If  you put a voltage meter on the stator lighting circuit, it it will usually make about 50 volts AC at high RPM without a load on the system.  If you check the voltage out of the voltage regulator without a load on the system, it will usually be about 13 to 15 AC volts.  It will not charge a battery unless you put a rectifier to convert the voltage to DC

If you check the peak voltage out of the ignition source coil on the stator it should be be at least 100 volts peak and over 150 peak at higher RPMs.