Suzuki engineers are seeing double: double side-mounted exhausts, that is, just like the good old days. As expected, the GSX-R1000 uses a variation of the Suzuki Advanced Exhaust System (SAES) that debuted last year on the GSX-R600 and 750, consisting of four equal-length head pipes that feed into an under-engine exhaust chamber, positioned to centralize mass. Said chamber houses the SET (Suzuki Exhaust Tuning) valve that modulates exhaust back pressure to maximize torque production across the rpm range, along with the O2 sensor that signals the closed-loop EFI system. Unlike its smaller siblings, however, the 1K uses dual mufflers (constructed from a mix of aluminum and titanium pieces) that offer nearly twice the internal volume for improved exhaust flow.
Big changes to the suspension can be found up front, in the form of the DLC (Diamond-Like Coating) on the 43mm forks that now offer both high- and low-speed compression damping (matching the shock), pleasing track-day geeks the world 'round. Fork offset has been reduced from 30mm to 28mm (increasing the trail figure from 96 to 98mm) to make the bike more stable at lean, and the massive outer stanchions swell to 56mm below the triple-clamps to make the fork more resistant to side loads for more precise steering feel.
Bore and stroke (73.4 x 59.0mm for 999cc displacement) remain unchanged, but pretty much everything else is different. The cylinder head has been completely redesigned, with reshaped intake and exhaust ports that are now 8 percent larger. Exhaust valves have grown 2mm to 26mm and are acted on by more aggressive cams. Even bigger changes can be found upstream in the fuel-injection system, where you'll find a downsized version of the Suzuki Dual Throttle Valve (SDTV). New showerhead-style injectors boast 12 smaller spray holes (compared to four last year) to better atomize fuel, and the secondary injectors have been repositioned at a steeper, 30-degree angle to squirt more directly into the intake ports. Down below, a new, self-adjusting hydraulic clutch (boosted by a radial master cylinder) enables smoother, more predictable and more consistent application of the back-torque-limiting "slipper" mechanism. Lastly, the cooling system has been revamped with a larger, works-type trapezoidal radiator that offers 10 percent more cooling capacity and a reshaped oil cooler that boosts its capacity by 30 percent, the latter fed by a larger-capacity oil pump.
New, thinner-spoked wheels are fitted to reduce rotating mass and unsprung weight even further. Also pared down are the 310mm front brake discs, which shrink half a millimeter to 5mm in thickness. Look closely at the front rotors and you'll notice 12 mounting buttons each (compared to eight last year), the increased heat pathways to the carrier maintaining heat transfer and helping the thinner rotors resist overheating. The rear caliper has been relocated to above the swingarm, a move intended to reduce braking effects on rear suspension action.
Suzuki says the '07 GSX-R1000's ECU offers four times the processing power of last year's nerve center, and those extra megabytes are put to good use operating an innovative engine-management system that allows riders to toggle between three factory-determined performance settings. Calibrated using data mined from Suzuki's MotoGP racebikes, the ECU is pre-programmed with maps that produce power-delivery characteristics optimized for dry, mixed or wet-weather riding conditions. The rider can change the setting on the fly via a three-position switch mounted on the right handlebar. Traction control-it's not just for racing anymore. Also plugged-in this year is an all-new, electronically controlled steering damper (mounted in front of the lower triple-clamp), which uses a solenoid-actuated valve to move a tapered needle that alters oil flow to adjust damping force according to engine rpm and road speed.
