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EBU28415Checking the front brake pads and rear
brake friction platesThe front brake pads and the rear brake friction
plates must be checked for wear at the intervals
specified in the periodic maintenance chart.TIPThis ATV is equipped with a wet, multiple-disc
type rear brake, which is located inside of the final
gear case. EBUM0191Front brake pads
Each brake pad is provided with a wear indicator
groove, which allows you to check the brake pad
wear without having to disassemble the brake. To
check the brake pad wear, check the wear indica-
tor groove. If a brake pad has worn to the point
that the wear indicator groove has almost disap-
peared, have a Yamaha dealer replace the brake
pads as a set.
TIPThe wheels need to be removed to check the
brake pads. (See page 9-64.) EBU30322Rear brake friction plates
The rear brake friction plates must be checked
and, if necessary, replaced by a Yamaha dealer at
the intervals specified in the periodic maintenance
chart.1. Wear indicator groove
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EBU29845Checking the brake fluid levelBefore riding, check that the brake fluid is above
the minimum level mark. Replenish the brake fluid
if necessary.TIPStraighten the handlebars for an accurate reading.
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 or brake sys-
tem leakage. Therefore, be sure to check the
brake pads for wear and the brake system for
leakage. If the brake fluid level suddenly goes
down, have a Yamaha dealer check the brake sys-
tem before further riding.
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.
1. Minimum level markSpecified brake fluid:
DOT 4
2WD
4WD
1
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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.
EBU24284Changing the brake fluidHave a Yamaha dealer change the brake fluid at
the intervals specified in the periodic maintenance
chart. In addition, 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 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.EBU34246Adjusting the rear brake lever and
brake pedal free playThe rear brake lever and brake pedal free play
must be checked and, if necessary, adjusted at
the intervals specified in the periodic maintenance
chart.1. No brake lever free play
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9Adjusting the brake lever free play
Measure the brake lever free play as shown.
If the free play is incorrect, adjust it as follows.
1. Loosen the locknut at the brake lever. 2. To increase the brake lever free play, turn the
brake lever free play adjusting bolt in direction
(a). To decrease the brake lever free play, turn
the adjusting bolt in direction (b).
TIPIf the specified brake lever free play could be ob-
tained as described above, skip steps 3–8. 3. Fully turn the adjusting bolt in direction (a) toloosen the brake cable.
4. Slide the rubber cover back.
1. Brake lever free playBrake lever free play: 6.0-7.0 mm (0.24-0.28 in)
1
1. Locknut
2. Brake lever free play adjusting bolt
(a)
(b)
12
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5. Loosen the brake cable adjuster locknut.
6. To increase the brake lever free play, turn the
brake lever free play adjusting nut in direction
(a). To decrease the brake lever free play, turn
the adjusting nut in direction (b).
7. Tighten the brake cable adjuster locknut.
8. Slide the rubber cover to its original position.
9. Tighten the locknut at the brake lever.
Adjusting the brake pedal free play
Measure the brake pedal free play as shown. If the free play is incorrect, adjust it as follows.
1. Remove panel G.
2. Loosen the locknut.
1. Brake cable adjuster locknut
2. Brake lever free play adjusting nut
3. Rubber cover
2
3
1
(a)(b)
1. Brake pedal free playBrake pedal free play: 12.0
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93. To increase the brake pedal free play, turn the
brake pedal free play adjusting nut in direc-
tion (a). To decrease the brake pedal free
play, turn the adjusting nut in direction (b).
4. Tighten the locknut.
5. Install the panel.
EBU24232Axle bootsThe axle boots must be checked for damage at
the intervals specified in the periodic maintenance
chart. Check the axle boots for tears or damage. If
any damage is found, have them replaced by a
Yamaha dealer.
1. Brake pedal free play adjusting nut
2. Locknut
2
(a)
(b)
1
1. Front axle boot (each sideF
1
1
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EBU34270Brake light switchesThe brake light, which is activated by the brake
pedal and brake levers, should come on just be-
fore braking takes effect.
The rear brake light switch can be adjusted as fol-
lows, but the front brake light switch should be ad-
justed 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).
EBU24905Checking and lubricating the cablesThe operation and the condition of all control ca-
bles should be checked before each ride, and the
cables and cable ends should be lubricated if nec-
essary. If a cable is damaged or does not move
smoothly, have a Yamaha dealer check or replace
it.
1. Rear axle boot (each side)
1
1
1. Rear brake light switch adjusting nut
2. Rear brake light switchRecommended lubricant:
Yamaha cable lubricant or other suitable cable lubricant
1
2 (b)
(a)
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WARNING
EWB02582Inspect cables frequently and replace if
damaged. Corrosion can result when the ca-
ble sheaths become damaged, and cables
can also become frayed or kinked, which
could restrict the operation of controls and
lead to an accident or injury.
Always make sure all control cables work
smoothly before you begin riding in cold
weather. If the control cables are frozen or
do not work smoothly, you could be unable
to control the ATV, which could lead to an
accident or collision. EBU28712Checking and lubricating the front and
rear brake leversThe operation of the front and rear brake levers
should be checked before each ride, and the lever
pivots should be lubricated if necessary. Front brake lever
Recommended lubricants:
Front brake lever:Silicone grease
Rear brake lever: Lithium-soap-based greaseUB5K64E0.book Page 49 Thursday, September 16, 2021 9:00 AM