Kawasaki introduced the Z1 in 1973 as a return salvo to Honda, which had unleashed the CB750 and CR75 on the world a few years earlier. The two rivals are separated by Yamaha at the top of our rankings of the best motorcycle brands, based partly on the significance of their classic superbikes. The CB750’s four-stroke, four-cylinder engine displaced 736 cubic centimeters and produced as much as 67 horsepower, but Kawasaki surpassed those numbers with the Z1. It had a
