the starter solenoid is separate to the ignition coil
I'd go back to basics a little and 1st check the condition of the engine earth connections, also if its on the weber carb I'd also check the level or fuel inside the float bowl as it should be about 2/3rds full - if its lower than this, try checking that the float valve isn't sticking and you can also adjust the tab on the back of the float so it sits higher
also check the wiring to the ignition coil for heat damage as it can expand with temperature
its not integral but switched by it?
so as you release the key the coil voltage is then dropped to 6V
I'd also consider switching to a slightly more modern 12V coil that needs no switching between high and low voltages and so can just be wired to the 12V ignition feed
do you still need help?
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