The motorcycling world gained by deletion when the second carburetor was removed from the Triumph Bonneville’s parallel-twin engine, creating the TR6 Trophy 650. Produced from 1956 to 1973, the TR6 series included TR6R Trophy street bike and TR6C Trophy competition models in the United States. The latter had high-rise pipes and knobby tires, and the look was irresistible. Both bikes were still muscular and evocative, but less aggressive responses made them just right for the boulevards while the competition bikes still begged to visit a track or trail.

The engine idled with a pleasant, fluttery burble before rising to a stirring growl under open throttle. Output was 45 horsepower at 6,500 rpm. For 1967, when Trophies accounted for about 30 percent of U.S. sales, an appealing Mist green and white paint scheme covered the tank, which had a 3.5-gallon capacity. The 1967 Triumph TR6R still wore the old-fashioned cargo rack, which emphasized its utility. Unlike the Bonneville, both TR6R Trophy roadster and TR6C Trophy street scrambler had an all-black seat rather than two-tone.

Changes to the Bonneville were also incorporated in the TR6 Trophy. For the engine, this meant new pistons and a revised oil pump. During the 1968 model year, the old Amal Monobloc carb bowed out in favor of an Amal Concentric. The motorcycling craze of the mid-1960s melded with the rising counterculture’s emphasis on individuality, and no bike fit between these two forces better than the TR6R and TR6C Trophies. If any further endorsement was needed, it came from popular culture, where everybody from Bob Dylan to Clint Eastwood rode Triumphs.