How do you know if your voltage regulator is bad or if it is the stator?

To determine if the issue lies with the voltage regulator or the stator, first check the voltage output from the stator using a multimeter. If the stator is producing the correct AC voltage but the battery isn't charging, the voltage regulator may be faulty. Conversely, if the stator is not generating the required voltage, it is likely the stator that is bad. Additionally, visual inspection for signs of damage or overheating can provide clues about which component may be failing.