Quote Originally Posted by Kuma View Post
so this is what I was thinking and using a bearing housing like a standard spool setup, but now how do I mount a sprocket?
You'd have to have the main part machined - remove the gear and put some holes in it to mount a sprocket up to.

Actually, what I'd probably do is machine the gear off (that's gonna be tough - guarantee that's some hard stuff) and then make an adapter that uses the holes as drives - you could make it a cush drive and absorb shock. Source some sort of o-ring (big, thick, stiff) or similar.

Anyhow, it would be two pieces - Chain sprocket adapter side - would have a step for centering the sprocket and lugs for mounting bolts (just like it does on a bike) on one side and then lugs that would go through the windows on that piece and be the cush drive. The pins would go .100" proud of the assembly.
The second piece would be a round plate and have pockets that the proud pins would fit into. Bolts would go through the second piece and thread into the pins on the first piece. Pretty simple, actually. Make it so it has .005-.010" of slop in the same axis as the tube section so the adapter can float (cush) but not twist out of alignment.

Probably have to get a custom sprocket but those are fairly easy to come by. I think Super-Sprox does custom stuff and they're damned near bulletproof - they wear very, very well. If you could get one with a small ID that would make the adapter better and smaller.