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83. Insert a new bulb into the socket, push it in,
and then turn it clockwise until it stops.
4. Install the lens by installing the screws.
NOTICEECB00700Do not overtighten the screws, otherwise thelens may break.EBU25651Removing a wheel 1. 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.
EBU25701Installing a wheel 1. Place the ATV on a level surface.
2. Install the wheel and the nuts.TIPThe arrow mark on the tire must point toward
the rotating direction of the wheel.Tapered nuts are used for both the front and rear
wheels. Install the nuts with their tapered side to-wards the wheel.
1. Wheel nut
1. Arrow mark
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8-56
8 3. Lower the ATV to the ground.
4. Tighten the wheel nuts to the specified
torques.
EBU25740Troubleshooting Although Yamaha ATVs receive a thorough in-
spection before shipment from the factory, trouble
may occur during operation. Any problem in the fu-
el, compression, or ignition systems, for example,
can cause poor starting and loss of power.
The following troubleshooting charts represent
quick and easy procedures for checking these vital
systems yourself. However, should your ATV re-
quire any repair, take it to a Yamaha dealer, whose
skilled technicians have the necessary tools, expe-
rience, and know-how to service the ATV properly.
Use only genuine Yamaha replacement parts. Im-
itation parts may look like Yamaha parts, but they
are often inferior, have a shorter service life and
can lead to expensive repair bills.
WARNING
EWB02280Do not smoke when checking the fuel system.
Fuel can ignite or explode, causing severe inju-
ry or property damage. Make sure there are no
open flames or sparks in the area, including pi-lot lights from water heaters or furnaces.
1. Tapered nutTightening torques:
Front wheel nut:
55 Nm (5.5 m·kgf, 40 ft·lbf)
Rear wheel nut:
55 Nm (5.5 m·kgf, 40 ft·lbf)
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9-1
9
EBU25860
CLEANING AND STORAGE
EBU25880Cleaning Frequent, 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 to
prevent 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 de-
greaser to the wheel axles.
3. Rinse the dirt and degreaser off with a garden
hose. Use only enough pressure to do the job.NOTICEECB00710Excessive water pressure may cause water
seepage and deterioration of wheel bearings,
brakes, transmission seals and electrical de-
vices. Many expensive repair bills have result-ed from improper high-pressure detergent
applications such as those available in coin-
operated car washers.
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 bot-
tle brush is handy for hard-to-reach places.
5. Rinse the ATV off immediately with clean wa-
ter and dry all surfaces with a chamois, clean
towel or soft absorbing cloth.
6. Clean the seat with a vinyl upholstery cleaner
to keep the cover pliable and glossy.
7. Automotive type wax may be applied to all
painted and chrome plated surfaces. Avoid
combination cleaner-waxes. Many contain
abrasives which may mar the paint or protec-
tive finish. When finished cleaning, start the
engine and let it idle for several minutes.
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9-3
9c. Install the spark plug cap onto the spark
plug, and then place the spark plug on the
cylinder head so that the electrodes are
grounded. (This will limit sparking during
the next step.)
d. Turn the engine over several times with the
starter. (This will coat the cylinder wall with
oil.)
e. Remove the spark plug cap from the spark
plug, and then install the spark plug and
the spark plug cap.
6. Lubricate all control cables and the pivoting
points of all levers and pedals.
7. Check and, if necessary, correct the tire air
pressure, and then block up the ATV so that
all of its wheels are off the ground. Alternative-
ly, turn the wheels a little every month in order
to prevent the tires from becoming degraded
in one spot.
8. Cover the muffler outlet with a plastic bag to
prevent moisture from entering it.
9. Remove the battery and fully charge it. Store
it in a cool, dry place and charge it once a
month. Do not store the battery in an exces-
sively cold or warm place [less than 0 °C (30°F) or more than 30 °C (90 °F)]. For more in-
formation on storing the battery, see page
8-47.
TIPMake any necessary repairs before storing theATV.
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10-1
10
EBU25960
SPECIFICATIONS
Dimensions:Overall length:
1978 mm (77.9 in)
Overall width:
1063 mm (41.9 in)
Overall height:
1095 mm (43.1 in)
Seat height:
840 mm (33.1 in)
Wheelbase:
1233 mm (48.5 in)
Ground clearance:
220 mm (8.7 in)
Minimum turning radius:
3000 mm (118 in)Weight:With oil and fuel:
250.0 kg (551 lb)Noise and vibration level:Noise level (77/311/EEC):
80.8 dB(A)
Vibration on seat (EN1032, ISO5008):
Will not exceed 0.7 m/s²
Vibration on handlebar (EN1032, ISO5008):
Will not exceed 2.5 m/s²Engine:Engine type:
Liquid cooled 4-stroke, SOHCCylinder arrangement:
Forward-inclined single cylinder
Displacement:
421.0 cm³
Bore × stroke:
84.5 × 75.0 mm (3.33 × 2.95 in)
Compression ratio:
10.00 :1
Starting system:
Electric starter
Lubrication system:
Wet sump
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10-3
10
Clutch:Clutch type:
Wet, centrifugal automaticTransmission:Primary reduction system:
V-belt
Secondary reduction system:
Shaft drive
Secondary reduction ratio:
39/24 × 24/18 × 33/9 (7.944)
Transmission type:
V-belt automatic
Operation:
Left hand operation
Forward gear:
38/23 (1.652)
Reverse gear:
29/17 (1.706)Chassis:Frame type:
Steel tube frame
Caster angle:
4.0 °
Trail:
19.3 mm (0.76 in)Front tire:Type:
Tubeless
Size:
AT23 x 8R12Manufacturer/model:
MAXXIS/M937
Rear tire:Type:
Tubeless
Size:
AT23 x 10R12
Manufacturer/model:
MAXXIS/M938Loading: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:
40.0 kPa (0.400 kgf/cm², 5.8 psi)
Rear:
40.0 kPa (0.400 kgf/cm², 5.8 psi)
Minimum:
Front:
37.0 kPa (0.370 kgf/cm², 5.3 psi)
Rear:
37.0 kPa (0.370 kgf/cm², 5.3 psi)Front wheel:Wheel type:
Panel wheel
Rim size:
12 x 6.0AT
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10-4
10
Rear wheel:Wheel type:
Panel wheel
Rim size:
12 x 7.5ATFront brake:Type:
Dual disc brake
Operation:
Right hand operation
Recommended fluid:
DOT 4Rear brake:Type:
Single disc brake
Operation:
Left hand and right foot operation
Recommended fluid:
DOT 4Front suspension:Type:
Double wishbone
Spring/shock absorber type:
Coil spring/oil damper
Wheel travel:
160 mm (6.3 in)Rear suspension:Type:
Swingarm
Spring/shock absorber type:
Coil spring/oil damperWheel travel:
180 mm (7.1 in)
Electrical system:Ignition system:
DC. CDI
Charging system:
AC magnetoBattery:Model:
YTX20L-BS
Voltage, capacity:
12 V, 18.0 AhHeadlight:Bulb type:
Krypton bulbBulb voltage, wattage × quantity:Headlight:
12 V, 30.0/30.0 W × 2
Tail/brake light:
12 V, 5.0/21.0 W × 1
Neutral indicator light:
LED
Reverse indicator light:
LED
Coolant temperature warning light:
LED
Park indicator light:
LED
On-Command four-wheel-drive indicator:
LCD
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10-5
10
Fuses:Main fuse:
30.0 A
Headlight fuse:
15.0 A
Signaling system fuse:
10.0 A
Ignition fuse:
10.0 A
Auxiliary DC jack fuse:
10.0 A
Backup fuse:
10.0 A
Four-wheel-drive motor fuse:
3.0 A
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