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Sheldon Brown's Raleigh Twenty 8-speed

Sheldon Brown's Raleigh Twenty Sturmey-Archer 8-speed
I've owned this bike for quite a while, originally set up as a fixed-gear. Due to some health problems I'm no longer as good at fixed gear riding as I was, and when I had the opportunity to try out the new Sturmey-Archer XRF-8 8-speed internal gear hub this seemed like a perfect candidate for the conversion.

The frame was originally built for a Sturmey-Archer hub, so the width of the dropout slots and the frame spacing made the Sturmey-Archer hub the best candidate.

Another advantage of the Sturmey-Archer 8-speed is the unusual gearing it offers. The bottom gear is direct drive, all of the other gears are "step-up" gears. This makes this hub especially well suited for bikes with small wheels. I'm running it with a 48/25 ratio, giving the following gearing:

Gain Ratios:2.83.54.04.55.15.86.68.4
Gear Inches:36465259687585109
Meters:2.93.74.24.75.366.88.8
The hub uses a twist grip shifter, but it rotates in the opposite direction of the one supplied for the Shimano 8-speed hub as used on my Raleigh International and IRO, so I mounted it on the left side of the handlebar to reduce confusion.

The gear spacing is a bit unusual on this hub. Most of the jumps are in the 13% range, but the top and bottom jumps are 28%.

The big jump at the bottom is actually quite welcome (see "Gear Theory") but the big jump at the top is a bit much for use on the flats. That's one of the reasons I chose to gear the bike as high as I did: the top gear is basically only for fast descents, and this way I have a smoother set of ratios for cruising on the flats.

Since I no longer have the fixed gear as a backup "braking" system I had to install a rear brake. I did one of my home made "drop bolts" with a Shimano dual-pivot caliper, resulting in an extremely powerful brake.

The DiaCompe Tech 77 brake levers work well with this, and also with the Tektro Mini-V in front. A great feature of the Tech 77 levers is that they include a "stopper" button that lets them act as a "parking brake" so the bike won't fall over if I lean it against a wall or a pole.

raleigh-twenty-8-01 raleigh-twenty-8-02 raleigh-twenty-8-03 raleigh-twenty-8-04
raleigh-twenty-8-05 raleigh-twenty-8-06 raleigh-twenty-8-07 raleigh-twenty-8-08
raleigh-twenty-8-09 raleigh-twenty-8-10 raleigh-twenty-8-11 raleigh-twenty-8-12
raleigh-twenty-8-13 raleigh-twenty-8-14    

The photos were made with my new Kodak V570 camera, Photoshop CS 9.0

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March 5, 2006
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