1%er, from wikipedia-
"One Percenters
Members of motorcycle clubs are often viewed in a negative light by traditional society. This perception has been fueled by the movies, popular culture, and highly publicized incidents. One of the earliest and most notorious of these occurred in Hollister, California in 1947[14] [15] and is now dubbed the Hollister riot. Whether or not an actual riot occurred is debatable, but there was a motorcycle rally in Hollister from July 4 to July 6 of that year that was attended by about 4000 people. Several newspaper articles were written that, according to some attendees, sensationalized the event and Life magazine ran an article and a staged photograph of an intoxicated subject on a motorcycle parked in a bar. The film The Wild One, starring Marlon Brando, was inspired by the event, and it became the first in a series of movies that depicted bikers and members of motorcycle clubs in this stereotypical manner. The press asked the American Motorcyclist Association (AMA) to comment on the Hollister incident and their response[citation needed] was that 99% of motorcyclists were law-abiding citizens, and the last one percent were outlaws. Thus was born the term, "one percenter". They are also known as "Outlaw Motorcycle Gang" or (O.M.G.) according to the ATF.
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