Yamaha BIG BEAR 400 Owner's Manual page 127

7. Tap the element lightly to remove most of
the dust and dirt. Blow out the remaining
dirt with compressed air as shown. If the
air filter element is damaged, replace it.
NOTE:
_
Check the foam cover for damage and re-
place it if necessary.
_
8. Install the foam cover onto the air filter el-
ement.
9. Install the air filter element.
10. Install the air filter case cover by fasten-
ing the holders.
11. Install the seat.
NOTE:
_
The air filter element should be cleaned every
20–40 hours. It should be cleaned more often
if the ATV is operated in extremely dusty ar-
eas. Each time air filter element maintenance
is performed, check the air inlet to the air filter
case for obstructions. Check the air filter ele-
ment rubber joint to the carburetor and mani-
fold fittings for an airtight seal. Tighten all
fittings securely to avoid the possibility of unfil-
tered air entering the engine.
_
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