Back when car bumpers were metal, not paper thin plastic
One of the dimmer acquaintances of my youth heard the old story of the guy driving at night being pursued by mad chain swinging bikers. He discovers a chain lodged in his bumper with a severed finger. The acquaintance swallowed this and was reluctant to drive at night.

Cut to 10PM, he's driving and he's mobbed by couple of my pals riding Honda 250's. The chain that had been previously wedged in his rear bumper was dragging on the road. One of the bike's front wheel crossed the chain and skidded the bike resulting in an impressive case of road rash.
(the other guy not the one that gave you coochie warts, Fri 20 Jan 2017, 14:38, Reply)