1972 Kawasaki 900 super4 [Z1]1972 Kawasaki 900 super4 [Z1]

The Impact Created by the Ultimate Motorcycle

Around the world, the impact of the Z1 was felt not once, but twice. The first time was for its incredible performance. Riders around the world were intoxicated by the awesome power produced by its engine—the first In-Line Four in its class with DOHC, and displacing an unheard of 903 cm3.
The second time was for the Z1’s evocative styling. The development brief called for a design that was slim, sleek, and sexy. In other words, a 900cc-class bike that didn’t look or feel heavy, with a design that could slice through the air expressing its astonishing speed and performance. True to its name, the Z1 embodied the ultimate in performance and styling, firmly establishing Kawasaki’s reputation for building big, high-performance motorcycles.

陸空海とさまざまな分野陸空海とさまざまな分野

The Inside Story: Historical Influences

During the 125 years since the founding of the Kawasaki Group, Kawasaki used its technological prowess to establish itself in the aviation, marine and land-based transportation industries. In the early 1950s, the company’s aviation division leveraged its high level of technology to enter the field of motorcycle manufacturing. Some ten years later, they absorbed the Meguro Manufacturing Co., one of Japan’s oldest and most respected motorcycle manufacturers. In addition to everyday usability, Kawasaki developed motorcycles that were sportier and even more fun-to-ride.

The years passed, and in 1967, in strict secrecy, development began on a high-performance motorcycle the likes of which the world had never seen.

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The Inside Story: Z Development

During the 1960s and 70s, rapid motorisation and growing environmental concerns in the U.S. led to demands for four-stroke models with high-speed performance and lower environmental impact.
In response, Kawasaki began development of a high-performance 4-stroke model to replace the 2-stroke 500 Mach III, then the dominant machine in the high-performance motorcycle market. The development targets for the “ultimate” motorcycle that would become the Z1 were simple: performance and styling that surpassed the Mach III by far.
Spanning the Pacific Ocean, the development of the Z1 was a joint effort between Kawasaki engineers in the U.S. and in Japan. Engine development focused on high power output, but durability, ease of maintenance and environmental friendliness were also high priorities. A high-rigidity frame was designed to harness the massive power, and weight was pared wherever possible to ensure responsive handling.
The flowing lines of the tank, seat and tail cowl represent the distillation of hundreds of preliminary sketches.

The result was a motorcycle as powerful as it was beautiful, expressing in every detail the passion of its creators.

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The Inside Story: New York Steak is Served

Finally, in 1972, after five years of hard work, the Z1 was completed. The chief editors of America’s four leading motorcycle magazines were invited to the Kawasaki factory in Akashi, Japan for an exclusive press launch. They were astounded. His mind blown, the editor of Motorcyclist raved: “Kawasaki has redefined high performance.” The other magazines had similar high praise for the new Z1.
Propelled by the four articles, word of Z1 spread around the world, where it was received with great surprise and delight. During the initial press launch it came out that the Japan-U.S. development team had nicknamed the bike New York Steak—like the best meal on American menus, the Z1 would be the best bike they could build—and the pet name stuck.
The year after its release, the Z1 set the 24-hour world speed record at America’s Daytona Speedway, averaging 109.641 mph (176.4 km/h) for 2,631.402 miles (approximately 4,234.8 km), definitive proof of both its speed and reliability. This record was the first of many impressive records that Z models would set.

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