Kawasaki’s Z1-R TC was undoubtedly the fastest motorcycle you could buy in 1979
In the 1970s factory café racers were the preserve of Europeans. Norton had its 750 production racer, Ducati its 750 Sport and 750 and 900 Super Sport, Moto Guzzi its V7 Sport and 850 Le Mans, and BMW its R90S. But the European stranglehold was broken in 1977 when Kawasaki released its Z1-R.
With a fibreglass quarter fairing, smoked windscreen, low European handlebars, a 60-Watt quartz-halogen headlight and an instrument panel that included a fuel gauge and ampmeter, the Z1-R followed the style of BMW’s R90S but had what the BMW didn’t: 90hp and a quarter mile time of under 12 seconds.
The Z1-R was a ground-breaking design for a Japanese manufacturer, and it should have been a recipe for success but, unfortunately for Kawasaki, its Z1-R was produced a bit prematurely.
Beneath designer Kurashima’s angular styling was the same old-school Japanese chassis that could barely cope with the strain of the 1000cc DOHC engine.
Kawasaki beefed up the swingarm and fitted four sets of needle bearings in the pivot, but the mild-steel frame was essentially unchanged.
The braking was upgraded to twin drilled 296mm front discs with floating calipers, and a single 292mm drilled rear disc with a twin-piston caliper, while the front wheel was downsized to an 18-inch item to allow a wider 3.50-section tyre. But the main problem for the Z1-R was its timing. It arrived only months before a new wave of Japanese superbikes, notably Suzuki’s better-handling GS1000, faster Honda CBX1000 six and gruntier Yamaha XS1100. The first Z1-R was produced in metallic silver, accentuated by black highlighting on the engine and many other components.
It looked great, but no-one bought it.
This prompted Kawasaki in the US to seek a short-term solution to elevate the Z1-R back to the top of the performance heap. In 1978 it teamed with Californian firm Turbo Cycle Corporation (TCC) to produce a limited number of Z1-R turbos, or Z1-R TCs, fitted with American Turbo-Pak (ATP) compressor kits. No warranty on the turbocharged bikes were offered, and 250 TCs were initially produced in the original silver.
After managing to sell those first 250 bikes, TCC obtained a further 250 unsold 1978-spec Z1-Rs and transformed them into second-generation TCs for 1979.
Noted Californian customiser Molly Designs drew up a new colour scheme and graphics over the original paint, and Kawasaki advertised the TC as “the machine for the elite of motorcycling. It’s for those who like to be out in front.”
The ATP kit was basically bolt-on. Apart from the intake and exhaust system, the engine was stock, right down to the cast 8.7:1 pistons. TCC considered the engine more than strong enough to handle the increased power. The only concession made was the installation of baffle in the sump to prevent oil starvation during hard acceleration.
The turbine was a small Ray Jay, and induction was by a single 38mm Bendix float-type carburettor, mated to an ATP manifold. The manifold, carb, turbine/compressor and stumpy exhaust weighed slightly less than the stock four Mikuni carburettors and four-into-one exhaust.
A rectangular wastegate built into the exhaust header regulated boost and this was limited to a moderate 8psi to protect the engine.
A handlebar-mounted glycerine-filled pressure gauge showed just how much boost the engine was getting. The output was a conservative 135hp at the crankshaft, or 108hp at the rear wheel, and the top speed around 240km/h, depending on the boost and gearing. There was no doubt the Z1-R TC was the fastest motorcycle you could buy in 1979, even if the power was way too much for the stock chassis.
The Z1-R TC represented the end of the era of engines triumphing over chassis. Raw and brutal, it was a straight-line motorcycle and made no pretensions otherwise.
The TC was about making a statement. As the advertising material said, “It’s as subtle as pulling up next to a Volkswagen at a stop sign in a fire-breathing fuel dragster. It’s not for everyone, but everyone will know.”
Five Truths About Turbos
Although not strictly a production model, the Kawasaki Z1-R TC was the first turbocharged motorcycle you could walk into a showroom and buy – but only if you lived in the US. It was never officially imported into Australia, although three made it to New Zealand.
To advertise the TC’s performance, Turbo Cycle Corporation (TCC) had world-speed record holder Don Vesco ride one at the Bonneville Salt Flats at 260km/h.
TCC then put on a Goodyear slick, wheelie bar and rear struts, and gave it to ATP development rider Jay “Pee Wee” Gleason. In the modified street-drag class, Gleason went on to turn standing quarter-mile times of 10.03 seconds at 225km/h.
Turbocharging was fashionable in the early 1980s. Suzuki and Yamaha built turbocharged air-cooled 650cc fours, Kawasaki a 750 and Honda the CX500TC. Even Moto Morini developed a turbocharged prototype.
The turbo revolution was short. By 1984 there was no need for expensive, heavy and complex machinery that provided no performance advantage over conventional motorcycles.
What It’s Worth?
New (US) $5000
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Article by the guru Ian Falloon