Good day. I have a yamaha yz450f that i have bought 2 weeks ago. While i was riding i saw gas coming out of the breather tube. Can it be of the high compression of these 4 stroke machines or because of worn rings on the piston ? Will the bike not use oil when its rings are worn ? Because this bike is fantastic and still has a lot of power so must i be worried because of the gas that is coming out from the breather tube ? I also have a WR 450 '06 thats breather tube goes into the airbox but he doesnt breath as far as im concerned. Help me please i dont now if i must be worried or not.