Ovalized sprockets have made there way into the cycling community. Recently, U.S. Cyclist Bobby Julich used an unusual shaped chain ring to win the bronze medal in the Athens Olympics. For cycling, the odd shaped chain ring is designed to take advantage of the greater power produced in the down stroke of a cyclists pedaling action.
Since the motors in the KOP obviously do not produce different power outputs within one revolution, these ovalized chain rings don't offer any realistic purpose for a FIRST robot, that I can think of anyway.(although I'm sure someone can come up with something wacky...ie pneumatically powered crankshaft
