I'm not certain, but I think 120 indicates that these spindles will position the crankset to achieve proper chainline with a 120mm / 5-speed rear hub. It's all a little wierd though, because as far as I know Campy never simultaneously made different spindles to work with 120mm / 5-speed and 126mm / 6-speed rear hubs. They made the 68-SS-120 (or 74-SS-120) then they added some length when the CPSC changes were made about 1977. These were marked 68-SS-120 along with +1.0 / +1.5. Later they were just marked 68-SS. By this point the standard for rear hubs was 126 and the post-CPSC BB's are suited to such use. In any case there are definitely pre and post-CPSC spindle differences, and one would be lead to believe that there are also 120 / 126 spindle differences, though none of my observations suggets that this actually happened. In other words, if you have a pre-CPSC crank use a pre-CPSC BB and it should work with either 120 or 126 rear hubs. If you have a post-CPSC crank use the newer BB and it too should work with either type of hub. Confused yet?
> I saw the recent thread (2 messages) on campy
\r?\n> spindles. However,
\r?\n> I still have questions. I was recently given a box
\r?\n> of old bike
\r?\n> parts, among them several spindles in pretty good
\r?\n> Two of them are labeled 74 == SS == 120. I was under
\r?\n> the impression
\r?\n> that the SS or middle code indicated the length and
\r?\n> a certain
\r?\n> kind of offset when the spindle had different
\r?\n> from the bearing race to the end for each side. (I
\r?\n> came by
\r?\n> this info via an old catalog from Loose Screws). The
\r?\n> don't measure 120 in length (unless I'm not supposed
\r?\n> to measure
\r?\n> end to end for this). So my questions are am I
\r?\n> about the SS part, and therefore what does the 120
\r?\n> BTW, because these are 74's, I don't need them. If
\r?\n> wants/needs them, I'd be happy to trade them for
\r?\n> anything else. I have two, so I guess I could trade
\r?\n> to one
\r?\n> or two people.
\r?\n> Please include email@example.com in your reply. Thanks.