I've recently finished replacing the OEM headlight on my 1100s with an old style round one.
Like one or two other members I purchased the bracket and headlight from Motodemic in the states (bloody expensive) the bracket is a top quality bit of kit but the shell didn't look quite right and after fitting it I wasn't happy.
I then obtained complete round shell, purchased a Cibie sealed beam unit and one of our very own Mr Gazza's rings, I assembled the new configuration and I'm more than chuffed with the result.
Thanks to Gazza for producing the rings and so far those who have seen the mod have commented that it looks factory...
