables work
smoothly before you begin riding in cold
weather. If the control cables are frozen or do
not work smoothly, you could be unable to
control the ATV, which could lead to an acci-
dent or collision.
EBU24922Checking and lubricating the brake and
clutch levers The operation of the brake and clutch levers
should be checked before each ride, and the lever
pivots should be lubricated if necessary.
Brake lever
Recommended lubricant:
Yamaha Chain and Cable Lube or engine oilRecommended lubricants:Brake lever:Silicone grease
Clutch lever: Lithium-soap-based grease
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8Clutch lever
EBUM0170Checking the shift pedal The operation of the shift pedal should be checked
before each ride. If operation is not smooth, have
a Yamaha dealer check the vehicle.EBU28871Checking and lubricating the brake
pedal The operation of the brake pedal should be
checked before each ride, and the pedal pivot
should be lubricated if necessary.
EBU24963Checking the wheel hub bearings The front and rear wheel hub bearings must be
checked at the intervals specified in the periodic
maintenance and lubrication chart. If there is play
in a wheel hub or if a wheel does not turn smoothly,
have a Yamaha dealer check the wheel hub bear-
ings.Recommended lubricant:
Lithium-soap-based grease
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