Rode my YZ450F this past weekend and had a weird overheating problem. I was going pretty fast uphill in 5th gear then stopped at a road block and shut the bike off. About 5 minutes later I started riding again but was going slow in 2nd gear. The bike would die over and over again as I let out the clutch. Its an 06 and there is a vent tube that comes out of the top of the head that was spitting out white steam that smelt like burning coolant. Ended up walking the bike to make sure it didn't seize up on me. My buddy on his 05 cr450r was fine when he did the same thing as me (going fast then stopping). Any ideas whats wrong with the bike or why only my bike overheated this way?