Cafe racers were part of the evolution of the factory sports bike. Before you could buy an off the peg "racer" you built your own, and a whole industry grew up supplying the parts, Dresda, Dunstall, Rickman etc. The first Jap cafe racer I saw was a cb750 with a Read Titan kit fitted, once the manufacturers saw there was money to be made they got in on the act and built their own, stifling individualism along the way.