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My Bianchi B.a.S.S. fixed-gear mountain bike has been one of my favorites since I built it in 2002. Unfortunately, however, my deteriorating health makes fixed-gear riding pretty much impossible for me, so it had been gathering dust for a few months.
Sram to the rescue! A friend of mine at Sram sent me an early production sample of one of their new iMotion 9-speed internal gear hubs! Now I have the low gears and freewheeling ability my feeble legs need.
This gives a very nice range of gears. I'm running 42/20. My online Gear Calculator shows that this provides the following gears:
That's a bit lower than I would have chosen when my legs were working well, but quite a nice range, with very reasonable gear spacing.
Gain Ratio 7.1 6.2 5.3 4.5 3.8 3.3 2.8 2.4 2.1 Gear Inches 94.8 82.8 70.7 60.2 51.4 43.8 37.4 31.9 27.9 Meters 7.6 6.6 5.7 4.8 4.1 3.5 3.0 2.7 2.2
Unfortunately, at the moment, this hub is only available with a coaster brake, but I really shouldn't look a gift horse in the mouth.
Strangely, the only shifter currently avalable is a twist-grip integrated with a brake lever. The B.a.S.S. already had superb brakes (Shimano LX V brakes with Kool Stop salmon pads) and now with the (quite good) coaster brake, stopping is NEVER a problem!
Versions with different braking options are intended to be introduced in 2007. At present, even the coaster brake model is only available in Europe. It is my hope that when they do become available, we at Harris Cyclery will be among the first to offer them for sale.
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