BBR 411-KLX-1401 143cc Big Bore Kit with Cam. Bolt on and go; BBR offers the largest displacement bore kits available without the need to bore engine cases. Complete kits include aluminum plated cylinder, BBR motocross-grind camshaft, piston kit and gasket. Add 26mm Carb Kit for the best performance gains. Bore Size : 60.00 mm.