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2001 Suzuki GSX-R1000 felt compliant and, as a matter of fact, I never changed the settings on the bike all weekend. Like I said, the final session was the only session that I really pushed hard in, but I never dragged any hard-parts and I never felt as though the suspension was in need of adjustment. It was all good. There was no chatter or under-steer from the front end, it felt planted and stable, and it provided plenty of quality feedback. The chassis dimensions of the OSX-RI000 are almost identical to the 750's. The OSX-RI000 has a 1410mm (56.4 inches) wheelbase - same as the 750's. It also shares the same rake and trail figures as the 750. with 24 degrees of rake, and 96mm of trail. Weight distribution is biased toward the front with 51.8 percent of the claimed 374 pounds (dry) carried on the front wheel. The twin-spar aluminum frame features one additional engine mount than the 600 or the 750 and it also has thicker outside walls to improve rigidity. The swingarm has been beefed up by using double-box-section aluminum, instead of the single-box design on the 750 - and actuates the rear shock with a progressive linkage. The Kayaba piggyback rear shock is fully adjustable for preload, compression, and rebound dampening - it features a larger 16mm piston rod, to help eliminate fade and improve the shocks consistency when the shock is working overtime. The forks are fully adjustable Kayaba 43mm inverted cartridge forks. They feature the distinctive titanium-nitride gold coating on the lower fork stanchions, to help reduce stiction - and they look really cool as well. Another nice touch is the aluminum steering-stem nut it makes the bike look more refined than a steel eqUivalent. The OSX-RIOOO bas new Tokico differentialbore six-piston calipers that bite into dual 320mm discs. The new anodized, six-piston calipers are supposed to be more powerful, to deal with the added weight and speed of the OSX-RIOOO. The Hayabusa has similar calipers, but the OSX·RI000's are lighter. Combined with new brake-pad material, these brakes are supposed to perform better. The rear brake features a twin-piston caliper with a 220mm disc. The three-spoke, cast-aluminum-alloy wheels measure 3.50 X 17 inches up front, and 6.00 X 17 inches for the rear. The OSX-R 1000 comes with Bridgestone tires in North America - the front tire being a 120/70ZR 17 BTO 11 while a 190/50ZR17 BTOlO is mounted on the rear. The entire family of OSX-Rs has become difficult to distinguish from one another. But the 1000's distinctive front-end gives it away, with the six-piston brakes and the titanium-nitridecoated forks. Even though the bodywork looks identical to the two smaller-displacement bikes, the OSX-RIOOO has different lower fairings that are slightly wider to accommodate the air-cooled oil cooler. overly excited at the prospect of From a handling perspective, the R750. No surprise there (Suzuki matching wet track with potent GSXRI000. We went out and did some laps on Gixxer performed exactly as I predict- claims the GSX-R 1000 is only 10 ed it would - it felt like a slightly pounds heavier than the GSX-R750). heavier, and slightly larger GSX- It handled very well. The suspension Turn-in was crisp and quick, with just a tad more effort required than Qn the GSX-R750 - for which the few extra pounds, and the extra reciprocating mass of the larger motor are probably responsible. I imagine that if the track had been a bit warmer, and if I could have pushed harder through the tight corners, the soft set-up would have needed to be stiffened up a bit. I did break the rear end loose now and again throughout the weekend, but it was more the result of a heavy throttle hand than a chassis weakness. I'm a little bit on the fence in regard to the performance of the brakes. While they were powerful, they clid seem to fade a touch during my last session of the day. I was entering the braking zone for turn 10 at an indicated 181 mph (probably more like high 160s to 170 mph), and although I felt that the stopping power was there, the feel could have been a little bit better. The lack of feel just made it impossible for me to feel comfortable getting too close to the maximum braking threshold. The brakes aren't bad - they're just a little vague. the wet track, and I was very surprised how well the stock Bridgestone street tires performed. The air temperature was around 40 degrees, but after letting the tires get about five laps of heat in them, they were predictable and felt remarkably grippy considering the conditions. The wet conditions prevented me from pushing very hard in that first wet session, but then (thank God) it started drying out toward the end. At that point, I did see an inclicated 165 mph, while leaned over going through the kink they call turn nine, on the back straight. It was a completely wet track at that point - rooster tail and all. I felt like I was at the helm of Miss Budweiser - the Unlimited Hydroplane boat - and not a motorcycle (Yikes!). The track dried out almost com- The fuel-injection system on the OSXRIOOO is virtually identical to the systems on the 600 and 750, except for the throttlebody size, which is 42mm on the OSXRI000. The fuel-injection system's most unique feature is the secondary throttle butterflies in the throttle bodies themselves (right). The system is designed to maintain an optimal intake velocity for the mixture. It's rather simple really: The rider's throttle input controls the opening of the primary butterfly - then the bike's ECM (Electronic pletely for our final session of the day, and I was finally feeling comfortable on the bike, and pushing as hard as the conditions would allow. This was the only session that I was able to evaluate the handling of the bike properly, because it was the only session that I was able to ride aggressively. 26 JANUARY 3, 2001 • eye • e n e _ s Control Module} monitors engine rpm, and gear position, to determine what the optimal intake velocity should be, and then activates a stepping motor (essentially a servo) that Suzuki claims is more accurate, to control the secondary butterfly. This is supposed to not only improve low rpm, full-throttle response, but also to improve response when the rider is trying to pick up the throttle mid-corner. The previous generation fuel injected OSX-R750's had snatchy throttle response when going from off-throttle to on-throttle. Suzuki's new fuel-injection system was introduced on the 750 in 2000, and then on the 600 and 1000 this year. The fuel spray is designed to improve the atomization of fuel, by directing the spray directly at the primary butterfly valve. which further breaks up the fuel particles and improves combustion. There are eight fuel-injection maps stored in the bikes ECM; two maps for each individual cylinder; one for light; and one for heavy throttle loads. The computer determines which map to use based on throttle opening, and engine rpm. The ram-air system is virtually the same as on the 600 and 750. The intake snorkels are located close to the center of the upper fairing where the air pressure is the highest. The four-into-two-into-one exhaust system features ample use of titanium to keep the weight down. The headers, canister, and internal baffies are aJi made of the light stuff. The exhaust system also has a variable backpressure control valve similar to Yamaha's EXUP, or Honda's HTEV. Suzuki calls their system SET (Suzuki Exhaust Tuning), with servodriven cables controlling a butterfly valve between the headers and the canister. The bike's ECM controls the valve's opening by monitoring throttle position, engine rpm, and gear position. The valve controls unstable exhaust backpressure at lower rpms, opening up as the revs rise.