At 9/11/2006 09:56 PM -0400, Bradford Riendeau wrote:
>To add to what has already been said, the changeover was part of a
>movement in the early 1970's to establish ISO standards for bicycles.
>Fred DeLong who wrote for Bicycling chronicled the process at the
>time. If I remember correctly, English steerer tube (25.4 o.d .and
>22.2 i.d. aka 1 inch and 7/8ths), bottom bracket (1.37 x 24 tpi)
>and freewheel threading won out (1.37 x 24 tpi), in part because
>there were also the Japanese standards. The only standard that
>didn't fully stick was the stem pinch bolt standard of 25.4. The
>industry standard for road bars stuck with the Italian 26.0 until
>recently, although 25.4 is standard for mountain bars and a lot of Nitto stuff.
It's been a long time, and the brain cells are dying off ever faster, but; I seem to remember that the standards committee had two other recommendations that never got much traction.
One that never was taken seriously, was that pedal threads should be 1/2".
The other was that front hub "over lock nut" spacing should be 95mm. I believe some manufacturers may have retooled to meet this. I've found several front hubs from that era with narrower than normal bodies, and either spacers or very thick locknuts to bring the width out to 100mm.
These are very handy for building a "Modern" front wheel for an old Moulton or English 3 speed. (I'm well equipped to do a proper job of respacing frames and forks, but I prefer not to.) With carefully chosen cones and locknuts, I've gotten width down to 90mm or so.
If I've misremembered any of this, I'd welcome more solid info.
Mark Stonich;
Minneapolis Minnesota
http://mnhpva.org
http://bikesmithdesign.com