adjusting LH Bing

Discussion in 'Airheads' started by bernardofeio, Feb 11, 2013.

  1. bernardofeio

    bernardofeio Bernardo Feio

    Joined:
    Feb 28, 2011
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    Portugal
    Hello<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" /><o:p></o:p>
    <o:p> </o:p>
    My R100GS is running a bit unregular and I decided to clean the Bings. After everything back on place I adjusted them as the manual says. <o:p></o:p>
    <o:p> </o:p>
    After adjusting the LH Bing I passed to the RH one. With the engine running on idle when I screwed the mixture regulator I was expecting some engine reaction but nothing happened…. <o:p></o:p>
    <o:p> </o:p>
    I screw it till the end and I even complete remove it and the revs didn’t change… any idea what is happening? (the hole is not clogged)<o:p></o:p>
    <o:p> </o:p>
    Thanks in advace<o:p></o:p>
    Bernardo Feio<o:p></o:p>
    #1
  2. Airhead Wrangler

    Airhead Wrangler Adios Mexico

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    The idle jet itself may not be clogged, but some part of your idle circuit DEFINITELY IS clogged, otherwise adjusting your mixture screw would have an effect. I'd suggest a more thorough cleaning and be sure to blast out EVERY little passageway with carb cleaner and compressed air. Be sure to get the openings in the carb throat; the air intake and exit for the idle circuit. Also remove your mixture screw and blast carb cleaner/compressed air up into the idle passage that way as well.
    #2
  3. JonnyCash

    JonnyCash turd polisher

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    Be sure that the choke lever on the carb is going to the fully off position. If the cables for it are out of adjustment, or worn, sometimes the choke wont come all the way off. My friend had this going on on his 90/6, and it drove him nuts trying to figure it out. He brought it over, and it took awhile to figure out what was going on, there were numerous red herrings, but in the end, I loosened the pinch bolt on the choke lever on the carb, and found that though it looked like it was bottoming out, it wasn't. That fixed it.
    #3
  4. georgesgiralt

    georgesgiralt Been here awhile

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    Hello !
    The last possibility could be that the throttle disc has been mounted either badly centered or in reverse, preventing it to fully close and seal the passage. (it could also be that the O rings at the throttle axle had been destroyed during cleanup)
    #4
  5. supershaft

    supershaft because I can

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    The last possibility? I thought that was funny. I have never tried taking the mixture screw completely out but I have seen mixture screws be completely ineffective and the carbs where in perfect shape numerous times over. The mixture screws were ineffective for the valves leaking. I have seen a bad spark plug cap act just like a idle circuit issue a couple of times. For some reason they only effected idle.
    #5
  6. pigeyes

    pigeyes bilge rat

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    eh, mate have you met that bloke Planktonn, reckon you and he should open a shop together,should go well together .
    Just an idea!
    cheers
    mick.
    #6
  7. supershaft

    supershaft because I can

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    I should read his thread more often. I find a lot of his posts interesting. Off hand, I am not familiar enough with him to know but you might be right. I have seen no red flags so far. :D
    #7
  8. boxerboy81

    boxerboy81 Stay Horizontal

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    Bernardo, remove the mixture screw. Inspect the o-ring whilst you're there.
    You need to ensure the passageway above the mixture screw is clear. It opens to the carb where the right black dot is. I run some fishing line thru it, then carb spray, then compressed air. Do that from the top down so that junk can drain down and out.


    [​IMG]
    Whilst you're there have a look behind the right black dot, just behind the butterfly, there is another hole that goes to the pilot jet. After removing the pilot jet, flush and air blast that too.
    #8