I was confused when I first attempted a conversion. There are a few things to deal with, but a conversion kit is not necessary with a freewheel. Performance makes one for freehubs which works well.


steps for freewheel-to-ss conversion:

1) remove freewheel with proper tool (hey, I thought a chainwhip was necessary too!) - a vice works great for a stuck freewheel, because you can twist on the rim to apply torgue. You still need the removal tool though - the vice just replaces a large crescent wrench.

2) buy a BMX (single cog) freewheel. Mine is Shimano ($19 from LBS), and install in place of the Falcon.

3) adjust axle spacers to align the chainline with your front chainring. I used my inner chainring.

4) to center the rear wheel in the frame, re-dish the wheel. I did not do this because of spoke length problems, but my wheel lined up pretty well. I got lucky. Another thing that worked well was a new axle that had adjustable spacers. You just dial in the fit.