Yamaha WR250F(N) Owner's Service Manual page 190

AIR FILTER CLEANING
5. Clean:
Air filter element
Clean them with solvent.
NOTE:
After cleaning, remove the remaining solvent
by squeezing the element.
CAUTION:
Do not twist the element when squeezing
the element.
Leaving too much of solvent in the ele-
ment may result in poor starting.
6. Inspect:
Air filter element
Damage
7. Apply:
Foam-air-filter oil or engine oil to the ele-
ment.
NOTE:
Squeeze out the excess oil. Element should
be wet but not dripping.
8. Install:
Air filter guide 1
NOTE:
Align the projection a on air filter guide with
the hole b in air filter element.
9. Apply:
Lithium soap base grease
On the matching surface a on air filter
element.
3 - 13
INSP
ADJ
Replace.