2004 YAMAHA YFM50S engine

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DESCRIPTION AND MACHINE
IDENTIFICATION
1. Seat 8. Rear brake lever
2. Front cover 9. Parking brake
3. Fuel cock 10. Neutral indicator light
4. Fuse 11. Front brake lever
5. Engine stop switch with 12. Throttle lever
cord (lanyard) 13. Main switch
6. Footrest 14. Fuel tank cap
7. Shift lever 15. Handlebar switches
NOTE:
The machine you have purchased may differ
slightly from those shown in the figures of this
manual.
1
2
6
89
0q
w e r t
3
5
6 74
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CONTROL FUNCTIONS
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Main switch
Functions of the respective switch positions are
as follows:
ON:
The engine can be started only at this position.
OFF:
All electrical circuits are switched off. The key
can be removed in this position.
OFF ON
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4-3
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Indicator lights
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Neutral indicator light “N”
This indicator light comes on when the transmis-
sion is in neutral.
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Handlebar switches
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Engine stop switch “ENG. STOP”
Make sure that the engine stop switch is in the
“RUN” position before starting the engine. The
engine stop switch controls ignition and can be
used at all times to stop the engine, especially in
an emergency. The engine will not start or run
when the engine stop switch is turned to “OFF”.
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1. Neutral indicator light “N”
1. Témoin de point mort “N”
1. Luz de control de punto muerto “N”
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1. Engine stop switch “ENG. STOP”
2. Start switch “START”
1. Coupe-circuit du moteur “ENG. STOP”
2. Contacteur du démarreur “START”
1. Interruptor de paro del motor “ENG. STOP”
2. Interruptor de arranque “START”
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Start switch “START”
The starter motor cranks the engine when this
switch is pushed.
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See starting instructions prior to starting
engine (see page 6-3 for details).
NOTE:
If the starter switch is pushed with the main
switch “ON” and the engine stop switch “OFF”,
the starter motor will be activated but the engine
will not start. To start the engine, be sure to
position the engine stop switch at “RUN”.
1
1. Start switch “START”
1. Contacteur du démarreur “START”
1. Interruptor de arranque “START”
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Engine stop switch with cord (lanyard)
The clip must be attached to the engine stop
switch for the engine to run.
The lanyard should be held by putting your fin-
gers in the loop as shown.
312
1
1. Engine stop switch 2. Clip
3. Lanyard
1. Coupe-circuit du moteur 2. Clip
3. Longe
1. Interruptor de parada del motor 2. Retenedor
3. Acollador
1. Lanyard
1. Longe1. Acollador
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4-9
Should the ATV be separated from the parent by
a distance longer than the lanyard length, the
lanyard will pull out the clip and stop the engine.
For further explanation of this switch and the
lanyard, see “TEACHING YOUR CHILD TO
OPERATE THE ATV” in the “SAFETY INFOR-
MATION” section.
NOTE:
8The engine cannot be started with the clip
removed.
8When your child has developed sufficient skill
to no longer need you to follow with the lan-
yard, the lanyard can be stowed under the
seat of the ATV. However, you must still
closely supervise your child at all times during
ATV operation.
1
1. Lanyard1. Longe1. Acollador
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Throttle 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.
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Malfunction 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.
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1. Throttle lever1. Levier d’accélérateur1. Palanca del aceleración
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Speed 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. Yamaha recommends that all
beginners start off with the speed limiter screw
turned in to limit the amount of speed available
while they learn. The limiter screw may be grad-
ually turned out to increase maximum speed as
the beginner becomes more familiar with operat-
ing the ATV.
12
a
1. Locknut 2. Adjuster a. 12 mm1. Contre-écrou 2. Dispositif de réglage1. Contratuerca 2. Ajustador
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