had something close to that hapen to me once i had a 1980 cr250 elsinor bored over 30 boysen reeds whit bro exaust and a bunch of other stuff bike was fast as hell i was racing the neibor down a stretch of power lines i had him by a go 50+feet in 3rd when all of the sudden im going asshole over elbos still not sure what happend to make me eat it but my left leg got caught between the rear fender and tire with the throtle stuck bent my handel bars tore my jeans off and i spent 2 hrs pulling dirt and tire tread out of my iner thigh but i won the race and shut him up about how fast he thought his bike was