Suzuki GSX-R Series

Suzuki GSX-R

1991 GSX-R1100 in team Yoshimura colors
Manufacturer	Suzuki
Production	Since 1985
Class	Sport bike

The Suzuki GSX-R is a series of sport bikes made by Japanese manufacturer Suzuki. Current models are the GSX-R125 and GSX-R150 which will be on sale in 2017; GSX-R600 which was manufactured from 1992 to 1993, and since 1997; the GSX-R750 since 1985; and the GSX-R1000 since 2001.

The first GSX-R of 1984 was a breakthrough model and the closest that any Japanese manufacturer had yet come to building a "race bike with lights". Throughout the 1970s the big four Japanese manufacturers had built bikes with a similar architecture: steel double loop frames, air-cooled inline fours with either SOHC or DOHC configurations.

At the start of the 1970s two valve per cylinder heads were ubiquitous, by the end of the decade four valve heads were available on the high end bikes. The similarity of the designs across brands and years led to the coining of the term "UJM" for Universal Japanese Motorcycle, which began with Honda's CB-750 of 1969.

These bikes were available in a variety of sizes from 350cc to 1200cc from all four of the Japanese manufacturers, and beginning in 1976 served as the basis for production-based race bikes in the American Motorcycle Association (AMA) Superbike Series. As a result of the experience on the race track it became obvious that the big UJMs were not ideal for racing. Weight was high, frames lacked stiffness and flexed in disturbing ways, power from the big motors overwhelmed the tire technology of the day.

Beginning around 1980 all four manufacturers began to modify the UJM formula in different ways to achieve performance advantages on the track and product differentiation in the market. In 1982 Honda introduced the VF series, which used a V4 rather than inline-four motor configuration. The first model year only cruiser style bikes were offered, but in 1983 the first sport bike based on the V4 became available:the Honda VFR-750 Interceptor. AMA rules for Superbike racing were changed in 1983 to decrease maximum engine size from 1025cc to 750cc. The Honda Interceptor was ready to compete in this new category. In addition to the innovative V4 engine configuration, it was liquid cooled, and it sported a rectangular tube steel frame, to increase stiffness, as opposed to the more traditional round tubes of the UJM era. The Interceptor was a breakthrough for Honda, and it won many races, including Daytona, and was the second-place finisher in the series. A year later, in 1984 the entire front row at Daytona were Interceptors and Freddie Spencer repeated his win on the V4 Honda.