Originally Posted by HillRider

Right idea but the wrong details. Campy does not, and AFAIK has never has made 130 mm bcd chainrings.

What you are thinking of is Campy's compact cranks with a nominal 110 mm bcd. Campy made the bolt circle 110 mm like everyone else BUT offset one bolt a bit so their rings wouldn't fit on any other 110 mm crank and no other 110 mm chainrings would fit on a Campy compact crank. Cute huh?

Again, IIRC, they only did this for the Record and Chorus compact cranks. Centaur, etc. did use a standard 110 mm bcd and would accept other makers rings.