2010 YAMAHA GRIZZLY 250 Owners Manual

8-26
8 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 the
adjustment.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 3.0–
5.0 mm (0.12–0.20 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).
1. Throttle stop screwEngine idling speed:
1400–1500 r/min
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8
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.
EBU24071Adjusting the drive select lever safety
system cable The drive select lever safety system cable stretch-
es with use, which can result in improper function.
Therefore, the safety system cable should be
checked and adjusted by a Yamaha dealer at the
intervals specified in the periodic maintenance and
lubrication chart.EBU29601Brakes Replacement of brake components requires pro-
fessional knowledge. Brake service should be per-
formed by a Yamaha dealer.
WARNING
EWB02571Operating with improperly serviced or adjust-
ed brakes could lead to a loss in braking ability
and an accident.EBU24120Checking the front brake pads and rear
brake shoes The front brake pads and the rear brake shoes
must be checked for wear at the intervals specified
in the periodic maintenance and lubrication chart.
1. Rubber cover
2. Locknut
3. Throttle cable free play adjusting bolt
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8-28
8
EBU24171Front brake pads
Check each front brake pad for damage and mea-
sure the lining thickness. If a brake pad is dam-
aged or if the lining thickness is less than 1.0 mm
(0.04 in), have a Yamaha dealer replace the brake
pads as a set.TIPThe wheels need to be removed to check the
brake pads. (See page 8-45.)
EBU24180Rear brake shoes
The rear brake is provided with a wear indicator,
which allows you to check the brake shoe wear
without having to disassemble the brake. To check
the brake shoe wear, check the position of the
wear indicator while applying the brake. If a brake
shoe has worn to the point that the wear indicator
reaches the wear limit line or mark, have a
Yamaha dealer replace the brake shoes as a set.
1. Brake pad
2. Lining thickness
1. Wear indicator
2. Wear limit line
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8
EBU29840Checking 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.
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.EBU24281Changing 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,
1. Minimum level mark
Recommended brake fluid:
DOT 4
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8 have the oil seals of the brake master cylinder 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.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.
EBU24574Adjusting the brake pedal position,
free play and the rear brake lever free
play The brake pedal position and free play and the
brake lever free play must be checked and, if nec-
essary, adjusted at the intervals specified in the
periodic maintenance and lubrication chart.TIP
Always perform this maintenance completely in
the following order whenever adjusting the rear
brake.
Before adjusting the brake lever free play and
the brake pedal free play and position, check the
rear brake shoes for wear.1.Adjusting the brake pedal position
The top of the brake pedal should be posi-
tioned 43.0–53.0 mm (1.69–2.09 in) above
the top of the footboard bracket. If the position
is incorrect, adjust it as follows.
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8-31
8a. Remove the footboard. (See “Engine oil”
on page 8-11 for removal and installation
procedures.)
b. Loosen the locknuts at the brake pedal.
c. Turn the brake pedal position adjusting
bolt at the brake pedal in direction (a) to
raise the brake pedal, and in direction (b)
to lower it.
d. Tighten the locknuts at the brake pedal.
2.Adjusting the brake pedal free playThe brake pedal free play should measure
20.0–30.0 mm (0.79–1.18 in) as shown. If the
free play is incorrect, adjust it as follows.
a. Fully loosen the brake lever free play ad-
justing nut on the brake cable at the rear
wheel hub.
b. Turn the brake pedal free play adjusting
nut on the brake rod at the rear wheel hub
in direction (a) to increase the free play,
and in direction (b) to decrease it.
1. Locknut
2. Brake pedal position adjusting bolt
3. Brake pedal position
1. Brake pedal free play
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8 3.Adjusting the brake lever free play
The brake lever free play should measure
5.0–7.0 mm (0.20–0.28 in) as shown. If the
free play is incorrect, adjust it as follows.a. Loosen the locknut at the brake lever and
fully turn in the brake lever free play adjust-
ing bolt.
b. Turn the brake lever free play adjusting nut
on the brake cable at the rear wheel hub so
that the distance between the brake cam-
shaft lever and the pin, gap “A”, measures
0–1 mm (0–0.04 in).
1. Brake lever free play adjusting nut
2. Brake pedal free play adjusting nut
1. Brake lever free play
2. Locknut
3. Brake lever free play adjusting bolt
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8
c. Turn the brake lever free play adjusting
bolt at the brake lever in direction (a) to in-
crease the free play, and in direction (b) to
decrease it.d. Tighten the locknut at the brake lever.
e. Install the footboard.
TIPWhen adjusting the rear brake lever free play:
Be sure not to step on the brake pedal.
Make sure the brake pedal does not move.EBU24762Brake light switches The brake light, which is activated by the brake
pedal and brake levers, should come on just be-
fore braking takes effect.
1. Brake lever free play adjusting nut
2. Brake camshaft lever
3. Pin
4. Gap “A”
2 31 4
1. Locknut
2. Brake lever free play adjusting bolt
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