Kit comes with everything to Big Bore your motor to a 490.  Piston, rings, and gaskets.  This is one of the ultimate builds we have on the market and preferred by top riders such as Brockstar, Ronnie Renner, and Reigan Seig paired with our Ninja Backup.  It has the same bottom end torqe as the 500 but revs like a 450.  15:1 compression piston with a little extra piston to wall clearence for the Ninja kit.  We are a full engine performance shop.  Ship us your motor in a cooler and we will build it for you with a warranty.  2 week turn around or sooner.  Ask about our 6th gear upgrade, rim polished transmissions, and performance cams.