by Neale Bayly
Sitting in the pit area of the Santa Monica raceway in Misano, Italy, I find myself feeling a little bewildered. Sharing my thoughts with some of the other journalists attending the world press launch of Suzuki’s new GSX-R 600, I find out I am not alone in my confusion. How can I write about this bike without sounding like a factory brochure?
What do I write about a motorcycle that’s about as perfect as anything I have ever ridden on a racetrack. Outside of some minor suspension and lever adjustments, all I have to do is sit on it and twist the throttle. No fueling glitches, no brake fade, no instability. Just a lightning-quick, featherweight 600cc supersport machine that has been designed with one goal in mind, “to own the racetrack.”
Prior to putting the bike through its paces, we enjoy a lengthy and detailed press conference to learn about the many, complex changes the GSX-R 600 received this year. In an effort to find class winning horsepower, the fuel-injected engine has undergone a total redesign. Factory literature shows 4 percent more power, and with the assistance of ram air this figure is quoted as 126 hp.
Peak torque is now listed as 3 percent stronger. This is achieved in part by the use of a new fuel injection system, which is 370 grams lighter than last year’s. Where the 03 used four, single-barrel throttle bodies, the 04’s feature dual, double-barrel units with Suzuki Dual Throttle Valve (SDTV). Containing two butterfly valves inside the throttle body, the primary is controlled by the rider, the secondary by the bike’s smaller, lighter Electronic Control Module (ECM). Reading information from sensors located on the crankshaft, the gearbox and the throttle, the ECM uses a stepping motor. This opens and closes this secondary butterfly, depending on the engine rpm, the gear position, or how much throttle the rider is dialing in. The result is a feel that is similar to that of CV carburetors, allowing the bike to pull strongly from as low as 6000 rpm. Pretty amazing when you think it revs to 15500 rpm!
The whole fuel injection system is a lot simpler, requiring less connecting poles and tuning links. Throttle body pitch has also been changed, and this allows the airbox to be 10mm shorter and 20mm narrower. It also means the gas tank can be narrower. Intake efficiency is further improved with this year’s injectors being a multi-hole type, instead of the single pintle type previously used. Better fuel atomization, quicker throttle response and improved atomization are responsible for 1 percent of the GSXR’s torque increase.
Inside the engine, reciprocating mass is reduced by 5 percent thanks to titanium valves, lighter pistons, camshafts, valve buckets and more. Displacement, bore and stroke are unchanged, but compression ratio has increased to 12.5:1 from 12.2:1 with the use of flat-top pistons. Normally, this would be achieved by raising the piston dome, but Suzuki’s engineers didn’t want there to be any chance of the pistons hitting the valves. So, they achieved the compression hike by using a more compact combustion chamber.
Providing the titanium valves a home, the new cylinder head has been through the total re-design process and now weighs in 80 grams lighter. As part of this diet, the cylinder head bolts have been reduced by 3.5 grams for a total saving of 35 grams. And the cam housing bolts are 1.4 grams lighter for a further 28-gram loss. Below the flat-top pistons, the connecting rods are 3mm shorter and attach to a new crankshaft that features slimmer journal diameters — 30mm instead of 32mm. This is to optimize crankshaft balance and reduce mechanical loss.
No stone has been left unturned, and looking into the gearbox shows closer gear ratios and a totally redesigned shift fork. I have no complaints about the shifting, only using the clutch for down shifting as the next ratio is effortlessly selected whenever needed. The nonadjustable cable clutch is very light, with a 25 percent reduction in the spring rate. Initial load has been raised by 4 percent however, to deal with the engine’s extra power.
Moving to the chassis, the GSX-R gets an all-new, thinner aluminum twin-spar extrusion frame. Overall height is increased by 1mm, while trail is 3mm sharper at 93mm. Rake is 23.25 degrees compared to last year’s 24. The wheelbase remains the same at 1,400mm, as does the bike’s 715mm width.
Finished in satin black, the frame also differs from last year’s bike with the removable aluminum sub-frame attaching directly to the frame. The seat rails are now made of cast aluminum, as is the cast bridge that runs between them. And the whole plot is quoted as being more crash resistant. Attached to the rear of the frame the new swingarm features some serious bracing. Looking a lot like last year’s swing arm with the braces welded on top, it shares the same length, height and width. The welds are actually very smooth, and the unit looks extremely solid.
Up front, Suzuki has chosen a Showa 43-mm inverted fork for increased rigidity and overlap. Fully adjustable for all the usual stuff, I only make a couple of changes on the second day of testing as my speeds pick up. Exiting the high-speed left hand turn onto the back straight around 120mph, the front end is starting to feel vague as the pace increases. I have a quick word with Suzuki’s test rider Mr. Murata, which results in him dialing in more rebound up front and more compression out back. Putting a little extra weight on the front end, as well as slowing it down a bit, does the trick, allowing me to push harder through the turn.
The overall suspension settings are actually remarkably close to showroom stock, with the exception of a little extra pre-load up front to deal with the high-speed braking at the end of the back straight. Out back, a little extra compression has also been added. The rear shock itself is a 46mm Showa unit, and differs from last year’s with a thicker diameter internal rod, as well as being slightly shorter. Adjustable for the big three, it performs flawlessly over the two-day test.
At the bottom of the inverted forks, the GSX-R 600 rolls on the same 17-inch three-spoke alloy wheels as last year’s model. Running the same 180/55 ZR 17 rear and 120/70ZR 17 front, the bikes we ride are equipped with Bridgestone BT014SFs. These are for Europe only, and Dunlop D218s will be fitted for us here in America. Full marks to the Bridgestone tires. With air temperatures hovering around the 37-42 degree mark, and cold winds blowing across the Santa Monica raceway, they give a whole lot more grip than I originally thought possible.
Attached to the attractive wheels, this year’s brake discs are 20mm smaller at 300mm and 0.5mm thicker. They also are 20 grams lighter. Clamping down on these new rotors, Suzuki uses Tokico radial-mount calipers which allow for more rigidity and improved braking. Lightly squeezing on the six-way adjustable lever at over 150mph scrubbed off the required speed to enter the horseshoe with absolutely no drama. There is no harshness in the operation, the brakes just progressively biting harder the more I pull. Riding the same bike for both days, the brake action is just as strong during the last session as it is during my first.
Partly responsible for this incredible set up, the front master cylinder is a radial-piston affair. Unlike a conventional piston that works horizontally against the lever, the radial piston is positioned vertically, allowing a more direct force from the lever to the piston. This gets more fluid to the brake calipers and is said to improve feel and feedback.
Visually, the bike certainly shows its GSXR heritage and has been styled this year for a more aggressive look. Up front, the vertically stacked headlights replace the old side-by-side jobs, and sit in a narrower, more aerodynamic fairing. The two-stacked headlights consist of a projector-type on the bottom for low beam and a multi reflector type up top for the main. Punching the smallest hole possible through the air, even the GSX-R’s turn signals have been given a new more aerodynamic shape, as well as being lighter. Out back is the tight-looking tail section, with two sets of seven horizontal LED lights.
The gas tank is narrower and shorter this year, which makes life easier for the rider during cornering transitions or when getting hard on the brakes. I like being able to hook my outside leg under the small lip while resting my elbow on my knee, and it is helpful during tuck and squeeze time in the fast sections. The seat gives no complaint, serving as a useful work platform to slide on and off the bike. It also gives enough room for my near 6-foot frame as I make hot laps onboard the high-revving six.
Out on the track, a lightning quick glance shows 245 kmph (over150mph) on the digital speedometer, with the tachometer needle hitting redline at 15500 rpm in fifth as I approach the horseshoe. Rolling off the throttle and onto the brakes, I slide rearward to keep the back wheel on the floor. Down shifting, I dive left and rail round on a steadily increasing throttle, before nailing it back up to redline. Briefly hitting the rev limiter, it is time to get back on the binders before the tight uphill right-hander that leads to the first of Misano’s two chicanes.
Hanging way off to keep the tires as upright as possible, I feed in the power and hold the same gear up the hill, before sending brake fluid to the eight pistons down at the front wheel. Clipping the curb into the chicane, I effortlessly flick the bike left for the run up to the top horseshoe. Third gear ends a tad bit short of the corner, but to save two shifts I hold it on the limiter before arcing through the corner. Accelerating to redline, I indulge in the intoxicating intake roar that resonates as the engine rips past 9000 rpm. Flicking through the chicane, a good drive has the bike screaming onto the front straight, knee puck skimming the tarmac as I attempt to ignore the concrete way 3 feet to my right.
Flashing across the start/finish line it is time to start another lap. Riding harder and more aggressively on the 355-pound Suzuki GSX-R600 than I have in a while, the bike takes it all in its stride. Totally in control, it exudes confidence from every pore and is going to make a hero out of anyone that takes it to the track. Now all I have to do is figure out how to write about it without sounding like an ad campaign.