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8
WARNING
EWB02341Do not start the engine when cleaning the
spark arrester, otherwise it could cause injury
to the eyes, burns, carbon monoxide poison-
ing, possibly leading to death, and start a fire.
Always let the exhaust system cool prior to
touching exhaust components. EBU23921V-belt cooling duct check hoseIf dust or water collects in the V-belt cooling duct
check hose, remove the hose and clean it.
EBU23932V-belt case drain plugAfter riding in water deep enough to allow it to en-
ter the V-belt case, remove the V-belt case drain
plug to drain the water from the case.TIPIf water drains from the V-belt case after removing
the plug, have a Yamaha dealer check the ATV as
the water may affect other engine parts.
1. V-belt cooling duct check hose (left front side of ATV)
1
1. V-belt case drain plug
1
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EBU29703Adjusting the throttle lever free playThe throttle lever free play should be checked and,
if necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
The throttle lever free play should measure 3.0–5.0
mm (0.12–0.20 in) as shown. Periodically check
the throttle lever free play and, if necessary, adjust
it as follows.1. Slide the rubber cover back.
2. Loosen the locknut.
3. To increase the throttle lever free play, turn the throttle lever free play adjusting bolt in di-
rection (a). To decrease the throttle lever free
play, turn the adjusting bolt in direction (b).
4. Tighten the locknut.
5. Slide the rubber cover to its original position.
EBU24061Valve clearanceThe valve clearance changes with use, resulting in
improper air-fuel mixture and/or engine noise. To
prevent this from occurring, the valve clearance
must be adjusted by a Yamaha dealer at the inter-
vals specified in the periodic maintenance and lu-
brication chart.1. Throttle lever free play
2. Rubber cover
3. Locknut
4. Throttle lever free play adjusting bolt2
4 3
1
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8
2. Remove the seat. (See page 4-13.)
3. Remove the blown fuse, and then install a
new 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]
4. Turn on the main switch, start the engine, and then turn on the circuit in question.
5. If the fuse immediately blows again, have a Yamaha dealer check the vehicle.
Specified fuses:
Main fuse:40.0 A
Headlight fuse: 15.0 A
Ignition fuse: 10.0 A
Four-wheel-drive motor fuse: 3.0 A
Signaling system fuse: 10.0 A
Radiator fan motor fuse: 20.0 A
Auxiliary DC jack fuse: 10.0 A
Fuel injection system fuse: 10.0 A
EPS fuse: 40.0 A (YFM45KPAJ, YFM45KPHJ,
YFM45KPXJ)
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EBU27695Troubleshooting chartsStarting problems or poor engine performance
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.There is no fuel.
Check the battery.
Supply fuel.
The engine does not start.
Check the battery.
Operate the electric starter.4. Compression
There is compression.
There is no compression.
The engine does not start.
Have a Yamaha dealer check the ATV.
Remove the spark plug
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug. Have a Yamaha dealer check the ATV.
The engine does not start.
Check the compression.
DryWet
Operate the electric starter.
Have a Yamaha dealer check the ATV.
The engine does not start.
Check the ignition.
Operate the electric starter.2. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and have a Yamaha dealer charge
the battery if necessary.
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8-65
8Engine overheating
WARNING
EWB02291Wait for the engine and radiator to cool before removing the radiator cap. You could be burned by
hot fluid and steam blown out under pressure. Always put a thick rag over the cap when opening.
Allow any remaining pressure to escape before completely removing the cap. TIPIf coolant is not available, tap water can be temporarily used instead, provided that it is changed to the
recommended coolant as soon as possible. Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer check
and repair the cooling system.Add coolant. (See TIP.)
Start the engine. If the engine overheats again, have a
Yamaha dealer check and repair the cooling system.
There is
leakage.
There is
no leakage.
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EBU25861
CLEANING AND STORAGE
EBU25882CleaningFrequent, 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 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. 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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EBU27264StorageShort-term
Always store your ATV in a cool, dry place and, if
necessary, protect it against dust with a porous
cover. NOTICE: Storing the ATV in a poorly ven-
tilated room or covering it with a tarp while it is
still wet, will allow water and humidity to seep
in and cause rust. To prevent corrosion, avoid
damp cellars, stables (because of the presence
of ammonia) and areas where strong chemi-
cals are stored.
[ECB00722]
Long-term
Before storing your ATV for several months: 1. Make any necessary repairs and perform all outstanding maintenance.
2. Follow all the instructions in the Cleaning sec- tion of this chapter.
3. Fill up the fuel tank and add fuel stabilizer (Fu- el Med Rx if available), and then run the en-
gine for 5 minutes to distribute the treated
fuel. 4. Perform the following steps to protect the en-
gine from internal corrosion.a. Remove the spark plug cap and spark plug.
b. Pour a teaspoonful of engine oil into the spark plug bore.
c. 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.
5. Lubricate all control cables and the pivoting points of all levers and pedals.
6. Put the frame on stands or blocks to raise all wheels off the ground. (Alternatively, turn the
wheels each month to prevent the tires from
degrading in one spot.)
7. Cover the muffler outlet with a plastic bag to prevent moisture from entering it.
Specified amount:
7.5 ml per liter of fuel (1 oz per gallon)UBB560E0.book Page 2 Friday, March 10, 2017 10:20 AM
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EBU25962
SPECIFICATIONS
Dimensions:Overall length:2035 mm (80.1 in)
Overall width: 1180 mm (46.5 in)
Overall height:
1160 mm (45.7 in)
Seat height: 855 mm (33.7 in)
Wheelbase: 1240 mm (48.8 in)
Ground clearance:
245 mm (9.6 in)
Minimum turning radius: 3200 mm (126 in)Weight:Curb weight:
289.0 kg (637 lb) (YFM45KDHJ, YFM45KDXJ)
295.0 kg (650 lb) (YFM45KPAJ, YFM45KPHJ,
YFM45KPXJ)Noise and vibration level:Noise level (77/311/EEC):78.0 dB(A) (YFM45KPAJ, YFM45KPHJ,
YFM45KPXJ_EUR/FRA/GBR)
78.3 dB(A) (YFM45KDHJ, YFM45KDXJ_EUR/FRA/GBR) Uncertainty of measurement:
3.0 dB(A) (YFM45KDHJ, YFM45KDXJ_EUR/FRA/GBR,
YFM45KPAJ, YFM45KPHJ,
YFM45KPXJ_EUR/FRA/GBR)
Vibration on seat (EN1032, ISO5008): 0.6 m/s² (YFM45KDHJ, YFM45KDXJ_EUR/FRA/GBR)
Will not exceed 0.5 m/s² (YFM45KPAJ, YFM45KPHJ,
YFM45KPXJ_EUR/FRA/GBR)
Uncertainty of measurement: 0.0 m/s² (YFM45KPAJ, YFM45KPHJ,
YFM45KPXJ_EUR/FRA/GBR)
0.3 m/s² (YFM45KDHJ, YFM45KDXJ_EUR/FRA/GBR)
Vibration on handle (EN1032, ISO5008):
2.9 m/s² (YFM45KDHJ, YFM45KDXJ_EUR/FRA/GBR)
Will not exceed 2.5 m/s² (YFM45KPAJ, YFM45KPHJ,
YFM45KPXJ_EUR/FRA/GBR)
Uncertainty of measurement: 0.4 m/s² (YFM45KPAJ, YFM45KPHJ,
YFM45KPXJ_EUR/FRA/GBR)
0.5 m/s² (YFM45KDHJ, YFM45KDXJ_EUR/FRA/GBR)
Engine:Engine type:Liquid cooled 4-stroke, SOHC
Cylinder arrangement:
Single cylinder
Displacement: 421 cm³
Bore × stroke:
84.5 × 75.0 mm (3.33 × 2.95 in)
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