2018 YAMAHA YFZ450R brake

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
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 of the master cylinders and calipers as well as the
brake hoses replaced at the intervals listed below
or whenever they are damaged or leaking.

Oil seals: Replace every two years.
 Brake hoses: Replace every four years.
EBU24396Checking the front brake lever free
playThere should be no free play at the brake lever
end. If there is free play, have a Yamaha dealer in-
spect the brake system.1. No brake lever free play
1
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EBU24615Checking the brake pedal heightPeriodically check the brake pedal height. If the
brake pedal is not positioned as specified, have a
Yamaha dealer adjust it.
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.
1. Brake pedal heightBrake pedal height:11.7 mm (0.46 in)
1
1. Adjusting bolt
2. Cable length “A”
3. LocknutCable length “A”:47–51 mm (1.85–2.01 in)
1
2
3
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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. 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.
1. Locknut
2. Parking brake free play adjusting nut
3. Rubber cover
1
2
3
(b)
(a)
Tightening torque: Locknut (rear brake caliper):16 N·m (1.6 kgf·m, 12 lb·ft)
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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).
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.
1. Rear brake light switch
2. Rear brake light switch adjusting nut
1
2(a) (b)
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
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EBU24923Checking and lubricating the brake
and clutch leversThe operation of the brake and clutch levers
should be checked before each ride, and the lever
pivots should be lubricated if necessary.
Brake leverClutch lever
EBUM0171Checking the shift pedalThe operation of the shift pedal should be
checked before each ride. If operation is not
smooth, have a Yamaha dealer check the vehicle.EBU28872Checking and lubricating the brake
pedalThe operation of the brake pedal should be
checked before each ride, and the pedal pivot
should be lubricated if necessary.
Recommended lubricants:
Brake lever:Silicone grease
Clutch lever: Lithium-soap-based grease
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EBU26921Tail/brake lightThis model is equipped with an LED type of
tail/brake light.
If the tail/brake light does not come on, have a
Yamaha dealer check it.EBU25652Removing a wheel1. Place the ATV on a level surface.
2. Loosen the wheel nuts.
3. Elevate the ATV and place a suitable stand under the frame.
4. Remove the nuts from the wheel.
5. Remove the wheel.
EBU27484Installing a wheel1. Install the wheel with the arrow mark pointing in the forward rotating direction of the wheel,
and then install the wheel nuts.
2. Lower the ATV to the ground.
3. Tighten the wheel nuts to the specified torques.
1. Wheel nut
1. Arrow mark
2. Forward rotating direction
3. Wheel nut
2
3
3
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EBU25861
CLEANING AND STORAGE
EBU25903CleaningFrequent, thorough cleaning of your ATV will not
only enhance its appearance but will improve its
general performance and extend the useful life of
many components.1. Before cleaning the ATV: a. Block off the end of the exhaust pipe toprevent water entry. A plastic bag and
strong rubber band may be used.
b. Make sure the spark plug and all filler caps are properly installed.
2. If the engine case is excessively greasy, apply degreaser with a paint brush. Do not apply
degreaser to the chain, sprockets or wheel
axles.
3. Rinse the dirt and degreaser off with a garden hose. Use only enough pressure to do the
job. WARNING! Wet brakes may have re-
duced stopping ability, increasing the
chance of an accident. Test the brakes af-
ter washing. Apply the brakes several
times at slow speeds to let friction dry out
the linings.
[EWB02312]
NOTICE: Excessive wa- ter pressure may cause water seepage
and deterioration of wheel bearings,
brakes, transmission seals and electrical
devices. Many expensive repair bills have
resulted from improper high-pressure de-
tergent applications such as those avail-
able in coin-operated car washers.
[ECB00712]
4. Once most of the dirt has been hosed off,
wash all surfaces with warm water and mild,
detergent-type soap. An old toothbrush or
bottle brush is handy for hard-to-reach pla-
ces.
5. Rinse the ATV off immediately with clean wa- ter and dry all surfaces with a chamois, clean
towel or soft absorbing cloth.
6. Dry the chain and lubricate it to prevent it from rusting.
7. Clean the seat with a vinyl upholstery cleaner to keep the cover pliable and glossy.
8. Automotive type wax may be applied to all painted and chrome plated surfaces. Avoid
combination cleaner-waxes. Many contain
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Gear ratio:1st:
35/14 (2.500)
2nd: 30/15 (2.000)
3rd: 31/19 (1.632)
4th:
28/21 (1.333)
5th: 23/21 (1.095)Chassis:Frame type:
Aluminum die-cast and steel tube frame
Caster angle: 5.00 °
Trail: 21.0 mm (0.83 in)Front tire:Type:Tubeless
Size: AT21 x 7R10
Manufacturer/model:
MAXXIS/MS21Rear tire:Type:Tubeless
Size:
AT20 x 10R9
Manufacturer/model: MAXXIS/MS22
Loading:Maximum loading limit:100.0 kg (220 lb)
(Total weight of rider, cargo, accessories, and tongue)Tire air pressure (measured on cold tires):Recommended:
Front: 35.0 kPa (0.350 kgf/cm², 5.0 psi)
Rear:
35.0 kPa (0.350 kgf/cm², 5.0 psi)
Minimum: Front:
32.0 kPa (0.320 kgf/cm², 4.6 psi)
Rear: 32.0 kPa (0.320 kgf/cm², 4.6 psi)Front wheel:Wheel type:
Panel wheel
Rim size: 10 x 5.5ATRear wheel:Wheel type:
Panel wheel
Rim size: 9 x 8.0ATFront brake:Type:
Hydraulic disc brake
Operation: Right hand operation
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