89 XR4 150hp - ignition question

Does anyone know how many times each spark plug fires per revolution?

Basically I'm bringing my old XR4 back to life and it has a bad voltage regulator which I have disconnected. So before buying a new voltage regulator and stator to convert away from the problematic water cooled regulator I want to run the boat and stress test the motor. But with the voltage regulator being smoked I have no tach, so I bought a simple inductive tachometer where you wrap a wire around one of the spark plug wires and I need to set it based on number of sparks per revolution for that single spark plug so it can calculate the RPMs right.

I hooked up the inductive tach tonight and the "3 sparks per revolution" setting looked to be the most accurate but I wanted to double check and see if that's correct for this motor.

Ones every revolution. You can connect your grey tach wire to one of the yellow wires of the stator at a yellow wires connection.

1

Wonder if this inductive tach is picking up noise then, the 1 per revolution setting said it was idling at 2400 rpm and there's no way it was that high.

Hooking the grey wire to one of the stator's yellow wires won't send too much current to the tach and smoke it?

Tried hooking up three different tachs to each of the yellow stator wires but got no readings on the tach, just stayed at 0.

Tried hooking up three different tachs to each of the yellow stator wires but got no readings on the tach, just stayed at 0.

yes that is possible on muffs

Mine idles at about 1800 on muffs much diff on lake