This oval piston was used by Honda to skirt the regulations of the time which stated that an engine could only have 4 combustion chambers. Thus Honda made elongated bores so that each combustion chamber could be extra large and help in catching up to the power made by the two stroke bikes. The experiment was a failure as 13th place was the highest finish they achieved in GP racing although they did manage to win one heat race at Laguna Seca with Freddy Spencer and the Suzuka 200 kilometer race with Kengo Kiyama.
