Originally Posted by
zandoval
I don't remember this lug pattern or component group in the Vicenza/Venito area in the early 70s - Milan had some bikes that looked like this and used by locals for commuting - There were allot of them and I remember the bullet like pattern under the seat - At that time they were going for about $79.00 American - You did not see these bikes on the weekend rides though - If Rossignoli is in Milano then that might be it...
My first thought is that lug types, in and of themselves, are rarely identifiers for Italian bikes, as frame materials in Italy tended to be used widely. This makes sense if you consider that the alternative would have been to have lugs specially made, which few builders could afford. Other build features, or the particular way the materials are used and combined often provides the clues. Of course, particular styles could easily be common to specific regions, as you note. Given the number of makers in Italy, my hunch is that a number of producers could have been the origin of the OP's bike - which is not to say it's not a Rossignoli, only to say that in my experience the lug and seatstay style alone are not often enough to pin down a bike's identity in the absence of other clues.
On C&V, you see a lot of "hey, those lugs look like the one's on my ______ ." This sometimes points us in the right direction, but is rarely definitive, at least when it comes to bikes from Italy.