Originally Posted by
cycle_maven
A home-brew "dual drive" isn't too hard. Take a couple of sprockets and a spacer from a 7-speed cassette and find an older Sturmey-Archer 3-speed hub. Grind away all but three tabs on the sprockets so they'll fit on the hub. The hub is just wide enough for two sprockets, and the diameter of the hole in the sprocket is the same as the diameter of the hub body. Get a second-hand derailleur from the local co-op, or use the positron. Build the hub into the wheel, cable it up and go- 6 speeds with good ratios. Here's mine:
Great job you did there but I am not sure I would suggest a newbee do this when that person is also trusting that bike as the only transportation. This I would maybe try on bike number two or three..