Ron Gurth wrote (and I <snip>): My girlfriend, Deb, who is rapidly converting to CR-ism, is restoring her '83 Schwinn LeTour, a really nice machine (that is one of the 'good events). It has good (though 'mid-range) Suntour mechs, with aero-style downtube shifters that mount to the top side of the down tube via a single bolt. There is a two piece 'shaft' connecting the lever mounting points, with a cam that moves the left lever when the right lever is pulled. Frankly, after we disassembled the thing and cleaned the gunk out, I am not 100% sure I reassembled it correctly. and the left lever feels a bit loose. And what is the purpose of the connection between the levers?
Harvey: The connection is very clever: as you pull the right lever toward lower gears, it slides the left lever backwards, slightly loosening its cable. This, of course, moves the FD to the left, so it tracks the chain angle. On mine it doesn't seem particularly effective, but it is sort of a Rube Goldburg approach to keeping a narrow FD cage while avoiding having to adjust the FD with practically every shift. The best single reason I ever saw for the top-mount DT shifters.
Thanks,
Harvey Sachs
mcLean va