Honda CB750K
In June of 1968, Honda dropped the gauntlet that would forever change the world of motorcycling. The CB750 Four offered a combination of features never before seen on a single motorcycle. No longer would Honda be known as motorscooter company.
At the heart of the CB750 was an inline four-cylinder engine with a single overhead cam, four carburetors, four-into-four exhaust pipes. It produced 67 horsepower at 8000 rpm which was 15-percent more power than BSA's new 750 cc Rocket 3 even though they weighed about the same (just under 227 kg (500 pounds)). The Honda, obviously, was much faster.
It was not just the four-cylinder engine that caused such a stir; though most contemporary competitors had twin cylinders, fours had been offered by several manufacturers in the past. Rather, it was the fact that the four-cylinder power and smoothness was joined by a five-speed transmission, electric starter, a front disc brake, and a nearly bullet proof design—the first ever on a street bike—all at a reasonable price.
The single cam version was produced without much refinement until 1978 when it was replaced with a long awaited, more modern, double cam model.
In 1975 Honda introduced the "F" or "SuperSport" model which had a rear disc brake and a 4 into 1 header as well as some other cafe inspired additions. Later they brought out the "A" or "HondaMatic" model which was a clutchless 2-speed model with a wet sump lubrication system.
Honda also produced smaller fours in 350,400,550 and 650 displacements.
The first CB750s were produced with sand-cast cases that had a rough finish, later models had smoother castings. Those early sand-cast models have become the most valuable to collectors.
By 1970, Dick Mann had piloted a race-prepped CB750 into the winner's circle at Daytona and the world of aftermarket hop-up equipment came alive. The CB750 is also credited with casting the mold for what would later be called the "Universal Japanese Motorcycle," a breed of machines that would bring the motorcycle manufacturers of England to their collective knees.