[techie610]

That doesnt make much sense to me.. EVERY gy6 I have done have the valves at .03IN and .04EX.
But, if it runs for 30 minutes, the dies?..
The valves effect it from the first stroke.
They would not just stop.
The ONLY thing I can think of is that they are made of cheap metal, that expands to much, when it gets that hot.
But I have NEVER heard of that happening.
If the problem raises again, please let us know. I am curious, and puzzled.