From the Library

[Biggles]

A few hundred motorcyclists got rowdy in Hollister on the July 4th, 1947 weekend. Townspeople admitted it had been no worse than what the cowboys did each year at the annual stock fair (and in fact the town staged motorcycle races in Hollister again just a few months later.)
A few days after the so-called riot, a photographer staged a photo of a beefy, threatening looking drunk, slumped on a motorcycle surrounded by empty beer cans.
Life Magazine ran it, triggering a media frenzy that lasted well into the 1960s. In a bizarre example of life imitating art, real gangs motorcycle outlaws were formed in response to those stories.
Bathroom Book Of Motorcycle Trivia  Mark Gardiner Day 62