Letter From Japan

LETTER FROM Japan

The Sound of Singles grows louder

In Japan, one of the hottest classes in all of roadracing is the Sound of Singles class. It's hot in terms of the competition, and in the kinds of machines the riders build. So it's not surprising that the single-cylinder racing scene has provided some interesting—if not oddball-machines, usually based on Yamaha SR500 or SRX600 engines.

Among the strange machines to show up has been an SR500-based special fielded by the curiously named 499 Squadron team. Weighing in at under 220 pounds dry, the bike is a featherweight. The cleverly built minimalist chassisemploying a chrome-moly steel tubular top half and alloy engine plates in a design based on the Italian Segale superbike chas-

sis—is the biggest reason for the lack of poundage. The box-section swingarm pivots on the engine plates, activating a single, vertically positioned Marzocchi shock through a rising-rate linkage. The SR500 engine has been fitted with a competition cam and oversize valves, as well as a dry-sump oil tank under the crankcase. Claimed power is 48 bhp at 8000 rpm with the specially made exhaust and 40mm Dell’Orto carb.

This bike has been competitive from the start, finishing second to the works-backed Team Ishii Yamaha SRX-R in the last round of the Sound of Singles championship at Tsukuba in October.

The rites of spring

dust like the first robin and the swallows’ return to Capistrano are sure signs of spring, new Japanese 250cc sportbikes signal the changes in model lineups. That’s because the 250s are the first to show the fruits of the latest research and design, with the rest of the models soon following suit. And now that the new GSX-R250 is out, sources are pointing to it as an indication of how the new 750 and 600 GSX-Rs will look.

Styling-wise, the 250 has more-complete bodywork that now surrounds 90 percent of the engine and wraps around most of the frame. Both the remodeled 750 and the all-new 600 GSXR should be here in the U.S. by the end of the year. The 250, however, will stay in Japan.

Kengo Yagawa