I was riding the other day and the quad was running just fine. I put it away and when I came out the next day to ride it wouldn't start. It was full of fresh gas, it was getting fuel, and was getting a great spark. It will turn over but wont fire. I tried compression starting it and still wouldn't fire. Is this a cause of my valves needing adjusting, or is there something else I can try?

Hey, I have the same trouble I will ride and after I shut it down and it cools off it would not start, this is the second time this happen to me. Then I adjust the valves chim it up and it starts right up and runs great.
Can any one tell why this happens. Thank you

I have the same prob. to i have stage 3 cams and a carb off a 07' rm 450 crd header and a hmf can,k&n filter i took it to the shop and the valves were way out of adjustment then after that it started up By it's self for once and it ran like a sculled ape then the next day i went to ride it and the P.O.S. would not start excuse my French there but i really don't want to take it to the shop every time i ride if you have any answer to this why all ltz 400's do this i would very much appreciate it