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Coughing through carb when key turned to light position

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  #11  
Old 06-25-2019, 02:06 PM
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has the been from the start?
using two coils?
coils close together?
plug wires parallel and close to one another?
here is what "MAYBE" happening
key on, power goes to the coils. coils fire when ground is lost if the module is allowing it even though it is not sending out trigger signals.
the coils are inductors, inductors try to keep current going. the coils saturate and then the current drops since module is not switching, this momentary current is induced back into the coil just like when the module chops current, if coils are close by, this feedback could build to the point of actually firing the plug.
what to do, add separation, run wires 90* apart, shield them, add separation to the coils you could add some capacitors to shunt the falling current or absorb enough energy so the plugs cannot fire. add some shielding to the plug wire and make sure one side is grounded.
 
  #12  
Old 06-25-2019, 05:37 PM
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^^^ Bullshit ^^^
The COILS SHOULD NOT FIRE UNLESS THE ENGINE CRANKS.
His ARE FIRING AS SOON AS HE TURNS THE KEY, BEFORE HE HITS THE START BUTTON.
 

Last edited by RANGER73; 06-25-2019 at 05:39 PM.
  #13  
Old 06-25-2019, 06:39 PM
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tell you haven't been by hd for long
had a friend of mine that could start his by putting the engine in position and just cycling the key.
if you READ, inductors keep current flowing and when you turn on power, power WILL flow to the coils, aka builds saturation and then stops since there is no trigger. the magnetic field drops and by induction could possibly fire the plug BUT things MUST be right for this to happen.
some people like to loom their wire, bad mojo and emf can be introduced where you do not want it to be.
 
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  #14  
Old 06-25-2019, 07:52 PM
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He doesn't have a stock ignition, It's a Dynatek ignition. The new single fire coil is hot all the time when you turn on the key and gets a ground signal from the Dynatek module to trigger spark.
 
  #15  
Old 06-25-2019, 08:19 PM
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Ok, so I played around with it.

I have the dynatek twin fire coil, so it's basically two single fire coils in one package ( I think). There is a hot 12 V wire that powers both coils, and then to each side of the coil there are a blue wire (front cylinder coil / spark plug) and pink wire ( rear cylinder). These come directly from the dynatek ignition in the cone. As I turn the key and power it up, only the blue wire (front cylinder coil sparks). I tired moving the blue wire to the other coil , where the pink wire was hooked up, and it sparks there too. If I remove the blue wire completely, the coil is still powered at 12V but no sparks when i turn the key so that stupid blue wire that comes directly from the dyna 2000 module is doing something when the dyna2000 module first gets current. It only happens the second I turn the key and doesn't happen again until i crank the motor - if I disconnect the blue wire from the coil, turn the key, then connect the blue wire back to the coil, it doesnt spark and there is no issue. One easy and pretty ghetto fix would be to put a switch on the blue wire and have it be in the off position when i first power the bike. Then I can easily turn that switch on and we're in business, I think that should fix the issue. HOWEVER, I would like to figure out what the true cause of this is and fix it from there, if possible and doenst entail taking the whole bike apart again to find the cause. My suspicion was that maybe the blue wire is grounding somewhere along the way, but if that was the case, i dont think the ignition would work properly when the bike is running - which it does. Starts right up and runs smooths and properly, or at least so it seems..

Oh yea, I also zapped myself a few times in the process.

Thoughts?
 
  #16  
Old 06-26-2019, 10:59 AM
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Like I said Days ago, the Dynatek is FUBAR,
Non repairable, maybe warranty?
 
  #17  
Old 08-03-2024, 01:12 PM
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Default same problem

did you find what was the problem
 
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