After a usual fall ride yesterday, I noticed a bit of milky colored goop leaking from the breather tube on my 07 YZ450. I did encounter a few puddles and mud holes along the trail ride and was thinking maybe this is all it was. After I got home and washed the bike and parked it in the garage this morning I noticed a quarter sized puddle of oil on the ground. I haven't changed oil yet, but it is due now after this ride. There were no problems after the two previous rides. Anyone have an idea on this. I forgot to mention I did clean air filter on the ride before this one. It just rained so not much dust so on Saturdays ride I just rode with the same filter. I didn't answer have this issue on the ride before. However I did top off the radiator before this last ride. Could it be coolant that boiled and mixed with crankcase gasses to form this milky goop? Edited October 18, 2011 by Stroker06 neglecting important info.