2008 YAMAHA YFM250R Owners Manual

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EBU24000
Adjusting 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.
NOTE:

A diagnostic tachometer is needed to make this
adjustment.
1. Start the engine and warm it up.
NOTE:

The 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).
NOTE:

If the specified idling speed cannot be obtained as
described above, have a Yamaha dealer make the
adjustment.
EBU24043
Adjusting 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
1. Throttle stop screw
Engine idling speed:
1500–1600 r/min
1
(a)
(b)

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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.
NOTE:

The engine idling speed must be checked, and ad-
justed if necessary, before adjusting the throttle ca-
ble free play.
1. Loosen the locknut.
2. To increase the throttle cable free play, turn
the adjusting bolt in direction (a). To decrease
the throttle cable free play, turn the adjusting
bolt in direction (b).
3. Tighten the locknut.
EBU24060
Valve 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. Locknut
2. Throttle cable free play adjusting bolt
3. Throttle lever free play
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(a)(b)

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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
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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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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
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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
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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
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1. Adjusting bolt
2. Cable length “A”
3. Locknut
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