Originally Posted by
nashcommguy
There must be something limiting about the type of torque/motion one applies at the cranks for what my friend and I came up with not to have been developed. Apologies to the OP for the thread drift.
A more likely reason that such a system hasn't been developed on a production bicycle is, as Sheldon Brown says, "nothing exceeds like excess." The technology exists (SRAM DualDrive 3x9, quad front rings, Schlumpf dual drive bottom bracket) to create a bicycle with 216 gears. But such a thing is outside the bounds of usefulness, as is Sheldon's tame-by-comparison 63-speed OTB. I think that we reached the level of covering the ground we needed with triple cranks and 7-speed cassettes and freewheels. More than that is certainly nice, but I think that, beyond 21 speeds, everything else is just gravy.