Brian Johnson from AC/DC drove a prototye in the Rolex 24 at Daytona last year and also races HSR all the time in his own car. Jason Priestley (90210) crashed an Indy car practicing for a race. Lorenzo Llamas used to race in IMSA as did Bruce Jenner back in the day. Those are all car guys though...
don't know he likes to go fast, but Ewan McGregor rode around the world on a Beemer. Surely, ya'll haven't forgotten "Long Way Round".
Forgot about McGregor and Richard Hammond - wrong side of the pond, I guess.... Now if I were a rich moviestar kinda guy that's how I'd spend my money.
and has a pretty sweet collection of vintage racing ferraris too. dont forget rowan atkinson. billy gray raced speedway for years. up til the mid 90s.
Tom Cruise has done some track days and taken a few schools. He has a few Ducatis as does prince William.
Don't forget Long Way Down too. I would suspect he's done some track riding at some point. What about these squids
has Travis Pastrana spent any time on a road racing bike? I consider him more of an athlete than a celebrity, but I'd love to see what he can do on a paved track with a 600.