Originally Posted by
kanawa
0.1875"....it's not the bearings.
I assume that's the bearing size (3/16"). What does the stack height gap measure? It looks like 2mm or so.
Velobase tells me the SR stack height of 42.2mm is taller by a good margin than just about any headset any of us would install on a bike with vintage Campy. NR is 42.0. The Gran Sport is way shorter (34?). The current VO offering is shorter. All the current Tange options (the "go-to" for most of us) are shorter (e.g., the Tange Levin CDS is shorter by 12mm).
If you grind 2mm off the steerer, the world will not end.* But neither will it end if you add a 2mm aluminum spacer.
* You may go to hell (as one poster wanted), but not for that.