Just got the rings onto my new proX piston for my KDX and am curious about something. Both rings are exactly the same size but the top ring fits snug around the piston while the bottom on is loose like the OEM one that I am replacing. Is this normal or is there something wrong here?

anybody know anything about rings?

Yes, there is generally a top and bottom ring.. The top ring will usually have a small indentation toward the end of the gap, or the ring will have a taper when viewed from the end of the ring gap. If the ring has a indent in the top that goes up.