TB Piston Kit, Forged, High Compression, 63mm – KLX140 TBparts new forged piston! The next level of performance and quality. Forged pistons offer more strength and are more resistant to wear. This brand new FORGED 63mm (170cc) high compression piston kit was developed for use with the stock cylinder head. This is a replacement part for use with our 63mm 170cc cylinder. Complete piston kit includes the following: Piston Wrist Pin Ring Set Cir-clips Compression ratio on this piston is: 10.9:1 – 170cc bore kit combined with the OEM cylinder head 12:1 – bore kit w/+6 stroker crank 188cc Fitment: Kawasaki KLX140 In both combinations above, high octane pump gas can be used (Race gas is not required).