Even those equipped with Suntour Superbe components usually had SR seatposts.
Many components are marked with size descriptors in addition to component manufacturer's date codes.
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.
The rear derailleur freewheel/cassette and chainwheels are probably the first to be changed on a bike.
This can be simple like "0784" (month 07, 1984) or a clock-type, with year in the middle and a ring of numbers with a tickmark pointing to the month.""Dia-Compe road levers usually have a code stamped _inside_ the lever.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).For old Treks, 27.2 is the most common, but for other bikes the diameters can range from 25mm to 33mm.The rear derailleur can often be dated to a year or two by referring to the book "The Dancing Chain - History and Development of the Derailleur Bicycle", by Frank Berto, 3rd edition 2009.Dia-Compe cantilever brakes don't appear to have a date code, but supposedly the 981, 983, 986 brakes were first introduced in 1981, 1983, 1986, etc.