Are you running the same fuel mix? Often people run their engine in with a ruch mix and/or a non-synthetic oil with abrasives (i.e. Lawnboy ashless) that contribute to the polishing/seating f the rings/piston.etc...

This causes the black specs.

Some installations you might not see the specs either because of the location of the muffler.

No reason to NEED to see them, as long as you are running a proper mix (either breakin or standard run mix)