Its a known issue with all CForce, UForce, and ZForce models.
Unfortunately, the factory has only come up with a final fix for the ATVs. There is no fix yet for the UTVs. I am supposed to be receiving 3 UTV kits at some point, but they aren't the final production fix-kit.
What I have been installing on my is an Air/Oil separator that HiSun uses on their 500 & 700 engines. It goes inbetween the crankcase and the air box. Basically you take the vent tube, cut it in half, and install this piece.