The guy is just an idiot. The guy is on a sport bike, has no helmet, wears shorts, is shirtless, and wants to show off but he does not even know how to ride a bike. I think he is very lucky on this one.
Show offs and motorcycles just don't mix as you can see on these few other examples:
YouTube - Crashes - Motorcycle (funny)
YouTube - Crazy Idiot+Motorcycle=Crash
YouTube - Motorcycle Idiot
YouTube - Don't Be a Motorcycle 'Tard
YouTube - Why you shouldn't show off on your Harley Davidson.