1993 XR79 Suzuki RGV500
With Phil Aynsley
This is one of the two Suzuki RGV500 XR79 machines built for Kevin Schwantz (Alex Barros received the other two) for the 1993 season. Kevin won the championship with four wins and seven other podiums, while Barros finished sixth with one win and another podium.
Compared to the previous year’s XR78 that Schwantz and Doug Chandler had finished the season in third and fourth places on, the XR79 benefited from improvements to the power delivery, grip, suspension and overall balance. Newly acquired race engineer (ex-Kawasaki and Honda) Stuart Shenton played a major role in the bike’s development.
The 70º V4 big-bang motor produced more than 165 hp at 12,800 rpm and propelled the 130 kg (no fuel) bike to a top speed of over 324 km/h. Two different engine specifications were used at the beginning of the year, one more hard edged, the other more linear in power delivery, with both having the same peak output. The latter type was used by both riders by the end of the season.
To increase traction the pre-progammable ignition timing could be retarded in the lower three gears, according to throttle position and rpm. Additionally both power valves and Power Chamber variable exhaust system were used. A power shifter was also employed for the first time on a Suzuki.
The four 36mm Mikuni carburettors were fitted with two electronic power jets rather than the normal single jet. The second jet supplied additional fuel from over 10,000rpm. A major change to the engine for ’93 was casting the crankcases in magnesium instead of aluminium which saved 2kg.
Suzuki’s next RGV500, the 1994 XR84, can be seen here:
1994 Suzuki RGV500 XR84 | Kevin Schwantz (link).
Source: MCNews.com.au