If it is a K4, you don't have a headlight cutout with the starter button and the problem is elsewhere. Since the high beam works, the problem is elsewhere anyhow. Look for a brown heat discoloration around a blue/black wire in the large connector in the left side of the fairing or behind the radiator top shroud. If you have continuity on both sides of connector with that wire, the likely culprit changes to the hi/lo switch.