This is totally unrelated but at the same time it is related , I work on lots of different stuff, ATV's , UTV's , motorcycles and PWC'S.
Any of this off brand stuff it always difficult to get parts for and the parts are always expensive with very few places where you can actually get the parts from.
In the vid he states those pistons for the KV997 are $300 each which is why he sourced everything he could from somewhere else besides KRASH , I am still trying to figure out what that engine actually is but I have had no luck so far , nothing seems to match up.
The quality of the parts on off brand stuff is usually well below the quality of the big mfg's or aftermarkets mfgs parts , that's just how it is.
Right now I am working on a Coleman 550 UTV with a Hisun engine, the engine is basically a copy of a Yamaha Rhino engine just smaller in CC's.
This has 125 hrs on the machine and the timing chain is worn to the point that the cam timing slipped and it stopped running , the cam chain is $50.00 and is out of stock , it is also 124 links , in comparison the Yamaha timing chain is $40.00 and readily available but it's 126 links, they changed it just enough that the Yamaha parts won't work in the Hisun engine. most likely to skirt the patent laws . not that the Chinese even care about patents .
I have seen Yamaha 660's with hundreds of hours on them , beat to hell and back and the stock timing chain was still kicking along just fine.
Bottom line is you get what you pay for .