Wonder who's making this one? i can't find any Loncin engines in 224 cc's
Did you watch the video ?
Ducar makes the engine
Ducar is the 4th biggest engine maker in China.
It is a big step up from the Loncin engines sort of like the difference between B & S vs Kohler .
The "strengthening" ribs on the crank are most likely there to control flow in the die when casting and the ones on the block are there to prevent fin ring & control air flow to make sure all of the fins are doing their job .
Fin ring has long been know to generate a lot of noise and now days most air cooled motorcycle engines have either a bridge on the fins or rubber jambed between them to dampen down the sound.
Hazarding a guess would be Loncin can not keep up with demand, particularly with the demise of B & S so smaller companies like H F had to source supplies elsewhere .
Parts for Ducars that are not direct Honda swaps are even harder to come by than parts for Loncins.