Abstract: The present invention discloses a two-speed bicycle transmission that utilizes a backward pedaling power input mode to provide a higher forward driving speed ratio (“lower gear”) inherently, without the intervention of any other means of rider control. Such bicycle transmissions were popular in the early part of the 20th Century and marketed as “Retro-Direct.” Since, bicycle transmissions offering even greater numbers of selectable forward pedaling mode speeds have been developed, but at the expense of complexity and reliability, thereby causing a growing fraction of the cycling public to prefer single-speed bicycles for reasons of lower maintenance and/or minimalist aesthetics. Accordingly, the focus of the present invention is to provide a useful second speed with a minimum of added complexity by adapting a uniquely configured and functionally improved Retro-Direct transmission to the modern bicycle. Additionally, a beneficial backward pedaling exercise mode is reintroduced.