Cam bearings

[sean_rfi]

Hello All,
I found on dismantling my Z900 engine that a number of camshaft bearings had what appeared to be blisters or small raised lamps on them.
I applied pressure to them and they feel like solid metal. There does not appear to be any noticeable wear on any of the bearing surfaces.
Has anyone else seen this before and are they still serviceable or should I bin them?

Thanks in advance,
Sean

[zed1015]

Iv'e got loads like that.
Never caused a problem.
May be caused by gassing between the two layers.

[kev edwards]

That's probably caused by contamination during build up proccess, got some old ones that have different colour spots where its happened, never had running problems though.