2009 YAMAHA YFM90R Owners Manual

8-32
2. Elevate the ATV and place a suitable standunder the frame.
3. Remove the nuts from the wheel.
4. Remove the wheel.
1. Wheel nutsRemoving a wheel 1. Loosen the wheel nuts.
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1
1

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2. Lower the ATV to the ground.
3. Tighten the wheel nuts to the specifiedtorques.
Tightening torques: Front wheel nut:45 Nm (4.5 m·kgf, 33 ft·lbf)
Rear wheel nut: 45 Nm (4.5 m·kgf, 33 ft·lbf)
wheel.
Front
1. Arrow markInstalling a wheel 1. Install the wheel and the nuts.TIPWhen installing the wheel, make sure its arrow
mark points toward the rotating direction of the
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1

8-34
TroubleshootingAlthough 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.
8
WARNING
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.

8-35
Troubleshooting chart
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.There is no fuel.
Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter.2. Compression
There is compression.
There is no compression.
Check the ignition. 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.
Have a Yamaha dealer
check the ATV.
The engine does not start.
Check the battery.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections, and
charge the battery if necessary.
DryWet
Open the throttle halfway and operate
the electric starter.
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9-1

CLEANING AND STORAGE
CleaningFrequent, 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 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.N O T I C EExcessive 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.
9

9-2
StorageShort-term
Always store your ATV in a cool, dry place and, if
necessary, protect it against dust with a porous
cover.N O T I C EStoring the ATV in a poorly ventilated 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 ammo-nia) and areas where strong chemicals arestored. Long-term
Before storing your ATV for several months:
1. Follow all the instructions in the “Cleaning” section of this chapter.
2. Turn the fuel cock lever to “OFF”.
3. Drain the carburetor float chamber by loosen- ing the drain bolt; this will prevent fuel deposits
from building up. Pour the drained fuel into the
fuel tank.
4. Fill up the fuel tank and add fuel stabilizer (if available) to prevent the fuel from deteriorat-
ing.
5. Perform the following steps to protect the cyl- inder, piston rings, etc. from corrosion.
a. Remove the spark plug cap and sparkplug.
b. Pour a teaspoonful of engine oil into the spark plug bore.
c. Install the spark plug cap onto the spark
Specified amount:
7.5 ml of stabilizer to each liter of fuel (or 1 oz
of stabilizer to each gallon of fuel)
9
WARNING
Wet brakes may have reduced stopping ability,
increasing the chance of an accident. Test the
brakes after washing. Apply the brakes several
times at slow speeds to let friction dry out thelinings.

9-3
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 infor-
mation on storing the battery, see page 8-26.
TIPMake any necessary repairs before storing theATV.
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10-1
10
SPECIFICATIONS
Engine:Engine type: Forced air cooled 4-stroke
Cylinder arrangement: Single cylinder
Displacement: 88 cm (5.37 cu.in)
3
Bore × stroke: 47.0 × 51.0 mm (1.85 x 2.0 in) Compression ratio:
Starting system: Electric starter & kickstarter
Lubrication system: Wet sump 10.2 : 1
Engine oil:Type:SAE10W-40 or SAE20W-50
Recommended engine oil grade: API service SG type or higher, JASO standard MA0 10 30
507090
110130 F
SAE 10W-40
SAE 5W-30
-20
-10 0 102030 40 50 C
SAE 20W-50
Dimensions:Overall length:
1490 mm (58.7 in)
Overall width: 885 mm (34.8 in)
Overall height: 910 mm (35.8 in)
Seat height: 654 mm (25.7 in)
Wheelbase: 1010 mm (39.8 in)
Ground clearance: 100 mm (3.9 in)
Minimum turning radius: 2900 mm (114 in)Weight:With oil and fuel: 120.0 kg (264 lb)