This is a REFURBISHED Cayden Cycle BIG Boy BB4 HONDA. 51.00mm (made in Japan)(10-11 to 1 compression ratio) piston kit & aftermarket top end gasket set. See piston comparison in pic #2, OEM piston is on the right side. It also includes a high performance lightweight camshaft (see camshaft specs in pic # 5) & HD valve springs.
This kit will make your bike a 95cc. The cylinder has been professionally bored & honed.