It was called The King, and for years Kawasaki’s Z1 had no pretenders to its crown. With an electronically tested top speed of 134 mph in 1973, Kawasaki’s entry into the big four-cylinder bike market had an impact few have ever matched.
Its roots go back to 1967, when Kawasaki’s rapid two-strokes were frightening unwary riders with their wheel-standing habits and offending bureaucracy with their blue exhaust fumes. America was a vital market for the company, and was known to be planning legislation to control exhaust pollution, so engineer Gyoichi Inamura was appointed head of a team developing a new fourstroke model.
Their answer was a 750cc four cylinder, but Honda announced their own CB750 Four in 1968. The goalposts in the game of international success had been moved.
Kawasaki’s answer, codenamed T103, was running by 1970. By May 1972 production was under way and at the Cologne Show that September the Kawasaki Z1 was launched. It came with 82 HP @ 8.500 RPM, a top speed that made it the fastest production bike in the world, and it would purr through town at a whisper with no more than 83 decibels coming from the four upswept silencers.
Available in a combination of Candy Apple and Orange, the black cylinder block with the tips of its fins polished alloy highlights, a proud "900 Double Overhead Camshaft" badge on the sidepanels, it was a real stunner.
In Britain, it was yours for £1088, if you were lucky enough to afford the payments. Rich people could, while poorer but enthusiastic people said they would, whatever sacrifice they had to make. Some dug deeper for the optional second front disc, that didn’t become standard until the 1976 Model KZ900-A4.
It was not the best handling bike on the road, and when some magazine tester rode it through the speed trap at 134 mph it weaved and wobbled so much the timekeeper thought he was about to witness the fastest leg-off in the paper’s history. But the bike came back under control to an enthusiastic write-up. That year Motorcyclenews readers voted the Kawasaki Z1 MCN Motorcycle of the Year.
The engine became the definitive ‘bullet proof’ power unit. In 1973, at Daytona Speedway, Florida, a Kawasaki Z1 set a class world record of 150.8 mph (241 km/h) for ten kilometres and went on to average 109.6 mph for 24 Hours, another world record. Drag racers and sprinters, led by Holland’s importer Henk Vink, supercharged the Kawasaki Z1 900 engine to dominate their own sport. British chassis makers like the Rickman Brothers produced frames to tame the 82 bhp power and make it the fastest on straight roads or twisties.
The 903cc Z1 evolved, with minor modifications and colour and styling changes, from its 1973 form to the A4 version of 1976. The most obvious change in its successful life was a change to natural alloy cylinder finish on the 1974 Z10A version. For 1977 it was replaced by the Z1000, but the lean, mean Kawasaki Z1 is still remembered as the real thing. "The True King".
Kawasaki Z1 Specifications
Manufacturing : Kawasaki
Model : Z1 (Z1 900)
Production Year : 1972 - 1976
Engine : 4-Stroke, Air-Cooled, Inline 4 Cylinder DOHC 8 Valve
Bore x Stroke : 66 x 66 mm
Cylinder capacity : 903 cc
Fuel Supply System : Carburetor Mikuni VM 28mm
Compression ratio : 8.5: 1
Transmission : 5 - Speed
Ignition : CDI
Starter : Electric & Kick Starter
Max Power : 82 HP @ 8500 RPM
Max Torque : 73.5 N.m @ 7,000 RPM
Top Speed : 216 Km / h
Dimensions L x W x H : 2.200 x 685 x 1.170 mm
Wheelbase: 1.490 mm
Ground Clearance: 135 mm
Dry weight : 230 kg
Fuel tank capacity: 18 L
Frame : Tubular Steel Double Cradle
Front Suspension : Telescopic Fork 36 mm
Rear Suspension : Dual Shock, Adjustable
Front Brakes : Single Hydraulic disc 296mm, 2 Pots
Rear Brakes : Brake Drum (Drum) 7.9 Inches
Front Tires : 3:25 - 19
Rear tires : 4.00 - 18