"Creaking" noise from headtube/handlebar I have a steel frame (Columbus steel, made by Dancelli), and when I put weight on the ends of the handle bar, I hear a creaking noise from the headtube. It might not be the handlebar because I tried applying force on the headtube while holding the top tube and I heard the same creaking noise. I can't pinpoint where the noise is coming from ... is there a way to find that out and fix it? Many thanks!

After disassembling the front assembly, as per Carel's and Davorin Ruševljan's suggestions, I found out that the fork tube (going through the headtube) had a crack in it, which is most probably what was making the creaking noise (see picture below).

!enter image description here