2004 YAMAHA BIG BEAR PRO 400 engine

6-7
NOTE:

If the engine fails to start, release the start
switch, then push the start switch again.
Pause a few seconds before the next attempt.
Each cranking should be as short as possible
to preserve battery energy. Do not crank the
engine more than 10 seconds on each at-
tempt.


If the battery is discharged, pull the recoil
starter to start the engine.
7. If the engine is started with the starter (choke)
in position
1, the starter (choke) should be
returned to position
2 to warm up the engine.
If the engine is started with the starter (choke)
in position
2, keep the starter (choke) in this
position to warm up the engine.
8. Continue warming up the engine until it idles
smoothly and return the starter (choke) to po-
sition
3 before riding.CAUTION:
See the “Engine break-in” section prior to op-
erating engine for the first time.
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6-9
EBU00180
Starting a warm engine
To start a warm engine, refer to the “Starting a cold
engine” section. The starter (choke) should not be
used. The throttle should be opened slightly.
EBU00182
Warming up
To get maximum engine life, always warm up the
engine before starting off. Never accelerate hard
with a cold engine! To see whether or not the en-
gine is warm, check if it responds to the throttle
normally with the starter (choke) turned off.
U4SH6B.book Page 9 Tuesday, May 27, 2003 4:39 PM

6-17 1. Shift pedal N. Neutral position
1. Pédale de sélection N. Point mort
1. Pedal del cambio N. Posición de punto muerto
EBU00202
Shifting
This model is equipped with a dual, 5-speed for-
ward and 1-speed reverse transmission with a
centrifugal clutch. The transmission allows you to
control the amount of power you have available at
a given speed or for starting, accelerating, climb-
ing hills, reverse, etc. To shift into neutral, return
the throttle lever to its original position and repeat-
edly depress the shift pedal until it stops.CAUTION:
Do not coast for long periods with the engine
off, and do not tow the machine a long dis-
tance. Even in neutral position, the transmis-
sion is only properly lubricated when the
engine is running. Inadequate lubrication may
cause damage.
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6-19
EBU00650
To start out and accelerate:
1. Release the throttle lever.CAUTION:
Always close the throttle while shifting gears.
Otherwise, damage to the engine and drive
train may result.2. Shift into first gear and release the shift ped-
al.
3. Open the throttle gradually.
4. Once the machine has attained adequate
speed, release the throttle lever.
5. Shift into second gear and release the shift
pedal.
6. Open the throttle gradually.
7. Follow the same procedure when shifting to
the next higher gear.
WARNING
Always open the throttle gradually. Opening
the throttle abruptly would increase the
chance of an accident. It could make the ma-
chine wheelie or overturn.
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6-21
EBU00208
To decelerate:
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 make the wheels stop rotating. This
could cause loss of control, an accident and
injury. It could also cause engine or drive train
damage.
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6-23
EBU02092
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 fol-
lowed with a substantial rest period for the engine
by cruising at lower r/min so the engine can rid it-
self of the temporary build up of heat.
If any abnormality is noticed during this period,
consult a Yamaha dealer.
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6-27
EBU00211
Parking
When parking, stop the engine and shift into neu-
tral. Turn the fuel cock to “OFF” and apply the
parking brake.
EBU02201
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 ATV in low gear, apply the park-
ing 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 ATV to a stop by applying the
brakes in low gear.
2. Stop the engine.
3. With the rear brake lever and brake pedal ap-
plied, apply the parking brake and slowly re-
lease the brake pedal.
U4SH6B.book Page 27 Tuesday, May 27, 2003 4:39 PM

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. _
U4SH6B.book Page 7 Tuesday, May 27, 2003 4:39 PM