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  1. #1
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    Discovering Fixed Gear Ratio's for the Infirm

    At the ripened age of 59 (just) and having discovered the fixed gear road bike, the physical question is of course the gear ratio. After a couple of chain ring changes & cog replacements I have decided that a 39 X 16 feels pretty good. Fast rpm's but at 80 cycles per minute and at @ 20 mph I'm there. At a lower cpm I'm just cruisin. Lucky I'm limber (lucky I'm alive). The idea for such a low ratio is zero physical impact from the neck down...........Gear ratio input would be appreciated and hey, try a fixie.

  2. #2
    Jim Shapiro
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    Quote Originally Posted by particleman
    At the ripened age of 59 (just) and having discovered the fixed gear road bike, the physical question is of course the gear ratio. After a couple of chain ring changes & cog replacements I have decided that a 39 X 16 feels pretty good. Fast rpm's but at 80 cycles per minute and at @ 20 mph I'm there. At a lower cpm I'm just cruisin. Lucky I'm limber (lucky I'm alive). The idea for such a low ratio is zero physical impact from the neck down...........Gear ratio input would be appreciated and hey, try a fixie.
    Welcome to the world of fixed-gear bicycles. I am 64 and a newcomer to fixies, having converted an old Centurion road bike into a fixie a few months ago. I kept the larger, 52 tooth, chainring in front, removing the smaller ring and mounting the bigger one in its place for a perfect alignment with either (fixed or freewheel) rear cog. I bicycle almost daily and don't plan on using this bike for serious climbs (and there are plenty of those around here -- Boulder, Colorado), so I went with a 17 tooth cog on both sides of the flip-flop hub. That's about 84 inches and, with 700 rims and 170 mm cranks, it comes out to a gain ratio of a little over 6, i.e. quite high on both scales. So far I have been very happy with my choice, but climbing hills takes both anticipation and endurance.

    I am not strong or confident (or is it crazy) enough to go brakeless, like the Denver messengers, so the bike still has both brakes. In fact, I swapped out the original brakes for a set of used Shimano 105s and then added a pair of in-line levers that mount on the upper, straight, part of the drop handlebars. These are wonderful and I highly recommend them, as you don't have to keep going into the drops to brake. They're cheap, too.

    Time to bike here. Enjoy.

    Jim
    Last edited by jimshapiro; 03-30-05 at 08:34 PM.

  3. #3
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    Hello........My gain ratio with the 17T cog and 39T chainring is 4.9. (hope I'm right here) My SR originally had a 52 chainring (and a 13 cog......whew!) but noticed that the "usual" messengers ran a 42 X 17. If your climbing "hills" in Colorado you might really think about that 42 up front. As soon as the spring westerlys poop out I'll go back to that 39X13. These fixed gear bikes are great!

  4. #4
    feros ferio John E's Avatar
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    It's too bad Sturmey-Archer stopped making 3-speed fixed gear hubs in the 1950s. It sounds like a very interesting concept, and I know that Jim Cunningham loves his.
    "Early to bed, early to rise. Work like hell, and advertise." -- George Stahlman
    Capo [dschaw'-poe]: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger, S/N 42624
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  5. #5
    cyclist/gearhead/cycli... moxfyre's Avatar
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    Quote Originally Posted by particleman
    At the ripened age of 59 (just) and having discovered the fixed gear road bike, the physical question is of course the gear ratio. After a couple of chain ring changes & cog replacements I have decided that a 39 X 16 feels pretty good. Fast rpm's but at 80 cycles per minute and at @ 20 mph I'm there. At a lower cpm I'm just cruisin. Lucky I'm limber (lucky I'm alive). The idea for such a low ratio is zero physical impact from the neck down...........Gear ratio input would be appreciated and hey, try a fixie.
    Uh, I'm only 23, just reading this cause I saw Fixed Gear in the title.

    I say is if you're running 39x16, you're doing great. I run a 39x15 with 27" wheels and 170 mm cranks, so maybe 10% higher than you. It's by no means an overly soft ratio, even for me being young and in pretty good shape. The trick is to find a ratio that's SLIGHTLY higher than what you would use on flat ground normally. This will make downhills bearable, flat ground will be good exercise, and uphills will (still) be hard.
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  6. #6
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    Now thats pretty interesting and your right. I would have put a 42 chainring on but I couldn't find one in this town. I think that would have been perfect (42 X 16) since this town is as flat as Kansas. I looked for help with the local "velo" club and they all but choked on the words "fixed gear".

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