Four-Speed transmissions have been built since 1936 in several versions. They were included on bikes with Knuckle engines, Pans, Shovels and some 1984 and 1985 Evolution 80's. With Andrews four-speeds gears, transmissions last longer, shift faster and just plain run better.
This ratio works best on E glides and heavier bikes with motor or transmission sprockets having more teeth than stock sprockets. Installation in 80-84 FX requires 21 tooth (1.82 ratio) second gear for this first gear (16 tooth and 20 tooth on cluster; 24 tooth on counter gear).