My 2010 550xp will not start once it gets hot. Bike will start great when it is cold (as it the engine hasn't ran in a while, or you can lay your hand on it). Once you run it for 20-30 minutes, it will just grunt when you hit the key. Took it back to dealer 5x, replaced battery several times, hooked jumper pack to it, and several other things. But nothing will help it, last thing the dealer did was they said the valves were out of adjustment bad, and it was ok for 30 or so miles, now back to the same thing. Its starting to aggravate me quite a bit now. Help would be great. Bike just acts like it is vapor locked after you get it good and hot.