Originally Posted by
plonz
-Front brake clearance with headset bottom cup. Just encountered this with a new 105 5800 brake caliper. It's bulky on top and hits the cup. Required some spacers from abovementioned parts bin.
+1, I had the same issue with the 5800 front brake. Filed it down just a bit in the offending area and used a couple extra washers to help it clear the headset.
Good advice, only thing I have to add is to check out the retro roadies thread if you haven't already. So many examples of great bikes based on vintage frames with modern components.