Big Bore Kit - 44mm Four Port Cylinder THIS IS THE BEST AND THE ... , 5 PORT CYLINDER, EXTREME POWER RANGE GAINS, NEW BILLET HEAD DESIGN, TWO TRIANGLE WINDOWS PISTON, REPLACEABLE BILLET CAPS, 44mm PLUS ADDITIONAL ... TRANSFER DESIGN, COMPLETE EXHAUST PORTING, DOME WRIST PIN, BEARING & CIRCLIPS AND COPPER ...