If we're listing our 'creaks' I just sorted one out yesterday.
It started just after I replaced my rear wheel with one I had built myself, and took the form of a roughness when pedalling or back-pedalling. The derailleur could be seen doing little 'jumps' in concert with a sort of repetitive 'clicky' noise. I couldn't tell if the noise was coming from the BB or rear mech.
To cut a long story short, I hadn't tightened the cassette-ring quite enough when fitting the cassette to the new hub! A quick, easy fix for once!
