Gp1200 65u race ported cylinder, has big bore sleeves in it, one sleeve will need to be replaced advanced sleeves still makes them, also talked to tim judge about it and he said others make them also, your cases will need to be bored to run this cylinder because the sleeves are thicker for the bigger pistons it is setup for 86mm wiseco pistons other two sleeves are in perfect condition asking 300 plusactual shipping