basket case paso
installed wiring harness but have no spark when turning over.
plugs spark when ignition key is turned on both at same time.
just once every time key is turned on.
wiring not right ?, failed components?
every thing else seems to work.

sounds to me like you have power to the coils but not to the ECU ,or a fault in the sensor circut . I think that the 750's had a koukusan ignition which was essentially one seperate unit for each pot , and it is unlikely that both units have packed it in at the same time , much more likely to be something both units have in common , like the power supply or the earth

Check the RPM sensor on the flywheel.
I had it broken and the bike used to stop with no spark.
Ciao