Jonesy
I cleaned and cleaned my carbies trying to get them to idle and behave.
In desperation I tipped a whole bottle of injector cleaner into half a tank of fuel (it said on the bottle that you can't over treat it by doing so)
The thing has run like a charm ever since.
I guessed it was old fuel residue on needles and jets etc that's pretty well impossible to clean out by mechanical means.
A more conservative approach if you were concerned about my method would to be soak various bits in the stuff but that would entail stripping the carbies.
The first method worked for me though.
