Measuring Carb Jets

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • jhillier449
    • Mar 2026

    #1

    Measuring Carb Jets

    Sorry if this question has been asked, I did do some searching.

    How do you determine jet sizes for BS34SS carbs? I bought a spare set from Ebay and the seller said it was from a 82 or 83 GS1100E. I have a 1980 GS1000G. I suspect according to the carb specs that the jets are different.

    So

    1. How do you measure carb jet size?

    2. Can I use the carbs from the 1100 as is?

    Cheers

    John
  • hampshirehog
    Forum LongTimer
    Past Site Supporter
    • Oct 2007
    • 12675
    • Hampshire. UK

    #2
    John, the jet size is stamped in to the brass jets in tiny numbers - a magnifying glass is useful if your eyes are like mine.

    The carbs may swap over exactly though I'm not sure - do a search for the carb standard spec sticky on here and that will have the jet sizes etc.
    79 GS1000S
    79 GS1000S (another one)
    80 GSX750
    80 GS550
    80 CB650 cafe racer
    75 PC50 - the one with OHV and pedals...
    75 TS100 - being ridden (suicidally) by my father

    Comment

    • Guest

      #3
      The main air jet on a 16 valve and 8 valve are dfferent. The main jet will not be stock as a result. I'd do plug chops and read the plugs to jet.

      Comment

      • jhillier449

        #4
        Thanks for the replies. I am in the process of rebuilding those 1100 carbs now using the rebuild guide from Bikecliff's site and O rings from cycleorings. I will do what chef recommends, the carb you sent was great for learning on by the way. I think I will offer it to anyone who wants it to practice on if they want to pay shipping.

        Cheers.

        Comment

        • Guest

          #5
          Originally posted by jhillier449
          Thanks for the replies. I am in the process of rebuilding those 1100 carbs now using the rebuild guide from Bikecliff's site and O rings from cycleorings. I will do what chef recommends, the carb you sent was great for learning on by the way. I think I will offer it to anyone who wants it to practice on if they want to pay shipping.

          Cheers.
          Shoot, I didn't even see who you are.
          I'm glad it worked out for you. As I said I never put a carb together with junk parts before.

          Comment

          • jhillier449

            #6
            Junk parts or not, it gives you a chance to see how things are put together without causing causing yourself any grief. If you find out its over your head, then you are not left with a disassembled carb and a red face at your local motorcycle repair shop.

            Comment

            Working...