2003 YAMAHA BIG BEAR PRO 400 engine

5-19
EBU00152
Fittings and Fasteners
Always check the tightness of chassis fittings and
fasteners before a ride. Take the machine to a
Yamaha dealer or refer to the Service Manual for
correct tightening torque.
EBU00803
Lights
Check the headlight and tail/brake light to make
sure they are in working condition. Repair as nec-
essary for proper operation.
EBU00912
Switches
Check the operation of the light switch, engine
stop switch and any other switches. Repair as nec-
essary for proper operation.
EE.book Page 19 Monday, June 18, 2001 10:18 AM

6-3
EBU00505
Starting a cold engine
WARNING
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.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 “”.
4. Shift the transmission into neutral.
EE.book Page 3 Monday, June 18, 2001 10:18 AM

6-5 a. Starter (choke) lever
1. Fully-open
2. Half open
3. Closed
a. Starter (enrichisseur)
1. Complètement ouvert
2. Mi-ouvert
3. Fermé
a. Palanca del estárter (estrangulador)
1. Abre completamente
2. Semiabierto
3. Cerrado
NOTE:

When the transmission is in neutral, the neu-
tral indicator light should come on. If the light
does not come on, ask a Yamaha dealer to in-
spect it.


The engine can be started with the transmis-
sion and drive select lever in any position if the
rear brake lever is applied. However, it is rec-
ommended to shift into neutral before starting
the engine.
5. Use the starter (choke) in reference to the fig-
ure:
Position
1: Cold engine start-
ambient temperature below 5°C.
Position
2: Cold engine start-
ambient temperature at 0°C ~ 30°C
and warming up position.
Position
3: Cold engine start-
ambient temperature above 25°C
and warm engine start position.
6. Completely close the throttle lever and start
the engine by pushing the start switch.
EE.book Page 5 Monday, June 18, 2001 10:18 AM

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.
EE.book Page 7 Monday, June 18, 2001 10:18 AM

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.
EE.book Page 9 Monday, June 18, 2001 10:18 AM

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.
EE.book Page 17 Monday, June 18, 2001 10:18 AM

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.
EE.book Page 19 Monday, June 18, 2001 10:18 AM

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.
EE.book Page 21 Monday, June 18, 2001 10:18 AM