warning YAMAHA YFZ450 2012 Service Manual

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8
3. If the coolant is at or below the minimum level
mark, remove the coolant reservoir cap, add
coolant or distilled water to the maximum level
mark, and then install the reservoir cap.
NOTICE: If coolant is not available, use
distilled water or soft tap water instead. Do
not use hard water or salt water since they
are harmful to the engine. If water has
been used instead of coolant, replace it
with coolant as soon as possible, other-
wise the cooling system will not be pro- tected against frost and corrosion. If water
has been added to the coolant, have a
Yamaha dealer check the antifreeze con- tent of the coolant as soon as possible,
otherwise the effectiveness of the coolant
will be reduced.
[ECB01011]
TIP
The radiator fan is automatically switched on or
off according to the coolant temperature in the
radiator.
If the engine overheats, see page 8-58 for fur-
ther instructions.EBU23564To change the coolant
WARNING
EWB01890Wait for the engine and radiator to cool before
removing the radiator cap. You could be
burned by hot fluid and steam blown out under
1. Maximum level mark
2. Minimum level mark
3. Coolant reservoir
4. Coolant reservoir cap
1
2 4
3
Coolant reservoir capacity (up to the maxi-
mum level mark):
0.29 L (0.31 US qt, 0.26 Imp.qt)
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8-26
88. Wash the sponge material gently but thor-
oughly in solvent. WARNING! Always use
parts cleaning solvent to clean the sponge
material. Never use low-flash-point sol-
vents or gasoline to clean the sponge ma-
terial because the engine could catch fire
or explode.
[EWB01941]
9. Squeeze the excess solvent out of the sponge material and let it dry. NOTICE: Do not twist
the sponge material when squeezing it.
[ECB00441]
10. Check the sponge material and replace it if damaged.
11. Apply Yamaha foam air filter oil or other qual- ity foam air filter oil to the sponge material.TIPThe sponge material should be wet but not drip-
ping.12. Pull the sponge material over the air filter ele-ment frame.
13. Apply all-purpose grease to the air filter ele- ment seat.
1. Sponge material
2. Air filter element frame
1
2
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8
WARNING
EWB02380Never run the engine in an enclosed area when
purging the spark arrester, otherwise it could
cause injury to the eyes, burns, carbon monox-
ide poisoning, possibly leading to death, and
start a fire.
Always let the exhaust system cool prior to
touching exhaust components.
Always wear eye protection, and make sure
no one is behind the ATV.
Make sure there are no combustible materi-
als in the area.EBU23940Adjusting the carburetor The carburetor should be checked and, if neces-
sary, adjusted at the intervals specified in the peri-
odic maintenance and lubrication chart. The
carburetor is an important part of the engine and
requires very sophisticated adjustment. Therefore,
most carburetor adjustments should be left to aYamaha dealer, who has the necessary profes-
sional knowledge and experience. The adjustment
described in the following section, however, may
be performed by the owner as part of routine main-
tenance.
NOTICEECB00480The carburetor has been set and extensively
tested at the Yamaha factory. Changing these
settings without sufficient technical knowl-
edge may result in poor performance of or
damage to the engine.EBU24030Checking the engine idling speed A special tester is needed to check the engine
idling speed on this model.
Therefore, take the ATV to a Yamaha dealer to
have the engine idling speed checked and adjust-
ed.
Tightening torque:
Purging bolt:27 Nm (2.7 m ·kgf, 20 ft· lbf)Engine idling speed:
1750 –1850 r/min
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8
EBU29601Brakes Replacement of brake components requires pro-
fessional knowledge. Brake service should be per-
formed by a Yamaha dealer.
WARNING
EWB02571Operating with improperly serviced or adjust-
ed brakes could lead to a loss in braking ability
and an accident.EBU24130Checking the front and rear brake pads The front and rear brake pads must be checked for
wear at the intervals specified in the periodic main-
tenance and lubrication chart.EBU27711Front brake pads
Each brake pad is provided with wear indicator
grooves, which allow you to check the brake pad
wear without having to disassemble the brake. To
check the brake pad wear, check the wear indica-
tor grooves. If a brake pad has worn to the point
that the wear indicator grooves are almost in con-
tact with the disc plate, have a Yamaha dealer re-
place the brake pads as a set.
TIPThe wheels need to be removed to check the
brake pads. (See page 8-54.)EBU29831Rear brake pads
Each brake pad is provided with wear indicator
grooves, which allow you to check the brake pad
wear without having to disassemble the brake. To
check the brake pad wear, check the wear indica-
tor grooves. If a brake pad has worn to the point
that the wear indicator grooves have almost disap-
peared, have a Yamaha dealer replace the brake
pads as a set.1. Wear indicator groove
U1PD60E0.book Page 32 Monday, June 13, 2011 2:57 PM

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8
5. Install the brake fluid reservoir bracket bolt.
6. Install the seat.
WARNING
EWB02720Improper maintenance can result in loss of
braking ability. Observe these precautions:

Insufficient brake fluid may allow air to enter
the brake system, reducing braking perfor-
mance.
Clean the filler cap before removing. Use
only DOT 4 brake fluid from a sealed contain-
er.
Use only the specified brake fluid; otherwise,
the rubber seals may deteriorate, causing
leakage.
Refill with the same type of brake fluid. Add-
ing a brake fluid other than DOT 4 may result
in a harmful chemical reaction.
Be careful that water does not enter the
brake fluid reservoir when refilling. Water
will significantly lower the boiling point of
the fluid and may result in vapor lock.NOTICEECB01160Brake fluid may damage painted surfaces or
plastic parts. Always clean up spilled fluid im-
mediately.As the brake pads wear, it is normal for the brake
fluid level to gradually go down. A low brake fluid
level may indicate worn brake pads and/or brake
system leakage; therefore, be sure to check the
1. Frame
2. Projection
3. Brake fluid reservoir bracket
4. BoltSpecified brake fluid:
DOT 4
2 3
1 4
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8
TIPIf the cable length cannot be adjusted to specifica-
tion, consult a Yamaha dealer.6. Tighten the locknut on the brake cable.
7. Slide the rubber cover to its original position.
8. Turn in the adjusting bolt at the rear brake cal-iper until it feels tight, then turn it out 1/8 turn
and tighten its locknut to the specified torque.
NOTICE: When tightening the locknut, hold the adjusting bolt with a wrench so
that it does not turn together with the lock-
nut.
[ECB00521]
WARNING
EWB02090Operating with improperly serviced or adjust-
ed brakes could cause the brakes to malfunc-
tion, resulting in reduced braking
performance. This could increase the chance
of a collision or accident. After adjusting the
parking brake free play, block the rear of the
ATV off the ground and spin the rear wheels.
Check to make sure there is no brake drag. If
brake drag is noticed, perform the adjustment
again.EBU24743Brake light switches The brake light, which is activated by the brake
pedal and brake lever, should come on just before
braking takes effect.
1. Locknut
2. Parking brake free play adjusting nut
3. Rubber cover
(a)
(b)
1
2
3
Tightening torque: Locknut (rear brake caliper):16 Nm (1.6 m ·kgf, 12 ft· lbf)
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8-44
8essary. If a cable is damaged or does not move
smoothly, have a Yamaha dealer check or replace
it.
WARNING
EWB02581
Inspect cables frequently and replace if dam-
aged. Corrosion can result when the cable
sheaths become damaged, and cables can
also become frayed or kinked, which could
restrict the operation of controls and lead to
an accident or injury.
Always make sure all control cables work
smoothly before you begin riding in cold
weather. If the control cables are frozen or do
not work smoothly, you could be unable to
control the ATV, which could lead to an acci-
dent or collision.
EBU24922Checking and lubricating the brake and
clutch levers The operation of the brake and clutch levers
should be checked before each ride, and the lever
pivots should be lubricated if necessary.
Brake lever
Recommended lubricant:
Yamaha Chain and Cable Lube or engine oilRecommended lubricants: Brake lever:Silicone grease
Clutch lever: Lithium-soap-based grease
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8
EBU29189Battery The 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
EWB02160Battery electrolyte is poisonous and danger-
ous, as it contains sulfuric acid, which can
cause 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 ig-
nition away. Ventilate when charging or using
in an enclosed space.KEEP OUT OF REACH OF CHILDREN.
NOTICEECB00620Never 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. Remove the battery holding plate by removing the bolts.
3. 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.
[ECB01001]
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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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8-56
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