AC systems Blowing headlight globes.
Early AC-DC systems had no regulator to control the Lights voltage, they were balanced system and worked OK as long as they were fitted with the correct voltage and wattage globes, in most cases this worked OK. A problem arrose when the Laminations that the windings were on "Shorted-Out", then uncontrolable voltage caused globe blowing. The only remedy is to place an AC Regulator in the system.
Most modern AC-DC systems are fitted standard with an AC regulator, they are usually in conjunction with a DC regulator for battery charging. eg. WR Yamaha, KTMs etc.
We have both 6 and 12 Volt AC regulators, see Instructions below.