This is a second ebike I got from Alibaba,
This is not the Ouxi v8 or the Voltsteed V8,
This is just call v20. and I believe they are all the same in my opinion.
here is two installation guide videos from two different you tubers.. I also think they are the same bike. I hope these two videos will help someone who bought a similar bike.

voltsteed V8:    • Voltsteed V8 Unboxing and Assembly In...  
ouxi:    • Ouxi V8 or CrossBoss or Voltsteed V8 ...