Great question - not sure, I'm not a Honda fan through and through to know details like that. Another reader maybe? This was all I could find on the RS series:First seen in 1976 displacing 941cc, the new twin cam, four valves per head, across the frame four utilised gear driven cams, enabling the easy incorporation of an alternator when needed. The works machines, coded RCB quickly rose in capacity with 997 and subsequently 998cc displacements being introduced and dominated endurance racing for the rest of the decade and the early part of the eighties. This machine was prepared for the 1979 Suzuka 8 Hour race, arguably the single most important event for the Japanese manufacturers, for Australian riders Tony Hatton and Michael Cole.The RSC Honda factory engine displaces 1062cc resulting from a bore and stroke of 79mm x 69mm coupled to a six speed gearbox. The original RS1000 crankcases and cylinder are fitted with a "works kit" cylinder head and the machine is adorned with numerous RCB (pure factory) parts including a dry clutch and special ignition system. The RS frame benefits from uprated RCB shock absorbers, a special factory swinging arm, and RCB front forks and front brakes of exactly the same type employed at the Bold'Or by the Fontan/Luc and Leon/Chemaria machines. The seat and tank unit fitted are unique to the machine, being of a different design to those employed by the other RCB's fielded that year.