Re: This not-whizzer looks interesting
Welcome to the forum.
First, let me say that Whizzers, while expensive and kinda fancy, are not all that reliable, and have a lot of QC and reliability problems of their own.
Second, the type of bike you show, with a Chinese engine kit, are not all that bad if properly set up/built. The hub adapter is non-standard issue, and much better than stock, although the chain is a bit too tight.
Finally, I don't know what kind of motorcycle the third picture is...