grapeape1000s
04-28-2007, 06:34 PM
ok I'm tearing down a 01 400ex i just bought. my measurements are about 86.40mm on the piston and 86.90mm on the sleeve. I know stock bore is concidered 86 mm. my question. do i have whats concidered stock. i will have the jug bored but i dont know how big i should go. thanks