It's a Silverstar that I put in there not long after I got the bike. Hope that's not it, but I'll whip out my multipeter and see if I can divine any useful info out of it.Gumpy said:The bulb is dual fillament. Could be the high fillament is open. If you have a multimeter, check resistance of both fillaments. Also can check voltage for both high/low at the bulb socket. If no voltage for high, then look into the switch.
I'd bet it's the bulb.
Gumpy