Since the dawn of the GSX-R, Suzuki has constantly developed the lineup by mixing and matching designs and components among the two or three models. New elements one year are used to update the other models the next year in an ongoing leapfrog of updates, with the majority of new tech showing up on the bigger bikes first, then trickling down to the 600. Continuing this tradition, the 2004 GSX-R600 incorporates many of the design features and updates of the '03 GSX-R1000 plus a few new tricks shared with the similarly changed GSX-R750.
While the long list of features is outlined in the technical sidebar (page 58), the essential theme of the '04 600 is evolution through a host of detail changes that Suzuki has developed from past experience. Practically every new item on the '03 GSX-R1000 finds its way onto the 600, including styling, chassis and electrical updates. But whereas the 1000's engine was little changed last year, the 600's mill gets a fairly major makeover to lighten internal components and reduce friction, steps that allow the motor to spin 1350 rpm higher than before and make additional much-needed horsepower.
The year 2003 was incredible for the middleweight class, one that saw the market somewhat shaken by the introduction of Kawasaki's 636cc ZX-6R. While the 6R didn't win our shootout ("Weapons of Mass Deduction," June '03), it certainly raised our expectations of middleweight power outputs. And the '03 Yamaha YZF-R6 used its incredible lightness--and litheness--to win that comparison test and go on to almost steal BOTY honors. And where was the GSX-R600 in all this? The only unchanged model of the foursome, the Suzuki was let down to a certain extent by braking and suspension performance, but mostly by its lackluster engine.
Introducing...
Our first experience with the '04 GSX-R600 showed that Suzuki has indeed addressed the power issue, as the new bike exhibited serious steam at its introduction in Misano, Italy. Whereas the old mill made good peak horsepower, the spread was such that you really had to work to keep it spinning if you wanted to go anywhere. Incredibly, the new mill winds happily from 8000 rpm all the way to 16,000, pulling hard right to the rev limiter. The irony of it all is that the new bike's sound--the intake and exhaust combine in a wonderful symphony near redline--makes you want to rev the crap out of it, even when you don't have to.
It's the sound and power that leave a lasting impression after a racetrack session on the GSX-R, but other aspects of the package are equally stellar. The new radial-mount brakes provide incredible stopping power with excellent feedback--the Tokico calipers have two pads each, and the reduction in bite compared to the four-pad versions makes them much less touchy. The compacted riding position and narrower tank make the whole bike feel smaller, and the more aggressive geometry lightens steering substantially. Turn-in is not R6 quick by any means--and the GSX-R is still 14 pounds up on the flyweight Yamaha--but it is a huge step in the R6's direction compared to the old bike.
The beefier inverted front fork makes for more precise feedback as you arc into turns hard on the brakes, and both ends are nicely compliant over wavy pavement. Use the newfound power to spin the rear Euro-spec Bridgestone BT-014 on corner exits and the GSX-R tracks straight, simply digging in and pushing you forward. The little mill makes enough jam now that squat and wheelies come into play, and if you're not careful--or if you just want to have fun--the front wheel will come off the ground exiting second-gear turns. Just make sure to set it down straight, because that sharpened steering makes things a bit more twitchy now--whereas the old bike didn't really need a steering damper (and we ditched the too-stiff unit on last year's test bike), this one does.
It's all incredible fun around a racetrack, as the little Suzuki's cacophony of sounds eggs you on, begging you to use more and more revs each lap. There are, however, a couple of chinks in the Suzuki's on-track armor. One is in the front brakes--flawless otherwise, they are unpredictable when you release the lever entering a turn and sometimes hang up, slowing you more than you want. It's more the unpredictability rather than the fact that they act that way that's unnerving. Second, the light throttle-return spring and the free-revving motor's nature means getting on the throttle requires care, as the off/on transition is a bit abrupt in the fun part of the powerband.
While we like the GSX-R's radial-mount master cylinder and that it incorporates a bleed screw, the interfernce you see here makes adjusting the lever angle almost impossible. Adjustment is further limited by the banjo fitting underneath contacting the fork leg.
Meanwhile, back at the ranch
The improved power and racetrack abilities of the new GSX-R certainly incur a penalty when it comes time to tool around town. The shortened fuel tank closes up the riding position slightly compared to the old 600, but the raised seat height effectively lowers the clip-ons, and the reach to the bars feels almost more of a stretch than previously. Below 8000 rpm the powerband has more peaks and valleys than the Swiss Alps. Pull away from a light with the revs at one of those dead spots and you'll have trouble getting out of traffic's way. And at low revs the fuel injection's fluffiness exaggerates a little bit of driveline lash into quite sloppy shifting that no amount of care can remedy. The brakes need some heat in them to work effectively, heat you can't generate around town, and every tester's initial impression was that the pads weren't broken in, with the brakes numb and requiring a bit of extra pressure. All other aspects of city riding are quite acceptable; the GSX-R starts immediately on cold mornings (and fast idle is now automatic) and can be ridden away without waiting. The mirrors are large and spaced far enough apart that you can easily see traffic directly behind. And while the seat is high, the bike's thinner midsection means medium-height riders can still touch the ground with both feet flat.
On the highway, it's not long before the Suzuki has you squirming to relieve pressure points on both your butt and hands. Gone is the plush seat of the earlier models, replaced with a narrower, firmer cushion, and the relatively lower clip-ons feel more angled back, placing extra pressure on the center of your palms. There's a bit more wind buffeting from the slimmer windscreen and fairing, which somewhat helps to take the weight off your hands, but still, overall it's a less comfortable ride than previously.
Get to the twisties, though, and it's all worthwhile--the GSX-R is more of a package, making quick work of canyon runs with graceful ease. The riding position and shorter, thinner tank make sense when you get aggressive, and in a hunkered down stance your arms are automatically unweighted. Taller riders will appreciate the GSX-R's revised ergos more than shorter riders, as they can better cope with the reach to the bars. The fluffy bottom end turns into seamless throttle response at lower rpm, almost making up for the lack of midrange power--almost. And getting some heat into the brakes makes all the difference, as they are one-finger strong and easily modulated.
After every run on the little Gixxer our testers were left shaking their heads--try as we might, it's hard to find fault with the Suzuki's prowess. The traditional GSX-R stability is there in the faster, bumpy turns despite the quicker steering, and the suspension's quality feels a large notch up on the previous model. Damping in general is stiff, while spring rates seem a bit soft--the rear suspension has no free sag with the standard preload setting, and heavier riders will find the rear squatting a bit much, while lighter pilots will feel it topping out. Still, aside from a bit of harshness over smaller bumps the suspension works great with that combination, soaking up larger hits with little fanfare and providing a planted feeling that fuels your confidence. Just as on the racetrack, the 600 drives straight if you happen to get a bit aggressive with the throttle and spin the tire--and you have to be pretty rambunctious to get to that point, as the standard U.S.-spec Dunlop D218s offer excellent grip. A version of the company's D208, the Dunlops suit the GSX-R well, with quite neutral steering no matter the lean angle.
Suzuki's work inside the engine to reduce pumping losses and friction has paid off in more than just increased power. Whereas the old bike had excessive engine braking, the '04 model has very little, which goes a long way toward easing the off/on throttle transition and helping to keep your speed up. Even in turns where you drop below the magical 8000-rpm mark, if you manage the throttle to effectively navigate the lumps in the power curve, you won't lose too much time to a bike with more midrange. Up the pace to the point where you approach racetrack aggression and speeds, and the same characteristics come into play--the throttle is a bit abrupt at high revs and little load, and the brakes develop that unpredictability when you release them entering a turn. That the Suzuki gives you the confidence to even get to that point on the street is the amazing part.
It's easy to see that the GSX-R600 is a big improvement over its predecessor. Suzuki has kept most of the characteristics that we liked so much about the previous version, and handily addressed its shortcomings. We can't wait to toss it in the ring with the other incredible middleweights--stay tuned.
2004 SUZUKI GSX-R600
ENGINE
Type: Liquid-cooled, four-stroke, inline-four
Valve arrangement: DOHC, four valves/cyl., shim-under-bucket adjustment
Displacement: 599cc
Bore x stroke: 67.0 x 42.5mm
Compression ratio: 12.5:1
Induction: SDTV fuel injection, two dual-body 38mm throttle bodies
Transmission: 6-speed
CHASSIS
Front suspension: 43mm inverted cartridge fork, 4.7 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
Front brake: Two radial-mount four-piston calipers, 300mm discs
Rear brake: Twin-piston caliper, 220mm disc
Front wheel: 3.5 x 17 in.; cast-alloy
Rear wheel: 5.5 x 17 in.; cast-alloy
Front tire: 120/70-ZR17 Dunlop D218F Sportmax
Rear tire: 180/55-ZR17 Dunlop D218 Sportmax
Rake/trail: 23.25 deg./3.7 in. (93mm)
Wheelbase: 55.1 in. (1400mm)
Seat height: 32.4 in. (825mm)
Fuel capacity: 4.5 gal. (17L)
Weight: 429 lb. (195kg) wet; 402 lb. (182kg) dry
Instruments: Analog tachometer, LCD panel display with digital speedometer, odometer, dual tripmeters, clock, coolant temp; shift light; warning lights for neutral, high beam, turn signal, low fuel, EFI warning/oil pressure/coolant temp
PERFORMANCE
Quarter-mile: 10.58 sec. @ 130.5 mph (corrected)
Top speed: NA
Roll-ons: 60-80 mph/3.76 sec., 80-100 mph/3.86 sec.
Fuel consumption: 32 to 42 mpg, 38 mpg average
TEST NOTES + -
+ Major power from 8000 rpm to redline
+ Solid chassis and suspension
+ Incredible brakes
- Wheezy below 8000
- Brakes can be unpredictable
- Comfort is a step backward...
x But we'll gladly make that trade-off
SUGGESTED SUSPENSION SETTINGS
FRONT:
Spring preload: 4 lines showing
Rebound damping: 0.75 turns out from full stiff
Compression damping: 1.75 turns out from full stiff
Ride height: 1.75 turns out from full stiff. 5mm fork tube protruding above top triple clamp
REAR:
Spring preload: 9mm thread showing
Rebound damping: 1.25 turns out from full stiff
Compression damping: 1.5 turns out from full stiff