Down in the transmission cavity, the gear ratios are identical to the previous generation GSX-R's, but the final drive is shortened a bit by the fitment of a one-tooth-larger rear sprocket. The clutch is now hydraulically operated (replacing the previous cable-activated unit), and the back-torque slipper-clutch mechanism has been upgraded with modified ramps and four reaction springs instead of three, for smoother operation. Although Suzuki claims the hydraulic actuation-which definitely adds weight over a conventional cable-operated unit-was used for its self-adjustment advantage, we're thinking it's due to stiffer springs fitted to the clutch basket in order to hold the engine's increased power. A hydraulic clutch doesn't need the freeplay necessary in a cable-operated clutch to allow for plate expansion; that extra lever travel can be used to increase the leverage ratio, which allows stiffer springs to be utilized with the same lever effort.
The GSX-R's trademark twin-spar aluminum chassis received a thorough overhaul as well. Utilizing the now-prevalent precision die-casting technology that allows the manufacture of intricate components with less welding, more precise thickness and lighter weight, the frame is composed of five main cast aluminum-alloy sections, instead of the seven pieces that made up the old unit. The reduced number of parts and welded connections cuts even more weight while allowing Suzuki engineers to precisely tailor the amount of flex necessary for good cornering feel.
The new swingarm follows a similar pattern. Instead of the previous stamped aluminum sheets welded to a cast pivot section, the new swingarm is built from three separate aluminum die-castings. As with the new frame, this made it possible to optimize the thickness of each swingarm section, reduce the number of component parts and welding without reducing rigidity, and even cut weight by 200 grams. The overall rear axle position was moved back by 10mm, stretching the wheelbase slightly from 55.3 to 55.7 inches.
Both the 43mm KYB inverted cartridge fork and rear shock now feature high- and low-speed compression damping adjustment in addition to the usual rebound and spring preload adjustment, allowing much more precise dial-in for a particular rider or riding situation. Suspension travel in the front fork has also been increased 5mm, to 125mm, and the diameter of the upper fork tube is now 2mm larger at the lower triple-clamp area for increased rigidity. While rake angle remains the same at 23.8 degrees, the triple-clamp offset has been reduced by 2mm for an increase in trail by the same amount to 98mm. The rear shock linkage has been redesigned, with the link now pivoting directly off the swingarm instead of the frame to allow more room to accommodate the underengine exhaust chamber.
A telescoping steering damper is mounted crosswise in front of the steering head as before, but with a twist: A solenoid valve operated by the ECU changes the damping rate by moving a tapered needle inside the main damping circuit. This allows for less damping at slow speeds for lighter steering, and more damping force at higher speeds, when it's needed most.
Although the front-brake discs are the same diameter and thickness as before, the disc carriers utilize 10 floating buttons instead of eight, which permits the carriers to be thinner, resulting in a 70-gram weight reduction on each side. And the same aluminum alloy rims now come shod with Bridgestone's latest variant of the new OEM-spec-only BT015 radials.