A couple of weeks ago I was cycling on a narrow, very rural road on southern Vancouver Island. There was no center line and I was within a foot of the right shoulder. Coming toward me were four motorcyclists. Two of them were side-by-side, approaching at a rate suggesting they were racing. Then the third motorcyclist pulled out from behind them, going even faster, to pass the other two. Because of how narrow the road was, this third motorcyclist was coming at me, at perhaps 140kph, in my lane. The passed me three abreast, and the idiot had at most a foot of clearance from me. Had I not maintained my line, it would have been curtains for me and a bad crash for him.
I have never seen a motorcyclists treat a cyclist with such irresponsibility. It definitely colored my attitude toward all of them, because that close call is what I think of whenever I see them.
(This came a few minutes after a jacked up pickup truck passed me from behind, then did the "rolling coal" thing. Obviously the intent was to make me go through a cloud of diesel smoke. I simply stopped and waited until the stuff dissipated, watching other motorists drive through it.)