Originally Posted by DRONE
Not to put down PIAA--they make great products for motorcycles and their heavy duty bulbs are very tough. My HID light kit from Martin Fabrication uses PIAA bulbs. But . . . their H4 bulb has the same yellow color as the BMW bulb--about 4000k. It does not improve conspicuity. But I had a chance to swap bikes with a buddy last month and see my 6000k H4 Halogen Bulb from Luminics USA
in the rear view mirror and it's really brilliant silver white--very conspicuous in daylight. Like a shiny diamond. The one I got they call the "Pure Blue" bulb, not the "Krypton Blue". They only cost $35 for two bulbs.
AAhhhh.. think I follow now. The HID lights are only the doodads sticking out the sides then, which light up the area of the road closer to the bike. And the H4 is just an alternate bulb. Cool. I wrote Martin Fab but I think they misunderstood my question because I was confused myself. :)
I think I'll start off with the pure blue then and see where that gets me. An HID set can wait for now. Thanks again for the info. I think you have all saved me months of research!