On the other hand, if I want to upgrade from the chinzy plastic of my current shifters (and want to go to a 7 spd free wheel) is there an easy way to tell if the used downtube (or other) shifters I'd be looking at in such a situation are for doubles or triples? I'd imagine they're for one or the other, but maybe that's not so important with friction shifters? If it says dura ace, it's probably only for doubles, right? But what about lower ranges? I see 105, 600, and exage levers on ebay currently that are indexed for 6 or 7 speeds, but few say anything about the chainrings.