Kevin Kruger wrote: <snip> Again, I suspect that the Campy downtube shifters were replaced with the Suntour barcons, although I recall these barcons were commonly used on Paramounts (primarily P15s since Campy barcons have a tough time handling a triple crank with a Record front derail.). May have been done at the time of purchase by the Schwinn dealer who sold it??? ++++++ As I noted in an earlier post, the Suntour "Schwinn-Approved" Barcons were a factory Paramount option starting in 1973. But, I can add a bit to the statement that "Campy barcons have a tough time handling a triple crank with a Record front derail."
Quite a while ago, I measured the "capstan" diameters of a bunch of DT and bar-end shifters. After all, the wrap diameter determines how much cable is taken up. Although they aren't perfectly cylindrical, my best estimates for the Campy were 20 mm, and the Suntour came in at 23 mm. So, a given angular throw would move the cable 15% further with a Suntour than a Campy. This tends to confirm Kevin's statement. Conversely, on the back end, the Suntour gave shifts that were rather closer than I like with some rear derailleurs.