I've been noticing my headlight would dim at a stop light but when I rev the engine a little it gets brighter. It also does it when I have my heated gear on. The Gerbings thermostat will blink since I have it turned down and my headlight will dim every time the thermostat blinks.
I'm about to install my DDM HID kit and not sure how it will deal with this.
I'm thinking my battery is the cause but I could be wrong.