Not a typo, it will start fine but won't stop. The motor in question is in my ATV. After my last run, I could not stop the motor. The kill switch didn't do it, I had to kill the fuel supply and cover the air intake and choke it out. The motor was revving at max RPM too. This is a simple two-stroke, no fancy electronics at work.
It might have something to do with hitting a tree at high speed. 
I am going to start repairing damage this weekend, but I wanted a list of things to look for that might be causing the engine issue. A ground wire popped off? Something lodged somewhere?
It's what's known as a "run-away". Usually due to an air leak which does two things, it leans out the mixture, which heats up the combustion chamber, and it inhibits throttle control (the wide open revving). The reason it wouldn't shut off is because the plug got hot enough to continue to ignite the now very lean mixture even though there was no spark. It's common when running 2stroke jet skis out of the water with no load on the engine.
Thanks. I hope to tear into it this weekend, now that I have all of the replacement parts gathered. Fingers crossed.
Replace all the top end gaskets, should be pretty cheap and not a hard job. I had the same thing happen to a Blaster I had although not as severe. Turned out to be the gasket at the base of the jug but I replaced them all to be safe.
... and stop hitting trees 
Pull the plug wire but use a stick! 
914Driver wrote:
Pull the plug wire but use a stick!
And not one thats still on a tree.
Yes, hitting a tree at high speed can cause all sorts of strange problems.
