MVVS 58cc gas
I took a look, since I have a 1.6 & a 2.15. The 58 is rear intake & looked good to me until I realized it has reed valves. I don't care much for reed induction.
The engine will compete directly with the ZDZ 60cc which has disk induction, a thing I believe to be better than reeds.
My .02,
CR