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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.
1. Owner’s manual
2. Low-pressure tire gauge
3. Owner’s tool kit
1
2 3
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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.
EBU23266
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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![YAMAHA GRIZZLY 125 2010 Owners Manual
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may result.
[ECB00851]
6. Insert the dipstick into the oil filler hole, and
then tighten the engine oil filler cap.
To change the engine oil
1. Place the ATV on YAMAHA GRIZZLY 125 2010 Owners Manual
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may result.
[ECB00851]
6. Insert the dipstick into the oil filler hole, and
then tighten the engine oil filler cap.
To change the engine oil
1. Place the ATV on](/manual-img/51/50333/w960_50333-79.png)
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may result.
[ECB00851]
6. Insert the dipstick into the oil filler hole, and
then tighten the engine oil filler cap.
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:
When remov-
ing the engine oil drain bolt, the compres-
sion spring, oil strainer and O-ring will fall
out. Take care not to lose these
parts.
[ECB00311]
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:
Before installing the engine oil drain bolt,
be sure to install the O-ring, compression
spring and oil strainer.
[ECB00321]
1. Engine oil drain bolt
2. O-ring
3. Spring
4. Oil strainer
1
4
3
21
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8. Refill with the specified amount of the recom-
mended engine oil, and then install and tight-
en the engine oil filler cap.
TIP
Be sure to wipe off spilled oil on any parts after the
engine and exhaust system have cooled down.
NOTICE
ECB00330
Do not use oils with a diesel specification of
“CD” or oils of a higher quality than speci-
fied. In addition, do not use oils labeled “EN-
ERGY CONSERVING II” or higher.
Make sure that no foreign material enters the
crankcase.
9. Start the engine, and then let it idle for several
minutes while checking it for oil leakage. If oil
is leaking, immediately turn the engine off and
check for the cause.
10. Turn the engine off, wait at least ten minutes,
and then check the oil level and correct it if
necessary.
EBU27025
Transmission oil
The transmission oil level should be checked be-
fore each ride. In addition, the transmission oil
must be changed at the intervals specified in the
periodic maintenance and lubrication chart.
To check the transmission oil level
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. Wait a few minutes until the oil settles, and
then loosen the transmission oil check screw
located at the right side of the crankcase until
oil flows out. Tightening torque:
Engine oil drain bolt:
32 Nm (3.2 m·kgf, 23.1 ft·lbf)
Recommended oil:
See page 10-1.
Oil quantity:
1.25 L (1.32 US qt, 1.10 Imp.qt)
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4. If no oil flows out, remove the oil filler bolt.5. Pour the recommended type of oil in the trans-
mission oil filler hole until it flows out of the
check screw hole.
6. Install the transmission oil check screw and
transmission oil filler bolt, and then tighten
them to the specified torques.
1. Transmission oil check screw
2. Transmission oil level check hole
3. Correct oil level
1 32
1. Transmission oil filler bolt
Tightening torque:
Transmission oil check screw:
16 Nm (1.6 m·kgf, 11.6 ft·lbf)
Transmission oil filler bolt:
23 Nm (2.3 m·kgf, 16.6 ft·lbf)
1
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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 transmission oil filler bolt and the
transmission oil 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:
Make sure
that no foreign material enters the trans-
mission case.
[ECB00791]
NOTICE
ECB01061
Make sure that no oil gets on the tires or
wheels.
7. Start the engine, and then let it idle for several
minutes while checking the transmission for
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:
Transmission oil filler bolt:
23 Nm (2.3 m·kgf, 16.6 ft·lbf)
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age. To prevent this from occurring, keep
the drive chain slack within the specified
limits.
[ECB00542]
5. Tighten the locknut and the axle holding bolts
to the specified torques.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.
1. Locknut
2. Drive chain slack adjusting bolt
1
2
(a)
(b)
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)
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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.
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.
1. Tapered nut
1
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)