My favourite Hells Angels story: they used to have a large chapter in Aldershot back in the 70's. Which was also the base for the British Army's elite Parachute Regiment. A group of Hell's Angels made the mistake of beating the shit out of a couple of Para's one night. The next day, over a hundred Paras rampaged through the city, beating every Hells Angel they could get their hands on to a pulp. Even worse, they destroyed the Angel's bikes.
After a few months of relentless attacks, the Angels closed up their Aldershot Chapter.