The top tube is 56cm center to center and the Head tube is 138mm tall. The Serial Number is 9100XX so from 1991. The Bike is a Beauty, immaculate, and a show stopper. The bike has NOS Campagnolo Century Finish Corsa Record Parts: Cranks, Front and Rear Dérailleurs, Sheriff Star Hubs, Headset, Delta Brakes, and Brake Levers, Real Nice Stuff.