Yes, now I think about it - silly me, even the big end area is reciprocating mass. I suppose I was thinking it was just as much a part of the conrod as it is the piston. But it's adding to the conrod, so it's part of the piston mass that the conrod has to move. Those figures for the 440 pistons and pins are huge compared to the SRP weight of 462g. But it's good because I'm starting to get an awareness of weights now. I know the old TRW forged were pretty heavy (even though they could take huge punishment) and that stopped a lot of racers of the day using them.