Originally Posted by rbabos
Well, what's kept me from one way valving the crankcase is an unknown in the design.
A quick search located a few threads where other forum members tried check valves to improve on the OEM crankcase vent system; e.g. this one
In this thread
an aftermarket oil catch can, check valves, and the MotoHooligan airbox are all discussed. (Ron, you posted in this thread).