Revs from hell -- stuck throttle or bad mojo?

[AZRickD]

I was having a ball on my 2005 EC250 at this weekend's race. A 52 mile GP north of Tucson. Rocks and sand. Nothing particularly technical except for lots of ingress and egress from silty sand washes.

I was on my second of two laps with five mile to go when I exited some single track and came to a kinda fun, long, rocky jeep road with a modest incline. I was motoring up nicely when I noticed (the whole thing transpired over a period of about 4 seconds -- or less) my revs begin to build, slowly at first, then faster. Like a Cox model airplane that had just run out of fuel. Lean condition.

I was well aware that I hadn't changed throttle position and was wondering about a stuck throttle. But this "stuck throttle" resulted in more and more revs until it was screaming beyond the point that my front tire started to loft (pre-loop).

I _attempted_ to grab a fist full of clutch and brake but I kept moving as I tried to find the kill switch and lost some leverage on the clutch lever. Moments from disaster (heading to a rock pile), I decided to do a strategic dismount and fix things later. As I dropped the bike I slammed my pinky into a rock (broken finger, rock is doing well). The sweep and course worker heard my still screaming motor and rushed to my aid as I finally found the kill switch on my now looped and pointing-downward bike (musta looped it when I let go of the clutch).

I re-started it and it was still acting funny. I couldn't tell if my throttle was sticky or if my hand was numb. I rode it up to the top of the hill with it still acting strange. It was revving mid-high, but not like a banshee as before. The sweep told me to shut it down. He said he was going to find a short cut for me but I told him I'd finish. With no real solution in sight, I backed off the idle screw and re-started. It behaved normally but I doubt the idle screw had anything to do with it.

I rode at sub RickSpeed with no real problem accept for the double whoop section and some particularly rocky sections flexing my stiff-as-a-board pinky. I was spooked that I might tip in a wash and prang my finger but that didn't happen. I did get my pinky thwacked by three tree branches though. Glad I had big bark busters on.

Not sure what happened to my revs. Stuck throttle or stuck slide doesn't quite answer it since the revs slowly increased to the moon without any grip input from me. *New thought* I wonder -- maybe the float got stuck partially closed and caused the carb to go lean.

I'll be at the doc's tomorrow getting x-rayed and set.

Typing with one hand sucks.

Thoughts?

Rick