My MC28 has 46,000 km on its first cylinders. The pistons reportedly have been changed after 30,000 km.
When checking the cylinder/piston compination I noticed that the "A"-cylinders are combined with "no mark" pistons. While such a combination probably is not prone to seize, the piston-cylinder clearance is definitely not within spec((for new parts).
I wonder what the downside of such a combination is. Reduced compression? Faster piston and cylinder wear because the piston has more room to move inside the cylinder? Reduced ability for the piston to transfer heat to the cylinder? ???

I should probably change to "B"-pistons after having the cylinder checked, right?

What do others think?

If the piston slaps around there is danger of shattering the piston skirt. Especially if you over rev it. Nasty

Good point. Thanks.