Here is the complete engine top proposed by ATHENA to rebuild your HONDA CRE and CRF 250cc 4 stroke from 2004 to 2009. This kit is sold complete as on the picture with its axle, clips, ring, piston, gasket and cylinder. This kit is not a big bore. It has the same characteristics as the original. You will not have any gain of performance on your motorcycle has by the refurbishment of it. It is of course of excellent quality as usual at ATHENA. The nikasil is really excellent to guarantee you an increased reliability.