Golden Eagle makes the other kit parts themselves (in the USA) but they don't build their own engines.Golden Eagle Bicycle Engines are all USA, and I'm not sure about this one.
Ridley Vintage Motorbikes : Vintage Motorized Bicycle Kits
The Ridley engines look just like the usual China Girl setups.
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This "buying American" is almost a lost cause when it comes to buying bicycles. Worksman is about the only way to go, for anything like a cruiser-style bicycle. And that's a very limited choice, considering that the largest Worksman frame is still quite a bit too small for this adult.
Most bikes and bike parts are made in China now, and most of the rest are made in Taiwan. Buying a vintage/used bike (even from a US manufacturer) prevents a few dollars from going to the Orient, but it doesn't do much to preserve US jobs now.