Strange one for you, Bike runs fine ... turn on headlights it starts to hiccup and spit now and then and sometimes just stalls, Changed battery, no avail, It's got a new rectifier on it, seems to be under-load it starts to

. What do you guys reckon it could be? I DO have car bulbs in there at the moment (Modified a H4 to fit) Think its worth me swapping out that for a motorbike one?
Any suggestions? cheers.