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The idea for this came out of a dirt session with one of my mountain bike friends. We were just screwing around doing some technical stuff on a table top. I noticed that his hub (A king) had a tough time handling me pedaling backward faster than the hub was rolling backward (as I was riding fakie) this was due to internal friction (as is present in any hub), but, more prevalently, the friction in the derailer having the chain at an angle. I set about trying to design a way to fit a normal MTN cassette on a freecoaster. I came up with a few designs, but for the most part, they ended just being too much work with out enough quality control (as they would require welding). I then remembered the JB coaster to freewheel conversion...
So here it is:
- Shimano Coaster-brake hub.
- JB Freewheel driver
- Sun-Race 8-speed freewheel (there are no 9-speed freewheels, and this uses a different spline interface than the standard cassette, so I could not just swap it out). I glued it together, to prevent it from freewheeling, with crazy glue.
- Random spacers and such to make the stock axle just long enough to bolt up to a 135 mm spaced rear triangle I could not get a long enough axle because the hardware was 24 tpi, but new axles are 26 tpi.
- Laced to a super cheap Alex 36 hole 26” rim with 15g DB spokes on the non-drive, and 14g DB on the drive (alloy nipples of course).
 
After testing it around the shop, I noticed that it did work well. There was one drawback through, because the hub has a lot of resistance in the clutch, I could not pedal backward without the derailer getting all tangled up. This was, of course, what sparked the initial idea for this hub. But, in the end, I was able to very smoothly roll backward without pedaling. The next step is to convert a more performance oriented hub to make the whole system work very well.
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