Yamaha RAPTOR YFM660R Owner's Manual page 304

1. Hose
1. Flexible
1. Manguera
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 the filter element mainte-
nance is performed, check the air inlet to the filter
case for obstructions. Check the air cleaner 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.
CAUTION:
Never operate the engine with the air filter ele-
ment removed. This will allow unfiltered air to
enter, causing rapid engine wear and possible
engine damage. Additionally, operation with-
out the filter element will affect carburetor jet-
ting with subsequent poor performance and
possible engine overheating.
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