YAMAHA YFM250R 2010 Owners Manual

8-24
8 If the rear brake fluid level is low, replenish as fol-
lows.
1. Remove the brake fluid reservoir cap cover by
removing the bolt.
2. Remove the brake fluid reservoir cap.3. Refill with brake fluid.
4. Install the brake fluid reservoir cap.
5. Install the brake fluid reservoir cap cover by in-
stalling the bolt.
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.
1. Bolt
2. Brake fluid reservoir cap cover
1
2
1. Brake fluid reservoir capRecommended brake fluid:
DOT 4
1
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8

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.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.1. No free play
1
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8 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.
EBU24711Adjusting 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.1. Brake pedal position
1
1. Adjusting bolt
2. Cable length “A”
3. Locknut
2
1 3
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8
TIPIf 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.
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.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.
1. Locknut
2. Adjusting nut
2
1
(a)(b)
Tightening torque:
Locknut (rear brake caliper):
16 Nm (1.6 m·kgf, 11 ft·lbf)
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8
TIPThe brake light switch is properly adjusted when
the brake light comes on just before braking takes
effect.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).
EBU24811Adjusting 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.
1. Brake light switch
2. 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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83. 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 to its original position.
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 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.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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8
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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8
EBU24881Lubricating 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.NOTICEECB00560The 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. 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]
EBU24901
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-
essary. If a cable is damaged or does not move
smoothly, have a Yamaha dealer check or replace
it.
1. O-rings
1
Recommended lubricant:
Engine oil
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8
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 leverRecommended lubricants:
Brake lever:
Silicone grease
Clutch lever:
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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.
EBU24962Checking 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.EBU24994Lubricating the swingarm pivots The swingarm pivots must be lubricated at the in-
tervals specified in the periodic maintenance and
lubrication chart.Recommended lubricant:
Lithium-soap-based grease
Recommended lubricant:
Lithium-soap-based grease
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