From Jesse James and Butch Cassidy to Scarface and Tony Soprano, outlaws have always held a singularly ambiguous place in America’s popular imagination: we fear and loathe the gangster’s appetite for violence; we envy and covet his radical freedom. In early 1965, LIFE photographer Bill Ray and writer Joe Bride spent several weeks with a gang that, to this day, serves as a living, brawling embodiment of our schizoid relationship with the rebel: Hells Angels.

Here, along with a gallery of remarkable photographs that were shot for LIFE but never ran in the magazine, Ray and Bride recall their days and nights spent with Buzzard, Hambone, Big D and other Angels (as well as their equally tough “old ladies”) at a time when the roar of Harleys and the sight of long-haired bikers was still new and — for the average, law-abiding citizen — utterly unfathomable. The day-to-day existence of these leather-clad hellions, after all, was as foreign to most of LIFE magazine’s millions of readers as the lives of, say, Borneo’s headhunters, or nomads of the Gobi Desert.