2005 YAMAHA BIG BEAR PRO 400 maintenance

8-17 1. Engine oil filler cap
1. Bouchon de remplissage d’huile de moteur
1. Tapa del orificio de llenado de aceite de motor
1. Dipstick 2. Maximum level mark
3. Minimum level mark
1. Jauge 2. Repère de niveau maximum
3. Repère de niveau minimum
1. Varilla 2. Marca de nivel máximo
3. Marca de nivel minimo
EBU12334
Engine oil and oil filter element
The engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter element cleaned at the intervals speci-
fied in the periodic maintenance and lubrication
chart.
To check the engine oil level
1. Place the ATV on a level surface.
2. Warm up the engine for several minutes, and
then turn it off.
3. Wait a few minutes until the oil level settles
before checking.
4. Remove the engine oil filler cap, and then
wipe the dipstick off with a clean rag. Insert
the dipstick in the filler hole (without screwing
it in), and then remove it again to check the oil
level.NOTE:_ The oil level should be between the minimum and
maximum level marks. _
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8-51
9. Apply all-purpose grease to the air filter ele-
ment seat.
10. Install the air filter element on the frame.
11. Install the air filter element.
12. Install the air filter case cover by installing the
screws.
13. Install the seat.NOTE:_ The air filter element should be cleaned every 20–
40 hours. It should be cleaned and lubricated more
often if the machine is operated in extremely dusty
areas. Each time air filter element maintenance is
performed, check the air inlet to the air filter case
for obstructions. Check the air filter element rubber
joint to the carburetor and manifold fittings for an
airtight seal. Tighten all fittings securely to avoid
the possibility of unfiltered air entering the engine. _
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8-55
EBU00296
Carburetor adjustment
The carburetor is a vital part of the engine and re-
quires very sophisticated adjustment. Most adjust-
ing should be left to a Yamaha dealer who has the
professional knowledge and experience to do so.
However, the idling speed may be performed by
the owner as a part of the usual maintenance rou-
tine.CAUTION:
The carburetor was set at the Yamaha factory
after many tests. If the settings are disturbed
by someone without sufficient technical
knowledge, poor engine performance and
damage may result.
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8-67
EBU11860
Brake fluid replacement
Complete fluid replacement should be done only
by trained Yamaha service personnel. Have a
Yamaha dealer replace the following components
during periodic maintenance or when they are
damaged or leaking.

Replace the oil seals every two years.


Replace the brake hoses every four years.
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8-91
EBU00385
Battery maintenance
1. When the machine is not used for a month or
longer, remove the battery and store it in a
cool, dark place. Completely recharge the
battery before reinstallation.CAUTION:
A special battery charger (constant voltage/
ampere or constant voltage) is required for re-
charging a sealed-type battery. Using a con-
ventional battery charger may shorten the
battery life.2. Always make sure the connections are cor-
rect when putting the battery back in the ma-
chine.
U1C160.book Page 91 Wednesday, May 12, 2004 4:55 PM