Big end clearance and indium coating

[kommando]

Initially the soft layer is thick enough to absorb the hard particles and deep enough not to wear the journals, once the soft layer wears then the particles are re-exposed and then they wear the journal. Hence for a roadbike the harder surfaced Al/Sn bearings with a good filter are better than the VP2 bearings as the Al/Sn does not have the soft layer to wear away so it maintains size for longer and the filter takes care of the particles. VP2 in a race bike that is rebuilt yearly with new shells never has these problems and can even but run without a filter as the soft layer is renewed annually.