Originally Posted by
Toeslider
Here's something to mess with your mind:
If you take an Autobike and replace the crankset with one from a normal bike (as mentioned, the Autobike has a freewheeling front crank), would you end up with a six-speed fixie? You could have all the fun of being forced to pedal all the time, without being restricted to a single speed! I think the market value of my Autobike just went up tenfold. A rolling oxymoron...multi-speed fixed gear bike.
I think your line of reasoning is correct, however, there would need to be some kind of screw installed to prevent the gear cluster from unscrewing itself from the hub.
The other problem would be chain tension; when back-pedalling, the chain would be pulled tight on the bottom, and the "dummy" deraileur would be pulled forward, and the slack would then be on the top part of the chain, .
So, really the answer is NO, it can't be done.