Instructions
Contact the Campagnolo company. The company keeps records of its different products, including cranks. Send in a photo of the crank you would like to have identified. You also can request catalog information for the part in question.
Search on the Campy Only website for information and photos. This website maintains a large gallery of Campagnolo enthusiasts displaying their bicycles with Campagnolo parts. The website also includes company catalogs for Campagnolo parts dating back to the 1950s, which you can use to identify and research different cranks.
Post photos of the crank and requests for information on the Retro Bike Forum. This forum is frequented by bike enthusiasts, mechanics and experts who are eager to help.