2002 YAMAHA YFM80R engine

4-7
EBU00063Throttle lever
Once the engine is running, movement of the
throttle lever will increase the engine speed.
Regulate the speed of the machine by varying
the throttle position. Because the throttle is
spring-loaded, the machine will decelerate, and
the engine will return to an idle any time the
hand is removed from the throttle lever.
Before starting the engine, check the throttle to
be sure it is operating smoothly. Make sure it
returns to the idle position as soon as the lever
is released.wMalfunction of the throttle could make it diffi-
cult to speed up or slow down when you
need to. This could cause an accident.
Check the operation of the throttle lever
before you start the engine. If the throttle
does not work smoothly, check for the
cause. Correct the problem before riding the
ATV or consult a Yamaha dealer.
q
1. Throttle lever1. Levier d’accélérateur1. Palanca del aceleración
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4-9
EBU01051Speed limiter
The speed limiter keeps the throttle from fully
opening, even when the throttle lever is pushed
to the maximum. Screwing in the adjuster limits
the maximum engine power available and
decreases the maximum speed of the ATV.
Your ATV was delivered with an adjustable
speed limiter and also with an air intake restric-
tor plate. Yamaha recommends that all begin-
ners start off with the speed limiter screw turned
in and the air intake restrictor plate installed to
limit the amount of speed available while they
learn. The limiter screw may be gradually turned
out to increase maximum speed as the beginner
becomes more familiar with operating the ATV.
Parents should decide when to adjust the ATV
for more power as their youngster’s riding skills
improve. Once the ATV rider can operate with
skill at the top speed permitted by adjusting the
speed limiter alone, the air intake restrictor plate
can be removed.
q
w
a
1. Locknut 2. Adjuster a. 20 mm1. Contre-écrou 2. Dispositif de réglage1. Contratuerca 2. Ajustador
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Since removal of this plate will result in a signifi-
cant increase in power, turn the speed limiter
completely back in again; adjust it out in stages
as you did before.
Adjusting for maximum throttle lever movement
without removing the air intake restrictor plate
will cause the engine to run roughly at higher
speeds.
For air intake restrictor plate removal instruc-
tions, see page 8-33.wImproper adjustment of the speed limiter and
throttle could cause throttle cable damage or
improper throttle operation. You could lose
control, have an accident or be injured. Do
not turn the speed adjuster out more than 20
mm or the throttle cable could be damaged.
4-11
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4-17
EBU00075Parking brake
Use the parking brake when you have to start
the engine or park the machine, especially on a
slope. Apply the rear brake lever and push down
the lock plate to apply the parking brake.
Squeeze the rear brake lever to release the
parking brake.w8Always set the parking brake before start-
ing the engine. The ATV could start mov-
ing unexpectedly if the parking brake is
not applied. This could cause loss of con-
trol or a collision.
8Always be sure you have released the
parking brake before you begin to ride.
The brake could overheat if you ride the
ATV without releasing the parking brake.
You could lose braking performance
which could cause an accident. You could
also wear out the brakes prematurely.
q
1. Lock plate1. Plaque de verrouillage1. Placa de bloqueo
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4-19
EBU00083Shift pedal
This machine is equipped with a constant-mesh
3-speed transmission. The shift pedal is located
on the left side of the engine. Neutral is at the
bottom position.EBU00092Fuel tank cap
Remove the fuel tank cap by turning it counter-
clockwise.
q
3
2
1N
q
1. Shift pedal N. Neutral1. Pédale de sélection N. Point mort1. Pedal del cambio N. Punto muerto
1. Fuel tank cap1. Bouchon de réservoir de carburant1. Tapón del depósito de combustible
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4-21
EBU00093Fuel cock
The fuel cock supplies fuel from the fuel tank to
the carburetor.
The fuel cock has three positions.
OFF: With the lever in this position fuel will not
flow. Always turn the lever to this position
when the engine is not running.
ON: With the lever in this position, fuel flows
to the carburetor. Normal riding is done
with the lever in this position.
RES: This indicates reserve. If you run out of
fuel while riding, turn the lever to this
position. THEN FILL THE FUEL TANK
AT THE FIRST OPPORTUNITY. After
refuelling, return the fuel cock lever to the
“ON” position.
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4-23
EBU00096Choke lever
The choke is used to start a cold engine. Refer
to “Starting a cold engine” for proper operation.
(See page 6-3.)
q
w
ea
a. Choke lever 2. Half open (warming up position)
1. Fully open “ON” 3. Closed “OFF”a. Levier de choke 2. Mi-course (position de chauffe)1. Pleine course “ON” 3. Fermé “OFF”a. Palanca del starter
1. Abierto completamente “ON”
2. Semiabierto (posición de calentamiento)
3. Cerrado “OFF”
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5-1
EBU00113
PRE-OPERATION CHECKS
Before using this machine, check the following points:
ITEM ROUTINE PAGE
Brakes9Check operation, condition and free play.
5-5~ 5-7, 8-41 ~ 8-49
9Adjust if necessary.
Fuel9Check fuel level.
9Fill with fuel if necessary.5-9 ~ 5-11
Engine oil9Check oil level.
9Fill with oil if necessary.5-11 ~ 5-15, 8-13 ~ 8-17
Final gear oil9Check for leakage. 5-15, 8-19 ~ 8-21
Throttle9Check for proper throttle cable operation. 5-17
Wheels and tires9Check tire pressure, wear and damage. 5-19 ~ 5-25, 8-57
Fittings and fasteners9Check all fittings and fasteners. 5-17
Battery9Check fluid level.
5-17, 8-59 ~ 8-65
9Fill with distilled water if necessary.
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