YAMAHA YFM250R 2008 Owners Manual
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EBU24130
Checking 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.
EBU27711
Front brake pads
Each brake pad is provided with 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 the wear indicator grooves are almost in con-
tact with the disc plate, have a Yamaha dealer re-
place the brake pads as a set.
NOTE:
The wheels need to be removed to check the
brake pads. (See page 8-42.)
EBU24190
Rear brake pads
Each brake pad is provided with a wear indicator,
which allows you to check the brake pad wear
without having to disassemble the brake. To check
the brake pad wear, check the position of the wear
indicator while applying the brake. If a brake pad
has worn to the point that the wear indicator almost
touches the brake disc, have a Yamaha dealer re-
1. Wear indicator groove
1
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place the brake pads as a set.
EBU28930
Checking 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 brake
1. Wear indicator
1
1. Minimum level mark1
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Rear brake
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.
1. Minimum level mark
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1. Bolt
2. Brake fluid reservoir cap cover
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2
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3. Refill with brake fluid.
4. Install the brake fluid reservoir cap.
5. Install the brake fluid reservoir cap cover by
installing 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.
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.
EBU24290
Changing 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.
1. Brake fluid reservoir cap
Recommended brake fluid:
DOT 4
1
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EBU24390
Checking 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
EWB02070
Operating 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.
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 procedures
should be performed by a Yamaha dealer.
EBU24591
Checking 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
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.
1. Brake lever free play
1
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WARNING
EWB02110
Operating 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 procedures
should be performed by a Yamaha dealer.
EBU24710
Adjusting 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
(2.52–2.60 in). Adjust the parking brake free play
as follows.
1. Release the parking brake by moving the
1. Brake pedal position
1
1. Adjusting bolt
2. Cable length “A”
3. Locknut
2
1 3
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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.CAUTION:
ECB00520
When tightening the locknut, hold the adjust-
ing bolt with a wrench so that it does not turn
together with the locknut.WARNING
EWB02090
Operating 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.
1. Locknut
2. Adjusting nut
2
1
(a)(b)
Tightening torque:
Locknut (rear brake caliper):
16 Nm (1.6 m·kgf, 11.6 ft·lbf)
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EBU24740
Brake 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 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).
EBU24810
Adjusting 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. Brake light switch
2. Brake light switch adjusting nut
12
(b)
(a)
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1. Loosen the locknut at the clutch lever.
2. To increase the clutch lever free play, turn the
adjusting bolt in direction (a), and to decrease
it, turn the bolt in direction (b).
3. Tighten the locknut.
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 internal
clutch mechanism.
EBU26861
Drive 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 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. Clutch lever free play
2. Clutch lever free play adjusting bolt
3. Locknut
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2
(a)(b) 3
Drive chain slack:
45.0–55.0 mm (1.77–2.17 in)
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3. If the drive chain slack is incorrect, adjust it as
follows.
To adjust the drive chain slack
1. Loosen the rear axle pinch bolts.
2. 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.NOTE:
A rod can be obtained at a Yamaha dealer to make
this adjustment.
3. Shift the transmission into neutral.
4. To tighten the drive chain, push the ATV back-
ward. To loosen the drive chain, push the ATV
forward.
CAUTION:
ECB00541
Improper drive chain slack will overload the en-
1. Drive chain slack
1
1. Rear wheel axle pinch bolt
2. Rod
3. Drive chain tensioner
4. Hole
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