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The service information included in this manual
and the tools provided in the owner’s tool kit are in-
tended to assist you in the performance of preven-
tive maintenance and minor repairs. However,
additional tools such as a torque wrench may be
necessary to perform certain maintenance work
correctly.
TIP
If you do not have the tools or experience required
for a particular job, have a Yamaha dealer perform
it for you.
WARNING
EWB01850
Never modify this ATV through improper in-
stallation or use of accessories, as it may
cause changes in handling, which in some sit-
uations could lead to an accident. All parts and
accessories added to this ATV should be gen-
uine Yamaha or equivalent components de-
signed for use on this ATV and should be
installed and used according to instructions. If
you have questions, consult an authorized
Yamaha ATV dealer.
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2. Check the spark plug for electrode erosion
and excessive carbon or other deposits, and
replace it if necessary.
To install the spark plug
1. Measure the spark plug gap with a wire thick-
ness gauge and, if necessary, adjust the gap
to specification.2. Clean the surface of the spark plug gasket
and its mating surface, and then wipe off any
grime from the spark plug threads.
3. Install the spark plug with the spark plug
wrench, and then tighten it to the specified
torque.
TIP
If a torque wrench is not available when installing
a spark plug, a good estimate of the correct torque
is 1/4–1/2 turn past finger tight. However, the spark
plug should be tightened to the specified torque as
soon as possible.
4. Install the spark plug cap.
EBU23265
Engine oil
The engine oil level should be checked before
each ride. In addition, the oil must be changed at
the intervals specified in the periodic maintenance
and lubrication chart. Specified spark plug:
NGK/CR7HSA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
1. Spark plug gap
Tightening torque:
Spark plug:
12.5 Nm (1.3 m·kgf, 9.0 ft·lbf)
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To change the engine oil
1. Place the ATV on a level surface.
2. Start the engine, warm it up for several min-
utes, and then turn it off.
3. Place an oil pan under the engine to collect
the used oil.
4. Remove the engine oil filler cap, and then re-
move the engine oil drain bolt to drain the oil
from the crankcase.
NOTICE
ECB00310
When removing the engine oil drain bolt, the
compression spring, oil strainer and O-ring will
fall out. Take care not to lose these parts.
5. Clean the oil strainer with solvent.
6. Check the O-ring for damage and replace it if
necessary.
7. Install the O-ring, oil strainer, compression
spring and drain bolt. Tighten the engine oil
drain bolt to the specified torque.NOTICE
ECB00320
Before installing the engine oil drain bolt, be
sure to install the O-ring, compression spring
and oil strainer.
8. Refill with the specified amount of the recom-
mended engine oil, and then install and tight-
en the engine oil filler cap.
1. Engine oil drain bolt
2. O-ring
3. Spring
4. Oil strainer
1
4
3
21
Tightening torque:
Engine oil drain bolt:
32 Nm (3.2 m·kgf, 23.1 ft·lbf)
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To change the transmission oil
1. Place the ATV on a level surface.
2. Start the engine, warm it up for several min-
utes, and then turn it off.
3. Place an oil pan under the transmission to col-
lect the used oil.
4. Remove the oil filler bolt and the drain bolt to
drain the oil from the transmission case.5. Install the drain bolt, and then tighten it to the
specified torque.
6. Refill with the specified amount of the recom-
mended transmission oil, and then install and
tighten the oil filler bolt.
NOTICE
ECB00790
Make sure that no foreign material enters the
transmission case.
Make sure that no oil gets on the tires or
wheels.
7. Start the engine, and then let it idle for several Tightening torque:
Screw:
16 Nm (1.6 m·kgf, 11.6 ft·lbf)
Oil filler bolt:
23 Nm (2.3 m·kgf, 16.6 ft·lbf)
1. Transmission oil drain bolt
1
Tightening torque:
Transmission oil drain bolt:
23 Nm (2.3 m·kgf, 16.6 ft·lbf)
Recommended transmission oil:
See page 10-1.
Oil quantity:
0.6 L (0.63 US qt, 0.53 Imp.qt)
Tightening torque:
Oil filler bolt:
23 Nm (2.3 m·kgf, 16.6 ft·lbf)
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4. Loosen the chain adjusting bolt locknut. To
tighten the drive chain, turn the adjusting bolt
in direction (a). To loosen the drive chain, turn
the adjusting bolt in direction (b), and then
push the wheels forward.
NOTICE
ECB00541
Improper drive chain slack will overload the en-
gine as well as other vital parts of the ATV and
can lead to drive chain slippage or breakage.
To prevent this from occurring, keep the drive
chain slack within the specified limits.
5. Tighten the locknut and the axle holding bolts
to the specified torques.
1. Hub stopper bolt
2. Locknut
3. Axle holding bolt (lower)
4. Axle holding bolt (upper)
1
2
34
1. Locknut
2. Drive chain slack adjusting bolt
1
2
(a)
(b)
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NOTICE
ECB00550
If measurement “A” of the drive chain adjust-
ing bolt is less than 27 mm (1.06 in), have a
Yamaha dealer replace the drive chain.
6. Tighten the hub stopper bolt, and then its lock-
nut.
EBU24880
Lubricating the drive chain
The drive chain must be cleaned and lubricated at
the intervals specified in the periodic maintenance
and lubrication chart, otherwise it will quickly wear
out, especially when riding in dusty or wet areas.
Service the drive chain as follows. Tightening torques:
Chain adjusting bolt locknut:
15.5 Nm (1.6 m·kgf, 11.2 ft·lbf)
Axle holding bolt (upper):
85 Nm (8.5 m·kgf, 61.5 ft·lbf)
Axle holding bolt (lower):
60 Nm (6.0 m·kgf, 43.4 ft·lbf)
1. Measurement A
1
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Front
3. Elevate the ATV and place a suitable stand
under the frame.
4. Remove the nuts from the wheel.
5. Remove the wheel.
EBU25692
Installing a wheel
1. Place the ATV on a level surface.
2. Elevate the ATV and place a suitable stand
under the frame.
3. Install the wheel and the nuts.TIP
Tapered nuts are used for both the front and rear
wheels. Install the nuts with their tapered side to-
wards the wheel.
4. Lower the ATV to the ground.
5. Tighten the wheel nuts to the specified
torques.
1. Wheel nut
1
1
1. Tapered nut
1
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EBU25720
Troubleshooting
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 chart represents a
quick and easy procedure 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
EWB02280
Do 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.
Tightening torques:
Front wheel nut:
55 Nm (5.5 m·kgf, 39.8 ft·lbf)
Rear wheel nut:
55 Nm (5.5 m·kgf, 39.8 ft·lbf)