Returning With A Vengeance: Suzuki GSX-R750 Road Test

It's been a foregone conclusion that Suzuki has pretty much owned the 750 sportbike class since the last generation GSX-R750's debut in 1996. In one deft engineering move, Suzuki left the competition so far behind that the other two manufacturers offering 750 sportbikes quickly dropped their factory supported 750 Supersport teams from the AMA National series after the first season in which the new Suzukis ran. Its incredible performance topped the best the sportbike world had to offer--garnering two consecutive Sport Rider Bike of the Year titles in '96 and '97.

But lately things have been getting a little tougher for the GSX-R750. The competition on the street has ratcheted up several notches, with a few bikes (most notably those pesky R-series Yamahas) displacing the Suzuki as top dog in the sportbike world. And the latest 600s have been creeping up on the GSX-R in 750 Supersport class racing, even though the 600s are shackled with a weight handicap. Some pundits were even predicting the demise of the 750 category--with each passing year, 600s were getting quicker, and open-classers were getting lighter and smaller.

Well, all it will take is one ride on the new 2000 Suzuki GSX-R750 to send the message loud and clear: Don't even think about writing off the 750 class just yet.

Put succinctly, if you thought the last generation GSX-R750 was a ripper, the new Suzuki will simply knock your socks off. We are dead-serious about this. The latest supersport weapon from Hamamatsu has not only raised the 750-class performance bar much higher, but also is threatening to tread upon CBR929RR/YZF-R1/ZX-9R turf. And that's saying a lot for a motorcycle that has already moved the three-quarter-liter performance boundaries far beyond previous expectations.When pre-release reports of the new GSX-R's weight and horsepower specs began trickling in, we found them hard to believe. How could Suzuki engineers possibly trim nearly 30 pounds from a motorcycle that was already the model of compact and efficient design? And how could they do this while extracting even more power at the same time?

Much of the overall weight reduction came from the redesigned motor, which scales in more than 11 pounds lighter than the '99 version. Although the basic configuration remains the same, every possible component was shortened, lightened or redesigned altogether to make the GSX-R engine even more compact.Fanatical attention to design efficiency resulted in revamped engine components that not only increase power output, but also remain smaller and lighter. For instance, although the more compact, higher compression ratio (12.0:1 vs. 11.8:1) combustion chamber and straighter intake ports are made possible by the narrower included valve angle (25 degrees vs. 29 degrees), this normally results in a taller cylinder head. Yet by carefully reviewing the interior design layout, Suzuki engineers were able to keep the overall cylinder head height the same--while shortening it 9.5mm and simultaneously shedding 500 grams.

Well, sure, the dash looks pretty spartan, but Suzuki wanted only the absolute essentials on board--we now prefer the digital speedometer. The windscreen still provides good protection; note that the fork tubes are closer together.

Similar redesigns resulted in what may seem like infinitesimal weight reductions by themselves, but as a whole add up to major gains (remember that many of these lighter parts are reciprocating engine weight, translating to quicker revs and acceleration). Just a few of the many savings: valve train, 260 grams; camshafts, 200 grams (utilizing a cast iron alloy to allow a thinner construction); pistons and pins, 80 grams (forged instead of cast pistons, tapered pins); rods, 180 grams (shot-peening permits thinner design); crankshaft, 150 grams; air injection system, 700 grams (integrated design eliminates external hoses); crankcase castings, 690 grams--the list goes on and on.The Suzuki's chassis received just as much detailed attention to component shrinkage/dieting, and like the engine, the performance benefits aren't limited to less mass. Downsizing the primary frame spars not only allowed Suzuki engineers to cut weight, but also by moving the engine forward, placed more weight on the front wheel, and permitted a longer swingarm for better suspension control and rear tire traction. The primary frame section is 2 kilograms lighter than last year--with the swingarm shedding 800 grams compared to last year, even though it is 20mm longer.

Extensive R&D was conducted on the GSX-R's ram-air induction system, resulting in these repositioned/reshaped induction nacelles. The redesigned dual-bulb headlight works well.

Virtually every part on this motorcycle underwent some sort of weight loss program. Both the front fork and rear shock are shorter overall (plus a narrower fork pitch for better aerodynamics, and the shock body is now aluminum) for reduced weight, and lighter four-piston front brake calipers replace the six-piston units of last year. Brake discs, brake pedal, engine mounts, footpegs and wheels (the rear shrinks to a 5.50-incher) are lighter, thinner bodywork--everything had some weight shaved in one way or another. The end result? The new GSX-R scales in at 426 pounds wet; 27 pounds less than the previous model.

Working in tandem with the weight reductions are various subtle engine tweaks aimed at increasing the GSX-R's already class-leading horsepower. Besides the aforementioned higher compression ratio and straighter intake ports afforded by the shallower valve angle and consequent more compact combustion chamber, cam timing was modified to take advantage of the increased rpm range (redline sits at a stratospheric 14,000 rpm) made available by the lighter engine internals. Exhaust tuning was also slightly altered to match the improved breathing efficiency.

Even though the swingarm is 20mm longer, it is 800 grams lighter than last year. Note the new sprocket and carrier, which dropped 1000 grams; the rear brake caliper uses aluminum pistons and different pads, dropping another 101 grams.

Taking center stage on the engine changes, however, is the new fuel-injection system that utilizes servo-controlled secondary throttle plates positioned above the throttle-actuated units. Controlled by a new 16-bit CPU and working similar in concept to a CV carb slide, the secondary plates maintain intake velocity when the primary throttle is opened in order to smooth out throttle response. The throttle bodies have shrunk to 42mm (from 46mm), but the bores are tapered--which helps maintain intake velocity for better midrange power.

And it's the new EFI's response that you notice right off the bat on the street. Cold morning warm-ups are just as quick as before, but the moment you take off from a stoplight, the new GSX-R's vastly improved low-to-midrange acceleration comes to the fore. Compared to the previous EFI model, the new 750 literally leaps off the line without much prodding, and almost requires a bit of restraint to keep from appearing as if you're treating every stoplight like a dragrace. And while the GSX-R's lower midrange power won't embarrass an open-class or V-twin sportbike, its acceleration is quick enough above 5000 rpm that you won't need to flick a few downshifts in order to shoot the gap between wayward four-wheelers. Helping in this regard are the slightly revised gearbox ratios, which are all lower than last year's model.

The Gixxer's somewhat excessive driveline lash remains, however. Sloppy shifting through the first few gears can result in a jerky ride, but concentrating on smooth throttle transition eases this problem. Even under a heavy throttle hand, gas mileage remained the same as last year, with the blinking fuel light coming on around 165 miles to tell you the bike has approximately 30 miles left.There were no changes to the Suzuki's ergonomics, so its highway manners remain fairly status quo. While obviously not a sport-tourer, the GSX-R's riding position isn't overly radical; the reach to the bars is fairly short, the seat foam seems softer than last year's model, and unless you're much over six feet tall, your legs won't be pretzeled by the slightly rearset pegs. The bike's four-cylinder powerplant remains silky-smooth at nearly all rpms, keeping the decent rearward images from the mirrors somewhat fuzz-free. And despite the new fairing's more radically-canted windscreen, wind protection is still good.

Of course, once you hit a twisty road, ergonomics, schnergonomics--who cares? Riding the GSX-R750 in its true element makes you realize just why Suzuki engineers went through all that trouble to shed those pounds--indeed light does make right.

The new GSX-R750's innovative fuel injection uses a set of servo-controlled throttle plates above the rider-actuated plates to maintain intake velocity--similar to how a CV carb works. The old model's abrupt throttle response is mostly gone.

The new GSX-R possesses that rare balance of agility and stability that many sportbikes come close to attaining, but never quite achieve. Dropping a substantial amount of weight from the bike has made it flickable without resorting to radical steering geometry figures. Even though the rake/trail numbers are the same at 24 degrees/96mm and the wheelbase has grown by 20mm, the new GSX-R's turn-in effort is much easier without being overly twitchy. Steering manners are sharp and precise, and the stock steering damper mounted below the lower triple clamp feels less stiff than previous years.

Suspension rates in the fork have been altered to work with the changes in weight and chassis configuration, and both ends seem to be pretty close to spot-on. The lighter brakes, sprocket assemblies, wheels, etc., have permitted softer damping rates to allow some compliance without sacrificing chassis control when the pace picks up. High-speed compression damping seems to have been relaxed also, as the big bumps don't transfer as much shock back through the chassis like in past models. Front end feedback is excellent, making for high corner entrance and midcorner speeds. And ground clearance is abundant, canceling any worries of dragging hard parts getting in the way.

The 43mm inverted fork is 500 grams lighter, while the new four-piston calipers drop another 640 grams, and the 320mm brake discs lose 28 grams. The front wheel is 350 grams lighter than last year, while the rear is 200 grams less.

But couple this lighter and better chassis with a screaming motor that cranks out 123.0 horsepower at 12,500 rpm, and you've got the ingredients for one of the most exciting motorcycles to ride since Yamaha's R6. There's plenty of good acceleration available from 8000 to 10,000 rpm, if you desire to move along at a decent clip without undue haste; one could ride around at that rpm all day and be satisfied with the bike's performance. There is a sense of urgency, however, as the revs start to pick up quickly in that range--almost as if something is about to be unleashed.

Once the revs get above that five-figure mark, though, the tach needle seems to leap toward redline, accompanied by the GSX-R literally leaping toward the next corner. While by no means a transition that we would label explosive, the increase in power and acceleration is dramatic, aided by the fact that the bike weighs less than most 600s. As long as you're up to the task, the gearbox's closely-spaced ratios are ideally suited for keeping the wailing powerplant on the boil, resulting in forward progress that easily rivals--if not surpasses--many of today's best sportbikes. For hard proof, look at the GSX-R's 10.26 second @ 135.6 mph quarter-mile time, or its astounding 172 mph top speed. Slowing this forward progress is ably handled by the new downsized four-piston caliper front brakes. Despite their smaller size, the power, feel and modulation is top-notch, promoting ultra-deep corner entries.

Coupled with its brilliant chassis, the GSX-R's incredible motor puts the Suzuki into rarified performance company. Anytime you combine such acceleration and handling attributes into a cohesive package such as this Suzuki, a landmark sportbike usually results. There are plenty of bikes out there with performance that is right at home on the racetrack, but this is a machine with a personality that has you wondering if number plates are available as an accessory. How good is the new GSX-R750? Former 500cc World Champion Kevin Schwantz commented after riding it, "I'm telling you, if I had this bike at Daytona in '88--just the way it sits right now--I could have won the race easily." Who are we to argue?

Although the new GSX-R's fuel injection throttle bodies are smaller at 42mm (left), the inlet and outlet diameters are larger than the old style (right). This venturi effect helps maximize intake velocity for better all-around performance.

SUSPENSION SETTINGS

FRONT: Preload: 2 lines showing; Rebound damping: 1 turn out from full stiff; Compression damping: 1 turn out from full stiff.
REAR: Preload: 23mm from top of shock threads to top of spring; Rebound damping: 1 turn out from full stiff; Compression damping: 1 turn out from full stiff.

Test notes
+ Most powerful 750 motor we've tested
+ Fantastic chassis
+ Better midrange, smoother throttle response
- Needs revs for best acceleration
- Still some driveline lash
- Might embarrass your buddy on his R1/CBR/ZX-R
x If this bike doesn't make you want to head out to the track, you need help

Specifications

Suzuki GSX-R750

Suggested retail price: $9399

ENGINE

Type: Liquid-cooled, transverse, inline, 4-stroke four
Valve arrangement: DOHC, 4 valves/cyl., shim-under-bucket adjustment, 16,000 mile intervals
Displacement: 749cc
Bore x stroke: 72.0 x 46.0mm
Compression ratio: 12.0:1
Carburetion: Electronic fuel injection, 42mm throttle bodies
Transmission: 6-speed

CHASSIS

Front suspension: 43mm inverted cartridge fork, 4.9 in. travel; adjustments for spring preload, compression and rebound damping
Rear suspension: Single shock absorber, 5.1 in. travel; adjustments for spring preload, compression and rebound damping, ride height
Front brake: 2, four-piston caliper, 320mm discs
Rear brake: Two-piston caliper, 220mm disc
Front wheel: 3.50 x 17 in., cast alloy
Rear wheel: 5.50 x 17 in., cast alloy
Front tire: 120/70ZR-17 Dunlop D207 Sportmax radial
Rear tire: 180/55ZR-17 Dunlop D207 Sportmax radial
Rake/trail: 24 deg./3.8 in. (96mm)
Wheelbase: 55.5 in. (1410mm)
Seat height: 32.7 in. (830mm)
Fuel capacity: 4.8 gal. (18L)
Weight: 426.0 lb. (193kg) wet; 397.2 lb. (180kg) dry
Instruments: Tachometer, digital LCD display with speedometer, tripmeter, clock, coolant temperature gauge; lights for low oil pressure, neutral, high beam, turn signals, low fuel level

PERFORMANCE

Fuel consumption: 37.4 to 42 mpg, 39 mpg avg.
Top speed: 172 mph
Quarter-mile: 10.26 sec. @ 135.6 mph
Roll-ons: 60-80 mph/4.11 sec.
80-100mph/4.34 sec.

GSX-R750 Timeline

Not many motorcycle models have a 15-year life span. The GSX-R is one of those special few--an additional achievement considering Suzuki's relentless technological march. Although almost every model year brought improvements to the bike that was the harbinger of the Japanese sportbike wars, six landmark models stand out in the history of the Gixxer.

1986 The GSX-R750G--the bike that single-handedly initiated the laser focus of the sporting machinery we enjoy today--arrived on U.S. shores a year after its release to the rest of the world. Sporting radial tires on a short (for 1986) 57.3-inch wheelbase with a wet weight of 464 pounds, the GSX-R provided a rolling example of Suzuki's complete focus on lightweight and performance over most other considerations. A true, street-legal racebike, the Gixxer's hard core ergos and its lack of convenience features (such as a steering lock) screamed, "Take me to the track!" Suzuki formed the GSX-R National Cup Series with a purse of $240,000 to help riders pay the $4399 sticker price of the 750.	1988 Although the Suzooks were kicking butt in production racing, for the release of the GSX-R750J Suzuki went back to the drawing board to produce an all-new platform. The wheelbase was shortened to 55.1 inches. The wheels shrunk in diameter to a trend setting 17.0 inches. To reduce drag by 11 percent, the fairing was redesigned. But the 750 didn't get smaller everywhere. The frame was beefed up for 60 percent more rigidity while the fork stanchions grew to 43.0mm. The more oversquare 73.0 x 44.7mm bore and stroke helped to bump the redline up to 13,000 rpm. Holes sprouted in the fairing to direct cool air toward the airbox. Unfortunately, the GSX-R's heft grew to within five pounds of the next lightest competitor at 490 pounds. The retail price also blossomed to a class-leading $5199.	1990-1991 Borrowing heavily from the Suzuki factory racing effort, the GSX-R750L and M models underwent major changes in the engine and the suspension, spread out over two model years. Minor frame tweaks--such as a 0.6 inch longer wheelbase--slowed steering but improved handling. The engine returned to the original Gixxer's bore and stroke specs of 70.0 x 48.7mm to please horsepower hungry race tuners at the expense of stock performance. Valve actuation switched from one rocker arm for two valves to one per valve. Screw-type valve adjusters gave way to shim-under-bucket. Mixture flowed from 38.0mm slingshot carburetors. The 4-into-2-into-1 stainless steel exhaust gave better ground clearance than its recent predecessors. A fully adjustable inverted fork with 41.0mm sliders graced the front while an equally tunable remote reservoir shock slid into the rear. The rear wheel widened to 5.5 inches and a new, more aerodynamic fairing--complete with a cover over the headlights--gave the Suzuki a more aggressive look. Wet weight crept up to 497 and 510 pounds in '90 and '91, respectively. The sticker continued to climb to $6199 and then to $6499.
1993 Once again, a year after the rest of the world enjoyed the latest, greatest--and, most importantly--liquid-cooled Gixxer, it arrived on American shores as the GSX-R750WP. Water-cooling and the engine's ability to withstand the heat generated under severe racing conditions was clearly another nod toward Suzuki's racing intentions for the GSX-R. Still, many of the old, oil-cooling techniques--such as oil-injection piston cooling--augmented the new water jackets. The engine also received the highest compression ratio of its class, at 11.8:1. The frame underwent further strengthening as did the curved swingarm that first appeared in '92. The water pumper weighed in at a beefy 525 pounds, wet. The price of admission was raised to $7299.	1996 The introduction of the GSX-R750T marked the end of the Suzuki's muscle-bound period--lean and mean became the operative words. The trademark (but dated) cradle-frame design was traded in for an aluminum twin-spar set-up that provided a direct link from the steering head to the swingarm pivot. The new frame offered twice the torsional rigidity while weighing in at seven pounds less than the previous version. Hung under the new frame, a smaller, lighter, more powerful engine was force-fed combustibles thanks to a set of electronically controlled 39.0mm carburetors and the Suzuki Ram Air Direct (SRAD) system. Weighing in at 453 pounds, wet, the Suzook's mass dropped below that of the original '85 GSX-R. In fact, the size of the 750 dropped into what had previously been 600cc territory. Still, not everything shrunk. A massive 6.0-inch-wide rear wheel wedged its way into the swingarm. Although the $8999 price tag knocked on the door of the $9000 barrier, 1996 was the year that the Gixxer returned to the forefront of three-quarter liter technological wars.	1998 The big news about the GSX-R750W was the introduction of fuel injection. The SRAD airbox crammed the atmosphere into 46.0mm throttle nozzles where it was forced to mingle with the fuel spraying from the injector bodies. To further improve throttle response, the engine management system accounted for engine rpm, throttle position and water and intake air temperatures to optimize the mixture for low and high rpm conditions. A slightly taller windscreen enabled street riders to see the instruments. Weight stayed constant at 453 pounds, but the price continued upward to $9299. --E.B.

Sport Rider opinions

Remember the good old days, when 600s occasionally did well in 750 Supersport and broke the Suzuki monotony? When racers get their hands on the new Gixxer, those days will be gone. At a recent track day, I was having a blast on the new Suzuki surprising guys with number plates and passing old GSX-Rs on the straights; I'd be pretty worried if I was racing one of those dinosaurs right now. The new model is just plain faster and easier to ride-and by a huge amount on both counts. I was never really fond of the previous model-the fuelie version-but the new injection setup and riding position go a long way toward making the 2000 a nicer streetbike as well as a racebike. I still find it hard to ride smoothly at lower speeds, though. The injection is super-rich off the bottom, which is great for the track but makes it a bit unpredictable when trolling around. I guess this bike's just not meant to be ridden, well-slow.

In a way I'm kind of bummed that the new GSX-R is so good. Remember in '97, when the GSX-R600 came out a year after the 750, and everyone raved that it was so great-even better than its bigger brother? I may just have to replace my poor little Gixxer next year. -Andrew Trevitt

From the first moment I pointed the new Gixxer's front wheel down my favorite tight'n'twisty road, I knew that Kunitsugu's raves were, if anything, an understatement. This particular road convulses, rather than undulates, and rewards smooth throttle response. Throw in varied road conditions-a little sand here, a rock there-that remain hidden around blind curves until the last minute to tax a bike's ability to change lines, add some smooth pavement followed by a variety of bump sizes both on the straights and in corners for the suspension to chew on, and you've got the perfect road test area.

The GSX-R soaked it all up and asked for more without a single bead of perspiration forming on its brow. I stopped at an overlook to reflect on the ride while the Gixxer idled impatiently-like my dog begging me to throw the ball one more time. Who was I to refuse? I went back down only to ride back up and continue with the loop I had planned. As I left the canyons-heading for some higher speed corners-I smiled to myself. Sometimes, I enjoy riding without the boys. They'd only want to swap bikes periodically. And the 2000 GSX-R750 is one of those motorcycles that won't let me play well with other children. Mine, mine, MINE! -Evans Brasfield