2006-2009 Honda TRX250EX/TRX250X Service Manual, Page 221Get this manual
CRANKCASETRANSMISSION CRANKSHAFT
CRANKCASE ASSEMBLY
Clean the crankcase mating surfaces thoroughly, being careful not to damage themWash the strainer screen thoroughly in non-flammable or high flash poi nt solvent until all accumulated dirt has been removedBlow dry it with compressed airThe screen mesh should be examined closely for damage
Install the strainer plate and oil strainer with the thin edge of the strainer facing toward the front crank -