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You report: I get only spark on 1 cylinder with my Powerdynamo system using a twin coil.
We get again and again reports from customers that they get only spark on one cylinder with Powerdynamo systems using a twin coil.

Without wanting to deny that a twin coil may be faulty in the way of only one exit firing, we always really hesitate to accept those reports and indeed in by now over 10 years and with something like 8000 such coils used we never had such an instance.

Those coils always fire on both exits (or none at all).

Why are we always so sure about this?
Have a look at the basic wiring for those coils:
In coils with one exit:
  • one end of the secondary coil is connected to the spark plug and the  other to ground.
  In our twin outlet coils:
  • both ends of the secondary go to spark plugs.
    That means that effectively there is only one coil and this is either working or not. It can not fire only on one exit!
So what happens? Customers are surely not making this up, they experience something.
The e.g. use a strobe and it only flashes on one HT lead.
 
# Report: I did put a strobe light on each HT lead (at the same time) and it was missing on the RH side.
  • We than did ask to please turn the capture clamp on the ht wire not making the strobe flash by 180 degrees - and all of the sudden the strobe did flash.
    Why: The 2 exits are phase shifted by 180 degrees and many strobes recognise only one way.
The best way to get convinced that it is not the coil, but the spark plug/cap and/or cylinder/carb arrangement is  to:
... change (swap) the leads/caps at the cylinder, not at the coil. We bet you will now still see the same cylinder malfunction - despite the swap of the HT feed.
Why: (This tuned out mostly only after more examination) the cylinder in question did not have compression or the carb setting was wrong.

than also swap the spark plugs and the caps. problem should be exported to the other cylinder because of faulty plug

The really only possible coil fault (which so far has not manifested yet) leading to only one exit to fire is that internally there is a shortcircuit to ground, no other option.
For more things to know about those twin coils an percularities of same please see our information here.

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