Originally Posted by
Kevindale
The FD has the date code 'OH', Aug. 1972. Both cranks were marked '47-8' and '171.' Did they make a 171 mm crank?. Couldn't find any code on the RD.
Thxs, the crankarm codes are also August 1972 so it's almost certainly a 1973 model, though the frame could have been manufactured in late 1972.
The dies for those cranks were designed to imperial measurements. In this case it's 6-3/4". 171mm is the metric equivalent, rounded to the nearest millimetre.