After rebuilding and re-syncing the carbs, replacing the plug wires and coils, cleaning the tank, adjusting the valves, rechecking the timing, cleaning and inspecting all of the Dyna ignition connections, doing the tests recommended by the Dyna Tech, I decided to remove the Dyna Electronic ignition and re-install the stock points type ignition.  My R75/7 now starts and runs like a champ!  

Good job!  My 78 had a Dyna ignition for about 12 years. It worked great until the day it didn’t. Like a lot of such items, it quit when hot. Then it would run again when cooled. Yours exhibited some very strange behavior!

If you do stay with your points ignition, I can HIGHLY recommend the Dynatek DBR1 “Booster”.  It is a simple, bulletproof addition. I don’t think it boosts a thing, but it does reduce the voltage and current load at your existing ignition points to nil.  The result is that the points last a really, really long time. It connects under the tank only.

Enjoy your R75!  That is a nice machine. 

You need to be aware that the stock ignition has an advance curve that was designed for 1980 fuels. Those were leaded fuels with an octane of 100+. Today's fuel is not even similar, and because of that you may experience "spark knock" or other ignition irregularities.

I understand why you did the conversion that you did. But you need to understand that the change in fuels, and the problems that change causes, is the primary reason why Airhead riders convert their ignitions over to a recent model "electronic ignition". In those units the advance curve is controlled by software and is a lot different. So simply be alert to any performance issues in this area.

Hope this helps.