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    #16
    A quick tip to rule out any leaks at the intake boots and even the inlet valves if needed.
    With the carbs off , spin the motor for a second or so and place the palm of you hand over the intake as you do this.
    You will feel suction and as you do this momentarily release the starter and pull you hand away.
    You will hear a pop and also feel the amount of suction.
    Do this a few times across the cylinders in fairly quick succession and once you have the knack you be able to differentiate both audibly and by feel if one or more is not holding the depression or not pulling like the rest.
    Finally delay pulling your hand off each inlet and you will feel how quickly each one loses suction and it will be obvious if one is normalising quicker than the rest.
    This test puts way more suction on the boot joint etc than would ever be seen in normal use and if you can't detect a significant difference between them doing this there is no way there is a leak there under normal running conditions.

    Also a static test for the diaphragms and carb top leaks.
    Simply fully lift two slides at a time with your index and middle finger and let them drop.
    Observe the speed at which they both close which should be at equal rates, smooth and damped.
    Do this across all four to compare all equally.
    If one falls rapidly or snaps shut you have a diaphragm split or leaking carb top etc.
    If one falls much slower ( which is what you are really looking for ) then you possibly have some slide stiction or some other issue such as a bent jet needle binding in the jet etc.
    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



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      #17
      Nice! I like performing tests more than inspecting. I just gotta ask before I do this, would compression play a factor in this? Pretty sure all my cylinders are good so I shouldn't have to worry but I'm just curious. Need to buy a compression tester at some point.

      At this point I'd pay somebody on here to come and help me figure out what's going on, wish more people were in florida! I know it's all simple stuff but man, once you basically have worked on every section of the bike and you're still having issues, it hits you a bit.
      Ian

      1982 GS650GLZ
      1982 XS650

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        #18
        If you have a really bad cylinder it will show but we are talking a very significant compression drop caused by severe exhaust valve leak or damaged bore to affect the suction test when spinning on the starter.
        With the comp test around 15psi difference between the highest and lowest readings is acceptable on the average modest compression of a road motor.
        Surely there's someone nearby who could have a look..
        Maybe putting feelers out on the forum may get some response from someone local.
        A couple of hours or so is all it should take to find the problem.
        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



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          #19
          Originally posted by zed1015 View Post
          If you have a really bad cylinder it will show but we are talking a very significant compression drop caused by severe exhaust valve leak or damaged bore to affect the suction test when spinning on the starter.
          With the comp test around 15psi difference between the highest and lowest readings is acceptable on the average modest compression of a road motor.
          Surely there's someone nearby who could have a look..
          Maybe putting feelers out on the forum may get some response from someone local.
          A couple of hours or so is all it should take to find the problem.
          Okay cool will probably be doing it tonight, if I cant seem to find anything out of the ordinary I might very well make a post asking if anyone could come by and help out. Not to mention the great roads there is here to ride.
          Ian

          1982 GS650GLZ
          1982 XS650

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            #20
            You've gotten some good advice from Zed. When you do the spray test, along with the intake boots , spray the carb bodies as well. Especially around where the throttle shaft goes through the body. They can get worn and can be sucking air through there.

            Mad
            83 GS750E
            2006 ZX14
            2004 KTM 450 EXC
            2001 Yamaha Big Bear

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              #21
              Originally posted by cowboyup3371 View Post
              I’d get new boots as they should all just jump onto the carbs equally at the same time. You should also consider getting new clamps
              I agree, cuz this is most likely culprit. Spring for the oem’s or try a cheap set of 4 (maybe $25 including clamps) to eliminate boots/ clamps as issue.
              1981 gs650L

              "We are all born ignorant, but you have to work hard to stay stupid" Ben Franklin

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                #22
                Heres the intake boot test

                And the slide test


                Please give opinions as to what yall think before I go big baller and buy things I dont need.
                Ian

                1982 GS650GLZ
                1982 XS650

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                  #23
                  Butterfly valve/throttle rack reaction
                  Ian

                  1982 GS650GLZ
                  1982 XS650

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                    #24
                    Ended up going big baller and getting new intake boots aswell as the airbox boots and then some, if this isnt the issue well that's what my tax return is for
                    Ian

                    1982 GS650GLZ
                    1982 XS650

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                      #25
                      Have not seen anyone mention the “0” rings under the pilot screws, if one or more go bad you can get the problem that you have.

                      V
                      Gustov
                      80 GS 1100 LT, 83 1100 G "Scruffy"
                      81 GS 1000 G
                      79 GS 850 G
                      81 GS 850 L
                      83 GS 550 ES, 85 GS 550 ES
                      80 GS 550 L
                      86 450 Rebel, 70CL 70, Yamaha TTR125
                      2002 Honda 919
                      2004 Ural Gear up

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                        #26
                        Originally posted by gustovh View Post
                        Have not seen anyone mention the “0” rings under the pilot screws, if one or more go bad you can get the problem that you have.

                        V
                        Will replace those aswell luckily have a o-ring kit here
                        Ian

                        1982 GS650GLZ
                        1982 XS650

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