If your machine has been standing without protection from rain and moisture over an extended period, it is likely the grease that this item was packed with has been washed away, leading to pitting of both the cone, the bearings and probably the race as well. It would be sensible to replace the complete assembly, and ensure your steering is free of play and at the same time not tight and stiff to the point where the handling is adversely affected! For all the parts you need to complete a satisfactory head stock overhaul, access the online 'parts list' fiche, where applicable or the online catalogue for your model.
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