Das ist die OVP von meiner schwarzen. Vlt sieht ja jemand Anhaltspunkte, durch die man auf das ungefähre Produktionsjahr schließen kann
EDIT: Meine SR Teile haben im Gegensatz zu Suntour oder Sugino keinen Date Code. Jedenfalls keine meiner Vorbauten oder Stützen haben einen, meine Kurbel auch nicht (alles Royal EL oder SEL). Aber hier gibts etwas Aber ich finde reichlich unpräzise, besonders für die Royal Teile:
Zitat/Quelle: http://www.vintage-trek.com/component_dates.htm
SR (Sakae Ringo and Sakae)
Code 1
Below the insertion mark on SR seatposts (and Sakae posts) is a stamped mark, such as F-84. The number is the year of manufacture and the letter appears to be the month of manufacture. In the example, the "F" indicates the sixth month, or June.
Steve Mann reports a mid 70s SR seatpost which is marked with a date code of the form 76.9, where 76 is the year and 9 is either a fractional year or the ninth month of the year.
Most SR right crank arms also have an open date marking, either stamped or cast into the arm. The date is on the back side of the arm near the spider of the crank, typically of the form of the two-digit year above a letter, apparently representing the month.
An SR Custom crankset, reported by Alan Burnett, has the back of one arm marked only with a 1 and the other arm with a 2. This crankset came on a 1982 Trek 412. Alan suggested, like for Campy crankarms, these are the last digit in the year; i.e. 1981 and 1982.
Mike Marro reports the crank arms marked "SR Motobecane" (no other model name) on his Motobecane Grand Touring has the following:
Left arm: 77 J (in a circle) (Oct 1977?) and a 3
Right arm: 78 I (in a circle) (Sep 1978?) and a 1
Mike writes: "This might discount the idea that the stand alone numbers represent the year seeing mine have a year code stamped additionally with the numbers." Does anyone have a similarly marked set of SR cranks?
SR stems usually are marked with the same date code. It appears near the insertion mark.
An exception is the SR Royal stem, most - or all of which, have no code.
Most (all?) SR handlebars have the date code stamped near one of the ends of the bar.
Code 2
Rodney Dickinson has identified two other forms of SR date codes. He writes: "Earlier bikes with SR cranks seem to have a different numbering system, like (9-6) or (8-10), which do not have an obvious match. I recently learned of the Japanese Showa calendar, which might provide the answer. For example, Showa year 49 was 1974, hence (9-6) would be 1974-April. Showa year 48, stamp (8-2) would be 1973-February."
Code 3
Rodney continues: "Another problem arises when presented with a date stamp like (23/9C) or (I3/10). These could be the in-between years of transition between the Showa and Western calendar. Need more samples."