----- Original Message -----
>
> Daniel Artley wrote
>
> > Can anyone suggest how I can determine if I do not have a headset of
> > fork that I know are French?
>
French steerers are 25.0mm in diameter, vs the 25.4mm for Italian/ISO. Even the cheapie plastic vernier calipers can measure that well enough to tell quite easily.
If you only have the headset, it will be harder to tell, though I suppose the thread ID should be pretty consistent between the standards.
Jon Schaer
Columbus, OH