'86 All Japan chanpionship TT-F1,
#50 Satoshi Tsujimoto
Following several model changes in the early years to raise performance and stay in the lead, Suzuki changed the engine of the 1992 GSX-R750 from oil-cooled to liquid-cooled and adopted a more rigid frame with a large, pentagonal cross-section. Hiroshi Iio, chief engineer of the GSX-R series, reveals a secret episode. "We development team members shared a clear goal to realize higher performance, lighter weight and more compactness that facilitated agreement on technical matters," Iio recollects, "But aesthetic matters such as engine's appearance did cause some arguments. For example, we asked Japan's Air Self-Defense Force to show us various aircraft power units as inspiration for the fin shape on our '92 GSX-R750."
For the 1996 model, engine designer Masahiro Nishikawa strove to figure out the most desirable characteristics for a new-generation Supersport. "I frequently visited major superbike championship circuits to collect on-the-spot information," he says. "The answer was an entirely new engine with three-piece crankcases and a side camchain." Combined with the all-new twin-spar frame inspired by the Grand Prix race bikes, this version achieved 19kg weight reduction from its predecessor.
The highly evolved GSX-R750 adopted the catch phrase 'The most advanced GSX-R ever' in 2000. That model's totally redesigned engine featured a new electronic fuel injection system with dual throttle valves - a rider controlled throttle valve and an electronically controlled valve - that enabled optimal fuel injection for greater torque and power, as well as higher combustion efficiency with lower emissions. The new main frame was lighter, with a longer swing arm than the previous model. Together, the innovations offered 2000 GSX-R750 riders overpowering performance approaching that of a one-liter model.
Yukihiro Takasaki has been dedicated to development of the electronic fuel-injection systems in all GSX-R series models since 1999. "As a private race team mechanic I had a close contact with GSX-R750 when I joined Suzuki two decades ago," says Takasaki, "so I was eager to take charge of GSX-R development. Our team was thrilled to complete a new fuel-injection control system that helped to exceed performance of carburetor-equipped competitors. I'm happy to say that Suzuki's fuel-injection technologies are still leading the industry today."