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    Pffft chik

    Pfft chik is as close as I can get to describing an intermittent sound I am getting from the Bandit 1200.

    It occurs more just after start up than after warmed-up, but it can occur any time at low speed and is mostly noticed while coming to, or at, a stop.

    It is not a continuing sound, but truly intermittent....it occurs one at a time only, although sometimes it might happen twice in one minute, or it may not occur even once in 15 minutes.

    Problem? I hear it when I am on the bike but, just like going to a dentist or mechanic, it does not do it when I put the bike on the stand and get down to listen for it, even when I wait for five minutes.

    The bike starts well, idles normally, has no problem with pulling away either slowly or hard, is happiest at 4500 to 5500 and will double that with ease if opened up.

    It is somehow connected with firing, as, when the engine is cool it sometimes causes a momentary hestitation, barely noticeable, but there.
    The hesitatin is also intermittent. Usually there is none.

    When warm the hesitation is rarely noticed, so rare I may be imagining it, but the sound is there.

    I am not sure if I hear it at higher RPMs or not.....I sometimes think I do but this is only while driving and so I cannot be sure either way.

    I have considered:

    Loose spark plug...that would explain the pffft part of the sound, but not the chik that usually follows a split second later (it does not always follow)
    but that would come from internal pressure and keep on happening with every firing.



    Valve seals/Backfire into carbs, but it does not fit with the rarity of occurrence.


    Valves not closing and igniting on wrong stroke...that could explain the hesitation, but it should be much more frequent and more harsh.





    Timing off....same thing, it is TOO intermittent and the engine runs well at all RPMs.



    Crossfiring from the coils/plug wires ....that could cause the chik part of the sound and a hesitation.

    I am still wondering about this. I even sat in the garage with the lights out to wait for visible sparks....but nothing happened.


    Ideas, please?
    Bertrand Russell: 'Men are born ignorant, not stupid. They are made stupid by education.'


    #2
    Perhaps one of the coils (or coil lead) is arcing under the tank, might explain why you can't see it in your dark garage.

    Stuff like that will drive you crazy, ehh??
    '85 GS550L - SOLD
    '85 GS550E - SOLD
    '82 GS650GL - SOLD
    '81 GS750L - SOLD
    '82 GS850GL - trusty steed
    '80 GS1100L - son's project bike
    '82 GS1100G - SOLD
    '81 GS1100E - Big Red (daily rider)

    Comment


      #3
      Does anyone have any ideas yet?
      Bertrand Russell: 'Men are born ignorant, not stupid. They are made stupid by education.'

      Comment


        #4
        Dunno. I get a similar pfffft ting every time I shut off the Harley engine, and every time I shut off the GN125 engine. Both otherwise run fine.

        I'm leaning towards the view that maybe they are both running a touch rich, and it's just a little left-over fuel blowing off in the exhaust, but damned if I know

        Comment


          #5
          Maybe the "Pfft" is a backfire through the carbs, and the "chik" is the next power stroke not firing because the fuel was already burnt in the backfire?
          http://img.photobucket.com/albums/v5...tatesMap-1.jpg

          Life is too short to ride an L.

          Comment


            #6
            Originally posted by tkent02 View Post
            Maybe the "Pfft" is a backfire through the carbs, and the "chik" is the next power stroke not firing because the fuel was already burnt in the backfire?
            Could be, but it seems to be in the exhaust - baffled

            Comment


              #7
              Get a few more similar bikes together and you can start your own break-dance crew.

              Pffft chik, Pffft chik - wokka, wokka, wokka!!

              Comment


                #8
                Originally posted by Zooks View Post
                Get a few more similar bikes together and you can start your own break-dance crew.

                Pffft chik, Pffft chik - wokka, wokka, wokka!!

                Zooks, I think you are overdue for a wokka bout.
                Bertrand Russell: 'Men are born ignorant, not stupid. They are made stupid by education.'

                Comment


                  #9
                  Originally posted by argonsagas View Post
                  Zooks, I think you are overdue for a wokka bout.
                  Or some good Pfft chik
                  http://img.photobucket.com/albums/v5...tatesMap-1.jpg

                  Life is too short to ride an L.

                  Comment


                    #10
                    When is the last time you changed the air cleaner element?

                    Earl
                    Komorebi-The light filtering through the trees.

                    I would rather sit on a pumpkin and have it all to myself than be crowded on a velvet cushion. H.D.T.

                    Comment


                      #11
                      sounds like the headlight to me.

                      or maybe the loose nut between the seat and handle bars

                      there has to be a term for motorcycle hypocondriacs
                      SUZUKI , There is no substitute

                      Comment


                        #12
                        Originally posted by earlfor View Post
                        When is the last time you changed the air cleaner element?

                        Earl
                        A valid question.


                        I have not changed it.

                        The bike got a full summer treatment in the bike shop at the beginning of May, 2008.....synthetic oil, all filters, new rear tire.

                        Everything was set up well. That was Saturday. Tuesday morning the bike was taken to another shop after being hit by a car. I did not get it back for almost two months.....not that it mattered because I could not ride it due to back injuries from being hit.

                        I got only a few hundred miles in riding last year.

                        This year about 2000 miles.

                        So roughly 2500 miles since last year.
                        Bertrand Russell: 'Men are born ignorant, not stupid. They are made stupid by education.'

                        Comment


                          #13
                          Originally posted by trippivot View Post


                          there has to be a term for motorcycle hypocondriacs
                          There is now. Pffft chikers.
                          http://img.photobucket.com/albums/v5...tatesMap-1.jpg

                          Life is too short to ride an L.

                          Comment


                            #14
                            Originally posted by argonsagas View Post
                            A valid question.


                            I have not changed it.

                            The bike got a full summer treatment in the bike shop at the beginning of May, 2008.....synthetic oil, all filters, new rear tire.

                            Everything was set up well. That was Saturday. Tuesday morning the bike was taken to another shop after being hit by a car. I did not get it back for almost two months.....not that it mattered because I could not ride it due to back injuries from being hit.

                            I got only a few hundred miles in riding last year.

                            This year about 2000 miles.

                            So roughly 2500 miles since last year.

                            The reason I asked is my Bandit every now and then (maybe once every couple of days), would cough and skip once. I could find nothing wrong with it. Finally, I looked at the air filter and the element was darkly discolored, not clogged, but did have some dirt accumulation. I put a new filter in and it has not skipped since.

                            Earl
                            Komorebi-The light filtering through the trees.

                            I would rather sit on a pumpkin and have it all to myself than be crowded on a velvet cushion. H.D.T.

                            Comment


                              #15
                              Originally posted by earlfor View Post
                              The reason I asked is my Bandit every now and then (maybe once every couple of days), would cough and skip once. I could find nothing wrong with it. Finally, I looked at the air filter and the element was darkly discolored, not clogged, but did have some dirt accumulation. I put a new filter in and it has not skipped since.

                              Earl
                              Thank you, Earl. I may not get to do so until the weekend, due to workload, but I will check it.
                              Bertrand Russell: 'Men are born ignorant, not stupid. They are made stupid by education.'

                              Comment

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