I just bought a Schwinn OCC Stingray Chopper. It has the 48cc Chinese motor. I love to tear things apart modify them and put them back together again so I have ordered another moter that I will fix up to replace the one thats on it now even though it runs fine. That way I'll have a spare. I intend on needle bearing it, then adding the Manic Mechanics Gen II head. Of course I will port and gasket match the whole thing and balance the engine and then use Prolong for better break in. All I'm looking for is much less vibration and smooth power. If you run across any good after market parts give me a heads up.