Powerdynamo, testing ignition - how ??

Powerdynamo brings new ignition & light
to your vintage motorcycle



Technical Help



Customers quite often start report on encountered problems with "I have tested ignition and there was no spark"

We always will have to ask back "How did you test? ". This might sound a bit arrogant to ask back like this, but a lot of instances where customers think there is a problem are instances of wrong testing and not malfunctioning.

Here the most frequent errors during testing procedures:

  • checking  spark by turning the rear wheel with a gear engaged will in most cases NOT result in spark. You simply do not get the needed crankshaft speed for a magneto ignition.  This will have worked with the points based ignition, but not with magneto based ignitions. Here you need about 300 revs for starting. With our high-speed racing systems (inner flywheel) you even need 500 revs,
  • taking the spark plug(s) out and pushing the kickstarter by hand will neither have a good result. Again, speed is too low. 
  • using electric drills to make the flywheel spin in our experience is not always good either.

    >> you need to kickstart by foot as normal (for some racing applications you will even have to push start)
  • putting the the loose spark plug against the engine casing to see spark is a further  source for mistake. This can definitely not be done when you are alone. you can not kick, press the plug for good contact against the engine metal  and look at the same time. Already much better when a second person kicks, but you very likely still have the problem of bad contact (your engine body might be corroded, dirty, not good for ground contact)

    The whole thing definitely becomes unworkable with 2 spark plugs. You will never manage to keep both of them in good contact with  ground. (see also special remarks on twin ignition coils)
  • there is always the problem of seeing the very focused spark of CDI systems. See here
    Note: we have customers who report they have tested high tension with their fingers as they did not see spark. Please do not do that!. We can have up to 40000 dangerous Volts there!

    >> the most indicative method of checking spark is with a stroboscope clamped to the high tension cable (clamp) and the spark plug(s) firmly positioned in the cylinder head. The stroboscopic flash will clearly indicate you whether there is spark.
    NOTE: some strobes are phase sensitive. That means you might not get a flash unless you  reverse the induction clamp by  180 degrees (with our twin coils, one exit is one way, the other the opposite way). More info see here.

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