A friends son has a R4 scooter and the head lamp has gone out on it like two times. I have checked the circut and it all apears to be working properly. I need to know if any one has had this issue and if so what did you do to fix it or work around it? Is there a off the shelf replacement for the bulb and if so where would one go to get it? Please note it is the two bulb head light system.