YAMAHA YFM90 2017 Owners Manual

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8
do not work smoothly, you could be unable
to control the ATV, which could lead to an
accident or collision.
EBU28703Checking and lubricating the front and
rear brake leversThe operation of the front and rear brake levers
should be checked before each ride, and the lever
pivots should be lubricated if necessary.
Front brake lever
Rear brake lever
EBU24964Checking the wheel hub bearingsThe front and rear wheel hub bearings must be
checked at the intervals specified in the periodic
maintenance and lubrication chart. If there is play
in a wheel hub or if a wheel does not turn smooth-
ly, have a Yamaha dealer check the wheel hub
bearings.
Recommended lubricant:
Lithium-soap-based grease
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8
EBU28824Lubricating the front knuckle pivotsThe front knuckle pivots must be lubricated at the
intervals specified in the periodic maintenance
and lubrication chart.TIPFor parts equipped with a grease nipple, use a
grease gun.
EBU25094Lubricating the steering shaftThe steering shaft must be lubricated by a
Yamaha dealer at the intervals specified in the pe- riodic maintenance and lubrication chart.TIPFor parts equipped with a grease nipple, use a
grease gun.
Recommended lubricant: Lithium-soap-based grease
1. Grease nippleRecommended lubricant:Lithium-soap-based grease
1
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8
EBU34020BatteryThe battery is located under the seat. (See page
4-12.)
This model is equipped with a VRLA (Valve Regu-
lated Lead Acid) battery. There is no need to
check the electrolyte or to add distilled water.
However, the battery lead connections need to be
checked and, if necessary, tightened.
WARNING
EWB02161Battery electrolyte is poisonous and danger-
ous, as it contains sulfuric acid, which can cau-
se severe burns. Avoid contact with skin, eyes
or clothing. Always shield your eyes when
working near batteries.
Antidote:
EXTERNAL: Flush with water.
INTERNAL: Drink large quantities of water or
milk. Follow with milk of magnesia, beaten egg
or vegetable oil. Call a physician immediately.
EYES: Flush with water for 15 minutes and get
prompt medical attention.
Batteries produce explosive gases. Keep
sparks, flame, cigarettes or other sources of
ignition away. Ventilate when charging or using
in an enclosed space.KEEP OUT OF REACH OF CHILDREN.
NOTICEECB00621Never attempt to remove the battery cell seals,
as this would permanently damage the battery. To remove the battery
1. Remove the seat. (See page 4-12.)
2. Unhook the battery band.1. Positive battery lead (red)
2. Negative battery lead (black)
3. Battery
4. Battery band
3
4
2
1
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83. Disconnect the negative battery lead first,
then the positive battery lead by removing
their bolt. NOTICE: When removing the bat-
tery, the main switch must be off, and the
negative lead must be disconnected be-
fore the positive lead.
[ECB01002]
4. Pull the battery out of its compartment.
To charge the battery
Have a Yamaha dealer charge the battery as soon
as possible if it seems to have discharged. Keep
in mind that the battery tends to discharge more
quickly if the ATV is equipped with optional elec-
trical accessories.NOTICEECB00932To charge a VRLA (Valve Regulated Lead Acid)
battery, a special (constant-voltage) battery
charger is required. Using a conventional bat-
tery charger will damage the battery. To store the battery
 If the ATV will not be used for more than one
month, remove the battery, fully charge it, and
then place it in a cool, dry place. 
If the battery will be stored for more than two
months, check it at least once a month and fully
charge it if necessary.
NOTICEECB00941Always keep the battery charged. Storing a
discharged battery can cause permanent bat-
tery damage. To install the batteryTIPBe sure the battery is fully charged. 1. Place the battery in its compartment.
2. Connect the positive battery lead first, then
connect the negative battery lead by installing
their bolt. NOTICE: When installing the bat-
tery, the main switch must be off, and the
positive lead must be connected before
the negative lead.
[ECB01111]
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8
3. Hook the battery band.
4. Install the seat. (See page 4-12.)
EBU25244Replacing the fuseThe fuse holder is located under the seat. (See
page 4-12.)
If the fuse is blown, replace it as follows.
1. Turn the key to “OFF” and turn off all electrical circuits.NOTICEECB00641To prevent accidental short-circuiting, turn off
the main switch when checking or replacing a
fuse.
1. Positive battery lead (red)
2. Negative battery lead (black)
2
1
1. Fuse
2. Spare fuse
2 1
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82. 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]
3. Turn the key to “ON” and turn on the electricalcircuits to check if the devices operate.
4. If the fuse immediately blows again, have a Yamaha dealer check the electrical system.EBU34030Removing a wheel1. Place the ATV on a level surface.
2. Loosen the wheel bolts. 3. Elevate the ATV and place a suitable stand
under the frame.
4. Remove the bolts from the wheel.
5. Remove the wheel.
EBU34041Installing a wheel1. Install the wheel and the bolts.TIPWhen installing the wheel, make sure its arrow
mark points toward the rotating direction of
the wheel.
Specified fuse: 7.5 A
1. Wheel bolt
1
1
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8
2. Lower the ATV to the ground.
3. Tighten the wheel bolts to the specified
torques.
EBU25721TroubleshootingAlthough Yamaha ATVs receive a thorough in-
spection before shipment from the factory, trouble
may occur during operation. Any problem in the
fuel, compression, or ignition systems, for exam-
ple, 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, ex-
perience, and know-how to service the ATV prop-
erly.
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
EWB02281Do 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. Arrow markTightening torques:Front wheel bolt:45 Nm (4.5 m·kgf, 33 ft·lbf)
Rear wheel bolt: 45 Nm (4.5 m·kgf, 33 ft·lbf)
1
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EBU25754Troubleshooting chart
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.
The engine does not start.
Check the ignition.
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.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.
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.
DryWet
Open the throttle halfway and operate
the electric starter.
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EBU25861
CLEANING AND STORAGE
EBU25903CleaningFrequent, 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 chain, sprockets or 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. Dry the chain and lubricate it to prevent it from rusting.
7. Clean the seat with a vinyl upholstery cleaner to keep the cover pliable and glossy.
8. Automotive type wax may be applied to all painted and chrome plated surfaces. Avoid
combination cleaner-waxes. Many contain
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9abrasives which may mar the paint or protec-
tive finish. When finished cleaning, start the
engine and let it idle for several minutes.
EBU30361StorageShort-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. 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 depos-
its 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 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.
6. Lubricate all control cables and the pivoting points of all levers.
Specified amount:
7.5 ml of stabilizer to each liter of fuel (or 1
oz of stabilizer to each gallon of fuel)UBD361E0.book Page 2 Monday, January 25, 2016 10:53 AM