In a message dated 1/2/2003 3:01:36 PM Eastern Standard Time, classicrendezvous-request@bikelist.org writes:
<< > [CR]Campy bottom bracket codes
The 70 and 68 refer to bottom bracket shell width. 70 is Ital. and 68 Eng. The "P" is for Peista (Italian for track) 120 the over all length of the spindle, I never knew what the "Z" meant but it was dropped in 1978
Kevin Casey >>
Hi Kevin:
You are close, but the 120 does not refer to the spindle length - it refers to the rear hub spacing that the spindle was designed for (this designation was dropped after 1977).
68mm was used for English, French, and Swiss (and in rare circumstances, Italian) BBs. 70mm was generally used only on Italian-threaded BBs (as you stated).
SS is Strada (road) P is Pista (track) C is Ciclocross (Cyclocross, 'natch)
A 65-P-110 spindle is 104 mm long A 68-P-110 spindle is 105 mm long A 68-P-120 spindle is 109 mm long A 70-P-120 spindle is 109 mm long A 68-SS-120 spindle is 112 mm long A 70-SS-120 spindle is 113 mm long A 74-SS-120 spindle is 117 mm long (a rare one) A 68-C-120 spindle is 115.5 mm long etc....
The road spindles got 2.5 mm longer (to 114.5 and 115.5 mm) in late-1977 due to the CPSC-mandated "lip" that was added to the Record front derailleur.
I'm not sure about the Z-mark either, but I think it may have signified a particular spindle supplier perhaps? Or NR (vs. R) bearing shoulder spacing maybe? Anyone know for sure?
Post- NR/SR/GS, the markings got VERY complex for a while (the "SP" spindle being just one of those later-era spindles).
The best place to get all of the gory details is probably in the Sutherland's Manual or any Campagnolo catalog (although Sutherland explains it in more detail).
Hope this helps a bit.
Regards,
Greg "movimento centrale" Parker
Ann Arbor, MI USA