A Corpsman buddy of mine once told me that during his tour of duty in Okinawa, they'd always be bringing in Marines who were racing about the gravel roads on motor bikes, wearing only shorts.
There got to be so many, he got ticked off at their stupidity and started giving 'em less and less pain killer before digging out the imbedded stones.
A fellow I know bragged about the pain he endured from a bike accident, which required more than 600 stitches. He then said he will continue to ride the same way. Although he seems reasonably intelligent otherwise (owns a successful business at 21), motorcycles do not contribute to his IQ.