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  1. #1
    Small wheels ARE better! OldiesONfoldies's Avatar
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    Help me w math - downsizing chainring 52 to 42

    Dear folks,

    I've changed the chain ring of my Speed 8 to a smaller one, 52 to 42. Wondering what is the effect on the gear range. Can someone help me calculate the new gear range with this mod? Does this reduce the gearing by 25%? The original cassette 11 -32t remains.

    Speed P8 31-91' (with 52 chain ring)

    42 chain ring = 24 - 69 (is this correct?)

    Hope to do some serious climbing with the new mod. Many thanks!

    OnF

  2. #2
    My legs hurt
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    http://www.sheldonbrown.com/gears/

    This should tell you all you need to know.

  3. #3
    jur
    jur is offline
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    New gear range = old range * new ring / old ring
    = 31-91" * 42 / 52
    = 25-73.5"
    My folding bike photo essays www.dekter.net/

  4. #4
    Small wheels ARE better! OldiesONfoldies's Avatar
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    Thanks guys! Glad for the helpful experts here...

  5. #5
    aka Phil Jungels Wanderer's Avatar
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    You have effectively reduced all the gear ratios by approximately 20%.

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