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77 gs750 main jet selection, check my reasoning

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    77 gs750 main jet selection, check my reasoning

    I am helping a member of this board get his 77 gs750 with vm26's, 4 individual pods and "header" running correctly. per past recommendations (to others) by Keith Krause and recent suggestions by others (thanks TCK). It has been suggested to start with 125 and 127.5 mains. we installed the 125's but until he gets the needed 2.85 shim and the intake boot o-rings we won't know if the 125's are in the ball park.

    I looks like it has emgo pods and some kind of odd ball header, because the No# 2-3-4 cylinders go straight down into the pipe running from the No# 1 cylinder to the muffler. (non equal length pipes).

    The stock main jets should have been 102.5's. but I found it with 107.5 mains installed. likely because of the pipe at one time, but no history of what and when the pipe and pod changes were made. I'm thinking that a 122.5's might be a better choice as a starting point for re-jetting.
    I can't use the existing color of the plugs to get some kind of idea where it was at, because duct tape was wrapped around the pods to richen it up. (mega, black...)

    Yes I know it's hard to guess a starting point, but would you go down a 1/2 step to the 122.5's or stick with the 125's as a starting point?

    TIA, Dale
    Last edited by rustybronco; 04-05-2009, 12:10 PM. Reason: (to others)
    De-stinking Penelope http://thegsresources.com/_forum/sho...d.php?t=179245

    http://www.thegsresources.com/_forum...35#post1625535

    #2
    You got recommendations from Keith Krause and now you are asking us? Dude, you have your priorities backwards.

    From what I remember, for pods and a pipe (by the way, post some pics of that pipe, please), you need to start about six sizes larger than stock.
    If stock was 102.5, I would start at 117.5. Of course, this is just a starting point, who knows where you'll end up.

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      #3
      Originally posted by Steve View Post
      You got recommendations from Keith Krause and now you are asking us? Dude, you have your priorities backwards.

      From what I remember, for pods and a pipe (by the way, post some pics of that pipe, please)
      No, it was just from recommendations that he made to others in the past on re-jetting 77 gs750carbs that were equipped with pods and a header.
      my question is because of the different header, that it might bring the jetting a little more closer to stock, than has previously been suggested. if Keith knew the details and recommended that jetting, he would have no arguments from me. (who am I to question "the" carb guru)

      Pic's will come...
      Last edited by rustybronco; 04-05-2009, 11:19 AM.
      De-stinking Penelope http://thegsresources.com/_forum/sho...d.php?t=179245

      http://www.thegsresources.com/_forum...35#post1625535

      Comment


        #4
        Links to Pictures of header



        Here is a picture of the header on my bike I put more pictures in my album

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