Originally Posted by
Trakhak
As I understand it, grease consists of oil suspended in a soap-like matrix. The oil can and usually will migrate out of the soap over time, as seen, for instance, in the ring of dirty oil visible on old bicycle hubs at the axle.
Interesting info. All the vintage BB/hubs I’ve encountered over the years usually exhibit one of two conditions: thin dark oily residue seeping out, or thick whiteish-brown caked residue in the cups/retainers. The latter has always appeared to be original, and I assumed the thin stuff had been ‘topped off‘ by PO with some unknown lubricant.
Would different types of grease produce different signs of age/breakdown? Or is the liquidy appearance just an intermediate form along the way to caking up?