[Atom] [Brooks] [Campagnolo] [Dia-Compe and Weinmann] [Huret] [Maillard] [Normandy] [Nitto] [SR (Sakae)] [Sachs-Huret] [Shimano] [Strong] [Sansin] [Sunshine] [Sun Tour (Maeda)] [Sugino] [Tange] [Williams] [Dancing Chain] [Saddles]The date of manufacture of a bicycle's components can often be used to determine the date of manufacture of the bike itself.Some bike parts have a date code cast or stamped into the piece.Even those equipped with Suntour Superbe components usually had SR seatposts.
The two sets of Dia-Compe brake lever bodies I checked had the four-number date code stamped inside the lever body (I couldn't find any markings on the levers themselves).However, a Gran Compe set of calipers had no markings. For example, 1182 means the 11th week of the year 1982.For example, the back of cranks are usually marked with crank arm length in mm, typically in the range of 165 to 185.Seatposts are marked with outside diameter, also in mm.Unfortunately, many of these are coded, and require some additional knowledge to understand the code.
If you know of other components that are marked or coded that can be added to this list, please let me know.: The information on this page is copyrighted.This makes dating the components an interesting archeological investigation, but one not necessarily related to the date of the bike. Trek owner Larry Osborn made this observation, and suggested this as a supplementary way of dating a Trek (and other bikes as well).Fueled by this first realization, and with the help of other bike folks, Larry and I have sorted out other codes (a project still ongoing).Especially useful, and challenging to sort out and verify, was the Shimano code.Also gathered on this page are date codes decoded and generously provided by others.The rear derailleur freewheel/cassette and chainwheels are probably the first to be changed on a bike.