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    Hey I took my carbs apart today for a cleaning. Inside the bowl there is one jet (I think) that has a screw holding it in with a brace. I can't get that damn thing out! The jet not the screw. I even tried pliers and nothing seems to work! I have another set of carbs that I may put in to replace these but I wanted to know if there was a tip to get that piece out. Also I need to know how long I should soak them in the carb cleaner....Is an hour long enough or should I do it for 24? I only have a paint sized can so I can only do one carb at a time any input would be appreciated.
    Thanks
    Greg
    XS1100 Midnight Special

    "It is better to close your mouth and be thought a fool than to open it and prove them right." ~unknown

  • #2
    I remembered what the part is that I can't seem to remove. The little jet with the screen on the bottom any one know where I can get replacements for those I need them fast Biketoberfest is at the end of this week!!!
    Thanks
    Greg
    XS1100 Midnight Special

    "It is better to close your mouth and be thought a fool than to open it and prove them right." ~unknown

    Comment


    • #3
      The jet with the screen on it, as you refered to it, is actually the float needle and seat assembly. It is sealed to the carb body by an o ring. The ring can get stuck, and it will be hard to get out, without distorting/destroying the brass seat itself. One trick that has worked for me is to spray around the brass with some penetrant, and locate a drill bit that the shank will just fit into the seat. Install the shank as deep as you can into the seat. This will allow you to get a good bite on the seat with a pair of pliers, without distorting it, and twist and pull on the seat until it comes out. It will eventually come out. You will need to replace the O rings, though. You can find them on ebay, Mikes xs, and probably most of the bike parts places online.

      Comment


      • #4
        Ok...So I got everything apart including the carb body soaked the carbs in cleaner cleaned everything with spray cleaner and the bike is running like a champ but it won't idle...I am unsure as to depth on the idle screws but all the little orings and washers are there can anyone tell me how deep I need to go with my idle screws to get optimal idle? I need this Info ASAP please!! Biketoberfest is already here and I want to get this bad boy back on the road!!
        Thanks
        Greg
        XS1100 Midnight Special

        "It is better to close your mouth and be thought a fool than to open it and prove them right." ~unknown

        Comment


        • #5
          Set them all around 1 1/4 turns, and adjust from there. Be careful when bottoming the screws before turning them out, as the tips are fragile and can break. The 80-81 carbs pilot screw tips aren't quite as fragile as the older carbs though.

          Comment


          • #6
            Thanks John I will try that. I appreciate everyones help! I will let you know how it goes.
            Thanks again
            Greg
            XS1100 Midnight Special

            "It is better to close your mouth and be thought a fool than to open it and prove them right." ~unknown

            Comment


            • #7
              Damnit!! lol but seriously Damnit!!

              I believe I need some help...First let me tell you what I have done.
              1st I did the best I could to straighten out the front end after the accident and I believe it is straight(enough to ride anyway)I removed the entire front end, triple and all, then replaced them carefully as straight as possible. 2nd I completely stripped the carbs and soaked them in cleaner including all jets except the one with the screen on it in the bowl which I cleaned with carb cleaner. I put everything back together adjusting the main Idle spring as necessary to get the bike to start and Idle. I then went about adjusting the idle screws on each carb in an attempt to sync them up. The bike was Idling fine until....I put it in gear and took it for a test drive around the block and down the road, turning around and coming back...The bike began revving when the clutch was in all the way up to 5000 rpms. I had this problem before the accident but it was not as high only about 3000 to 4000 rpms. I can't figure out what is causing it! The bowls seem to be flooding a bit but not spewing gas out like before. At one time, close to when I first got the bike, the floats were sticking and causing a gas leak into the air filters onto the crankcase which I did my best to keep clean of gas as not to mix with the oil. I have been reading up on all of these separate subjects and I can't seem to figure it out. I just want it to run right. Do you think that the rubber seals around the screened jet in the bowl could cause this revving problem if they are possibly not sealing correctly? I am at a loss here...as I said I have been doing my research and I just don't know what to do! If you have any advice it would be much appreciated.
              XS1100 Midnight Special

              "It is better to close your mouth and be thought a fool than to open it and prove them right." ~unknown

              Comment


              • #8
                John. Is the float needle and seat located just rearward of the main jet? I have my 81 carbs on the kitchen table trying to learn what's what and how they work. The schematic in the manual seems pretty hard to follow on this. I think it is referring to this float needle as the valve seat assembly? And is this what can let fuel by if the petcocks aren't closing correctly? Thanks!
                80 SG
                81 SH in parts
                99 ST1100
                91 ST1100

                Comment


                • #9
                  Wow, lots o' probs here.

                  The bowls seem to be flooding a bit but not spewing gas out like before.
                  (You may have read this earlier in your research, but I'll post it again.)
                  From an earlier postSept. 23)
                  You'll need to pull the carbs again and check that fuel leak.
                  Take the floats and a pair o' pliers up stairs to the kitchen. Dunk them in a pot o' real hot water. The water heats up the air in the floats and it expands. If one of your floats has air bubbles coming out of it, "She's a no good."
                  Grab one of your wife's baking/cookie sheets and sneak it back to the garage while she's watching Oprah. You'll need it later.
                  Look at the tips of your float needles. If there's a "wear ring" on the tapered tip, "She's a no good" (but still might seal)
                  Take a handful of Q tips and using some chrome polish, polish the insides of the float needle valves. Spray carb cleaner through them out the fuel line, and then from the fuel line back out the valves. HHHmmm can't recall if your valve have those little screens on them, so you may want to pull the valves and clean the screens. Also, check the condition of the fuel line. Cracked? Brittle? Chunks of rubber falling off? "She's a no good" Replace.
                  Clean all passages with spray carb cleaner and blow out mit der compressed air, if available.
                  Set the float height.
                  Lock the garage door so the wife can't come in, and place the cookie pan on the work bench. Place the carbs in the pan, upside down, with the bowls off. Using extra fuel line, hook the carbs up to your fuel tank, which you've prepositioned on your bench, sitting up on a milk crate or two. Turn the petcocks to prime.
                  The weight of the floats should stop the flow of fuel. Anything leaking past? No? Good! ((You'll also be able to see if any fuel is leaking past the O ring around the seat)) Go back to the kitchen and get something to drink.
                  "Honey, what are you doing in the garage?"
                  "Umm.. nothing Dearest... err , I mean, I'm making a present for you. You can't see it yet."
                  Back to the garage. Still not leaking?
                  Turn off the petcocks. Put the float bowls back on and brace/support the carbs in the upright position. Turn the petcocks to prime. Watch for 5 minutes to see if fuel wells up from the main jet/needle area or out one of the air jets at the mouth of the carbs. Nothing? Go back upstairs, passing the wife, and ask her what's her favorite color. (She will now leave you alone till you've finished the gift for her)
                  Check your carbs again in a half an hour. If there's no fuel in the pan, and the carbs are dry, you're done.
                  Leaks....? Would be from those worn float needles mentioned earlier, or the float is sticking or improperly set.
                  Ignore wife... ("She's a no good") as she'll be ignoring you for a few days when she finds her baking sheet missing. Small price to pay for good carbs.
                  Install on bike and synchronize

                  High revving: With bike running, carefully spray WD40 or carb cleaner around the carb's intake manifold boots. If you have an air leak there, you'll hear the bike either rev up or stumble as it sucks in the fluid. If you didn't fully disassemble the carbs before soaking, the seals around the throttle plate shafts might be ruined and leaking air, also.
                  Throttle cable also could be sticking, misrouted or adjusted too tightly. Should have a little play at the handgrip, and if the engine revs when you turn the bars to the left or right, it's pullin' and too tight.
                  High Idle: someone mentioned earlier to make sure that the clamps holding the carbs to the manifolds is not interferring with the motion of the throttle cable mechanism.
                  Are you saying that: with the bike warm, in neutral and nicely idling at around 1100 rpm or so... just pulling in on the clutch causes it to rev to 4000?
                  Have you checked the plungers on the enrichener circuit?(Choke) Are they all stick hooked to the activator rod and move uniformly when you flip the lever? A plunger stuck in the open position would also cause extra fuel to be supplied.
                  "Damn it Jim, I'm a doctor, not a mechanic!' ('Bones' McCoy)

                  Comment


                  • #10
                    Re: Damnit!! lol but seriously Damnit!!

                    If the bowls are overfilling (yet not spewing gas like before), you definately have a problem there. I am not sure why you don't get the problems at lower engine speeds, because a leaking float valve (for whatever reason) would create a problem quicker near idle when the engine is consuming less fuel, right? I am wondering about the venting of the bowls. Early carbs vent through the upper hoses, later carbs vent through a hole in the inlet bell (which should not be blocked).


                    Originally posted by xsivelybad
                    (snip) Do you think that the rubber seals around the screened jet in the bowl could cause this revving problem if they are possibly not sealing correctly?
                    Skids (Sid Hansen)

                    Down to one 1978 E. Stock air box with K&N filter, 81H pipes and carbs, 8500 feet elevation.

                    Comment


                    • #11
                      Dean,
                      I think it is referring to this float needle as the valve seat assembly? And is this what can let fuel by if the petcocks aren't closing correctly? Thanks!
                      float needle = valve seat assembly. Those squinty-eyed jap engineers always have to make things hard. I mean... call it what it is. Float + needle = float needle, not "valve seat assemble"
                      Anyway.... yes, the float needle is what regulates the level of fuel in the bowl. It also "should" shut off the fuel if the petcocks don't turn off, but that's not their primary function. That's why bikes without vacuum petcocks have an "OFF" position on the petcocks, so fuel can be shut off, lest the constant gravity pressure overcomes the needle and seat area and allows fuel to seep into the carbs overnight, etc.
                      Had a bike last week with fuel in the oil. Needle and seat were relatively good, but the vacuum petcock wasn't turning off. Over night, or over the course of a few days, the constant pressure from the "open petcocks" would allow fuel to flood the carbs, etc.
                      "Damn it Jim, I'm a doctor, not a mechanic!' ('Bones' McCoy)

                      Comment


                      • #12
                        Improper term

                        Ok, It was wrong and racially insensitive for me to say... "Squinty-eyed Jap Engineers."
                        My apologies to squinty-eyed engineers everywhere.
                        "Damn it Jim, I'm a doctor, not a mechanic!' ('Bones' McCoy)

                        Comment


                        • #13
                          if the floats are leaking/off set and allowing fuel to over flow, this can cause a high idle. After fixing my float height/ float valve, my high idle was gane and I had to use the throttle stop screw to keepit at idle. The extra air here at sea level, after moving, must have been enough to put the extra/leaking fuel to use and increase my idle speed. Something to keep in mind if you had leaking carbs before.
                          '81 XS1100 SH

                          Melted to the ground during The Valley Fire

                          Sep. 12th 2015

                          RIP

                          Comment


                          • #14
                            Just found the float needle. So what is that very small jet(?) just to the rear of the main?
                            80 SG
                            81 SH in parts
                            99 ST1100
                            91 ST1100

                            Comment


                            • #15
                              That would be the pilot jet, I believe.

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