Can't find anything on Google because I guess I don't know what search terms to use.
I am wondering if anyone has ever seen a derailleur setup like I have drawn in the picture. It is NOT for installation on a normal bicycle, but a normal derailleur takes up too much room below the gears and will not work for what I want to do.
(Using a small wheel in larger frame - I have lost all but 4" from gears to ground.)
Please advise on this 'central sprung gear' idea - if you've seen it, if it would work, etc.)
OH_ That three-gear center assembly would slide back and forth sideways on shafts to allow chain alignment.