2005 YAMAHA BRUIN 350 engine

6-15
EBU02101
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.
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6-17
0–10 hours:
Avoid continuous operation above half throttle. Al-
low a cooling off period of five to ten minutes after
every hour of operation. Vary the speed of the ma-
chine from time to time. Do not operate it at one
set throttle position.
10–20 hours:
Avoid prolonged operation above 3/4 throttle. Rev
the machine freely but do not use full throttle at any
time.
After break-in:
Avoid prolonged full throttle operation. Vary
speeds occasionally.
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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6-19
EBU13760
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, place the machine transversely across
the incline, 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 easi-
ly. _1. Bring the machine to a stop by applying the
brakes.
2. Stop the engine.
3. With the rear brake lever and pedal applied,
apply the parking brake, and then slowly re-
lease 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 90 cc. Use by
children of ATVs that are not recommended for
their age can lead to severe injury or death of
the child. _
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7-17 1. Locknut 2. Adjusting screw
1. Contre-écrou 2. Vis de réglage
1. Contratuerca 2. Tornillo de ajuste
Speed limiter
For riders less experienced with this model, this
model is equipped with a speed limiter in the throt-
tle lever housing. The speed limiter keeps the
throttle from fully opening, even when the throttle
lever is pushed to the maximum. Turning the ad-
justing screw in limits the maximum engine power
available and decreases the maximum speed of
the ATV. Turning the screw in decreases top
speed and turning it out increases top speed.
Loading and accessories
Use extra caution when riding the ATV with addi-
tional loads, such as accessories or cargo. The
ATV’s handling may be adversely affected. Re-
duce your speed when adding additional loads.
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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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7-35
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, and turning tech-
niques in this area before trying more difficult ter-
rain. Always avoid riding on paved surfaces: the
ATV is designed for off-road use only, and han-
dling maneuvers are more difficult to perform on
pavement.
Set the parking brake and follow the instructions
on page 6-3 to start the engine. Once it has
warmed up you are ready to begin riding your
ATV. Remember that the engine and exhaust pipe
will be hot when riding and afterwards; do not al-
low skin or clothing to come in contact with these
components.
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7-37
With the engine idling, return the starter (choke) to
the closed position, shift the drive select lever into
the forward 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
until 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
possibility of an accident.
U5UH61.book Page 37 Tuesday, April 20, 2004 10:10 AM