Announcement

Collapse
No announcement yet.

GS550 VM carb mid pilot jet size

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    GS550 VM carb mid pilot jet size

    Hi guys

    I would like to know how important the size of the mid pilot jet (air jet) is?
    The thing is I cant find the correct size 50 pilot (air) jets. All I can find is 160’s.
    My bike has pod filters, because I cant seem to find a complete stock airbox.
    The weird thing is how rich the bike is running with these pods.
    Main jets are stock 80’s and pilot jets are 15’s.
    Needles are set at stock clip position.
    I had to completely close the fuel screws at the bottom of the carbs just to be able to lean the idle out using a colortune plug.

    Any ideas or advise would be appreciated
    sigpic 1980 GS550E

    #2
    By your setup description you should be running very lean, maybe your float valves are not closing... have you cleaned the carbs to forum specs?
    -Mal

    "The only reason for time is so that everything doesn't happen at once." - B. Banzai
    ___________

    78 GS750E

    Comment


      #3
      What make pods are they?
      Cheap pods are well known for being restrictive or masking the air bleeds in the mouth of the carb causing rich running and power loss and this is most likely your problem.
      You get what you pay for and should only use well known free flowing proven brands such as K&N, APE, PIPER, UNIFILTER etc.
      Once you have an unrestricted inake you should fit air corrector jets to cure the off idle hesitation/flat spot and only increase the main jet size while leaving all other jets and needle position stock.
      Mikuni Viton Choke Plunger Seat Renewal.
      VITON Choke plunger seals .KAWASAKI Z1,Z900,Z650,Z1000,Z1R,SUZUKI GS1000,GSXR,RF | eBay

      Air Corrector Jets for Mikuni VM 24, 26 and 28mm carbs .
      https://www.ebay.co.uk/itm/254380193...84.m1555.l2649



      sigpic

      Comment


        #4
        Carbs were cleaned to forum spec. Dipped, ultrasonic and new o-rings etc.
        Yes the pods are no-names.
        I will replace them with proper pods.
        If I were to run without pods, my bike should be really lean? Just as a test?
        I will report back.
        Thank you
        sigpic 1980 GS550E

        Comment


          #5
          What exactly does the mid jet (50) do considering there is another pilot jet (15) just above?
          sigpic 1980 GS550E

          Comment


            #6
            Originally posted by Vloukole View Post
            Yes the pods are no-names.
            I will replace them with proper pods.
            If I were to run without pods, my bike should be really lean? Just as a test?
            I will report back.
            Thank you
            Yes! if stock jetting it will run lean without the airbox.
            Quality pods should flow as much or almost as much as running open carbs or velocity stacks and offer little or no restriction.




            Mikuni Viton Choke Plunger Seat Renewal.
            VITON Choke plunger seals .KAWASAKI Z1,Z900,Z650,Z1000,Z1R,SUZUKI GS1000,GSXR,RF | eBay

            Air Corrector Jets for Mikuni VM 24, 26 and 28mm carbs .
            https://www.ebay.co.uk/itm/254380193...84.m1555.l2649



            sigpic

            Comment


              #7
              Originally posted by Vloukole View Post
              What exactly does the mid jet (50) do considering there is another pilot jet (15) just above?
              Any idea/info regarding this?

              sigpic 1980 GS550E

              Comment


                #8
                I ran my bike with no filter. Just around the block. The bike still bogs down and plugs are black/sooty.
                It bogs at half throttle and up.
                How is this possible with stock jets and needle position.
                Idle to 1/4 throttle is fine. I used a color tune to tune the idle.
                Fuel screws are at 1/2 a turn and air screws are between 1 1/2 and 2 turn out.
                Could it be the emulsion tube o-rings that are leaking? They are all new.
                Float height is set at 26mm.
                sigpic 1980 GS550E

                Comment

                Working...
                X