Yes and no. The two have the same diameter and pitch, but the thread angle is slightly different. In practice, this means that an English HS works OK on an Italian steerer, but an Italian HS will be tight on an English steerer. You can install it with additional force, but you may damage the HS or steerer thread a bit in the process. At least this is the case with Campy NR HS's. Depending on manufacturing tolerance, I suppose it is possible some Italian HS's might go on an English steerer without undue force.
Regards,
Jerry Moos Houston, TX
Nick Zatezalo <nickzz@mindspring.com> wrote: Can a British threaded headset be used on an Italian threaded fork and vice versa?
Nick Zatezalo
Atlanta,Ga