Technically, ALL of them will die over time....

/stats geek

Oh, you mean die on the motorcycle. Well, possibly, but that doesn't mean that motorcycle riding is deadly dangerous in and of itself. It could be that certain individuals have tendencies to behave in risky ways, and they just happen to be doing so on a motorcycle. Take the bike away, and it's entirely possible those people will do something else (say canoeing or rock climbing, to name two random examples) in a risky manner and thus die. There are safe (or safER anyway) and unsafe ways to do just about anything you cna think of, so we all have to pick our odds.