stop start YAMAHA YFZ450 2007 Owners Manual

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EBU17680
DESCRIPTION
EBU17690
Left view
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Right view
1. Headlights
2. Fuel cock
3. Starter (choke)
4. Throttle stop screw
5. Fuse
6. Tail/brake light
7. Coolant reservoir
8. Shift pedal
9. Engine oil tank
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1. Spark arrester
2. Seat
3. Fuel tank cap
4. Radiator cap
5. Oil filter element
6. Brake pedal
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EBU17802
Indicator light and warning light
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Neutral indicator light “”
This indicator light comes on when the transmis-
sion is in the neutral position.
EBU17930
Coolant temperature warning light “”
This warning light comes on when the engine over-
heats. When this occurs during operation, stop the
engine as soon as it is safe to do so and allow it to
cool down for about 10 minutes.The electrical circuit of the warning light can be
checked according to the following procedure.
1. Set the engine stop switch to “ ” and turn the
key to “ON”.
2. Shift the transmission into the neutral position
or pull the clutch lever.
3. Push the start switch. If the warning light does
not come on while the start switch is pushed,
have a Yamaha dealer check the electrical cir-
cuit.
CAUTION:

ECB00010

The engine may overheat if the ATV is over-
loaded. In this case, reduce the load to spec-
ification.

Start the engine after making sure that the
warning light is out. Continuous use while
the warning light is on may cause damage to
the engine.
1. Neutral indicator light “N”
2. Coolant temperature warning light “ ”
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EBU18060
Handlebar switches
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Engine stop switch “ENG. STOP”
Set this switch to “RUN” before starting the engine.
The engine stop switch controls the ignition and
stops the engine when it is running. Use this switch
to stop the engine in an emergency situation. The
engine will not start or run when this switch is set
to “OFF”.
EBU18090
Start switch “START”
Push this switch to crank the engine with the start-
er.CAUTION:

ECB00050
See the starting instructions on page 6-1 prior
to starting the engine.
EBU18120
Light switch “LIGHTS”
Set this switch to “LO” to turn on the low beams
and the taillight. Set the switch to “HI” to turn on the
high beams and the taillight. Set the switch to
“OFF” to turn off all the lights.
NOTE:

The headlights and the taillight can be turned on
only when the engine is running.
EBU18280
Throttle lever
Once the engine is running, movement of the throt-
tle lever will increase the engine speed.
Regulate the speed of the ATV by varying the
throttle position. Because the throttle is spring-
loaded, the ATV will decelerate, and the engine will
1. Light switch “LIGHTS”
2. Engine stop switch “ENG. STOP”
3. Start switch “START”
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EBU19880
OPERATION
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Read the Owner’s Manual carefully before riding
the ATV.
WARNING

EWB00630
Read the Owner’s Manual carefully to become
familiar with all controls in order to help pre-
vent any loss of control, which could cause an
accident or injury. If there is a control or func-
tion you do not understand, ask your Yamaha
dealer.
EBU20101
Starting a cold engine
WARNING

EWB00640
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.
CAUTION:

ECB00150
See the “Engine break-in” section on page 6-5
prior to operating the engine for the first time.
1. Set the parking brake.
2. Turn the fuel cock to “ON”.
3. Turn the main switch to “ON” and the engine
stop switch to “RUN”.
4. Shift the transmission into neutral. The neutral
indicator light should come on. If the indicator
light does not come on, have a Yamaha deal-
er check the electrical circuit.
NOTE:

This model is equipped with an ignition circuit cut-
off system. The engine can be started under the
following conditions.

The transmission is in neutral.

The clutch is disengaged with the transmission
in gear. However, it is recommended to shift into
neutral before starting the engine.
5. Use the starter (choke) in reference to the fig-
ure:

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attempt.
7. If the engine is started with the starter (choke)
in position (1), the starter (choke) should be
returned to position (2) to warm up the engine.
If the engine is started with the starter (choke)
in position (2), keep the starter (choke) in this
position to warm up the engine.
CAUTION:

ECB00160
For maximum engine life, always warm the en-
gine up before starting off. Never accelerate
hard when the engine is cold!
8. Continue warming up the engine until it idles
smoothly, then return the starter (choke) to
position (3) before riding.
NOTE:

The engine is warm when it responds normally to
the throttle with the starter (choke) turned off.
EBU20291
Starting a warm engine
Follow the same procedure as for starting a cold
engine, with the exception that the starter (choke)
is not required when the engine is warm. Instead,
start the engine with the throttle slightly open.
EBU20520
Shifting
This ATV has a 5-speed forward transmission. The
transmission allows you to control the amount of
power you have available at a given speed or for
starting, accelerating, climbing hills, etc.
To shift into neutral, return the throttle lever to the
closed position, apply the clutch, and then repeat-
edly depress the shift pedal until it stops.
When it stops, it will be in first gear. Raise the pedal
slightly to reach the neutral position.
EBU20570
To start out and accelerate
1. Release the throttle lever.
1. Shift pedal
2. Neutral position
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If you are climbing a hill and you find that you have
not properly judged your ability to make it to the
top, you should turn the ATV around while you still
have forward motion (provided you have the room
to do so) and go down the hill.
WARNING

EWB01600
Never attempt to turn the ATV around on any
hill until you have mastered the turning tech-
nique as described in the Owner’s Manual on
level ground. Be very careful when turning onany hill. Avoid crossing the side of a steep hill
if possible.
When crossing the side of a hill:

Always follow proper procedures as de-
scribed in the Owner’s Manual.

Avoid hills with excessively slippery or loose
surfaces.

Shift your weight to the uphill side of the
ATV.
If your ATV has stalled or stopped and you believe
you can continue up the hill, restart carefully to

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make sure you do not lift the front wheels which
could cause you to lose control. If you are unable
to continue up the hill, dismount the ATV on the up-
hill side. Physically turn the ATV around and then
descend the hill.
If you start to roll backwards, DO NOT apply the
rear brake to stop or try to put the ATV in gear. The
ATV could easily tip over backwards. Instead, ap-
ply the front brake gradually, or dismount the ATV
immediately on the uphill side.
WARNING

EWB01731
Use the proper gear and maintain a steady
speed when climbing a hill.
If you lose all forward speed:

Keep weight uphill.

Apply the brakes.

Lock the parking brake after you are
stopped.
If you begin rolling backwards:

Keep weight uphill.

Never apply the rear brake while rolling
backwards. Apply the front brake.

When fully stopped, apply the rear brake as
well, and then lock the parking brake.
Dismount on uphill side or to a side if pointedstraight uphill. Turn the ATV around and re-
mount, following the procedure described in
the Owner’s Manual.
RIDING DOWNHILL
When riding your ATV downhill, shift your weight
as far to the rear and uphill side of the ATV as pos-
sible. Move back on the seat and sit with your arms
straight. Choose a low gear which will allow the en-
gine compression to do most of the braking for
you. Improper braking may cause a loss of trac-

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slide. Applying the brakes or accelerating is not
recommended until you have corrected the slide.
With practice, over a period of time, skill at con-
trolled sliding can be developed. The terrain
should be chosen carefully before attempting such
maneuvers, since both stability and control are re-
duced. Bear in mind that sliding maneuvers should
always be avoided on extremely slippery surfaces
such as ice, since all control may be lost.
WARNING

EWB01661
Learn to safely control skidding or sliding by
practicing at low speeds and on level, smoothterrain.
On extremely slippery surfaces, such as ice,
go slowly and be very cautious in order to re-
duce the chance of skidding or sliding out of
control.
WHAT TO DO IF...
This section is designed to be a reference guide
only. Be sure to read each section on riding tech-
niques completely.
WHAT TO DO...

If your ATV doesn’t turn when you want it to:
Bring the ATV to a stop and practice the turning
maneuvers again. Be sure you are putting your
weight on the footboard to the outside of the
turn. Position your weight over the front wheels
for better control. (See page 7-12.)

If your ATV begins to tip while turning:
Lean more into the turn to regain balance. If nec-
essary, gradually let off the throttle and/or steer
to the outside of the turn. (See page 7-12.)

If your ATV starts to slide sideways:
Steer in the direction of the slide if you have the
room. Applying the brakes or accelerating is not
recommended until you have corrected the

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slide. (See page 7-20.)

If your ATV can’t make it up a hill you are trying
to climb:
Turn the ATV around if you still have forward
speed. If not, stop, dismount on the uphill side of
the ATV and physically turn the ATV around. If
the ATV starts to slip backwards, DO NOT USE
THE REAR BRAKE – the ATV may tip over on
top of you. Dismount the ATV on the uphill side.
(See page 7-14.)

If your ATV is traversing a sloping surface:
Be sure to ride with your weight positioned to-
wards the uphill side of the ATV to maintain
proper balance. If the ATV starts to tip, steer
down the hill (if there are no obstacles in your
way) to regain balance. If you discover that the
ATV is going to tip over, dismount on the uphill
side. (See page 7-14.)

If your ATV encounters shallow water:
Ride slowly and carefully through slow moving
water, watching for obstacles. Be sure to let wa-
ter drain from the ATV and CHECK YOUR
BRAKES FOR PROPER OPERATION when
you come out of the water. Do not continue to
ride your ATV until you have regained adequate
braking ability. (See page 7-18.)

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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.
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.
EBU23940
Adjusting 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 a
Yamaha 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.
CAUTION:

ECB00480
The carburetor has been set and extensively
tested at the Yamaha factory. Changing these
1. Purging bolt
2. Gasket
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