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Thread: Cog ratios

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    Junior Member velo86's Avatar
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    Cog ratios

    Hi, I'm fairly new to riding fixed so would appreciate some guidance...

    I'm currently riding with a 45 tooth crank and 17 tooth cog - a ratio which is really good for me.

    I've just acquired a 51 tooth crank and was wondering roughly what sized cog to use which will be similar to the ratio i;ve got at the moment.

    Any advice would be appreciated.
    Thanks!

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    Member moonraker's Avatar
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    http://software.bareknucklebrigade.c...it.applet.html
    ^Go there and start plugging stuff in. I don't know your crank arm lengths or tire/wheel size, but once you plug everything in it'll give you a list of equivalent gears.

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    dsh
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    twenty

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    i really use a 21.

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    all-weather commuter
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    Middle school math.

    45/17 = 51/x

    (45/17)/51 = 1/x

    51/(45/17) = x

    x = 19.26666

    19 is a bit taller, 20 a bit more lower.

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    Fresh Garbage hairnet's Avatar
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    Quote Originally Posted by RobertFrapples View Post
    45/17 = 51/x

    (45/17)/51 = 1/x

    51/(45/17) = x

    x = 19.26666

    19 is a bit taller, 20 a bit more lower.
    Maths be gone!
    Quote Originally Posted by Scrodzilla View Post
    I'd rather ride a greasy bowling ball than one of those things.
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    Junior Member velo86's Avatar
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    thanks for the help - i'm now sorted!

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