I'm aware of two incidents involving biker gangs back in the early seventies in Louisville. I believe both groups involved were Outlaws MC. In the first incident, a drunken Outlaw was thrown out of a club called the Windmill. He and about 12 of his pals returned the next night and beat the hell out of everyone who happened to be in the bar. The other incident involved a fight that occurred at the Octoberfest, in which a drunken group of about two dozen Outlaws began a brawl in an open-air tent that left hundreds injured. In both cases, the Outlaws were armed with chains, tire-irons, and knives, and attacked mainly unarmed civilians who happened to have the bad luck to be in the same area with them. Maybe the Angels are different.
Funny thing, it took away a lot of the romantic concepts about biker clubs for me. They can keep the colors and the attitudes. I prefer the company of one or two friends and the open road.