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9
EBU28415Checking the front brake pads and rear
brake friction platesThe front brake pads and the rear brake friction
plates must be checked for wear at the intervals
specified in the periodic maintenance chart.TIPThis ATV is equipped with a wet, multiple-disc
type rear brake, which is located inside of the final
gear case. EBU24174Front brake padsCheck each front brake pad for damage and mea-
sure the lining thickness. If a brake pad is dam-
aged or if the lining thickness reaches the
specified limit, have a Yamaha dealer replace the
brake pads as a set.
TIPThe wheels need to be removed to check the
brake pads. (See page 9-63.) EBU30322Rear brake friction plates
The rear brake friction plates must be checked
and, if necessary, replaced by a Yamaha dealer at
the intervals specified in the periodic maintenance
chart.EBU29845Checking the brake fluid levelBefore riding, check that the brake fluid is above
the minimum level mark. Replenish the brake fluid
if necessary.
1. Lining thickness
Brake pad lining thickness limit:
1.0 mm (0.04 in)
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9
EBU24965Checking the wheel hub bearingsThe front and rear wheel hub bearings must be
checked at the intervals specified in the periodic
maintenance chart. If there is play in a wheel hub
or if a wheel does not turn smoothly, have a
Yamaha dealer check the wheel hub bearings.EBU24974Lubricating the drive shaft universal
jointThe drive shaft universal joint must be lubricated
at the intervals specified in the periodic mainte-
nance chart.
TIPFor parts equipped with a grease nipple, use a
grease gun. EBU25024Checking the stabilizer bushesThe stabilizer bushes must be checked for cracks
or damage at the intervals specified in the periodic
maintenance chart.Recommended lubricant: Lithium-soap-based grease1. Grease nipple
1
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9
EBU30806Replacing a fuse
If an electrical problem is suspected, check the
fuse and replace it if necessary as follows.NOTICEECB00641To prevent accidental short-circuiting, turn off
the main switch when checking or replacing a
fuse. 1. Turn off all electrical systems. (See page 5-1.)
1. Fuel injection system spare fuse
2. Fuel injection system fuse
3. Main fuse
4. EPS fuse (equipped models)
5. Fuse box
1
2
3
4
5
1. Auxiliary DC jack fuse
2. Four-wheel-drive motor fuse
3. Ignition fuse
4. Radiator fan motor fuse
5. Signaling system fuse
6. Headlight fuse
7. Spare fuse
1
2
34
5
6
7
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92. Remove the seat. (See page 5-18.)
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, andthen 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: 10.0 A (YFM450FWBD)
3.0 A (YFM450FWB)
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 (YFM450FWBD)
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9
EBU25615Replacing the brake/tail light bulbIf the brake/tail light bulb burns out, replace it as
follows.1. Remove the brake/tail light bulb holder (to- gether with the bulb) by turning it counter-
clockwise.
2. Remove the burnt-out bulb by pushing it in and turning it counterclockwise. 3. Insert a new bulb into the bulb holder, push it
in, and then turn it clockwise until it stops.
4. Install the bulb holder (together with the bulb) by turning it clockwise.
EBU25653Removing a wheel1. Park the ATV on a level surface.
2. Loosen the wheel nuts.
1. Brake/tail light bulb holder
1
1. Brake/tail light bulb
1
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9-64
93. Elevate the ATV and place a suitable stand
under the frame.
4. Remove the nuts from the wheel.
5. Remove the wheel.
EBU36243Installing a wheel1. Install the wheel with the arrow mark pointing in the forward rotating direction of the wheel,
and then install the wheel nuts.
TIPFor models with tapered nuts: be sure to install the
nuts with their tapered side towards the wheel.
1. Wheel nut
1
1
1. Arrow mark
2. Forward rotating direction
3. Wheel nut
1
2
3
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9-65
9
2. Lower the ATV to the ground.
3. Tighten the wheel nuts to the specified
torques.
EBU25741TroubleshootingAlthough 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 charts represent
quick and easy procedures for checking these vi-
tal systems yourself. However, should your ATV
require any repair, take it to a Yamaha dealer,
whose skilled technicians have the necessary
tools, experience, 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
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. Tapered nutTightening torques:Front wheel nut:55 N·m (5.5 kgf·m, 41 lb·ft)
Rear wheel nut: 55 N·m (5.5 kgf·m, 41 lb·ft)1
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10
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 plac-
es.
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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