Ihave a 02 mxz x 600 just had the head shaved cylinders ported and honed crankcase ported new needle bearings in pistons and wrist pins it, and when i put it all back together i added oil in the gas just to make sure it was getting oil through the oil pump. sounds like the pistons are slapping on the walls or on the head so i tore it back apart looked at cylinders no signs of anything head looks perfect no grooves scratches or anythingwhat could be making the noise. PLEASE HELP

I before E except after C.