I saw him jump 19 cars in 1968 at Lions International Dragstrip in Los Angeles and I'll never forget it. He didn't do it on a dirt bike, like they do it today. No, he did it on an old Triumph street bike. Back then the bikes were not that great, dirt or street. Before the jump, he spent several minutes warming up by doing, and showing off by doing wheelies in every way possible back then. I don't think the bikes were powerful enough to wheelie while sitting on the gas tank, because if they were, I'm sure he would have done it.
Like him or not, he was one crazy son of a bitch, and I bet he was fun to party with.