YAMAHA YFZ450 2012 Owners Manual

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8
2. 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.
[EWB02172]
3. Turn the key to “ ON” and turn on the electrical
circuits to check if the devices operate.
4. If the fuse immediately blows again, have a Yamaha dealer check the electrical system.EBU30680Replacing a headlight bulb If a headlight bulb burns out, replace it as follows.1. Remove the headlight unit by removing the bolts. 2. Disconnect the headlight coupler.
3. Remove the headlight bulb holder cover.
Specified fuse:
15.0 A
1. Headlight unit
2. Bolt
2 1
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84. Remove the headlight bulb holder by pushing
it in and turning it counterclockwise, and then
remove the burnt-out bulb. 5. Place a new headlight bulb into position.
NOTICE: Do not touch the glass part of the
headlight bulb to keep it free from oil, oth-
erwise the transparency of the glass, the
luminosity of the bulb, and the bulb life will
be adversely affected. Thoroughly clean
off any dirt and fingerprints on the head-
light bulb using a cloth moistened with al-
cohol or thinner.
[ECB00651]
1. Headlight bulb holder cover
2. Headlight coupler
1
2
1. Headlight bulb holder
1
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8
6. Install the headlight bulb holder by pushing it
in and turning it clockwise.
7. Install the headlight bulb holder cover.
8. Connect the headlight coupler.
9. Install the headlight unit by installing the bolts.
10. Adjust the headlight beam if necessary.
EBU25551Adjusting a headlight beam NOTICEECB00690It is advisable to have a Yamaha dealer make
this adjustment.
To raise a headlight beam, turn the headlight beam
adjusting screw in direction (a).
To lower a headlight beam, turn the adjusting
screw in direction (b).EBU25613Replacing the tail/brake light bulb If the tail/brake light bulb burns out, replace it as
follows. 1. Remove the tail/brake light bulb holder (to- gether with the bulb) by turning it counter-
clockwise.
1. Do not touch the glass part of the bulb.
1
1. Headlight beam adjusting screw
1 (a)
(b)
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82. 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.
EBU25651Removing a wheel 1. Place the ATV on a level surface.
2. Loosen the wheel nuts.
1. Tail/brake light bulb holder
1
1. Tail/brake light bulb holder
2. Tail/brake light bulb
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8
Front
Rear
3. Elevate the ATV and place a suitable stand
under the frame.
4. Remove the nuts from the wheel.
5. Remove the wheel.
EBU25661Installing a wheel 1. Place the ATV on a level surface.
2. Install the wheel and the nuts.
3. Lower the ATV to the ground.
4. Tighten the wheel nuts to the specified torques.EBU25740Troubleshooting 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.
1. Nut
1. Nut
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)
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8The following troubleshooting charts represent
quick and easy procedures 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
EWB02280Do 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.U1PD60E0.book Page 56 Monday, June 13, 2011 2:57 PM

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8
EBU25784Troubleshooting charts Starting problems or poor engine performance
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 have a Yamaha dealer charge
the battery if necessary.
DryWet
Open the throttle halfway and operate
the electric starter.
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8Engine overheating
WARNING
EWB02290Wait for the engine and radiator to cool before removing the radiator cap. You could be burned by
hot fluid and steam blown out under pressure. Always put a thick rag over the cap when opening.
Allow any remaining pressure to escape before completely removing the cap.TIPIf coolant is not available, tap water can be temporarily used instead, provided that it is changed to the rec-
ommended coolant as soon as possible.Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer check
and repair the cooling system.Add coolant. (See TIP.)
Start the engine. If the engine overheats again, have a
Yamaha dealer check and repair the cooling system.
There is
leakage.
There is
no leakage.
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9
EBU25860
CLEANING AND STORAGE
EBU25902Cleaning Frequent, 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 chain, sprockets or wheel ax-
les.
3. Rinse the dirt and degreaser off with a garden hose. Use only enough pressure to do the job.
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 the linings.
[EWB02311]
NOTICE: Excessive water pressure may cause water seepage and deteriora-
tion of wheel bearings, brakes, transmis-
sion seals and electrical devices. Many
expensive repair bills have resulted from
improper high-pressure detergent applica-
tions such as those available in coin-oper-
ated car washers.
[ECB00711]
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. 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
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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9
EBU25933Storage Short-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.
[ECB00721]
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 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 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-
Specified amount:
7.5 ml of stabilizer to each liter of fuel (or 1
oz of stabilizer to each gallon of fuel)U1PD60E0.book Page 2 Monday, June 13, 2011 2:57 PM