what size Accelerator Pump carb

Discussion in 'Ask the Tech Masters???' started by stretch, May 31, 2019.

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  1. May 31, 2019 #1

    stretch

    stretch

    stretch

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    I am considering a swap to a carb with an accelerator pump on a stock 125.
    would those of you with more experience recommend a 27mm or 30mm carb?
     
  2. May 31, 2019 #2

    stretch

    stretch

    stretch

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    or would both be too large for a stock 125?
     
  3. Oct 19, 2019 #3

    Cactus Jack

    Cactus Jack

    Cactus Jack

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    It depends on if the carb has a round or oval bore ... Oval bore carbs are smaller in flow than their outlet bore so a "30" Mikuni for instance is actually a 26 mm carb... You add the height and width of the venturi at the slide together then divide by 2 to get the actual carb size ... Round bore carbs are the actual size of the round bore ...
    Your inlet port size is what you should measure ... A "27" oval bore carb or a 26 mm round bore carb will work great with a 26 mm intake port and 27 mm inlet valve ...
     

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