This is the bike that Eddy Merckx set the hour record on in 1972. It was specially constructed for him by Colnago using a custom track frame and special components and accessories designed to provide the maximum in light weight. It weighed only 12.68 pounds or 5.75 kilograms. Many of the elements , such as the handlebar, bottom bracket shell, and crankarms were milled to make them even lighter. The headset was made by Campagnolo with titanium caps and weighed only 122 grams. The pedals and hubs were made of Soviet-source beryllium.
Merckx set the hour record in 1972. On October 25th, he covered 49.431km at high altitude in Mexico City. The record remained untouched until 1984, when Francesco Moser broke it using a specially designed bicycle with meticulous improvements in streamlining. Over 15 years, various racers improved the record to more than 56 km (Chris Boardman). However, because of the increasingly exotic design of the bikes and position of the rider, these performances were no longer reasonably comparable to Merckx's achievement. In response, the UCI in 2000 required a "traditional" bike to be used. When Boardman had another go at Merckx's reinstated record 28 years later, he beat it by slightly more than 10 meters at sea level. On the other hand, Merckx had raced a full road season winning the Tour, Giro and four Classics, while Boardman was a time trial specialist who had retired from road racing and had prepared specifically for the 2000 Hour Record.