Hey all, I have an 03 yz450f set for supermoto. At the last trackday I noticed a little cream coming out of the valve cover vent tube. Immediately thought I had water in the oil but upon checking the dipstick the oil was perfectly clean? I've heard from some that this is normal and others have told me that I have a base or head gasket leak, can anyone shed some light on this please? The bike was running great at a prior trackday except it was backfiring alot. Checked the pilot jet and found it was stock so put in a larger one to match the one over main jet and the duback pipe. The backfiring on decel is gone but then the bike didn't seem to have as much snap. I think it was due to the pilot being now too big since the dealer only had a 50 where stock is 42. I thought I should install a 45 or max 48 but since they were out I opted for the 50 just to see if the popping backfire would go away. It did but now I don't have as much snap. I'm hoping the loss of snap is from the pilot being too big and not from the cream indicating a bigger problem. what do you guys think?