Actual measurements of rear dropouts on the following frames: 110mm=1928 Tyler Path Racer,1930's Kinnane Path Racer,1930's Panther(Aust.) 1948 Malvern 5 Star Path Racer,1953 Malvern 3 Star Path Racer,,1930's Whippet(Aust.) Path Racer; 120 mm= 1956 Speedwell(Aust.) Path Racer., 1935 Maino Road Racer. Hope this helps, Art Link,San Antonio,TX,USA
Fred Rednor <email@example.com> wrote: Date: Mon, 7 May 2007 17:15:46 -0700 (PDT) From: Fred Rednor <firstname.lastname@example.org> Subject: Re: [CR]Rear spacing on track/ path/ fixed gear cycles. To: Peter Naiman <email@example.com>, classicrendezvous <firstname.lastname@example.org>
I wish I had a really precise answer, but you seem to have discovered the situation on your own, anyway - which is that modern track bikes use 120mm spacing, and older ones use 110mm except when they used 115mm.
Of course, some (maybe all?) modern keirin bikes are built with 110mm spacing, so there are always exceptions. Anyway, my experience is that all modern track bikes use 120mm (except the aforementioned keirin bikes), regardless of whether they're single sprocket, fixed-fixed or fixed-free. Similarly, it seems to me that the older 110mm hubs (and hence the frames) could be single-sided, fixed-fixed or fixed-free.
My sense, based on the frames I've seen, is that the change from 110mm to 120mm started in the early 1960s and was complete by the 1970s; except for some "atavistic" bikes such as your's, that is. Actually, if you were building a frame to be used with NJS (i.e. keirin-sanctioned) parts, you might still use 110mm, regardless of the era. That might explain your Holdsworth.
I would guess that the 115mm dimension was meant as a compromise, but of course I couldn't say for certain. Actually, the switch to 120mm strikes me as somewhat of a puzzle. The 110mm spacing could handle the various sprocket configurations and surely must also be a bit more aerodynamic. I can't believe that there were so many broken wheels that a change to a wider chainline (and therefore a wider O.L.D.) was required.
Can it really be that as they went to fewer spokes, the sprinters felt a wider hub required? But then, what about kilometer, pursuit and hour-record bikes?
So for me, the question isn't just when, but why?
Fred Rednor - Arlington, Virginia (USA)
> Sorry fellow members. I may be showing my ignorance and need
\r?\n> Question !! Is there a universal standard for rear track
\r?\n> spacing, whether Brittish, Italian etc. I'm selling off my 79
\r?\n> Holdsworth track bike. Rear spacing is 110cm with Shimano
\r?\n> hubs, single side fixed. The buyer has vintage Campag Record
\r?\n> of approximately the same era that are single sided fixed,
\r?\n> atleast that's my understanding and they are spaced at 120cm.
\r?\n> My 1972 Hetchins track bike is spaced in the rear at exactly
\r?\n> 115cm, with a Campag Record single sided fixed high flange
\r?\n> hub. In case anybody is wondering I've double checked all
\r?\n> measurement for correctness.
\r?\n> According to good friend Keith Helon, most single side, or
\r?\n> double fixed are 110cm, and fixed/free are spaced at 120cm.
\r?\n> If more modern bikes did start spacing at 120cm for single
\r?\n> sided fixed, when did this come about ?
\r?\n> Peter Naiman
\r?\n> Glendale, WI