engine YAMAHA YFZ450 2006 Owner's Manual

5-15
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8Do not overfill the fuel tank. Fuel expands
when it heats up. If the fuel tank is over-
filled, fuel could spill out due to heat from
the engine or the sun.
8Be careful not to spill fuel, especially on
the engine or exhaust pipe which can
cause a fire and severe injury. Wipe up
any spilled fuel immediately.
8Do not refuel right after the engine has
been running and is still very hot.
8Be sure the fuel tank cap is closed secure-
ly.q
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1. Fuel tank filler tube 2. Fuel level1. Tube de remplissage du réservoir de carburant
2. Niveau de carburant
1. Tubo de llenado del depósito de combustible
2. Nivel de combustible
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5-17
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Engine oil
Make sure the engine oil is at the specified level.
Add oil as necessary. (See page 8-25.)
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8In order to prevent clutch slippage (since
the engine oil also lubricates the clutch),
do not mix any chemical additives. Do not
use oils with a diesel specification of “CD”
or oils of a higher quality than specified. In
addition, do not use oils labeled “ENERGY
CONSERVING II” or higher.
8Make sure that no foreign material enters
the crankcase.
Recommended engine oil type and quantity:
See page 10-2.
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5-19
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Coolant
Check the coolant level in the coolant reservoir
when the engine is cold. (The coolant level will
vary with engine temperature.) The coolant level
is satisfactory if it is between the minimum and
maximum level marks on the coolant reservoir. If
the coolant level is at or below the minimum
level mark, add distilled water to bring the level
up to the maximum level mark. Change the
coolant every two years. (See pages 8-43–8-53
for details.)
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Hard water or salt water is harmful to the
engine. You may use soft water if you cannot
get distilled water.
Coolant reservoir capacity
(up to the maximum level mark):
0.29 L
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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.
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Chain
Check the general condition of the chain and
check the chain slack before every ride.
Lubricate and adjust the chain as necessary.
(See pages 8-105–8-113 for details.)
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Throttle lever
Check to see that the throttle lever operates cor-
rectly. It must open smoothly and spring back to
the idle position when released. Have a Yamaha
dealer repair as necessary for proper operation.
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6-3
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Starting a cold engine
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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
accident or collision.
1. Apply 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.
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6-5
NOTE:
This model is equipped with an ignition circuit
cut-off system. The engine can be started under
the following conditions.
8When the transmission is in neutral.
At this time the neutral indicator light should
come on. If the light does not come on, ask a
Yamaha dealer to inspect it.
8When the clutch is disengaged with the trans-
mission in any position. However, it is recom-
mended to shift into neutral before starting the
engine.
5. Use the starter (choke) in reference to the
figure:
Position
1: Cold engine start-
ambient temperature below 5 ° C.
Position 2: Cold engine start-
ambient temperature at 0 ° C -
30 ° C and warming up position.
Position 3: Cold engine start-
ambient temperature above 25 ° C
and warm engine start position.
1. Fully open 2. Half open
3. Closed a. Starter (choke)
1. Pleine course 2. Mi-course
3. Fermé a. Starter (choke)
1. Abierto completamente 2. Semiabierto
3. Cerrado a. Starter (choke)
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6-7
6. Completely close the throttle lever and start
the engine by pushing the start switch.
NOTE:
If the engine fails to start, release the start
switch, then push it again. Pause a few seconds
before the next attempt. Each cranking should
be as short as possible to preserve battery ener-
gy. Do not crank the engine more than 10 sec-
onds on each attempt.
7. If the engine is started with the starter
(choke) in position 1, the starter (choke)
should be returned to position 2to 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.
8. Continue warming up the engine until it
idles smoothly and return the starter
(choke) to position 3before riding.
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See the “Engine break-in” section prior to
operating the engine for the first time.
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Starting a warm engine
To start a warm engine, refer to the “Starting a
cold engine” section. The starter (choke) should
not be used. The throttle should be opened
slightly.
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Warming up
To get maximum engine life, always warm up
the engine before starting off. Never accelerate
hard with a cold engine! To see whether or not
the engine is warm, check if it responds to the
throttle normally with the starter (choke) turned
off.
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6-11
1. Shift pedal N. Neutral position1. Pédale de sélection N. Point mort1. Pedal del cambio N. Punto muerto
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Shifting
This model 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 its original position, apply the clutch and
repeatedly depress the shift pedal until it stops.
When it stops, it will be in first gear. Raise the
pedal slightly to neutral.
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8Do not coast for long periods with the
engine off, and do not tow the machine a
long distance. Even in neutral position, the
transmission is only properly lubricated
when the engine is running. Inadequate
lubrication may cause damage.
8Always use the clutch when changing
gears. The engine, transmission and drive
train are not designed to withstand the
shock of forced shifting and can be dam-
aged by shifting without the clutch.
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6-13
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To start out and accelerate:
1. Release the throttle lever, and then release
the parking brake.
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Always close the throttle while shifting
gears. Otherwise, damage to the engine and
drive train may result.
2. Pull the clutch lever to disengage the
clutch.
3. Shift into first gear.
4. Open the throttle gradually and at the
same time, release the clutch lever slowly.
5. Once the machine has attained adequate
speed, release the throttle, and at the
same time, quickly pull in the clutch lever.
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