Originally Posted by mswantak
On head lugs, yeah. Knowing that angle can provide useful information about the steering geometry. I'm not so sure how important it would be to know the angle of the seat tube though.
Well, my Puch Mistral was made in the 80's and the Bocama seat lug is stamped 74.
http://www.classicrendezvous.com/France/bocama_3.htm