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8
EBU23214Checking the spark plugThe spark plug is an important engine component,
which is easy to check. Since heat and deposits
will cause any spark plug to slowly erode, the
spark plug should be removed and checked in ac-
cordance with the periodic maintenance and lubri-
cation chart. In addition, the condition of the spark
plug can reveal the condition of the engine.
To remove the spark plug1. Remove the spark plug cap. 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).1. Spark plug cap1
1. Spark plug wrench
1
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82. 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. 4. Check the gasket for damage, and replace it
if necessary.
5. Make sure the gasket is properly positioned, then insert the tailpipe into the muffler and
align the bolt holes.
6. Install the bolts and tighten them to the spec- ified torque.
1. Tailpipe bolt
1
1
1. Gasket
2. Spark arrester
3. TailpipeTightening torque:
Tailpipe bolt:10 Nm (1.0 m·kgf, 7.2 ft·lbf)
3
2
1
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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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86. Install the panel.
If the correct free play cannot be obtained, have a
Yamaha dealer adjust it.
TIPWhen adjusting the 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. 
EBU24231Axle bootsThe 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 replaced 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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EBU30521Replacing a fuse
The 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.
1. Fuse box
2. Main fuse
3. EPS fuse
4. Fuel injection system spare fuse
5. Fuel injection system fuse
1. Auxiliary DC jack fuse
2. Four-wheel-drive motor fuse
3. Ignition fuse
4. Radiator fan motor fuse
5. Signaling system fuse
6. Headlight fuse
7. Spare fuse
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NOTICEECB00641To 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.
 [EWB02173]
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.
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 motor fuse: 20.0 A
Fuel injection system fuse: 15.0 A
EPS fuse: 40.0 A
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EBU27444Replacing a headlight bulbIf 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. 3. Disconnect the headlight coupler.1. Cover at the rear of the headlight
1. Headlight bulb cover
1. Headlight coupler
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8
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.
 [ECB00652]
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.
 [ECB01081]
8. Install the cover at the rear of the headlight.
9. Adjust the headlight beam if necessary.EBU25552Adjusting a headlight beamNOTICEECB00691It is advisable to have a Yamaha dealer make
this adjustment. 
1. Headlight bulb holder
2. Headlight bulb
1. Do not touch the glass part of the bulb.
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