I have to admitt, my dog likes to chase bikes... well, not just cycles but anything moving that has wheels, be it skateboards, wheelie-bins, scooters... I've always been concious of it and kept him under control, he's a big lad, 3 year old 12stone Rottweiler. He's gotten better and doesn't bother much now.
He did it in a nasty way, more of a playful thing.