Harley-Davidson goes electric

BELLEVUE, WASHINGTON—On June 18, 2014, Harley-Davidson shocked the motorcycle community by announcing an electric motorcycle prototype called Project LiveWire. The Project LiveWire teaser video showed a bike screaming down route 66, emitting a sound that vaguely resembled a turbine. I could barely believe what I saw, so I immediately spent time reading comments about LiveWire—naturally, the reaction was mixed. Some gave props to Harley-Davidson for thinking outside the box; others complained “this is no Harley."

The current trend for all-electric and hybrid vehicles is to assume a “quasi-futuristic,” sci-fi-infused look that pretty much leaves convention and tradition at the curb (think Nissan Leaf). Many automotive enthusiasts don’t see a lot of “soul” or “character” in these appliance vehicles. But enter Harley-Davidson, the company known for its shaking, rumbling, chrome-clad motorcycles that go beyond machinery and extend to a lifestyle. These bikes radiate tradition, heritage, and style. A Harley-Davidson is a Harley because it has a thumping, 45-degree, v-twin, air-cooled power plant breathing through pipes that emit a signature sound. Harley power must be transmitted to the rear wheel via a rubber belt, so now the company may also offer an electric bike. Really? The motorcycle community may need a little time to adjust. And as for my own curiosity about what it would be like to ride LiveWire, I had no idea I would find out just a few weeks later.

Next-generation design

The Project LiveWire engineering team uses all of the latest design, prototyping, and manufacturing expertise that Harley-Davidson developed over the last century of building v-twin motorcycles. I learned about how the LiveWire team engineered and built their ground-breaking electric bike when I talked with lead project engineer Ben Lund. Lund studied Mechanical Engineering and—as you'd expect—loves riding. He's got multiple motorcycles spanning dirt to street.

Like any other “product,” Project LiveWire started out as an idea. Instead of thinking about this new bike as an electric Harley, the LiveWire team started with a clean sheet, setting out to design a great motorcycle that “happens to be electric." Overall, the Harley-Davidson design criteria are simple. A Harley is about the look, the sound, and the feel. So these key concepts would also be at the core of the LiveWire design process.

When you see Project LiveWire in person, you know that you’re looking at something special. It’s forward looking while retaining a balance of design elements that make it “believable” as a Harley. There's no denying it's quite different.

Another thing you’ll notice when you get up close is the attention to detail. Yes, Project LiveWire is a prototype bike, but it looks more like a production machine. There are plenty of interesting and compelling design details to take in, because this project has essentially allowed Harley-Davidson to enter a new arena—the tech industry. Rumbling v-twin motorcycles fit well with heavy industry and manufacturing, but electric bikes are really about technology.

As with anything within the tech industry, timing is everything. Releasing a product six months late could literally mean the difference between millions in profits or millions in losses. In order to be successful with the LiveWire concept, Harley-Davidson set out to execute with speed and precision. More than ever before, Harley-Davidson leaned on CAD and FEA (Finite Element Analysis), leveraging tools like Pro Engineer Wildfire and CAM (Computer-Aided Machining) software to bring the LiveWire concept to reality. The entire LiveWire motorcycle was modeled in CAD before a single part was machined or prototyped. Following the initial completion of the design for LiveWire, it took only four months for a running prototype to hit the track for testing. The elaborate computer model for LiveWire even included optimizations like balancing weight vs. structural strength and durability and advanced wire routing using simulation software and visualization tools. The result was less trial-and-error and more validation and fine-tuning.

Prior to machining and fabrication, some of the parts for LiveWire were 3D printed so that tolerances, proportions, and other attributes could be validated. Harley-Davidson has several 3D printers that run around the clock to validate designs for both ICE bikes and for other projects like LiveWire. The 3D printed parts used for these validation exercises are full-sized 1:1 scale parts, not shrunk down models. This prototyping process allowed everyone involved in the design and manufacturing process to test, fit, hold, and see parts of the bike in proper proportion.

The driveline

Lund's team works on drivetrain components, including the motor, transmission, and final drive. By talking with him about the drivetrain, I learned quite a bit about the heart of LiveWire.

There are two types of electric motors best suited for transportation vehicles: the AC induction type and permanent magnet type. LiveWire is built around a 74hp AC induction motor mounted longitudinally (shaft axis pointing from the rear of the bike to the front of the bike). Lund explained that this AC induction type was chosen because of its broad availability, power density (high power-to-weight ratio), and low cost.

Since the motor is mounted longitudinally, a set of bevel gears is needed to change the direction of rotation so that the final drive belt pulley can transmit power to the rear wheel. When the first prototype of this gearbox was tested, a distinct gear whine was observed. It wasn’t a problem, though—it actually sounded cool. This could align well with one of the key design criteria for Harley-Davidson: the sound. Lund's team tuned the design of the gearbox until the optimal turbine-like whine was achieved.

Project LiveWire is equipped with a Lithium Ion battery pack that’s a (much) larger version of what you’d find in your laptop or cell phone. Producing 300V, this power source can propel LiveWire close to 100 mph, and the rider can choose between an “economy” mode and a “power” mode. Lund indicated that battery technology is one of the biggest limitations in electric transportation today. I asked about range for LiveWire, but that information was not public at the time.

There’s one thing about LiveWire that will be familiar to any Harley-Davidson rider: the belt drive. Lund indicated that in addition to Harley-Davidson heritage, maintenance was a big reason to go with belt drive. Drive belts don’t typically require adjustment beyond the initial service interval when some stretch is accounted for. Belts also don’t require lubrication like chains do, and they are less weight than shaft drive setups. The belt drive is one of the few features that LiveWire has in common with Harley-Davidson’s first motorcycle from 1903.

Experiencing LiveWire

Enough of the design specs, what's it like to ride the LiveWire? I was fortunate to take part in Harley-Davidson’s LiveWire Experience Tour when they came to the Bellevue, Washington, Eastside Harley-Davidson. After signing my life away and watching a brief instructional video, I was entrusted with one of the couple dozen LiveWire prototypes in existence. (I wasn’t at all nervous; I couldn’t wait.)

After running through the “boot up” experience (selecting “power” mode), I let off on the brakes and rolled on the throttle. No clutch, no shifter, just smooth motion. Unlike my Aprilia Tuono 1000R (a brutal streetfighter with 140hp), the throttle response was very linear and forgiving. The bike felt natural, as if I’d ridden it before. At the same time, LiveWire was like nothing I had ever ridden. It sounded exactly like the bike I saw in the teaser video, an effect I thought was exaggerated, Hollywood-style.

Through the course of the off-highway, 20-minute ride, I was able to experience full-throttle acceleration, slow-speed maneuvering, hard braking, and easy-going cruising. For what is supposedly a prototype, this bike was polished. When I rolled off the throttle, I felt regenerative braking that closely resembled engine braking on a traditional motorcycle. The braking was emblematic of the vehicle itself; the ergonomics were just right and felt great.

Will LiveWire remain only a prototype? There were no definitive answers offered that afternoon, so we’ll have to wait and see. But Harley-Davidson has certainly made a bold statement with LiveWire. To this enthusiast, one short ride suggests the company is certainly capable of pulling off a production version of its unlikely concept bike.

Listing image by Courtesy of Gavin Gear