Can anyone tell me when Campagnolo were manufacturing chainwheels this size? I have a mid to late 1980s chainwheel which when I measure c-c on the adjacent bolts gives me about 68mm which I believe is a BCD of 116 - now obsolete according to Sheldon Brown's website. I wonder if I may be measuring this wrong, though I can't see how. I'm selling this on ebay (item #3687164981) and a potential buyer just asked me for the BCD.
Joss Winn, Berkhamsted, UK.