Right now there are some Chinese engineers reading through this thread trying to keep up with your build, waiting for you to post the next step. While their numbers crunchers are trying to figure out what the cost will be to get this project into a manufacturing mode.
Dogcatcher I'd be flattered if they are and surprised if they're not.
Business is more akin to warfare than to gaming in many countries. In 1978 I took a working prototype and exacting performance parameters to South Korea for bid which included the final production design, product testing, quality control, warranty assurance etc. In ten days time they returned an initial bid package that was 50% under our best minimum bid estimate and 20% under the nearest competitive bid's final number. We negotiated with them for over a month & received an addition 15% off in ancillary costs involved in shipping, insurance and any extraordinary delivery delays. It was a dramatic business experience for me and quite profitable, but in subsequent business dealings I learned a lot about their manufacturing capabilities and resolve. I now believe they could have turned a nice profit at 15% less than was actually paid per piece. I'm certain they felt they had screwed me hard. This was a major Korean company with state of the art design and production capabilities that I'd never before seen anywhere.
Fast forward to today and real quality enhanced production has spread throughout the Orient. If we can dream it they can build it for less.
I've heard talk of Oriental junk (some was and is) since the fifties and I still hear it and read posts on this forum that repeat it, but don't think they can't and won't build quality products and do when we are willing to pay a little extra for that quality and yes they will steal your dreams before you even go to sleep...this is war to them, not a game. We laughed when first Honda then Suzuki etc. started importing this "made in Japan junk", but price, styling, performance and dependability shut down, those who couldn't & wouldn't compete; mighty U.S. and European cycle manufacturers out of the business in less than ten years.
I'd hope we would learn from the past, but it's easier to rest on our ancestry's laurels. The bottom line is if the Chinese ever do manufacture classic style motor housings they will be much less expensive and more readily available for those that want the look of classic and the sound of silence on their e-bikes. Ride on and have fun!
Rick C.