2012 YAMAHA YFZ450 lock

8-31
8
EBU24047Adjusting the throttle lever free play The throttle lever free play should be checked and,
if necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
The throttle lever free play should measure 2.0–
4.0 mm (0.08 –0.16 in) as shown. Periodically
check the throttle lever free play and, if necessary,
adjust it as follows.TIPThe engine idling speed must be checked, and ad-
justed if necessary, before adjusting the throttle le-
ver free play.1. Slide the rubber cover back.
2. Loosen the locknut.
3. To increase the throttle lever free play, turn the throttle lever free play adjusting bolt in di-
rection (a). To decrease the throttle lever 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 lever free play adjusting bolt
3. Locknut
4. Throttle lever free play
4
2
1
3
(a)
(b)
U1PD60E0.book Page 31 Monday, June 13, 2011 2:57 PM

8-35
8
5. Install the brake fluid reservoir bracket bolt.
6. Install the seat.
WARNING
EWB02720Improper maintenance can result in loss of
braking ability. Observe these precautions:

Insufficient brake fluid may allow air to enter
the brake system, reducing braking perfor-
mance.
Clean the filler cap before removing. Use
only DOT 4 brake fluid from a sealed contain-
er.
Use only the specified brake fluid; otherwise,
the rubber seals may deteriorate, causing
leakage.
Refill with the same type of brake fluid. Add-
ing a brake fluid other than DOT 4 may result
in a harmful chemical reaction.
Be careful that water does not enter the
brake fluid reservoir when refilling. Water
will significantly lower the boiling point of
the fluid and may result in vapor lock.NOTICEECB01160Brake fluid may damage painted surfaces or
plastic parts. Always clean up spilled fluid im-
mediately.As the brake pads wear, it is normal for the brake
fluid level to gradually go down. A low brake fluid
level may indicate worn brake pads and/or brake
system leakage; therefore, be sure to check the
1. Frame
2. Projection
3. Brake fluid reservoir bracket
4. BoltSpecified brake fluid:
DOT 4
2 3
1 4
U1PD60E0.book Page 35 Monday, June 13, 2011 2:57 PM

8-37
8
EBU24715Adjusting 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 47 –51 mm
(1.85 –2.01 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. Slide the rubber cover back at the brake ca- ble.
4. Loosen the locknut.
5. Turn the parking brake free play adjusting nut in direction (a) to increase the cable length,
and in direction (b) to decrease it.1. Brake pedal height
1
1. Adjusting bolt
2. Cable length “A”
3. Locknut
2
3 1
U1PD60E0.book Page 37 Monday, June 13, 2011 2:57 PM

8-38
8
TIPIf the cable length cannot be adjusted to specifica-
tion, consult a Yamaha dealer.6. Tighten the locknut on the brake cable.
7. Slide the rubber cover to its original position.
8. 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.EBU24743Brake light switches The brake light, which is activated by the brake
pedal and brake lever, should come on just before
braking takes effect.
1. Locknut
2. Parking brake free play adjusting nut
3. Rubber cover
(a)
(b)
1
2
3
Tightening torque: Locknut (rear brake caliper):16 Nm (1.6 m ·kgf, 12 ft· lbf)
U1PD60E0.book Page 38 Monday, June 13, 2011 2:57 PM

8-39
8
The brake light switch for the brake pedal can be
adjusted as follows, but the front brake light switch
should be adjusted by a Yamaha dealer.
Turn the rear brake light switch 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 adjusting nut in direction (b).
EBU30600Adjusting 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 8.0
–
13.0 mm (0.31 –0.51 in) as shown. If the free play
is incorrect, adjust it as follows. 1. Slide the rubber cover back at the clutch lever.
2. Loosen the locknut.
3. To increase the clutch lever free play, turn the adjusting bolt at the clutch lever in direction
(a), and to decrease it, turn the bolt in direction
(b).1. Rear brake light switch
2. Rear brake light switch adjusting nut
(a) (b)1
2
1. Clutch lever free play
2. Locknut
3. Clutch lever free play adjusting bolt
4. Rubber cover1 3
4
(a)
(b)
2
U1PD60E0.book Page 39 Monday, June 13, 2011 2:57 PM

8-40
8
TIPIf the specified clutch lever free play could be ob-
tained as described above, skip steps 4–8.4. Fully turn the adjusting bolt at the clutch lever
in direction (a) to loosen the clutch cable.
5. Slide the rubber cover back at the clutch ca- ble.
6. Loosen the locknut.
7. To increase the clutch lever free play, turn the adjusting nut at the clutch cable in direction
(a), and to decrease it, turn the nut in direction
(b).
8. Tighten the locknut at the clutch cable, andthen slide the rubber cover to its original posi-
tion.
9. Tighten the locknut at the clutch lever, and then slide the rubber cover to its original posi-
tion.
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.1. Locknut
2. Clutch lever free play adjusting nut
3. Rubber cover
(a)
(b)
1
2
3
U1PD60E0.book Page 40 Monday, June 13, 2011 2:57 PM

8-52
84. Remove the headlight bulb holder by pushing
it in and turning it counterclockwise, and then
remove the burnt-out bulb. 5. Place a new headlight bulb into position.
NOTICE: Do not touch the glass part of the
headlight bulb to keep it free from oil, oth-
erwise the transparency of the glass, the
luminosity of the bulb, and the bulb life will
be adversely affected. Thoroughly clean
off any dirt and fingerprints on the head-
light bulb using a cloth moistened with al-
cohol or thinner.
[ECB00651]
1. Headlight bulb holder cover
2. Headlight coupler
1
2
1. Headlight bulb holder
1
U1PD60E0.book Page 52 Monday, June 13, 2011 2:57 PM

8-53
8
6. Install the headlight bulb holder by pushing it
in and turning it clockwise.
7. Install the headlight bulb holder cover.
8. Connect the headlight coupler.
9. Install the headlight unit by installing the bolts.
10. Adjust the headlight beam if necessary.
EBU25551Adjusting a headlight beam NOTICEECB00690It is advisable to have a Yamaha dealer make
this adjustment.
To raise a headlight beam, turn the headlight beam
adjusting screw in direction (a).
To lower a headlight beam, turn the adjusting
screw in direction (b).EBU25613Replacing the tail/brake light bulb If the tail/brake light bulb burns out, replace it as
follows. 1. Remove the tail/brake light bulb holder (to- gether with the bulb) by turning it counter-
clockwise.
1. Do not touch the glass part of the bulb.
1
1. Headlight beam adjusting screw
1 (a)
(b)
U1PD60E0.book Page 53 Monday, June 13, 2011 2:57 PM