YAMAHA YFM250R-W 2009 Owners Manual

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EBU24000Adjusting the engine idling speed The engine idling speed must be checked and, if
necessary, adjusted as follows at the intervals
specified in the periodic maintenance and lubrica-
tion chart.TIPA diagnostic tachometer is needed to make thisadjustment.
1. Start the engine and warm it up.TIPThe engine is warm when it quickly responds to thethrottle.
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 theadjustment.1. Throttle stop screwEngine idling speed:
1500–1600 r/min
1
(a)
(b)
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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).4. 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.1. Rubber cover
2. Throttle cable free play adjusting bolt
3. Locknut
4. Throttle cable free play
4 2 1
3
(a)
(b)
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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.EBUM0190Front brake pads
Each brake pad is provided with a wear indicator
groove, which allows you to check the brake pad
wear without having to disassemble the brake. To
check the brake pad wear, check the wear indica-
tor groove. If a brake pad has worn to the point that
the wear indicator groove has almost disappeared,
have a Yamaha dealer replace the brake pads as
a set.
TIPThe wheels need to be removed to check thebrake pads. (See page 8-41.)EBU24190Rear 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-
place the brake pads as a set.1. Wear indicator groove
1
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EBU28930Checking 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
Rear brake1. Wear indicator
1
1. Minimum level mark
1. Minimum level mark
1
1
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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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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.
EBU24393Checking 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.
WARNING
EWB02471Operating with improperly serviced or adjust-
ed brakes could cause loss of braking ability,
which could lead to an accident.
After servicing:1. Brake lever free play
1
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Make sure the brakes operate smoothly and
that there is no free play.
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
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.
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
1
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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.
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.
1. Adjusting bolt
2. Cable length “A”
3. Locknut
2
1 3
1. Locknut
2. Adjusting nut
2
1
(a)(b)
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NOTICEECB00520When 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.TIPThe 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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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.
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 to its original position.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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