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?
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?
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