2019 YAMAHA YFZ450 lock

8-10
8
EBU30131Removing and installing the cowling
and panelsThe cowling and panels shown need to be re-
moved to perform some of the maintenance jobs
described in this chapter. Refer to this section
each time a cowling or panel needs to be removed
and installed.
EBU29596Panel A
To remove the panel1. Remove the seat. (See page 4-10.)
2. Remove the fuel tank cap by turning it coun-terclockwise. (See page 4-8.) NOTICE: Make
sure that no foreign material enters the
fuel tank.
[ECB01052]
3. Loosen the quick fasteners.
1. Panel A
2. Panel B
3. Cowling
1
2
3
1. Panel C
1
UBW262E0.book Page 10 Tuesday, April 3, 2018 10:59 AM

8-11
84. Remove the quick fasteners, and then slide
the panel backward and pull upward. 5. Install the fuel tank cap by turning it clock-
wise.
To install the panel
1. Remove the fuel tank cap by turning it coun- terclockwise.
2. Place the panel in the original position, and then install the quick fasteners. NOTICE:
When installing the panel, be sure not to
pinch the cables or wires.
[ECB00382]
3. Tighten the quick fasteners.
4. Install the fuel tank cap by turning it clock- wise.
5. Install the seat.
1. Quick fastener
1. Quick fastener
1 1
1
UBW262E0.book Page 11 Tuesday, April 3, 2018 10:59 AM

8-28
8
EBU29704Adjusting the throttle lever free playPeriodically check the throttle lever free play and
adjust if necessary.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.
EBU24061Valve clearanceThe 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.EBU29602BrakesReplacement of brake components requires pro-
fessional knowledge. Brake service should be
performed by a Yamaha dealer.
WARNING
EWB02572Operating with improperly serviced or adjust-
ed brakes could lead to a loss in braking ability
and an accident.
1. Rubber cover
2. Throttle lever free play adjusting bolt
3. Locknut
4. Throttle lever free playThrottle lever free play: 2.0–4.0 mm (0.08–0.16 in)
32
4
(a)(b)
1
UBW262E0.book Page 28 Tuesday, April 3, 2018 10:59 AM

8-31
8
TIPTo check the rear brake fluid level, remove the
seat. (See page 4-10.)
WARNING
EWB02721Improper 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 flu-
id and may result in vapor lock.
NOTICEECB01161Brake 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
brake pads for wear and the brake system for
leakage. If the brake fluid level goes down sud-
denly, have a Yamaha dealer check the cause be-
fore further riding.EBU24293Changing the brake fluidHave a Yamaha dealer change the brake fluid at
the intervals specified in the periodic maintenance
and lubrication chart. In addition, have the oil seals
Specified brake fluid:
DOT 4
UBW262E0.book Page 31 Tuesday, April 3, 2018 10:59 AM

8-33
8
EBU24717Adjusting the parking brake free playPeriodically check the cable length “A” and adjust
if necessary.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.
TIPIf the cable length cannot be adjusted to specifi-
cation, consult a Yamaha dealer. 6. Tighten the locknut on the brake cable.
7. Slide the rubber cover to its original position.
1. Adjusting bolt
2. Cable length “A”
3. LocknutCable length “A”:47–51 mm (1.85–2.01 in)
1
2
3
1. Locknut
2. Parking brake free play adjusting nut
3. Rubber cover
1
2
3
(b)
(a)
UBW262E0.book Page 33 Tuesday, April 3, 2018 10:59 AM

8-34
8
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.
[ECB00522]
WARNING
EWB02091Operating 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.
EBU24744Brake light switchesThe brake light, which is activated by the brake
pedal and brake lever, should come on just before
braking takes effect.
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).
Tightening torque:
Locknut (rear brake caliper):16 N·m (1.6 kgf·m, 12 lb·ft)1. Rear brake light switch
2. Rear brake light switch adjusting nut
1
2(a) (b)
UBW262E0.book Page 34 Tuesday, April 3, 2018 10:59 AM

8-35
8
EBU30155Adjusting the clutch lever free playPeriodically check the clutch lever free play and
adjust if necessary.1. To increase the clutch lever free play, turn the clutch lever free play adjusting nut at the
clutch lever in direction (a), and to decrease it,
turn the nut in direction (b).
If the specified free play cannot be obtained,
proceed with the following steps. 2. Fully turn the adjusting nut at the clutch lever
in direction (a) to loosen the clutch cable.
3. Slide back the rubber cover at the clutch ca- ble.
4. Loosen the locknut.
5. To increase the clutch lever free play, turn the clutch lever free play adjusting nut located to-
wards the center of the cable in direction (a),
and to decrease it, turn the nut in direction (b).
6. Tighten the locknut.
7. Slide the rubber cover to its original position.1. Clutch lever free play
2. Clutch lever free play adjusting nut (clutch lever)Clutch lever free play: 8.0–13.0 mm (0.31–0.51 in)
1
(a)
(b)
2
1. Locknut
2. Clutch lever free play adjusting nut (clutch cable)
3. Rubber cover
1
2
3
(b)
(a)
UBW262E0.book Page 35 Tuesday, April 3, 2018 10:59 AM

8-47
82. Remove the bulb cover. 3. Remove the socket by pushing it in and turn-
ing it counterclockwise, and then remove the
burnt-out bulb.
4. Place a new headlight bulb into position. NOTICE: Do not touch the glass part of the
bulb. Oil from your fingers or other con-
tamination will adversely affect the trans-
parency of the glass, luminosity of the
bulb, and bulb life. Thoroughly clean off
any dirt and fingerprints using a cloth
moistened with alcohol or thinner.
[ECB00653]
1. Headlight unit
2. Bolt
1. Bulb cover
1
2
1
1. Socket
1
UBW262E0.book Page 47 Tuesday, April 3, 2018 10:59 AM