Richard Cielec wrote:
>Have need of a GB alloy stem period-correct-not-date-specific for
>pre-1975 Raleigh. "Ish, kind of sort of" lenght is 3 inches +/- 1/4
>in. As good condition as possible.
>I am assuming GB stem & bars are 25mm so, only GB's mate. Any other
>stems mate with GB bars ?
No, GB and other British aluminium (Hiduminium) bars are bog standard 1" (25.4 mm) at the clamp, 15/16" (23.8 mm) everywhere else, just like the ISO standard.
Any normal 1" stem that's not sized for Italian or French bars will fit fine.
The only weirdness of British handlebar sizing is with steel bars. British steel bars were 15/16" (23.8 mm) at the clamp, which is weird, and 7/8" (22.2 mm) everywhere else.
Note that this distinction is based on material, not shape. I own GB aluminium all-rounder bars that are the 1" - 15/16" size, and the steel drop bars on my Lenton Grand Prix are 15/16" - 7/8" size, both of these are the opposite of what you might expect from their shape.
Sheldon "Hiduminium" Brown
Newtonville, Massachusetts
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