Depends on your budget really, for the money, our 460cc engine is unbeatable.
It makes 21.4hp and over 31ftlbs of torque to the wheels!..in stock form. (Add 25% for Engine numbers)
Our engine kit in a completely stock Yamaha G16 achieves 38-43mph on factory 18" tires.
Can you make more power than the 460? Of course, but Ive yet to see a NEW engine that can for the money.
Then again, the 460 has a custom ground cam, higher compression, billet rotating assembly, etc direct from us.