a large, off center weight mounted to the end of an electric motor shaft, centrally located somewhere under the seat with the speed controlled by the throttle should work. of course, you'd have to sync it with some sort of obnoxious, amplified recording of a real Harley engine. on another note, does Harley only employ blind design engineers? fug that thing is ugly. i'd have just stripped down an XR1200 and bolted all that electric garbage to the underside of that platform. you ain't ever gonna get a more aesthetically pleasing Harley than that bike.
Aluminum frame, proper mono-shock swingarm? I say good on HD for trying to modernize. Y'all can hate on it all you want, I think it's refreshing to see that company playing outside their sandbox. That said, their demographic will not be lining up for one.
So where do you put the oil for it to leak out? I guess now you just have to dump a quart of oil on the floor of the garage and park the bike over it.
So just under a metric shit ton? I'm ok with it except for the horrible front brake caliper and the horrible rear fender. Everything in between those isn't all bad.