Ignition failure

I've posted this on BritBike, also:

I've installed a brand new TriSpark unit and new coil (12V) in my '74 - a bike that I have had running on Trispark and 12 V coil for at least 6 years. A short circuit (break switch leads) appeared to kill off my ignition unit, so I tried an old Boyer and (also Boyer) 12Vcoil - that worked, but the (Boyer black box) unit was faulty and would not allow any advance. I thus dumped the Boyer and purchased the new Trispark.

I statically timed it and it started for a few seconds, with ease. Put the tank back on to dynamically time it - but could get not a single spark. I removed the tank, checked all wires - no spark. Jumper wire from negative terminal (positive earth; 12.6V across battery terminals) to black/yellow short wires in Trisapark unit, and another jump wire from the short black/white wire to one of the coil terminals. The other coil terminal is grounded (doubly checked). New, out of box, spark plugs. Suppressor caps as supplied in the kit (5k ohms). As I turn the engine over, the LED on the TS board flashes, but there is NO spark from the plugs. I thus removed the TS and changed to Lucas 6V coils and (Lucas) plug wires in series - still no spark. Checked spark
I tested the TS unit as per instructions - no spark at all, let alone ever increasing sparks.
Measured the resistance of coil HT wires from cap to end which inserts into 12V coil - seems to be infinite! Changed wires and caps - now measures 4.9 k ohms - but still no spark.
Measured resistance of old, Lucas wires and caps - appears to virtually zero, but used them with the Lucas coils.
I'm flummoxed! I must be doing something wrong, but can't figure it out.
Any and all advice greatly accepted.
Thanks in advance,
Paul.

Boyer showing fixed timing can be sender wires reversed.

Other than that, I think you should talk to Trispark.

Thanks, TT, switched them around without any change. Spoke with Boyer - their conclusion is bad black box.

All of these E-units require a good ground point. Clean it up then try again ? :?

http://www.nortonownersclub.org/noc-cha ... /543612281 you have probably looked at this... i would always put a fuse in the ignition circuit... this is pazon advice - to protect the unit. i would check to make sure your main switch is ok and not knowing what kind of fuse holder you have -do ensure that if you are using the old glass type fuse that you have one of the right length ... this has caught me out quite recently...
and try disconnecting the large capacitor... and see if it runs with the zenner disconnected-

Thanks, Torontonian - added an extra ground, to be certain.
OldMikew, the Zener and large capacitor are long gone. Also doesn't explain why this still happens when I run a jumper wire from neg pole directly to Trispark and from Trispark directly to coil.
I've learned my lesson about fuses!
Thanks

Re reading your post... is the 12volt coil from your original tri spark ? Is the new ignition unit the same or does it want to see a different 12volt coil with different impedance .. that is resistance loading . Tri star would be able to tell you that

the fact you have hotwired the coil and tristar doesnt necessarily mean you have bypassed a fault but might now be wired in parallel to it... do you still have the warning light simulator? if so try disconnecting all leads to it

Paul
hope all is sorted... do let us know what it was