This is a motorbike that began its life somewhere across the Atlantic Ocean, immigrated to Tennessee, sat in an old barn for many years before it was rediscovered and brought up to Manhattan, and purchased by a Monmouth County guy who loves restoring these sorts of things.
I believe it is a Nazi WWII vehicle. The restorer found that the original colors were the tan and white of the Africa Corps, so he is restoring it as such.
Because parts for motorbikes of this age are so difficult to come by, it is a Frankenbike of sorts, with few original parts and many bits from China, Germany, Africa, the USA, etc. etc. etc.