On Thursday Harley-Davidson unveiled Project LiveWire, a nationwide tour to introduce company’s first all-electric motorcycle. LiveWire is a prototype, to be precise, with few specs beyond a 0-60 in fewer than four seconds and no word on if and when it’ll be a real product. Still, the legendary American company’s entry legitimizes this fledgling part of the industry, in the same way that BMW and Mercedes-Benz’s new electric vehicles lend some cachet to the econoboxy EV market. The buzz started Wednesday, with an enigmatic video on YouTube. It’s a cool, misty morning. The camera pans slowly over an empty strip of asphalt surrounded by grassy fields, then past an old, tin Route 66 sign. Suddenly a motorcyclist flashes by, and that sound, what was that sound? Not the hawg’s classic growl, but a higher-pitched, jet-engine-like scream that wouldn’t be out of place in the Tron: Legacy movie.