TB Parts Replacement Piston Kit for your 143cc big bore - these pistons also fit many other 60mm big bore kits. Comes with a new piston, rings, circlips and piston pin. These will fit all cylinder heads but if you are running a V2 cylinder head we recommend checking out our TBW1390 piston kit. The TBW1390 is new for 2020 and offers a much better compression ratio for anyone using a 143cc kit with our V2 head.