Material in oil filter after rebuild

[Thoglan]

I am about 8,000km in since rebuilding my engine. I am still getting the odd small fleck of metal in the filter. The motor was rebuilt completely top to bottom. New rings/hone, rebuilt head etc. I took a photo of the filter that I took out most recently (about 1000km on it). There were 4 or 5 small flecks in the whole filter as shown below.


What amount of material is normal for these engines? I would assume none, especially after a rebuild. I did notice peering through the oil filler cap that there seems to be some unusual wear on one of the cam lobes. These are original and were not replaced in the rebuild. Again, is this normal? Could it be the cause of the occasional material in the filter? Worth removing the cam cover to take a closer look?

[cobra]

I would expect a piece of dirt here and there unless you built it in a clean room.

I've seen that type of cam wear before, it doesn't seem to be a problem long-term.

[Syfon]

FWIW OP, I rebuilt my motor and got it running about 6 months ago. Have since covered ~4,000km and many oil changes.

Most recent oil change had ~1,000km on it. I opened up the oil filter and saw a few non-ferrous metallic particles just like yours.

With each successive oil change, metal particles seem to be decreasing.

I had a local machine shop clean/flush/etc. the block & head. It's anyone's guess how well they cleaned everything; especially the oil galleys in the block. On this note, I pressure cleaned the oil galleys in the crank, and a lot of shit came out. Likely the machine shop didn't clean all components correctly!

Mind you, I did rebuild mine due to a spun bearing. There was a lot of metal inside my motor when I opened it up