2. to actually build and two speed tranny that would fit would be a humongous task. Have you looked at the xmod chassis? its quite cramped.
3. someone brought up the point that since a bit or bit clone has two speeds why cant an xmod? to answer that question the bits "second speed" is done with electronics not mechanical parts. All is does is boost the power to the motor. The xmod already has this in its hi lo switch.