This weekend in Prague at the FMX Gladiator Games, Chuck Carothers managed to take a Harley XR1200 motorcycle and pull off a back flip with it.  Being a street bike and not an off-road machine the impact was a bit too much to handle and sent him off the bike upon landing.  Regardless he took the bike which weighs about twice as much as a Motox bike and did a full back flip rotation to dirt with it. 

Just days before while practicing for this trick he managed to burn down Petr Pilat's foam pit and escaped from the flames before it burned to the ground.  Here is a video clip of his back flip on a Harley XR1200