This happened years and years ago, probably 9 years. I used to ride BMX, skate park tricks and stuff. I removed the rear brakes on my bike to make it lighter, don't ask, that's just what we did back then. I decided to go for a jump I'd never done before and of course I stuffed it right up. I backed out just before I went up the jump and remembered I had no back brakes so I had no choice to go for it. My front wheel hit the coping (Lip of the downramp of the jump) and I went over the handlebars barreling down onto the concrete.