R
So I have a 2001 summit 600 that I've had to rebuild a couple times. The last time I ordered SPI pistons .020 over as I had my cylinders bored. The sled blew up again and I got to measuring the pistons and their just under 76mm which is stock bore. The pistons say right on top that their .020 over which should be 76.5mm. And inside the piston it has a part number. After looking it up it's for standard bore. My question is why does the piston say .020 on top of the piston but has a stock bore part number and the piston is stock size?