Lend me your brains

I actually thought about this, but I have a couple of other fairly simple ideas to fix the pedal against unscrewing.

People ride differing chain ring/cog set ups all the time, they just adjust the chain length to fit.

I mean, when I flip my wheel over to use a different sprocket, I slide the axle forward in the dropouts.

There's an article on 63xc.com about choosing "magic gears" and you'd have to do something like that to make sure both your ratios will be compatible. But, as I said, I'm sure you've already done this so I'll shut up.

http://www.63xc.com/toddp/halflink.htm