warning YAMAHA YFZ450R 2009 Workshop Manual

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7. Start the engine and rev it up approximately
twenty times while momentarily creating ex-
haust system back pressure by blocking the
end of the muffler with a shop towel.
8. Stop the engine and allow the exhaust pipe to
cool.
9. Install the purging bolt and tighten it to the
specified torque.
WARNING

EWB02380
Never 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.
EBU24045
Adjusting the throttle cable free play
The throttle cable free play should be checked
and, if necessary, adjusted at the intervals speci-
fied in the periodic maintenance and lubrication
chart.
The throttle cable free play should measure 2.0–
4.0 mm (0.08–0.16 in) at the throttle lever. Period-
ically check the throttle cable free play and, if nec-
essary, adjust it as follows.
TIP

The engine idling speed must be checked, and ad-
1. Purging bolt
2. Gasket
Tightening torque:
Purging bolt:
27 Nm (2.7 m·kgf, 19 ft·lbf)
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Refill with the same type of brake fluid. Mixing
fluids may result in a harmful chemical reaction
and lead to poor braking performance.

Be careful that water does not enter the brake
fluid reservoir when refilling. Water will signifi-
cantly lower the boiling point of the fluid and may
result in vapor lock.

Brake fluid may deteriorate painted surfaces or
plastic parts. Always clean up spilled fluid imme-
diately.

As the brake pads wear, it is normal for the brake
fluid level to gradually go down. However, if the
brake fluid level goes down suddenly, have a
Yamaha dealer check the cause.
EBU24291
Changing the brake fluid
Have a Yamaha dealer change the brake fluid at
the intervals specified in the TIP after the periodic
maintenance and lubrication chart. In addition,
have the oil seals of the master cylinders and cali-
pers as well as the brake hoses replaced at the in-
tervals listed below or whenever they are damaged
or leaking.

Oil seals: Replace every two years.

Brake hoses: Replace every four years.
EBU24393
Checking the front brake lever free play
The brake lever free play must be checked at the
intervals specified in the periodic maintenance and
lubrication chart. The brake lever should have no
free play as shown. If there is free play, have a
Yamaha dealer check the brake system.WARNING
EWB02471
Operating with improperly serviced or adjust-
ed brakes could cause loss of braking ability,
which could lead to an accident.
After servicing:
1. Brake lever free play
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Make sure the brakes operate smoothly and
that there is no free play.

Make sure the brakes do not drag.

Make sure the brakes are not spongy. All air
must be bled from the brake system.
Replacement of brake components requires
professional knowledge. These procedures
should be performed by a Yamaha dealer.
EBU24611
Checking the brake pedal position
The brake pedal position must be checked and, if
necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
The top of the brake pedal should be positioned
11.7 mm (0.46 in) below the top of the footrest as
shown. If the brake pedal is not positioned as spec-
ified, have a Yamaha dealer adjust it.
WARNING
EWB02110
Operating with improperly serviced or adjust-
ed brakes could cause loss of braking ability,
which could lead to an accident.
After servicing:

Make sure the brakes operate smoothly and
that the brake pedal position is correct.

Make sure the brakes do not drag.

Make sure the brakes are not spongy. All air
must be bled from the brake system.
Replacement of brake components requires
professional knowledge. These procedures
1. Brake pedal position
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6. 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

ECB00520
When tightening the locknut, hold the adjust-
ing bolt with a wrench so that it does not turn
together with the locknut.
WARNING

EWB02090
Operating 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.
EBU24740
Brake light switches
The operation of the brake light switches must be
checked and, if necessary, adjusted at the inter-
vals specified in the periodic maintenance and lu-
brication chart.
The brake light switch for the brake pedal can be
adjusted as follows, but the other brake light
switches should be adjusted by a Yamaha dealer.
TIP

The brake light switch is properly adjusted when
the brake light comes on just before braking takes
effect.
Turn the adjusting nut while holding the brake light
switch in place. To make the brake light come on
earlier, turn the adjusting nut in direction (a). To
make the brake light come on later, turn the adjust-
ing nut in direction (b). Tightening torque:
Locknut (rear brake caliper):
16 Nm (1.6 m·kgf, 11 ft·lbf)

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NOTICE

ECB00570
To prevent damaging the O-rings, do not clean
the drive chain with steam cleaners, high-pres-
sure washers or inappropriate solvents.
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive chain with a
special O-ring chain lubricant.
NOTICE

ECB00580
Do not use engine oil or any other lubricants
for the drive chain, as they may contain sub-
stances that could damage the O-rings.
EBU24900
Checking and lubricating the cables
The operation and the condition of all control ca-
bles should be checked before each ride, and the
cables and cable ends should be lubricated if nec-
essary. If a cable is damaged or does not move
smoothly, have a Yamaha dealer check or replace
it.
WARNING
EWB02130
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 re-
strict the operation of controls and lead to an
accident or injury.
EBU24922
Checking 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.
Recommended lubricant:
Engine oil
Recommended lubricants:
Brake lever:
Silicone grease
Clutch lever:
Lithium-soap-based grease

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WARNING

EWB02160
Battery 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.
To remove the battery
1. Remove the seat. (See page 4-10.)
2. Remove the battery holding plate by removing
the bolts.
3. Disconnect the negative battery lead first,
then the positive battery lead by removingtheir bolt.
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 electri-
cal accessories.

1. Bolt
2. Battery holding plate
3. Negative battery lead (black)
4. Positive battery lead (red)
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EBU25242
Replacing the fuse
The fuse holder is located under the seat. (See
page 4-10.)
If the fuse is blown, replace it as follows.
1. Turn the key to “OFF” and turn off all electrical
circuits.
NOTICE

ECB00640
To prevent accidental short-circuiting, turn off
the main switch when checking or replacing a
fuse.
2. Remove the blown fuse, and then install a
new fuse of the specified amperage.
WARNING

EWB02171
Always use a fuse of the specified rating, and
never use a substitute object in place of the
proper fuse. An improper fuse or a substitute
object can cause damage to the electrical sys-
tem, which could lead to a fire.
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.
EBU29460
Replacing a headlight bulb
If a headlight bulb burns out, replace it as follows.
1. Remove panel E. (See page 8-8.)
2. Remove the headlight bulb holder cover.
1. Fuse
2. Spare fuse
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Specified fuse:
20.0 A

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3. Remove the headlight bulb holder by pushing
it in and turning it counterclockwise, and then
remove the burnt-out bulb.
WARNING

EWB02230
Do not touch a headlight bulb when it is on or
immediately after it is turned off. You can be
burned or a fire could start if the bulb touches
something flammable. Wait for the bulb to cool
before touching or removing it.
4. Place a new headlight bulb into position.
1. Headlight bulb holder cover
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1. Headlight bulb holder
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WARNING

EWB02280
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.

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Engine overheating
WARNING

EWB02290
Wait 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.
TIP

If 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.