We just got in a shipment from White Industries, including super cool double singlespeed freewheels (yes, I know it's an oxymoron.)

These are the same thickness as their single freewheels, but with two sets of teeth. The teeth are staggered so that the chainline is not too far off if your chainring is set for a single freewheel.

This gives you the functionality of a flip-flop hub without the need to remove the wheel to change gear.

There are two versions, 16-18 and 17-19. We just received the 17-19 version, 16-18 is not yet in full production, but expected soon. Not cheap at $119.95, but even a regular White Industries freewheel is $90...they're the very best, with sealed cartridge bearings and an unusually fine ratchet mechanism.

One of these is DEFINITELY going on my Rambouillet, it's PERFECT for that application.

http://sheldonbrown.com/harris/white-freewheels.html

Sheldon "TickTickTickTick" Brown
Newtonville, Massachusetts
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| Life is the art of drawing sufficient conclusions |
| from insufficient premises. --Samuel Butler |
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http://sheldonbrown.com/harris/images/white-2sp-doubleh.jpg