Copyright 2003, Roadracing World Publishing, Inc.

AMA Pro Racing Tech officials say they used a dyno to check what effect a lighter oil pressure relief valve spring had on horsepower, before penalizing Road Atlanta Supersport winner Ben Spies and ordering additional teardowns at Pikes Peak.

The dyno check, performed between the Road Atlanta and Pikes Peak AMA Nationals, showed that simply installing the lighter spring confiscated from Spies’ bike increased horsepower on an otherwise unchanged GSX-R600 by 3.0 bhp, according to AMA Pro Racing sources.

Armed with that information, AMA Pro Racing officials said they decided to tear down another nine front-running machines following Supersport qualifying at Pikes Peak.

Three more machines–Hondas ridden by Miguel Duhamel, Jake Zemke and Marty Craggill–were found to have lighter-than-stock oil pressure relief valve springs. All three riders were fined points and cash; Duhamel and Zemke were also moved to the back of the Supersport starting grid and Craggill, who also had a non-standard charging system, was disqualified from competing.

Duhamel elected not to start the race. Zemke charged through the pack to finish seventh.