Received from Richard Sachs (who is heading for Italy soon!)
<< data points: - there were 1010b dropouts in 77. - there were rifled seat tubes at least 18-24 months prior to slx/spx complete rifled sets. (Dale's note; these were to reinforce seat tubes for the new-then braze on front derailleur mounts) - the derosas at the 79 milan show were already sporting full mfi made cast lugs-in-the-dubois-style. - that derosa has a cheesey bb shell. - i say mid-late 70s at best, and high odds that it's a mexican benotto.
e-RICHIE©T® >>
Gulp! Passed onto to you,for your further discussion, brethren & sisterns,
Dale
Dale Brown
Greensboro, NC USA