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8
2. Remove the spark plug as shown, with the
spark plug wrench included in the owner’s tool
kit.
To check the spark plug 1. Check that the porcelain insulator around the center electrode of the spark plug is a medi-
um-to-light tan (the ideal color when the ATV
is ridden normally).
TIPIf the spark plug shows a distinctly different color,
the engine could be operating improperly. Do not
attempt to diagnose such problems yourself. In-
stead, have a Yamaha dealer check the ATV.2. Check the spark plug for electrode erosionand excessive carbon or other deposits, and
replace it if necessary.
3. Measure the spark plug gap with a wire thick- ness gauge and, if necessary, adjust the gap
to specification.
1. Spark plug wrench
Specified spark plug:NGK/LMAR6A-9
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8-43
8
13. Install the panel.
TIPThe air filter element should be cleaned every 20–
40 hours. It should be cleaned and lubricated more
often if the ATV is operated in extremely dusty ar-
eas. Each time the air filter element maintenance
is performed, check the air inlet of the air filter case
for obstructions. Check the air filter case rubber
joint to the throttle body and the rubber joint mani-
fold fittings for an air-tight seal. Tighten all fittings
securely to avoid the possibility of unfiltered air en-
tering the engine.EBU27813Cleaning the spark arrester Select a well-ventilated area free of combustible
materials and make sure the exhaust and muffler
are cool.
1. Remove the tailpipe bolts. 2. Remove the tailpipe by pulling it out of the
muffler, and then remove the gasket.
3. Tap the tailpipe lightly, and then use a wire brush to remove any carbon deposits from the
spark arrester portion of the tailpipe and inside
of the tailpipe housing.
1. Tailpipe bolt
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8
1. Remove panel G. (See page 8-10.)
2. Loosen the locknut.
3. Turn the brake pedal free play adjusting nut in
direction (a) to increase the free play, and in
direction (b) to decrease it. 4. Tighten the locknut.
5. After adjusting, there should be slight play at
the brake pedal cable joint as shown. If there
is no play, repeat steps 2 to 4.
1. Brake pedal free play
1. Locknut
2. Brake pedal free play adjusting nut
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8-52
86. Install the panel.
If the correct free play cannot be obtained, have a
Yamaha dealer adjust it.
TIPWhen adjusting the rear brake pedal free play:●Be sure not to step on the brake pedal.●Make sure the rear brake lever and brake pedal
do not move.
EBU24230Axle boots The axle boots must be checked for damage at the
intervals specified in the periodic maintenance and
lubrication chart. Check the axle boots for tears or
damage. If any damage is found, have them re-
placed by a Yamaha dealer.
1. Brake pedal cable joint
2. Slight play (0.1–0.5 mm [0.004–0.02 in])
1
2
1. Front axle boot (each side)
1
1
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8The main fuse, the fuel injection system fuse, the
EPS fuse, and the fuse box are located under pan-
el A. (See page 8-10.)
If a fuse is blown, replace it as follows.1. Turn the key to “ ” (off) and turn off all elec- trical circuits.
NOTICEECB00640To prevent accidental short-circuiting, turn off
the main switch when checking or replacing a
fuse.2. Remove the blown fuse, and then install anew fuse of the specified amperage.
WARNING! Always use a fuse of the spec-
ified rating, and never use a substitute ob-
ject in place of the proper fuse. An
improper fuse or a substitute object can
cause damage to the electrical system,
which could lead to a fire.
[EWB02172]
1. Auxiliary DC jack fuse
2. Four-wheel-drive motor fuse
3. Ignition fuse
4. Radiator fan fuse
5. Signaling system fuse
6. Headlight fuse
7. Spare fuseU1HS61E0.book Page 60 Wednesday, May 23, 2012 5:24 PM
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8
3. Turn the key to “ ” (on) and turn on the elec- trical circuits to check if the devices operate. 4. If the fuse immediately blows again, have a
Yamaha dealer check the electrical system.
EBU27443Replacing a headlight bulb If a headlight bulb burns out, replace it as follows.1. Remove the cover at the rear of the headlight by pulling it off.
2. Remove the headlight bulb cover.
Specified fuses:
Main fuse:40.0 A
Headlight fuse: 10.0 A
Ignition fuse: 10.0 A
Four-wheel-drive motor fuse: 10.0 A
Signaling system fuse: 5.0 A
Auxiliary DC jack fuse: 10.0 A
Radiator fan fuse: 20.0 A
Fuel injection system fuse: 15.0 A
EPS fuse: YFM550FAPD 40.0 A
YFM5FGPAD 40.0 A
YFM5FGPD 40.0 A
YFM5FGPHD 40.0 A
YFM5FGPLED 40.0 A1. Cover at the rear of the headlight
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83. Disconnect the headlight coupler. 4. Unhook the headlight bulb holder, and then
remove the burnt-out bulb.
5. Place a new headlight bulb into position, and then secure it with the bulb holder. NOTICE:
Do not touch the glass part of the head-
light bulb to keep it free from oil, otherwise
the transparency of the glass, the luminos-
ity of the bulb, and the bulb life will be ad-
versely affected. Thoroughly clean off any
dirt and fingerprints on the headlight bulb
using a cloth moistened with alcohol or
thinner.
[ECB00651]
1. Headlight bulb cover
1. Headlight coupler
1. Headlight bulb holder
2. Headlight bulb
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8
6. Connect the headlight coupler.
7. Install the headlight bulb cover.
NOTICE:
Make sure the headlight bulb cover is se-
curely fitted and seated properly.
[ECB01080]
8. Install the cover at the rear of the headlight.
9. 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).EBU25642Replacing the tail/brake light bulb If the tail/brake light bulb burns out, replace it as
follows. 1. Remove panel H. (See page 8-10.)
2. 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. Headlight beam adjusting screw
U1HS61E0.book Page 63 Wednesday, May 23, 2012 5:24 PM