 Also in June 1971, the first Ducati 750 GT models came out of the factory, distinguished by silver frames, metal-flake paint, fibreglass fuel tanks, 1 1/8" (1.125") Amal carburettors, and twin leading shoe rear brakes.At least one machine from this initial run is thought to have arrived at the US importer, Berliner - another early machine (possibly the test mule - complete with Dunstall dual front discs on gaitered Norton forks) was pictured much earlier, on Vic Camp's display at the 1970-71 winter UK national motorcycle show.Taglioni experimented with four valve heads at this time, but failed to produce better power figures than his two valve heads, so the two valve racers continued.