Trying to Break the Domination of the Yamaha TZ750
Paul Schwab photo
In this week’s Throwback, we dial in March 9, 1980 into our time machine and set the destination to Daytona International Speedway. Much like American Flat Track and it’s Indian FTR750 problem, in the late 1970s, AMA National Road Racing was dominated by a single machine, the awesomely powerful Yamaha TZ750 two-stroke. Going into the 1980 season nothing other than a Yamaha two-stroke TZ750 or TZ500 had won an AMA National Road Race since 1974! The AMA finally resolved to try to level the playing field for the 1980 season by adjusting the rules. That year the AMA restricted the 750cc two-strokes with a 23mm intake, left 500cc two-strokes unrestricted and allowed four-strokes to run up to 1025cc displacement. With that Honda, Suzuki and Kawasaki all developed four-stroke AMA Formula One machines, including the Yoshimura Suzuki pictured here, ridden by David Aldana. This shot shows Aldana (No. 109) passing the Cotton ridden by England’s Derek Huxley (No. 306). Aldana proved the potential of the new 1025cc four-strokes in the Daytona 200. He rode a fast and consistent race and finished sixth (behind five Yamaha TZs). Several scorecards even had him in second at the end of the race, including his team’s. Aldana filed a protest on the scoring, but did not win. Still, the potential of the big four-strokes was clear to see, and the AMA’s new formula did go a long way in leveling the playing field. In the very next AMA F1 round Wes Cooley piloted a Suzuki GS100-based Yoshimura Suzuki to victory at Road America, marking the first AMA National Road Race win by a four-stroke in eight years. This coming Saturday will mark the 80th running of the iconic Daytona 200.
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