" The Kawasaki Z1 was developed under the project name "New York Steak". In the late 1960s Kawasaki, already an established manufacturer of two-stroke motorcycles, had begun prototyping a 750 cc four-cylinder four-stroke sports motorcycle^[2] working with McFarlane Design in 1969 to develop the bike's overall appearance.^[12] When Honda introduced the CB750 to the market first, Kawasaki postponed the Z1's release until its displacement could be increased to 903 cc and the motorcycle could be marketed in the 1000cc-class.^[2]

Z1 production began in 1972 as the most powerful Japanese 4-cylinder 4-stroke ever marketed. In 1972 the Z1 set the world FIM and AMA record for 24-hour endurance. Beating the old record by 19.54 mph at Daytona for 2,631 miles with an average speed of 109.64 mph. Also at this time at Daytona a one-off Z1 ridden by Yvon Duhamel that was tuned by Yoshimura set a one lap record of 160.288 mph.

The Z1 featured full instrumentation and an electric start, produced 82 bhp and had a maximum speed of 130 mph to 132 mph(210 km/hr). It met with positive reviews from the motorcycle press, who praised its smoothness, damped vibration, easy starting (kick-start and electric were both available), straight-line stability and linear acceleration .