Given the serious looks on their faces, you’d think these men, clad in leather jackets, helmets, and boots, were vying for the national flat-track motorcycle championship. But, no, they were racing in the second-annual Mini-Bike Jamboree, which took place in the spring of 1961 at the Go Kart Raceway in Azusa, California. The minibike craze was big enough in the early ’60s that Car Craft magazine set aside four pages of its August 1961 issue to cover the Jamboree and its flat-track race, road race and scramble, “which took in much of the unimproved terrain surrounding the Azusa track.”
Azusa was home to Go Kart Manufacturing, one of the pioneering go-kart fabricators in the mid-’50s, and the race track was located at its facility. Minibikes were a natural offshoot of...