Oh no, I had a guy brought me his kx bottom end to rebuild. He was happy, and dropped off a xl-80 engine. He rebuilt it, and now it will not start. When it turned over it got tight, like something was out of time? Nope, the exhaust valve was bent, cheap and easy fix. NOOOOOOOOO, "I usually just straighten it back out in a vise, its just a dirt bike?" Wonder if he ever got that thing to run again? His phone number, do not answer that one again! You can lead a horse to water?