2013 YAMAHA YFZ450 engine

4-11
4ON
With the fuel cock lever in this position, fuel flows
to the carburetor. Turn the fuel cock lever to this
position when starting the engine and riding. RES
This indicates reserve. With the fuel cock lever in
this position, the fuel reserve is made available.
Turn the fuel cock lever to this position if you run
out of fuel while riding. When this occurs, refuel as
soon as possible and be sure to turn the fuel cock
lever back to “ON”!
EBU18840Starter (choke) Starting a cold engine requires a richer air-fuel mix-
ture, which is supplied by the starter (choke).
Move the starter (choke) in direction (a) to turn on
the starter (choke).
1. Arrow mark positioned over “ON”
1
1. Arrow mark positioned over “RES”
1
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4-12
4
Move the starter (choke) in direction (b) to turn off
the starter (choke).
See the “Starting a cold engine” section on page
6-1 for proper operation.
EBU18892Seat To remove the seat
Insert your hand under the rear fender near the
rear of the seat, pull the seat lock lever and pull up
the seat at the rear. To install the seat
Insert the projections on the front of the seat into
the seat holders and push down on the seat at the
rear. Make sure that the seat is securely fitted.1. Starter (choke)
1(a)
(b)
1. Seat lock lever
1
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5-1
5
EBU19201
PRE-OPERATION CHECKS
EBU19224Inspect your vehicle each time you use it to make sure the vehicle is in safe operating condition. Always
follow the inspection and maintenance procedures and schedules described in the Owner’s Manual.
WARNING
EWB00481Failure to inspect or maintain the vehicle properly increases the possibility of an accident or equip-
ment damage. Do not operate the vehicle if you find any problem. If a problem cannot be corrected
by the procedures provided in this manual, have the vehicle inspected by a Yamaha dealer.Before using this vehicle, check the following points:
ITEMROUTINE PAGE
Fuel Check fuel level in fuel tank, and add recommended fuel if neces-
sary.
Check fuel line for leakage. Correct if necessary. 4-8, 5-4
Engine oil Check oil level in engine oil tank, and add recommended oil to spec-
ified level if necessary.
Check ATV for oil leakage. Correct if necessary. 5-4, 8-14
Coolant Check coolant level in reservoir, and add recommended coolant to
specified level if necessary.
Check cooling system for leakage. Correct if necessary. 5-4, 8-20
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5-4
5
EBU19541Fuel Make sure that there is sufficient fuel in the tank.
(See page 4-8.)EBU19560Engine oil Make sure that the engine oil is at the specified lev-
el. Add oil as necessary. (See page 8-14.)EBU19631Coolant Make sure that the coolant is at the specified level.
Add coolant as necessary. (See page 8-20.)TIPThe coolant level must be checked on a cold en-
gine since the level varies with engine tempera-
ture.EBU19712Front and rear brakes Brake lever and brake pedal●Check that there is no free play in the brake le-
ver. If there is free play, have a Yamaha dealer
check the brake system.
●Check for correct brake pedal height. (See page
8-36.) If the pedal height is incorrect, have a
Yamaha dealer adjust it.●Check the operation of the lever and pedal. They
should move smoothly and there should be a
firm feeling when the brakes are applied. If not,
have a Yamaha dealer check the brake system.
Brake fluid level
Check the brake fluid level. Add fluid if necessary.
(See page 8-33.)
Brake fluid leakage
Check to see if any brake fluid is leaking out of the
pipe joints or brake fluid reservoirs. Apply the
brakes firmly for one minute. If there is any leak-
age, have a Yamaha dealer check the brake sys-
tem.
Brake operation
Test the brakes at slow speed after starting out to
make sure they are working properly. If the brakes
do not provide proper braking performance, check
the brake pads for wear. (See page 8-32.) Specified brake fluid:
DOT 4
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6-1
6
EBU19881
OPERATION
EBU19901Read the Owner’s Manual carefully before riding
the ATV. If there is a control or function you do not
understand, ask your Yamaha dealer.
WARNING
EWB00631Read 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.EBU20184Starting a cold engine NOTICEECB00150See 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 key to “ON” and the engine stopswitch to “ ”. 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.
TIPThis 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:
Position (1):
Cold engine start with ambient temperature
below 5 °C (40 °F).
Position (2):
Cold engine start with ambient temperature
between 0 °C (30 °F) and 30 °C (90 °F).
Position (3):
Cold engine start with ambient temperature
above 25 °C (80 °F).
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6-2
6
Ambient temp./starter (choke) position
6. Completely close the throttle lever and start the engine by pushing the start switch.
TIPIf 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 energy. Do not
crank the engine more than 10 seconds on each
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.
8. Continue warming up the engine until it idles smoothly, then return the starter (choke) to
position (3) before riding.TIPThe engine is warm when it responds quickly to the
throttle with the starter (choke) turned off.NOTICEECB00163For maximum engine life, never accelerate
hard when the engine is cold!
1. Fully open
2. Half open
3. Closed
4. Starter (choke)
1 2 3
12
3
4
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6-3
6
EBU20291Starting 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.EBU20522Shifting 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, release the throttle lever, ap-
ply the clutch, and then repeatedly 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, and then re-
lease the clutch.
EBU20592To start out and accelerate1. Release the throttle lever, apply the front or rear brake, and then release the parking
brake.NOTICEECB00200Always close the throttle before shifting gears,
otherwise damage to the engine and drive train
may result.2. Pull the clutch lever to disengage the clutch.1. Shift pedal
2. Neutral position
1
2
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6-4
6
3. Shift into first gear, and then release the
brake.
4. Open the throttle gradually and at the same time, release the clutch lever slowly.
WARNING! Opening the throttle abruptly or releasing the clutch lever too quickly
could make the ATV wheelie, which would
increase the chance of an accident, includ-
ing an overturn.
[EWB00731]
5. Once the ATV has attained adequate speed, release the throttle, and at the same time,
quickly pull in the clutch lever.
6. Shift the transmission into second gear. (Make sure not to shift the transmission into
neutral.)
7. Open the throttle part way and gradually re- lease the clutch lever.
8. Follow the same procedure when shifting to the next higher gear.EBU20650To decelerate
When slowing down or stopping, release the throt-
tle and apply the brakes smoothly and evenly. As
you slow down, shift to a lower gear. Be sure that
the engine has sufficiently slowed before engaging a lower gear. Improper use of the brakes or shifting
can cause the tires to lose traction, reducing con-
trol and increasing the possibility of an accident.
WARNING
EWB00710Make sure the engine has sufficiently slowed
before shifting to a lower gear. Engaging a low-
er gear when the engine speed is too high
could make the wheels stop rotating and lose
traction. This could cause loss of control, an
accident and injury. It could also cause engine
or drive train damage.NOTICEECB00180●Even with the transmission in the neutral po-
sition, do not coast for long periods of time
with the engine off, and do not tow the ATV
for long distances. The transmission is prop-
erly lubricated only when the engine is run-
ning. Inadequate lubrication may damage
the transmission.
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