testing.....
The regulator/rectifier is part of the charging system. Your magneto puts our an un-regulated AC power supply. The rectifier converts this to DC and the regulator maintains the output voltage at 14 to 14.5 volts DC.
To check it, get a good charge on the battery and start the motor. With the engine running, take a multi meter and put the probes on the battery. You should get a reading of 14 or just above.............:cheers: