Honda Mini 4 Strokes
this engine is underpowered. over weight though? well... 3.8 Lbs. is about 8 ozs. heavy. I have a 31cc ryobi with C & H ignition. power to weight is VERY good & it weighs 3 lbs. (with some of my very extensive trimming). there is a 50cc version called the GX50. I'm going to take this one on as a project & boost the compression come hell or high water. that's its' fatal weakness... 7 to 1 compression ratio. I'll keep ya posted