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No ignition sparks at the plugs

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Gary400/4:
Hello all, I have been toiling away over a couple of years in my shed resurrecting a forlorn cb400/4. The problem I now have is trying to get it to run. Engine is rebuilt, good compression engine turns over on the starter motor. I have 11.7 V measured at my ignition points terminal. This means current has flowed through my primary windings in my coils then out on to my yellow and blue wires. I can manually open the points to obtain a spark across them. The points are timed to start to open at the F1-4 and F2-3 marks. I have fitted new capacitors. Points gap set at 14thou of an inch.
The coils are Tec FL703 type, the primary resistance measured at approx 5.5ohms the secondary windings measure at approx 12Kohm. Without suppressor plug caps.
I have also noted that when the points open, if a analogue meter is used the pointer will drop towards zero. If I use a digital meter. The low resistance across a closed set of points should go quite high in terms of open circuit resistance, when the points open. But I am detecting 7 ohms of continuing continuity. Suggesting a resistive open circuit short circuit to ground. This has me thinking this is offering my ignition voltage  a low resistance path to ground, lower than having to energise a collapsing electrical field inducing an emf into the coil secondary windings. It's all well and good putting new coils on, I am not 100% convinced that will solve my lack of spark problem.
On the points, I do wonder if the tiny insulting ring that passes through the the terminal screw tab, and has insulated discs either side, can loose some resistance.

taysidedragon:
It's difficult to diagnose the problem without seeing it up close.

I would check that the points wiring and insulators are connected in the right sequence. Then check continuity on the wiring all the way from points to the coils and double check that the coil connections are the right way round!
It's unlikely that both coils are faulty, but they might be. If you can get hold of a known good coil, try that in place of one of the existing coils. Hope that helps.

SteveD CB500K0:
Did you say that you get a spark at the plug when you manually open the points?


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mike the bike:
You can simulate points by shorting the blue (or yellow) to ground and then disconnecting.   When you disconnect, you should have a spark.
This test should prove the coils to be good or bad.

Bryanj:
Sounds like maybe corrosion or preservative on contact surface.
If not and spark occurs when you manualy open the points with everything connected the cam is either/or/both not opening points enough or at correct time

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