Harvey,
There are two primary lockring thread sizes that are in use - still today, and apparently this has been the practice for at least 30 years, but only people who try to move parts between different brands of hub are likely to notice - until they lose a ring and buy a replacement of the wrong size.
33.5 mm x 24 tpi left-hand thread ( Campagnolo compatible ) - which is also used by Phil Wood, and a few other manufacturers.
1.29" x 24 tpi, which is used by Shimano, Suntour, Suzue, Hed, Corima. This threading was also for the '80's Japanese "Sunshine" hubs which where a copy of the Campy hubs in most respects except they didn't use Campy's threading.
Since 33.5 mm is 1.319", the Campy rings will fit (loosely) over the lockring threading on the Non-Campy sized hubs.
Ben Sanford Falls Church, VA
[CR]Fixed Gear Lock Ring Threads Vary
To: classicrendezvous@bikelist.org From: "H.M. & S.S. Sachs" <sachs@erols.com> Subject: [CR]Fixed Gear Lock Ring Threads Vary
This is a bit esoteric, but may be important to some folks: There is more than one "standard" for lock ring threading for fixed gear hubs. I was trying to fit a lock ring to an "FB" (Italian) hub this morning, and the first rings I tried just wouldn't fit. So, using the hubs available, I did a bit of measuring. Sure enough, I got the following results (where I'm using lines of dashes to let you know where the line breaks are, since this can get messy with email):
F.B. (Italian): 1.313" (33.4 mm) ----------------------------------------- Harden (G.B.) 1.290" (32.75 mm) ------------------------------------------ Paramount (US) 1.305" (33.2 mm)
The Paramount hub barrel has been rechromed, so I suspect it is the same as the Harden, and that this is a "British Standard." I did not check the thread gauge, since threading on seemed no worse than class B (will work, but doesn't feel perfect).
The one lockring I found that did fit the FB was real loose on the Harden (sort of like a 14 mm pedal in a 9/16" hole). If you find such loose fits, I would not recommend using them if you count on the lock ring for braking.
I don't have a Campy track hub to check. There was no info in Sutherland 2nd Ed, the only one I have.
Your mileage may vary...
harvey sachs
mcLean va