Originally Posted by
tatfiend
I thought about that before buying my NuVinci hub. Unfortunately the power transfer setup of the NuVinci hub design is one way, not reversable. If you build an older pre N360 version of the hub up w/o the freewheel there is some minor drag on the pedals with the bike moving when not pedalling but not a solid connection like with a FG bike. This info is from a BF member who reported that he tried building a bike with the original hub and w/o the freewheel.
I have a bike with the S3X hub and cannot see any reason the Schlumpf 2 speed drive crankset should not work with it. Be an expensive drivetrain though. I believe that you would want to use the speed drive for the project as IIRC it's step is about the same as the overall range of the S3X so it should give 5 speeds effectively and a overall ratio range of about 250%, similar to a SRAM P5 or new SA 5 wide IGH hub.
The Schlumpf Mountain drive would give broader dynamic range than the Speed Drive.
It might give you too much torque throught he hub, though there were faqs out there from SRAM on how to mate the S7 to the Mountan Drive.
A Schlumpf with track/fixie rear hb could give you a 2 speed as well.
Sheldon Brown acquired an ASC hub in 2005 and mated it to a Schlumpf to give him a 6 speed.