oachs83
09-07-2009, 06:29 PM
I only ripped the head off my 86 250r to see the size piston I need so I can order the parts. There is a number on the top of the piston. The number is 3890J but I can't cross it through google. Also I put a micrometer on the cylinder bore through the top and it reads 2.655" which comes to 67.437mm. But the closest Wiseco has is a 67.5mm. So what size piston do I order? Thanks