A - arms

YFZ 450 oil mod

This is the point where you
want the added oiling to come from

First align the side case on your Mill making
 sure all gasket surfaces are clean.
Then Clamp the side case down to the bed
through one of the bearing holes
Next using a center finding tool align the
Mill head with the hole as pictured.
use a o-rind that is 7/16 3/8 by .068
using a 7/16 endmill drop the cut .040 deep
Next locate a .093 Drill bit
Using a hand drill, Drill
a hole as pictured below
next use a punch to make the
center of the oil filter housing
Finally clean and replace bearings
and assemble center cases