Originally Posted by
unterhausen
that's not a '78 headbadge, they were attached with screws back then. Not sure when they switched to the glued on headbadges. That's one way I know if it's possible I built the frame.
My new guess is '83. All models had the cable routed below the BB, the head badge got glued from 81 on and the only part of the serial number designating the year I can see is a rounded curve near the bottom.