Copyright laws state that "an item must be at least 10% different from any other available item"; that being said, 10% in cosmetic changes is easy to achieve &, you would think, would satisfy the copyright laws so, there's no need to modify the internals...
An associate of mine recently purchased a GX200 clone; the first thing he did was tear it down & then noticed that the conrod (apart from other parts) was stamped with the Honda logo, proof that Hondas & clones are made in the same chinese factory; it's entirely possible that every clone engine is, in fact, a Honda reject, Honda take the best of the best & the rest are sold by the manufacturer; whether this is the case with Lifan or not is anyones guess...
Also, as stated by KartFab, the 200 clones are the same & the 20hp twins are the same so, you would think that everything in between would be the same too, however, that is merely supposition...
The best advice I can offer is check the bore & stroke of the Lifan against the bore & stroke of a Honda; if they are the same, you can assume that everything else is too...
