Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/126766
Suzuki (Continued/rom page J) GS 11 00 designer Etsuo Yokouchi now heads U.S. market designs. This is the Japanese-market RG400; the export-market RG600 is nearly identical except for engine displacement. The frame is all aluminum alloy. the engine a water-cooled two-stroke Square Four. U.S. Suzuki denies any knowledge of the RG street bikes and of the DR600. a new four-valve Single with single rear shock suspension. Unlike the RG500 racebike engine shown here. the street bike version has exhaust powervalves as well as rotary valve induction. Randy Mamola rode RG600s for five years. ways to broaden the powerband and maintain adequate cooling for street USl'. Both problems were also encountered in the devclopmem of the company's GT750 two-stroke Triple sold during the 19705. bu! were solved before the bike went into production. Suzuki's enginttrs teslN two-stroke Twins in 400and 50Occdisplacl'ment. bUI decided upon the Square Four design beca use it made more power. The SUlllki men also said thaI the company would not produce sporting versions of the G\'1200GL and GV700GL V-4 cruisers shown in Cycle News recemly. Their comments were backed up by Mr. Etsuo Yokouchi. newly naml'd general managl'r of Suzuki's Motorcycle Engineering Division I. Speaking in Los Angeles. Yokouchi said thl' \'--Is. whill' ideal for customstyled ;"otorcycles built for Ihe American market. are too hea,'y and bulky for SP0rls bike use. Yokouchi told a reponer thm Ihe ideal SP0rlS bike would be very light with excellem handling. superb brakes and high horsepower outpU! aided by the latest in engine technology. Yokouchi's appoilllmelll as the man in charge of designing machines for America has greal significance for high-performance emhusiasls. according to company insiders. Yokouchi formerly was assistant general manager of Suzuki's Motorcycle Designing Division. When the Division was split several years ago, Yokouchi was named general manager of Division II, in charge of designing machines for japan and Asia. During his (enure Suzuki imroduced the two-stroke Twin RG250 Gamma. a racer-styled machine that became the best-selling 25.0 in japan in 1983. Yokouchi's most recent project was the GSX-R, a japanesemarket aluminum-framed, watercooled 16-valve 400cc Inline Four styled like the 1983 works HB Suzuki endurance bikes. Yokouchi designed the X6 250cc two-stroke Twin Hustler in 1965,the T500Titan 500cctwo-strokeTwin in 1967, and the GT750 water-cooled two-stroke Triple in 1971. In developing the GT750, Yokouchi pioneered the use of aluminum radiators. In 1974 Yokouchi was put in charge of Suzuki's racingeffons, his responsibilities including building worldchampionship-winning machines for Roger DeCoster (500cc motocross), Barry Sheene (500cc road racing), Gaston Rahier (125cc motocross) and Akira Watanabe (125cc motocross). In 1976 Yokouchi's responsibilities expanded to include SlreC! bi ke dcsign. He d ireeled devdopment of tilt' eigh tvalv(' (;5750 and GS 1000. and later the 16-val\'(' (;S 1100 and GS750 with SIIlUki's TSCC (Twin Swirl Combustion Chamber) cylinder heads. Yokouchi was personal1y responsible for the decision to manufacture and sell the futuristic Katana 1000 and 1100 models. Since taking over Division I. Yokouchi has installed Mr. Sadeo Shirasagi as his deputy. Shirasagi did much of the actual design work on theTSCCcylinder head design. taking a theory and IUrning i! illlo functioning paris. Yokouchi is 50 years old and joined Suzuki in 1957. shonly after gradualing from college. He is a personal friend of Pops Yoshimura and is a high-pt'rformance and racing clllhusiasl. Yokouchi says Ihat the rider must feel that the designer made this bike for him. so a designer must develop an understanding of whal a rider walllS. where he'lI be riding. and in what ways he looks to enjoy his moto~cycle.. • " ,.