@Mara at least 2 ways:

* The bicyclist cycling on the footpath. I was once injured by one crashing into me from behind. He was going as fast as bikes could go. There was a bike lane but for some reason he wasn't using it.

* By not stopping on a red traffic light (or just not following the general traffic rules). My 4 year old came very close to being hit by a fast bike a few weeks ago, when we both were about to step on the street after the traffic light turned green for us (which meant they were definitely red for the bicyclist for a good 5s before that).