Yes, you can test with them on the scoot.
I highly doubt the regulator will start dropping voltage, it works, or doesn't, in my opinion.
If it is the regulator and revving does not increase voltage at the battery, Google for instructions on testing it.
The stator usually has three wires coming out of it, and each must have the same certain electrical value, but I am not electrical so can't advise further other than again to Google for instructions.
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