2003 YAMAHA BIG BEAR PRO 400 oil

8-35 1. Boot (× 2)
1. Soufflet (× 2)
1. Guardapolvo (× 2)
1. Boot (× 2)
1. Soufflet (× 2)
1. Guardapolvo (× 2)
6. Install the filler bolt and tighten it to specifica-
tion.
7. Check for oil leakage. If oil leakage is found,
check for the cause.
EBU00862
Axle boots
Check the protective boots for holes or tears. If any
damage is found, have them replaced by a
Yamaha dealer.Tightening torque:
Filler bolt (differential gear case):
23 Nm (2.3 m·kgf)
U4SH6A.book Page 35 Thursday, May 30, 2002 1:25 PM

8-45 1. Air filter element
1.Élément du filtre à air
1. Elemento filtrante
1. Element plate 2. Air filter element
3. Guide
1. Plaque d’élément 2.Élément du filtre à air
3. Guide
1. Placa del elemento 2. Elemento filtrante
3. Guía
3. Remove the air filter element, and separate it
from the guide.
4. Wash the element gently but thoroughly in
solvent.
WARNING
Always use parts cleaning solvent to clean the
air filter element. Never use low flash point sol-
vents or gasoline to clean the air filter element
because the engine could catch fire or ex-
plode.5. Squeeze the excess solvent out of the filter
and let it dry.CAUTION:
Do not twist the filter element when squeezing
it.6. Inspect the element. If damaged, replace it.
7. Apply SAE10W30 motor oil to the element.NOTE:The element should be wet but not dripping.
U4SH6A.book Page 45 Thursday, May 30, 2002 1:25 PM

8-59
3. Refill with the same type of brake fluid. Mixing
fluids may result in a harmful chemical reac-
tion and lead to poor brake performance.
4. Be careful that water does not enter the mas-
ter cylinder when refilling. Water will signifi-
cantly lower the boiling point of the fluid and
may result in vapor lock.
5. Brake fluid may deteriorate painted surfaces
or plastic parts. Always clean up spilled fluid
immediately.
6. Have a Yamaha dealer check the cause if the
brake fluid level goes down. Recommended brake fluid: DOT 4
U4SH6A.book Page 59 Thursday, May 30, 2002 1:25 PM

8-79
EBU00570
Cable inspection and lubrication
WARNING
Inspect cables frequently and replace if dam-
aged. Corrosion can result when the outer cov-
ering of control cables becomes damaged.
Cables can also become frayed or kinked. Op-
eration of controls could be restricted, which
could cause an accident or injury.Lubricate the inner cables and the cable ends. If
the cables do not operate smoothly, ask a Yamaha
dealer to replace them.
EBU00727
Brake and shift pedal/brake lever lubrication
Lubricate the pivoting parts of each lever and ped-
al.Recommended lubricant:
Engine oil
Recommended lubricant:
Lithium-soap-based grease
(all-purpose grease)
U4SH6A.book Page 79 Thursday, May 30, 2002 1:25 PM

8-85
WARNING
Battery electrolyte is poisonous and danger-
ous, causing severe burns, etc. It contains sul-
furic acid. Avoid contact with skin, eyes or
clothing.
Antidote:

EXTERNAL: Flush with water.


INTERNAL: Drink large quantities of water
or milk. Follow with milk of magnesia, beat-
en egg or vegetable oil. Call a physician
immediately.


EYES: Flush with water for 15 minutes and
get prompt medical attention.
Batteries produce explosive gases. Keep
sparks, flame, cigarettes or other sources of
ignition away. Ventilate when charging or us-
ing in an enclosed space. Always shield your
eyes when working near batteries.
KEEP OUT OF REACH OF CHILDREN.
U4SH6A.book Page 85 Thursday, May 30, 2002 1:25 PM

9-7
EBU00427
B. STORAGE
Long term storage (60 days or more) of your ma-
chine will require some preventive procedures to
guard against deterioration. After thoroughly
cleaning the machine, prepare for storage as fol-
lows:
1. Fill the fuel tank with fresh fuel and add fuel
stabilizer (if available).NOTE:Use of fuel stabilizer eliminates the need to drain
the fuel system. Consult a Yamaha dealer if the
fuel system is to be drained instead.2. Remove the spark plug, pour about one ta-
blespoon of SAE 10W30 or 20W40 motor oil
in the spark plug hole and reinstall the spark
plug. Ground the spark plug wire and turn the
engine over several times to coat the cylinder
wall with oil.
3. Lubricate all control cables.
4. Block up the frame to raise all wheels off the
ground.
U4SH6A.book Page 7 Thursday, May 30, 2002 1:25 PM

9-9
5. Tie a plastic bag over the exhaust pipe outlet
to prevent moisture from entering.
6. If storing in a humid or salt-air atmosphere,
coat all exposed metal surfaces with a light
film of oil. Do not apply oil to any rubber parts
or the seat cover.
7. Remove the battery and charge it. Store it in
a dry place and recharge it once a month. Do
not store the battery in an excessively warm
or cold place (less than 0°C or more than
30°C).NOTE:Make any necessary repairs before storing the
machine.
U4SH6A.book Page 9 Thursday, May 30, 2002 1:25 PM

10-1
EBU00428
1-SPECIFICATIONS
Model YFM400FP/YFM400FW
Dimensions:
Overall length 1,956 mm
Overall width 1,155 mm
Overall height 1,144 mm
Seat height 845 mm
Wheelbase 1,210 mm
Minimum ground clearance 215 mm
Minimum turning radius 3,500 mm
Basic weight:
With oil and full fuel tank 286 kg
Engine:
Engine type Air-cooled 4-stroke, SOHC
Cylinder arrangement Forward-inclined single cylinder
Displacement 386 cm
3
Bore
× stroke 83.0 ×
71.5 mm
Compression ratio 8.6:1
Starting system Electric and recoil starter
Lubrication system Wet sump
U4SH6A.book Page 1 Thursday, May 30, 2002 1:25 PM