Is it summit racing on ebay. Break it in the same ratio as your going to run. Billet thrust washer and rm wrist pin bearing. Just make sure to put the piston arrow to the exhaust and the e on the head gasket on exhaust side and take a rag put the 2 stroke oil  that your going to run and coat the cylinder and piston and rod bearing.  Do a leak down test to make sure you have no leaks and if you pass time to start and check the jetting.