I might have missed something, but I am not aware of any of the carburated twins having catalitic converters. No cats (or katz as we spell it) to factor in.

05 speedmaster - 1100cc, 11:1 racing pistons, Carillo rods, thunderbike cams, ported and polished head, 2mm over intake and exhaust valves, Barnett kevlar clutch, scepter pipes, oversize manifolds, 45mm HSR's, TTP stage 4 firestarter