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2003 Suzuki GSX-R1000 and a bit lighter for next year, knock yourself out, Mr. Suzuki Engineer. Just make sure we get to sample it on a racetrack that does it justice. Hey, I've got an idea ... how about Phillip Island in Australia, mate? When you build a motorcycle that makes even the brave tremble in their boots, you'd better take them somewhere suitable to ride it. Somewhere that allows the big fella to really let loose. What better place than Phillip Island? So Phillip Island it was. Phillip Island and the GSX-R1000: A match made in heaven. You can read about the changes Suzuki made to the bike to take off 4.4 pounds while adding some torque and horsepower elsewhere within this story. I just want to get back to Phillip Island for a minute or 10. Anyone who tells you that throwing your leg over the GSX-R1000 isn't a bit intimidating is lying. Okay, the Mat Mladins of the world don't count. I'm talking about the rest of The Beast Wit'hin The changes to the GSX-R1000's powerplant begin with the intake system. Obviously already fuel-injected, this year's system has been upgraded. For starters, the control module now features a 32-bit processor instead of the 16-bit CPU found on the previous model. Those changes mean that the module can now calculate things faster and with more accuracy - and that ultimately means better efficiency and throttle response. It also means reduced exhaust emissions, according to the good folks at Suzuki. The controller, which is also smaller than last year's, works in conjunction with new, dual, double-body throttle bodies that replace last year's four individually cast single-barrel bodies, which were joined together via connecting poles. The material used in making the delivery pipes (the tubes through which the fuel flows to the injectors from the fuel pump) has also changed to resin (last year's combined aluminum pipes and resin pipes). The result is a reduction in weight (372 grams), and the new system allows for the use of just one tuning link rather than the three needed on last year's system. The size of the throttle body is mostly unchanged with a 50mm inlet diameter and 42mm throttle valve diameter, but the biggest difference is that the actual height of the throttle bodies are now 7mm shorter. The injectors are smaller and lighter (28 grams), and the spray nozzles have been altered with each having four holes rather than the pintle type injectors found on the '02 model. The different nozzle design results in more efficient combustion and better torque. The injectors now enter the throttle body at a steeper angle (60 degrees to the throttle body's centerline), further increasing combustion efficiency and engine output at middle to full throttle. Exhaust efficiency (and power) has also been improved on the new model, thanks mostly to an increase in muffler capacity. The outside diameter of the new muffler is 10mm larger than last year's model, with the inner diameter increased some 8mm. The length of the muffler has also grown, up to 520mm from last year's 420mm. Obviously, all of this adds up to more capacity, with the muffler going up from 4900cc to 6900cc. The exhaust system is now all titanium. whereas previous models featured a combination of stainless steel and titanium. The weight savings is 600 grams. Hydrocarbon emissions have been reduced by about 17 percent, according to Suzuki. The credit on this goes to the SET (Suzuki Exhaust Tuning Valve) System, a system in which a butterfly valve is installed in the pipe between the collectors and the canister and is driven by a servo. The 988cc engine underwent a few changes for '03. One of the changes was to help make the powerplant (the cylinder head in particular) a bit more compact. One detail that contributed to this was the change in the center-tocenter pitch between the throttle bodies and the cylinders, which is now 80mm. This allows the intake ports to be straight on a horizontal plane, resulting in more efficient combustion, while being more compact. The cylinders on the new model are lined with SCEM (Suzuki Composite Electrochemical Material), a nickel/phosphorous/siJicone/carbide coating which supposedly improves heat transfer and lets them run a tighter piston clearance. The GSX-Rl000 uses an integrated upper crankcase and cylinder, which increases rigidity and reduces weight (350 grams). To further save weight (another 50 grams). the extemal oil hoses have been eliminated, and the oil that runs to the camchain tensioner adjuster from the upper crankcase now runs internally through the upper crankcase and cylinder head. The six-speed transmission on the GSX-R1000 features the same gear ratios as last year's model. The rest of the transmission is also unchanged. In an effort to further improve torque, Suzuki has added ventilation holes between adjacent cylinders on the 1000. Each cylinder wall has a 35mm-diameter ventilating hole, which helps reduce pumping losses inside the cylinder, according to Suzuki. The air that creates such pumping losses can move to the neighboring cylinder and the magneto chamber reducing the pumping pressure in that cylinder. It all adds up to less mechanical power losses and improved power output (2 percent at high engine rpm). Other parts that have been changed to aid the Suzuki's dietary program include a thinner secondary balance shaft (30 grams) and a lighter camshaft (intake - 45 grams, exhaust 35 grams). 24 MARCH 5. 2003 cue I e n e _ s I'll admit to being a bit intimidated us. Those of us who would be plenty by the new bike. I'd ridden both previ- happy with a Yoshimura Suzuki GSX- ous models. I'd crashed the 2001 R750 Superbike ... Last year's GSX-R 1000 was sickly model at Willow Springs (cold tires, cold track, sun in my eyes, leathers fast, accelerated faster than an old too tight, visions of a bouncing check man's cholesterol level at a donut or two dancing in my head, blah, shop, and felt pretty damn light in the blah, blah) and had spent a solid day process - considering the fact that it on the 2002 model at the outside was an open-class sportbike. Know- track at Las Vegas Motor Speedway. ing that this one was supposed to be Without incident, I might add. So I even faster, with a bit more torque knew first hand that the GSX-R1000 and a bit less weight ... well, those presents itself as quite a bit of motor- among us at Phillip Island who cycle. With that in my head (the throt- claimed to have been not the least bit tle goes both ways, blah, blah, blah), I nervous, I can say nothing to except - calmed myself prior to throwing my "Liar, liar, pants on fire." leg over the bike for the first time.