I'm building up an early 90s Colnago sprint frame that I got cheap on Ebay. I have no previous experience with C&V bikes so I thought I'd ask for some guidance from you guys.

It has a 14cm head tube. I want to go with a threaded set up to keep some of the retro look. So the question is, with a 14cm head tube, what length steerer do I need and how much of it needs to be threaded?

One other question: How do I tell if its an English or Italian thread for the BB?

And thanks in advance for any help!

Tubes are typically sized in inches.. common is 1" OD. which is 7/8" ID
metric equivalents 25.4, and 22.2 are same thing..

Has to be threaded far enough to screw the top adjustable cup race down .

If course now , any threading is optional, since 1" threadless headsets are made ..

Italian is RH thread 36mm both BB sides.. a British BB thread is smaller than Italian
drive side is LH thread.

Your fork needs to be at least the length of your head tube + stack height of a headset. More if you want spacers.