Originally Posted by
Bike tinker man
...if you pull the forks out their name maybe stamped on the fork stem.
The Shimano headset should have a date code on it (very small two letters) this (assuming its original) should give you an age bracket, same for the seat post these normally carry a date stamp...
Unfortunately, the original seat post is not preserved.
I just checked the plug, and Shimano Dura Ace - in addition to the stamp 49 on the fork - there are no other marks.
Special notes - оn the left on the fork i find bolt for the dynamo, in the frame there is a hole for the wire (in the upper tube).