light YAMAHA YFM50R 2007 Owners Manual

EBU17420
TABLE OF CONTENTS
SAFETY INFORMATION ............................. 1-1
LOCATION OF THE WARNING AND
SPECIFICATION LABELS ............................ 2-1
DESCRIPTION .............................................. 3-1
Left view ..................................................... 3-1
Right view................................................... 3-1
Controls and instruments ........................... 3-2
INSTRUMENT AND CONTROL
FUNCTIONS .................................................. 4-1
Main switch ............................................... 4-1
Indicator light ............................................. 4-1
Handlebar switches ................................... 4-2
Engine stop switch with lanyard ................ 4-2
Throttle lever ............................................. 4-4
Speed limiter ............................................. 4-5
Front brake lever ....................................... 4-6
Rear brake lever ........................................ 4-6
Parking brake ............................................ 4-6
Drive select lever ....................................... 4-7
Fuel tank cap ............................................. 4-7
Fuel ........................................................... 4-8
Fuel cock ................................................... 4-9Choke ...................................................... 4-10
Seat ......................................................... 4-11
PRE-OPERATION CHECKS ..........................5-1
Pre-operation check list ............................. 5-1
Fuel ............................................................ 5-3
Engine oil ................................................... 5-3
Final gear oil .............................................. 5-3
Front and rear brakes ................................ 5-3
Throttle lever .............................................. 5-4
Tires ........................................................... 5-4
Measuring the tire pressure ....................... 5-5
Tire wear limit ............................................ 5-6
Chassis fasteners ...................................... 5-6
Instruments, lights and switches ................ 5-6
Battery ....................................................... 5-6
OPERATION...................................................6-1
Starting a cold engine ................................ 6-1
Starting a warm engine .............................. 6-3
Shifting ....................................................... 6-3
Engine break-in .......................................... 6-5
Parking ....................................................... 6-5
Parking on a slope ..................................... 6-6
Accessories and loading ............................ 6-7

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ENGINE STOP SWITCH CORD
This model has an engine stop switch cord (lan-
yard) designed for use by an adult supervising the
child operating the ATV. When using the engine
stop switch cord, be sure the speed limiter on the
handlebar is adjusted to limit the ATV to a walking
speed. (See page 4-5.)
1. Push the clip on the end of the engine stop
switch cord under the engine shut-off switch
(black button).
2. Put your fingers in the loop at the other end of
the cord.
3. As your child is riding, walk behind the ATV,
closely watching his or her actions as well as
the path ahead.
4. If there is a potential hazard ahead or if your
child is not riding correctly, pull firmly on the
cord (lanyard) to stop the engine. Because the
ATV will continue to roll for some distance, al-
low extra time and distance to pull the cord be-
fore a potentially hazardous situation might be
encountered.
When your child has developed sufficient skill to no
longer need you to follow with the cord, the cord
can be stowed under the seat of the ATV. Howev-
er, you must still closely supervise your child at alltimes during ATV operation.NOTE:

The ATV will not start without the clip in place. Be
sure to remove the cord and store it in a safe place
to prevent operation of the ATV when you are not
around to supervise.WARNING
EWB00061

Always turn off the engine when refueling.

Do not refuel right after the engine has been
running and is still very hot.

Do not spill gasoline on the engine or ex-
haust pipe/muffler when refueling. Never re-
fuel while smoking, or in the vicinity of
sparks, open flames, or other sources of ig-
nition such as the pilot lights of water heat-
ers and clothes dryers. Gasoline can catch
fire and you could be burned.

When transporting the ATV in another vehi-
cle, be sure it is kept upright and that the fuel
cock is in the “OFF” position. Otherwise, fuel
may leak out of the carburetor or fuel tank.

Gasoline is poisonous. If you should swal-
low some gasoline or inhale a lot of gasoline
vapor, or get some gasoline in your eyes,

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Controls and instruments
NOTE:

The ATV you have purchased may differ slightly
from the figures shown in this manual.
1. Rear brake lever
2. Parking brake
3. Neutral indicator light
4. Front brake lever
5. Throttle lever
6. Main switch
7. Fuel tank cap
8. Handlebar switches
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765

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INSTRUMENT AND CONTROL FUNCTIONS
EBU17740
Main switch
The positions of the main switch are as follows:
ON
All electrical systems are supplied with power, and
the engine can be started. The key cannot be re-
moved.
OFF
All electrical systems are off. The key can be re-
moved.

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Indicator light
EBU17860
Neutral indicator light “”
This indicator light comes on when the transmis-
sion is in the neutral position.
1. Main switch
OFF ON
1

1. Neutral indicator light “N”
1

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Tire wear limit
Replace the tire when the tire groove decreases to
3 mm (0.12 in).
EBU19840
Chassis fasteners
Make sure that all nuts, bolts and screws are prop-
erly tightened.
EBU19850
Instruments, lights and switches
Check that all instruments, lights and switches are
working properly. Correct if necessary.
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Battery
Check the fluid level in the battery. Fill with distilled
water if necessary. (See page 8-25.) Recommended pressure:
Front
20.0 kPa (2.9 psi) (0.200 kgf/cm
2
)
Rear
20.0 kPa (2.9 psi) (0.200 kgf/cm
2
)
Minimum:
Front
17.0 kPa (2.5 psi) (0.170 kgf/cm
2
)
Rear
17.0 kPa (2.5 psi) (0.170 kgf/cm
2
)
Maximum:
Front
23.0 kPa (3.3 psi) (0.230 kgf/cm
2
)
Rear
23.0 kPa (3.3 psi) (0.230 kgf/cm
2
)
1. Tire wear limit

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OPERATION
EBU19900
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.
EBU20241
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 rear brake lever is applied with the drive se-
lect lever in the drive position. However, it is rec-
ommended to shift into neutral before starting
the engine.
5. Use the choke in reference to the figure:

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crank the engine more than 10 seconds on each
attempt.
7. If the engine is started with the choke in posi-
tion (1), the choke should be returned to posi-
tion (2) to warm up the engine. If the engine is
started with the choke in position (2), keep the
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 choke to position (3)
before riding.
NOTE:

The engine is warm when it responds normally to
the throttle with the choke turned off.
EBU20301
Starting a warm engine
Follow the same procedure as for starting a cold
engine, with the exception that the choke is not re-
quired when the engine is warm. Instead, start the
engine with the throttle slightly open.
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Shifting
This ATV has an automatic, centrifugal clutch.
To shift into the drive position, release the throttle
lever and apply the parking brake.
To shift into neutral, stop the ATV by releasing the
throttle lever and applying the brakes smoothly
and evenly.
EBU20630
To start out and accelerate
1. Release the throttle lever.
CAUTION:

ECB00210
Always close the throttle before shifting the
transmission into drive, otherwise damage to
the engine and drive train may result.
2. Apply the parking brake. (See page 6-5.)
3. Shift the transmission into drive.

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With the engine idling, shift the transmission into
the drive position and then release the parking
brake. Apply the throttle slowly and smoothly. The
centrifugal clutch will engage and you will start to
accelerate. If the throttle is applied too abruptly, the
front wheels may lift off the ground, resulting in a
loss of directional control. Avoid higher speeds un-
til you are thoroughly familiar with the operation of
your ATV.
When slowing down or stopping, release the throt-
tle and apply the brakes smoothly and evenly. Im-
proper use of the brakes can cause the tires to lose
traction, reducing control and increasing the possi-
bility of an accident.
TURNING YOUR ATV
To achieve maximum traction on unpaved surfac-
es, the two rear wheels are mounted solidly on one
axle and turn together at the same speed. There-
fore, unless the wheel on the inside of the turn is al-
lowed to slip or lose some traction, the ATV will
resist turning. A special turning technique must be
used to allow the ATV to make turns quickly and
easily. It is essential that this skill be learned first at
low speed.
WARNING
EWB01570
Always follow proper procedures for turning
as described in this Owner’s Manual. Practice
turning at low speeds before attempting to turn
at faster speeds. Do not turn at speeds too fast
for your skills or the conditions.
As you approach a curve, slow down and begin to
turn the handlebars in the desired direction. As you
do so, put your weight on the footboard to the out-
side of the turn (opposite your desired direction)
and lean your upper body into the turn. Use the
throttle to maintain an even speed through the
turn. This maneuver will let the wheel on the inside
of the turn slip slightly, allowing the ATV to make
the turn properly.

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CROSSING A SLOPE
Traversing a sloping surface on your ATV requires
you to properly position your weight to maintain
proper balance. Be sure that you have learned the
basic riding skills on flat ground before attempting
to cross a sloping surface. Avoid slopes with slip-
pery surfaces or rough terrain that may upset your
balance.
As you travel across a slope, lean your body in the
uphill direction. It may be necessary to correct the
steering when riding on loose surfaces by pointing
the front wheels slightly uphill. When riding onslopes, be sure not to make sharp turns either up
or down hill.
If your ATV does begin to tip over, gradually steer
in the downhill direction if there are no obstacles in
your path. As you regain proper balance, gradually
steer again in the direction you wish to travel.
WARNING
EWB01631
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 on
any 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.
OK

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EBU23211
Checking the spark plug
The spark plug is an important engine component,
which is easy to check. Since heat and deposits
will cause any spark plug to slowly erode, the spark
plug should be removed and checked in accor-
dance with the periodic maintenance and lubrica-
tion chart. In addition, the condition of the spark
plug can reveal the condition of the engine.
To remove the spark plug
1. Remove the spark plug cap.
2. Remove the spark plug as shown, with thespark plug wrench included in the owner’s tool
kit.
To check the spark plug
1. Check that the porcelain insulator around the
center electrode of the spark plug is a medi-
um-to-light tan (the ideal color when the ATV
is ridden normally).
NOTE:

If the spark plug shows a distinctly different color,
the engine could be operating improperly. Do not
attempt to diagnose such problems yourself. In-
stead, have a Yamaha dealer check the ATV.
1. Spark plug cap
1

1. Spark plug wrench
1