Kawasaki GPz 750 Turbo

The Kawasaki GPz750 Turbo was a sportbike manufactured from 1983 to 1985.

Although carrying GPz badges on the engine covers, it was only referred to by Kawasaki as the "750 Turbo" - the GPz tag wasn't mentioned. Development started in January 1981 as a turbocharged 650, then as a 750 from November 1981. When finally released, the stock bike made a claimed 112 hp, had sports bike handling (for the day) and looked good - especially next to the other factory turbo bikes which were already on the market - the Suzuki XN85, Honda CX500 and CX650 turbos, and the Yamaha Seca Turbo. Performance was on a par with the GPz1100, at around 11.2 secs at 125 mph for the quarter mile and 148 mph flat out. One magazine even branded it the fastest bike they had ever tested, and Kawasaki ran some ads claiming it to be "The Fastest Production Motorcycle in the World". Jay "PeeWee" Gleason also recorded a 10.71 quarter for Kawasaki to show that the turbo had genuine performance and was ahead of the other factory turbos. It is widely considered to be the "best" factory turbo produced by the Japanese manufacturers.

It is widely perceived that the Kawasaki turbo was simply the addition of fuel injection and a turbocharger to a standard GPz750 motorcycle engine. This is far from the case, as almost every component was changed or strengthened for this bike and almost no major parts are interchangeable.

"Race Mode"

Another part of the mystique of this motorcycle is the hidden "race mode" inside the fuel computer. The bikes were factory restricted by means of an over boost cutout which operated at above 12 psi of turbo pressure. The computer can be switched back into "race mode" by a simple rearrangement of wiring to the fuel computer plug and this removes the 12 psi boost limit and allows a coarse adjustment of fuelling to suit higher flowing exhausts. This is borne up in some official Kawasaki documents reprinted at 750turbo.com detailing the fitment of an intake scoop and free flow exhaust along with the modification for racing use.

All 750 Turbo fuel computers support race mode, although its existence in US model computers has been denied (primarily it is alleged to avoid falling foul of EPA legislation), and it can be identified by the code "33" emitted from the computer diagnostic led on the front of the unit under the seat hump which is the only code that does not also light the DFI warning on the tank display.