Used to be big into it as a teen, then turned 16 and bought a Jeep.
Actually, it was a really bad crash when I was 15 that pretty much shook me up to the point of leaving it behind. Bit my tongue in half, knocked out some teeth, was knocked out cold for I don't even know how long - crashed during daylight and was awoken after dark by two people I didn't know who were able to help me get back to my campsite. I remember the moment before the crash, getting woken up, getting back to the campsite, and then nothing else until the next day. Put about a 5" crack in my helmet. I probably wouldn't be typing this if I hadn't been wearing it.