No spark

In that case either the large battery stud on the relay is losing power..........

(Clip your meter onto the large relay stud and to ground. Twist the key to start. Either way the stud should show "same as battery"

OR........... the wire from the relay to the solenoid is open. That would be fairly rare It happened to me on my 69RR It still had the original battery cable where the two wires are molded together at the starter. The wire had broken up inside the molding

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