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  1. #1
    Compulsive Bike Builder
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    SRAM ESP vs Shimano Cable Pull

    Which pulls more cable per shift for the rear derailleur: SRAM ESP or Shimano? That is one of the differences between 1:1 and 2:1 shifting.

    I may have a follow up question based on the answer to this.
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  2. #2
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    Sram pulls more cable per shift. A 9 speed cog has a seperation of 4.35mm from the center to center between each cog. Sram ESP pulls 4mm of cable per shift while Shimano pulls 2.5mm per shift. That gives you a ratio of 1.1:1 for Sram and 1.7:1 for Shimano. The misconception that the pull ratios are 1:1 and 2:1 respectively are rounded off numbers by Sram's marketing to make the difference seem more impressive.

  3. #3
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    Great, thanks

    The if that is the case, it is unlikely that a Shimano friction shifter - say 8/9 speed bar cons - will throw enough cable to shift a SRAM ESP type, say an X-9. While you would not have to worry about cable per shift with index, you would not be able to throw the cage all the way across the cassette.

    Without setting it up and trying it, that sounds like the logical conclusion, no?
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  4. #4
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    Quote Originally Posted by DirtDad

    Without setting it up and trying it, that sounds like the logical conclusion, no?
    I would agree this is the most likely possibility.

  5. #5
    Formerly DMR For Life
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    your going to need more cable movement @ the RD to move it one cog with the sram than the shimano....roughly you would have to move the shifter 2 indexs to get the RD to move one cog...and as a result you couldn't get much more than half way across the cassette
    does that sound right?
    DMR

  6. #6
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    Quote Originally Posted by DMR For Life
    your going to need more cable movement @ the RD to move it one cog with the sram than the shimano....roughly you would have to move the shifter 2 indexs to get the RD to move one cog...and as a result you couldn't get much more than half way across the cassette
    does that sound right?
    DMR
    The Sram pulls only 60% more cable than the shimano. That will means an ESP derailleur will move about 7 cogs with 9 clicks on a shimano indexed shifter.

  7. #7
    Formerly DMR For Life
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    yes that right but you would have a significant problems with the RD making noise and such because with one click you wouldn't move the RD enough, but with two you would move it to far but not far enough to get it on to the next cog if you get what i'm getting at
    DMR

  8. #8
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    Quote Originally Posted by DMR For Life
    yes that right but you would have a significant problems with the RD making noise and such because with one click you wouldn't move the RD enough, but with two you would move it to far but not far enough to get it on to the next cog if you get what i'm getting at
    DMR
    Yeah I do. The spacing would be either too short with one throw or too long with two. It just wouldn't line up.

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