25 Years of GSX-Rs | Revolution

A quarter-century ago, Suzuki turned the sportbike world upside-down

By Aaron Frank, Photography by Kevin Wing

In the beginning there were sportbikes, and they were fast. Reagan-era sportbikes were also huge, ill-handling and, when pushed hard, just as likely to launch you skyward as rocket you forward. These mutant UJMs were crude appliances, producing great power but offering little control. Harnessing that power required major surgery: bracing the frame and replacing the suspension, wheels and braking systems wholesale. Wes Cooley’s #34 AMA Superbike had about as much in common with a Suzuki GS1000 as Travis Pastrana’s #99 NASCAR racer does with the Toyota you rented the last time you traveled.

Then Suzuki unleashed the 1985 GSX-R750, and everything we knew about sportbikes changed forever. Here was a production motorcycle that was virtually race-ready right off the showroom floor—the proverbial “racebike with lights.” Rather than follow the traditional design model and modify a streetbike for better on-track performance, GSX-R Lead Engineer Hiroshi Fujiwara flipped the program and took a highly specialized factory racing machine—Suzuki’s world championship-winning XR41 endurance racer (see sidebar, page 64)—and made the minimum modifications necessary for street use. “We had no competitors in the market,” Fujiwara said. “Our competition was factory racing machines.” Built with bona fide racing technology, the radical GSX-R750 was the first genuine racer replica, and the archetypal modern sportbike.

The original design brief was blunt: Build the fastest motorcycle in the world. But it wasn’t outright power Suzuki sought; it already had the sledgehammer-like GS1150E for that. GSX-R Project Leader Etsuo Yokouchi identified three distinct performance targets for the new machine: the highest top speed, the quickest acceleration and the lowest circuit lap time. The GSX-R750 would be comprehensively fast, and it would employ every trick Suzuki knew from racing: aero-dynamic bodywork, a compact, high-revving and powerful engine, and a light, stiff frame.

The all-new GSX-R had nothing in common with its pedestrian GS predecessors. Clip-on handlebars, rearset footpegs, foam-backed gauges and an externally vented fuel tank came directly from the race paddock. The trick, cast-and-extruded aluminum cradle frame—the first example of that technology on a modern production bike—was lifted from the XR41 endurance racer, along with the Full Floater monoshock rear suspension and sophisticated Positive Damping Fork. The full-coverage fairing concealed a massive oil cooler in its maw, hinting at the power within. Even the wheel size was race-inspired. Suzuki led the shift to quick-steering 16-inch front wheels on previous production bikes, but the GSX-R used 18-inch hoops, just like the factory endurance racers, to facilitate quicker brake and tire changes.

Motorcyclist staffer Jeff Karr’s report from the world press launch at Suzuki’s private Ryuyo test track in Hamamatsu, Japan, might seem hyperbolic in retrospect if it wasn’t spot-on. “This new Suzuki is not just an artful rehash of current streetbike technology, but a true milestone,” Karr crowed in our April ’85 issue. “Here is new technology that until now has been deemed too costly to apply to a streetbike. Here too are new ideas never before seen on any motorcycle. This Suzuki might turn out to be a new standard in overall performance.”

Many new ideas could be found inside the GSX-R’s unique, oil-cooled engine. Suzuki’s XN85 Turbo employed a cruder form of oil cooling two years earlier, but Engine Development Leader Yosunobo Fujii took that technology one step further and designed an innovative system using two separate oil pumps—one to lubricate the engine and another to route oil through a large cooler beneath the steering head and draw off excess heat. The oil-cooled engine made more power than an air-cooled equivalent, without adding as much weight as liquid cooling. Without water jackets surrounding each cylinder the engine was narrower and more compact, too.

Superlight engine internals and magnesium outer covers meant the short-stroke, 749cc engine weighed a whopping 29 lbs. less than the air-cooled GS750 engine, and produced a claimed 106 horsepower and 53.8 lb.-ft. of torque—roughly a 25 percent increase. That exotic alloy frame weighed just 18 lbs., or less than half as much as the GS’s steel affair. Actual curb weight for the complete bike was 464 lbs. on the Motorcyclist scales—featherweight compared to the 550-lb. Honda VF750F, 525-lb. Yamaha FZ750 and 530-lb. Kawasaki GPz750. This gave the first GSX-R an unbeatable power-to-weight ratio, putting Yokouchi’s trio of performance targets well within reach.

Karr’s riding impression wasn’t without criticism, however, as the radical GSX-R was far from perfect. Our tester noted how sensitive the bike was to rider inputs, especially at high speed, where he described the bike as “borderline twitchy.” Karr also critiqued the tendency to pitch excessively fore and aft, causing headshake under acceleration and weaving under heavy braking. The GSX-R took skill and a subtle touch to ride fast—but a capable rider could exploit the lightweight, hyper-responsive superbike like nothing else on the market.

Compliance with stricter emissions regulations, along with a stiff, 24.4 percent tariff on bikes over 750cc, delayed the GSX-R’s American introduction until ’86. The addition of a steering damper and a 1-inch-longer swing-arm calmed the handling enough to suitably impress the rest of the Motorcyclist staff in a March ’86 comparison. Testers effused over the Gixxer’s “ride on water” handling, even if they found the less-demanding Yamaha FZ750 ultimately the more agreeable bike.

Testers were less impressed with the GSX-R’s engine, especially compared side-by-side with Yamaha’s 20-valve torque pump. While in every other market the GSX-R was equipped with a rack of 29mm Mikuni flat-slide carburetors, the U.S.-spec engines used 31mm CV carbs, and suffered from a massive midrange flat spot that torpedoed rideability on the street. The peaky, top end-biased powerband demanded more frequent use of the close-ratio six-speed gearbox. Outright performance for the U.S.-spec machine suffered somewhat, too. Our example achieved only a 144-mph top speed—well short of the promised 150—and an impressive (but not definitive) 11.22-second, 120.5-mph quarter-mile.

Just as Karr predicted, however, the GSX-R set a new standard for sportbike performance and design. Soon all the competition—including Yamaha’s FZ, as well as Kawasaki’s ZX and Honda’s CB models—added an R suffix and adopted similarly uncompromising, racing-focused design strategies that persist to this day. For better or worse, the GSX-R brand has led the way for the last 25 years, pushing the performance envelope at every opportunity. A big-bore GSX-R1100 was introduced in ’86, followed by a baby brother GSX-R600 in ’92. The new millennium brought us the GSX-R1000—another iconic Suzuki that has had almost as great an impact on the sportbike world as the original GSX-R750. But even as the GSX-R lineup expands, contracts and changes over the years, the GSX-R750 remains the one constant. After rule changes favoring bigger bikes phased 750s out of racing, and every other manufacturer abandoned the three-quarter-liter displacement category, Suzuki’s GSX-R750 still soldiers on—filling an important niche for enthusiasts who demand a uniquely capable, all-around sportbike.

Unlike Kawasaki, which let its ZX-7R linger essentially unchanged for almost a decade before finally discontinuing it in ’03, Suzuki has continually updated and upgraded its signature GSX-R750 to ensure continued success. The model wandered off-line a bit in the ’90s, when it gained liquid cooling and a bad case of middle-aged bloat, but an extreme makeover for Y2K brought it back to the original, light-is-right design philosophy. The 2011 version—which marks the 25th anniversary of the GSX-R750 in America—is fully 20 lbs. lighter than last year, showing that Suzuki’s engineers remain as committed as ever to the lightweight performance ideal.

A line in our ’86 comparison suggested “Suzuki’s pursuit of minimum weight coupled with maximum sporting performance has put the motorcycle on the leading edge of the sporting class, perhaps too far out from the way most people actually use their sportbikes.” A quarter-century later, the current GSX-R750 exceeds the original by any objective measure, and most subjective measures, too. It’s 11 lbs. lighter, even with the added complexity of liquid cooling. It makes 20 percent more power at the same displacement, and thanks to the wonder of modern, dual-stage EFI, there’s no flat spot or peaky power delivery. Top speed is nearly 175 mph—equivalent to a race-kitted ’86 Superbike. And with the latest Showa suspension technology there’s no hint of high-speed instability, while low-speed maneuverability is flawless, too. The engine starts effortlessly—that old, carb-mounted choke will never be missed—shifts like whipped butter, demands little beyond regular oil/filter changes and is even reasonably comfortable. Not only does the modern GSX-R750 outperform the original in every way, it’s more accessible, too. Contrary to that original sentiment, even as the GSX-R750 becomes more potent at the racetrack, it becomes more docile as well. It has evolved closer to the way most people actually use their sportbikes.

Time marches on, and technology advances, but certain fundamental truths remain unchanged. One of those is that a properly engineered 750cc sportbike—one that combines the physical size of a 600 with the abundant power and rideability of a literbike—makes for the ultimate all-around sportbike. Doubt that argument? Hop on a Suzuki GSX-R750 of any vintage and prepare to have your mind changed. That fundamental rightness was evident in that very first example 25 years ago, and it remains unadulterated—enhanced, even—in the current generation. We can only imagine how the next quarter-century will improve what is one of our favorite sportbikes of all time.

  • «
  • |
  • 1
  • |
  • 2
  • |
  • 3
  • |
  • View Full Article
Enjoyed this Post? Subscribe to our RSS Feed, or use your favorite social media to recommend us to friends and colleagues!

*Please enter your username

*Please enter your password

*Please enter your comments
Not Registered?Signup Here
(1024 character limit)
  • Motorcyclist Online