25 grams. Bout the weight of a sack of weed. Not a whole lot. Yeah, slingin around at 6K it's a little bit, but it can be made up somewhere else. It's not the end of the world for sure. There ARE actually advantages to a heavy piston. I wouldn't worry about it too much. Lots and lots of engines were built and very successfully with those "old boat anchors" lol.