2003 YAMAHA YFM660R engine

6-23
EBU00209
Engine break-in
There is never a more important period in the life of
your machine than the period between zero and
20 hours.
For this reason, we ask that you carefully read the
following material. Because the engine is brand
new, you must not put an excessive load on it for
the first several hours of running. During the first
20 hours, the various parts in the engine wear and
polish themselves to the correct operating clear-
ances.
During this period, prolonged full throttle operation
or any condition which might result in excessive
engine heating must be avoided. However, mo-
mentary (2–3 seconds maximum) full throttle oper-
ation under load does not harm the engine.
Each full throttle acceleration sequence should be
followed with a substantial rest period for the en-
gine by cruising at lower r/min so the engine can
rid itself of the temporary build up of heat.
If any abnormality is noticed during this period,
consult a Yamaha dealer.
U5LP62.book Page 23 Wednesday, May 8, 2002 11:24 AM

6-27 1. Button 2. Lock plate
1. Bouton 2. Verrou
1. Botón 2. Placa de bloqueo
1. Locked position
1. Position verrou bloqué
1. Posición bloqueada
EBU00211
Parking
When parking, stop the engine and shift into neu-
tral. Turn the fuel cock to “OFF” and apply the
parking brake.
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6-29
EBU01175
Parking on a slope
WARNING
_ Avoid parking on hills or other inclines. Park-
ing on a hill or other incline could cause the
ATV to roll out of control, increasing the
chance of an accident. If you must park on an
incline, put the machine in low gear, apply the
parking brake, and block the front and rear
wheels with rocks or other objects.
Do not park the ATV at all on hills that are so
steep you could not walk up them easily. _1. Bring the machine to a stop by applying the
brakes in low gear.
2. Stop the engine and release the clutch lever.
3. With the rear brake applied, apply the parking
brake and slowly release the brake pedal.
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7-7
Riding your ATV requires skills acquired
through practice over a period of time.
Take the time to learn the basic techniques well
before attempting more difficult maneuvers.
Not recommended for children under 16 years
of age.
WARNING
_ A child under 16 should never operate an ATV
with engine size greater than 90cc. Use by chil-
dren of ATVs that are not recommended for
their age can lead to severe injury or death of
the child. _
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7-25
Exhaust system
The exhaust system on the ATV is very hot during
and following operation. To prevent burns, avoid
touching the exhaust system. Park the ATV in a
place where pedestrians or children are not likely
to touch it. Dry grass or brush or other combustible
material accumulated around the engine area
could catch fire.
WARNING
_ Do not touch the hot exhaust system. Do not
park the ATV during or after operation in a
place where others might be likely to touch it.
Keep the engine area free of dry grass, brush,
or other combustible material. Do not operate,
idle, or park the ATV in dry grass or other dry
ground cover. _
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7-33
Select a large, flat area off-road to become familiar
with your ATV. Make sure that this area is free of
obstacles and other riders. You should practice
control of the throttle, brakes, shifting procedures,
and turning techniques in this area before trying
more difficult terrain. Always avoid riding on paved
surfaces: the ATV is designed for off-road use
only, and handling maneuvers are more difficult to
perform on pavement.
Set the parking brake and follow the instruction on
page 6-3 to start the engine. Once it has warmed
up you are ready to begin riding your ATV. As you
get on the ATV, be sure not to accidentally move
the shift pedal. Remember that the engine and ex-
haust pipe will be hot when riding and afterwards;
do not allow skin or clothing to come in contact
with these components.
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7-35
With the engine idling, pull the clutch lever to dis-
engage the clutch and shift into 1st gear, and then
release the parking brake. Open the throttle grad-
ually, and at the same time, release the clutch le-
ver slowly. Once the ATV has attained adequate
speed, release the throttle lever and at the same
time, quickly pull in the clutch lever and shift into
2nd gear. Open the throttle part way and gradually
release the clutch. Use this same procedure as
you move into the higher gears. Be sure to coordi-
nate the use of the throttle and shift pedal properly.
If the throttle is applied too abruptly or if the throttle
is not released during shifting, or if the shift pedal
is not released before applying the throttle, 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.
WARNING
_ Always open the throttle gradually and release
the clutch lever slowly. Otherwise, the ATV
could wheelie which would increase the
chance of an accident. _
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7-37
CAUTION:_ Do not shift gears without releasing the throt-
tle. Damage to the engine or drive train may oc-
cur. _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 shift-
ing can cause the tires to lose traction, reducing
control and increasing the possibility of an acci-
dent.
WARNING
_ Make 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 cause the wheels to stop rotating. _
U5LP62.book Page 37 Wednesday, May 8, 2002 11:24 AM