I dunno but they all do it and go milky. I've had it with 748 and with Supersport, and to get them clean I usually strip the lamp down and get a bit of diluted clear vinegar in there. In the 748 it's fiddly and I've used cotton buds, toothbrushes and baby bottle brushes to get all of the milkiness off the inside. I don't know whether it's something to do with the light itself, or temperatures or condensation but it does let the bike down a little at the moment. Still, in these last few nice weeks of the year it's important to enjoy the riding. The preening can wait...
