Yellow color coded for biggest size. Stock replacement for all L77-89 B.T. models. Used as conversion kit on 90-99 Evo B.T. with pre-90 pinion shaft. For 1989 and earlier type pinion shafts used on 90-99 Evo B.T. models (engines that use S&S flywheels or other multiple parts flywheel assemblies) S&S offers this conversion package. Kits include a color coded 77-89 pinion gear, 54-89 oil pump drive gear, 54-89 pinion shaft gear spacer and a 54-89 pinion shaft gear nut. Note see: 531306 Black (smallest), 531308 Blue (average), 904148 Red (average), 531309 Yellow (biggest). Note: All kits must be used with a 73-99 B.T. style oil pump driven gear (S&S 531209 / OEM 26345-73). Note: If the stock gear is unmarked and the size is unknown or you are scratch building an engine and without gear, S&S recommend a gear in the middle of the size range. These sizes were used more often and should provide adequate gear clearance under most circumstances. When in doubt, use a gear from the middle to the small side of the range, because a combination of looser fitting smaller gears will give a harmless clicking sound but to tight can cause a wining sound, binding and premature wear. Consult the factory service manual for information on optimum cam gear to pinion gear fit instructions before you order.
