For a quality American or Japanese 4 stroke bicycle motor? I'm not talking about the Honda lawnmower type engines. I'm talking about the Whizzer style engines of the 40's and 50's. A sleek 4 stroke motor that easily fits into the frame of a bicycle. We have a '48 - '50 Whizzer and I'm very impressed at the quality and look of this engine. As we break it in it just keeps getting stronger. I don't have the doubts about this engine that I do when considering the China motors. Yeah I know I could buy China engines all day at dirt cheap prices. But personally for me, adding that motor to a build really cheapens the experience.