Calculating sprocket sizes

Discussion in 'OT Driven' started by DamonS, Sep 25, 2005.

  1. DamonS

    DamonS Flyin' High Again

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    I have done a bit of research on this (read: google :) ) and still don't have a "general" enough answer to answer this question. Everything so far has been far too technical or I need to know hp, gear ratios, etc.

    So, I come here looking for some "rules of thumb".

    OK.. I have a Suzuki Quad Sport and am due for sprockets. Currently it is running 12 tooth front and 41 tooth rear. All of the aftermarket places "recommend" 11 tooth front and 39 tooth rear, to the end that they don't even stock the OE tooth arrangements.

    Why would this be? What will this gain me? From my calculations thus far, I will be losing on the top end by about 5-6 miles per hour (not a big deal, since I mainly trail ride), but what is this going to do to my bottom end? Will I gain a bit of torque? Will I have to rev higher to get the same performance? Will I run out of gear trying to keep up with my son (right now its pretty close)?

    I can go to the dealer and pay double the price for the OE sprockets, but if I the change is going to be barely noticable, then what is the point.

    Some rules of thumb on changing 1 or both sprockets to the smaller size would be extremely helpful to me.

    Thanks in advance
     
  2. ecofire

    ecofire Member

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    I've never heard of someone shrinking both sprockets. Usually people shrink the front one and raise the rear one to get more low power. I guess thats what might happen from shrinking them both, but I can't really, seem pointless to me to go down in both directions.
     
  3. z31maniac

    z31maniac *insert witty remark*

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    Going down in both directions is equivalent to just going up on the rear or going down on the front, by a smaller margin.

    The rule of thumb for bikes is -1 on the front = +3 on the rear.

    SO if that holds true for quads as well, it looks as though the combo they are suggesting, would be the same as going +1 on the rear, which really isn't that big of a change, just a few %.
     
  4. dhacmbs

    dhacmbs OT Supporter

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    i think this will help
     
  5. Jujharoo

    Jujharoo New Member

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    going down on both sprockets doesnt make sense. you might as well go 2 up in the back instead of going -1,-2
     

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