Noisy clutch thrust race

[Ncoates]

Having sorted out the clutch disengagement, I've now got another annoyance -  a noisy clutch thrust race. Driving to Prescott and back a couple of weeks ago this got progressively worse, to the extent that on the return journey to London, the race sounded like a loose washer rattling around on a metal bar. Assumed it might be a weak pedal return spring knowing that this keeps the pressure on the clutch pedal, however, lightly depressing the pedal to take up any pre-disengagement slack against the levers made no difference. I also thought it could be a loose race dust cover, but on inspection this appears to be well retained by the peening over of the race body.  The bearing feels nice and smooth with no suggestion that the race has broken up, which would be unusual in any case.... I also oiled the race which seemed to make no difference. One thing I have not checked is whether the starter pinion has been creeping forward, if not secured properly by the spring clip...I bent the clip arms out as they pinion was sticking, so I will do this. I am sure this would not make a constant whirring noise as described above. 

Any other suggestions.