Bicycle Mechanics - Headset Tightening?

So I recently got my frame repaired and etc etc and I put together back the headset and fork. It's an older headset, specifically of an 89' Bianchi and is a little different from maybe newer ones people might be more accustomed to. Anyways, took it for a ride and whenever I move the bars/turn/steer a little more than a few times, it gets really tight to the point where I can't turn the bars anymore. Anyone know what the problem is?

Do you own a headset wrench? It's like a 32mm cone wrench.

After adjusting the bearing preload you have to snug the locknut up against the headset cone pretty tight. If you don't have the right wrench to hold the headset cone, it'll turn and won't be able to hold the adjustment.

Assuming it's a threaded headset, you may have tightened the top adjustable cup and locknut too much. It's a very fine line between too loose and too tight. If it's binding, you need to loosen the lock nut, then the top adjustable cup a hair, then with a wrench on the adjustable cup to prevent it from moving, tighten the lock nut. Make sure it moves freely without any indexing, but isn't so loose you feel any play.

http://i32.photobucket.com/albums/d7/k4drd/Bicycles/Headset.jpg

Nice diagram above. Also, make sure that the top locknut is tightened down fully to the adjusting locknut or you may have issues out on the road or trail with the headset coming out of adjustment. 32mm and 36mm are the most common sizes for headset wrenches.

Ah, I see.

thank you for the prompt and useful replies, especially the diagram.

After lunch with my dad, I'll be taking all of your advice and see if I did anything wrong.

http://www.parktool.com/repair/readhowto.asp?id=127