Originally Posted by
FiftySix
Otherwise, look into 2 speed kickback hubs from Sturmey Archer. Their 2-speed hubs don't require cables to shift, but you do have to backpedal to shift. Pick a 1/8" rear sprocket to go with it.
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I have a 2 speed Sturmey S2 hub and like it very much. It's not automatic but requires a slight backpedal to shift. It takes a few days to teach your muscles to remember just how much to back pedal (the angle depends on your gearing) and, also, you need to develop a strategy for being in the right gear when stopping and starting. It doesn't take long to become adept, though.