NuVinci Hub as Jackshaft, how to calculate reduction?

LI-ghtcycle

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Staton Inc. has me thinking ... here they have a nice set-up to allow the hud as a jack-shaft with a 44T single speed chain sprocket on the outside of the hub:

http://www.staton-inc.com/store/pro..._N171B_350_Mid_Drive_Silver_Black-542-20.html

3252.jpg


So, I was thinking, given that this older hub the N171B does not have an internal freewheel, how hard would it be to say make a 80T or higher in #25 chain on rim mounted cog/chain ring that was run by a high RPM motor, such as a RC and effectively reduce it down to a point in that first single stage reduction that it could make for a useful 1:1 ratio speed (say 30 MPH for instance)?

Now you would be running the NuVinci in reverse, so instead of a 0.5 underdrive and 1.75 over-drive, you would have the reverse, so more lower gearing (which makes more sense to me anyway) and the only difficulty I would see is the cog/freewheel that you would have on the threaded FW adapter would be trying to un-screw, but if your using it as a jack-shaft, you wouldn't want a freewheel anyway since this would be on the wheel with the final drive.

I guess the first question would be to ask Fallbrook Tech if the NuVinci would work going in reverse (and I guess you would need to use it as a LH drive too with maybe a flip-flop track hub for the rear wheel, or use the disc brake mounts on the hub) or just employ something similar to what Rassy did to reverse the chain's direction and keep everything on the RH side.

Maybe I am just over-complicating things, and it would work just as well or better to keep the NuVinci in the rear wheel and just use a #25 sprocket as the motor driven sprocket and dual RH side drive but with a high RPM R/C motor.

Just a crazy thought I had ... don't worry I'm not abandoning my current build in anyway, just a random thought .... :wink:
 
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