Sport Rider February 1995 "A look back at the quirky Turbo"

Magazine articles about the 750 turbo

Sport Rider February 1995 "A look back at the quirky Turbo"

Postby Dirck » Fri May 20, 2016 2:25 am

.
.................................................
http://www.sportrider.com/kawasaki-zx750-turbo

Image

Kawasaki GPz750 turbo
Editor's note: This article originally appeared in the February 1995 issue of Sport Rider.
In the early 1980s the editorial rumor mills worked overtime. Excited whispers were traded about a “new technology” that bikedom’s Big Four planned to introduce. All was veiled in secrecy, but alert people soon knew what the hubbub was about: turbochargers. Factory turbo bikes.
In 1978, Kawasaki arranged with American Turbo Pac—maker of small industrial turbochargers—to produce the insanely fast 1000cc Z1R/TC. When dragracer extraordinaire Jay Gleason lit up the track with a 10.05 quarter-mile, you’d better believe someone was listening. Ten-oh-five—on a seventies street bike, with skinny tires. Sixteen years later, even the brutal ZX-11 can manage only a wheezy 10.26-second elapsed time.
So the Japanese moved as one into the ’80s, brows equally moist with Turbo Fever. Yamaha, H*nda and Suzuki’s turbos were heavier and hardly any quicker than the normally aspirated bikes from which they came. The engines were small—500s or 650s. That, along with the weight and physical remoteness of the turbochargers from the engine, meant significant “spool-up” times, called turbo lag. Also, maximum boost pressures were in the seven-pound region—pretty low. After negative press coverage and the word from the grapevine, the buying public avoided the first three turbos.
Kawasaki’s version was christened the GPz Turbo and introduced as an early ’84 model. It was based on the GPz750, giving Kawasaki a good base to work from. Few changes were required for the Turbo model. It used flat rather than domed pistons; the mild cylinder head from the KZ650; large-diameter, thinner-walled frame tubing; a specially hardened primary chain; a thicker swingarm; different ignition curves and cam timing; and different Uni-Trac rear linkage. The Turbo also sported fuel injection rather than carburetors, along with a small microprocessor. The “DFI” (Digital Fuel Injection) computer used electronic sensors to automatically monitor and adjust for throttle position, altitude and other factors. Due to its full fairing and extra plumbing, the bike outweighed the standard 750 by some 30 pounds. But it also made an additional 35 horsepower.
When the ’83 bike was introduced at Austria’s famed Salzburg-ring circuit, it created an immediate sensation. Dubbed the ”GPz Turbo,“ the Kawasaki was over a second quicker than the other pressurized bikes. And with its Hitachi turbocharger sitting in front of the engine, connected by four short head pipes, boost lag times were reduced compared to the competition.
Again with “Pee Wee” Gleason on board, a preproduction version of the Kawasaki Turbo recorded a scalding 10.7 quarter-mile. Heck, even magazine staffers did 11.1s and twos. In its “Final Conflict” issue (July 1984), Motorcyclist magazine clocked a 150-mph top speed for the blown Kwakker. (By comparison, the same journal recently tested the 1994 GSXR750 and came up with 11.4 seconds and 153 mph.) Obviously, the Turbo remains a potent weapon.
Within months of the GPz Turbo’s introduction, Kawasaki outdid itself again with its brilliant 900 Ninja. It made more, and definitely more progressive, power through its wide rev band. And the Turbo, always a bit leaden in the handling department, looked elephantine when pitted against the first Ninja. Also, the 900 didn’t scare certain by-products out of you when goosed midcorner. Not so the Turbo. In short, the Ninja was far more of a complete package.
All right, what’s Kawasaki’s Turbo like to ride? Exciting, that’s what. No, you won’t flick through the chicanes like your buddies on their CBR900RRs and VFR750s (or old Norton Commandos, either); canyon carving isn’t the Turbo’s metier. Instead, it makes deliberate progress, as befits machines with nearly 60-inch wheelbases. Sweepers and straights are a different story. In this environment the ZX750 will hold its own, thank you. It is, after all, making 73 foot-pounds of torque at 6500 rpm. These are serious numbers. Turbo-heads don’t give a lick that preboost performance (under 3500) is, well, civilized (Okay, a little doggy). Two blinks of an eye later and those two little wheels are doing their stuff. By four grand you’re hearing their high-pitched whine, like a demented dentist’s drill, only probably faster. By 5000, even guys with skidpads on their knees had better be paying attention.
As an everyday mount, the GPz Turbo is surprisingly useful. The riding is a nice compromise, tending more toward a 1990s standard than a sport bike. The bar is higher even than a ZX-11’s—which already is a great day-long tourer. The seat, especially if fitted with high-grade latex, is fine. You can commute to work, pottering along at 50 if need be. Off-boost, it resembles a modern 550. With an educated right wrist, controllable boost in the midrange is possible. Moderation is the word, and it applies here, provided the addicting whoosh of acceleration is resisted a little. That’s the hard part with this bike: the attraction and—to some—the repelling nature of the Turbo. The transformation, as one mid-’80s reviewer put it, from “Mr. Milquetoast to Mr. Monster” in a couple of seconds.
The ZX750 has attained cult status, and along with the other factory turbos has grown very collectible. The Kawi was produced for only two years, and according to factory records a mere 3500 were sold in the U.S. Of these, says Chestnut (who’s monitored salvage-yard computers and other sources), barely 15 percent remain intact or running.
In the end, the Kawasaki Turbo, with its fuel injection and computer gizmos, was in some respects ahead of its time. All-out speed was the factory’s goal, and this it achieved. Maybe in other respects it missed the boat. Yet this machine, quirks and all, remains great fun—a true and worthy retro-bike.
User avatar
Dirck
Supporter
 
Posts: 5279
Joined: Sun Jan 12, 2003 5:00 pm

Return to In the press

Who is online

Users browsing this forum: No registered users and 1 guest