:shocked:I've noticed that in very tight and slow woods sections that my wr450 seems to heat up a bit. I may have found an indirect cause to this problem, after laying the bike down a few times on the right hand side it looks like the exhaust pipe is very close to the water pump housing on the right hand side. I've loosend the header bolts on the head and adjusted the header pipe back up and away from the water pump housing. Maybe this will help. My pipe was bent down far enough to interfere with getting a T handle wrench on the upper oil filter cover bolt. I will try to keep you posted on the results.