TThere’s a buzz within Cycle World headquarters lately. The hum of electric motorcycles charging during the workday can be heard in the halls as staff members have plugged into the merits of two-wheeled EV transportation. Whether zapping to and from work or effortlessly whistling about the greater Los Angeles area without so much as pulling a clutch or toeing a shift lever, EV bikes have proven to be a viable mode of urban transportation.
Enthusiasm has been recently supercharged with the simultaneous arrival of the 2020 Harley-Davidson LiveWire and Zero SR/F Premium, a pair of preeminent models within the segment and the natural makings of a heads-up comparison.
These full-fledged roadbikes are each endowed with chassis specifications, ergonomics, and styling well in line with a contemporary petrol-powered liter-class sport naked. Both feature comprehensive IMU-based rider aids with lean-sensing traction control and cornering ABS, and have selectable ride modes for Sport, Street, Rain, and Eco that tailor throttle response, peak power output, regenerative braking, and TC sensitivity. Both have a TFT dash display providing a wealth of info to monitor charging status, estimated range, state of charge, ride mode selection, and more.
The physical size and load capacity of these bikes facilitates use of a larger lithium-ion battery pack than any EV motorcycle we’ve tested in the past. Each bike’s power pack is encased in an aluminum heat-sink housing, lending a stylistic appearance along with the strength and rigidity to serve as a stressed member of the frame. Zero employs a tubular steel-trellis frame wrapping its 14.4 kWh Z-Force battery unit, while Harley’s frame structure is composed of aluminum-cast members bolted to its 15.5 kWh Rechargeable Energy Storage System (RESS) that join at the steering head.
While both are propelled by an interior permanentmagnet brushless AC motor, their powertrain configurations are fundamentally different. Zero’s ZF75-10 motor is a passive air-cooled design mounted with its power shaft horizontally across the frame, using a final-drive pulley attached directly to the motor’s shaft. The Revelation motor of the Harley-Davidson resides beneath the RESS in a longitudinal arrangement, features a liquid-cooling jacket, and employs a gear-ratio-reducing spiral-bevel-gear primary drive that transmits torque to its perpendicular countershaft/sprocket arrangement.
Measuring power output at the rear wheel on the Cycle World dyno revealed an interesting contrast in engineering approaches. Viewing each bike’s peak torque value alone would lead one to surmise that the Zero’s 146.5 pound-feet flat buries the 74.2 pound-feet of the Harley.
Not so fast, Buzz Lightyear.
First, note that the LiveWire motor spins beyond 14,000 rpm, while the Zero tails off around 7,000 rpm. Horsepower produced at higher revs mathematically equates to notably less torque than when the same horsepower value is produced at a lower rpm. Comparing the two at a dyno drum speed of 55 mph, we found the Zero produces 80 hp and 120 pound-feet at 3,500 rpm, while the Harley dealt 91 hp and 68 pound-feet at 7,000 rpm. It’s much like your classic gas-powered matchup of a biginch twin and high-revving inline-four. Harley-Davidson’s role reversal of leveraging revs while the competition leans on low-rpm torque truly is a Revelation.
Tipping our scale at 502 pounds ready to ride, the SR/F Premium would also appear to enjoy a power-to-weight advantage on the 544-pound LiveWire. The Harley has 8 percent more energy storage capacity, however, justifying the additional pounds, which also pencils out at 8.3 percent.
Putting rubber to the road at our test facility, the acceleration runs measured with a VBox GPS datalogger provided more surprises. The LiveWire sprinted the quarter-mile in 11.54 seconds with a 110.63 mph trap speed, putting the Zero in its mirrors with a best pass of 11.83 seconds at 116.2 mph. Comparing trap speed is a telling clue the LiveWire accelerates quicker, flexing shorter overall gearing that’s clearly illustrated in the comparative zero-to-60 mph time. Here the LiveWire’s 3.12-second showing crushes the Zero’s 3.65-second zero-to-60 time and accounts for the overall ET. The LiveWire also narrowly edges the Zero in measured roll-on times from 40-to-60 mph and 60-to-80 mph, a performance metric in which both bikes easily beat the top-gear acceleration of every gas-powered bike Cycle World has ever tested. To be fair, however, it’s an apple-to-oranges comparison; toe a literbike down a couple of gears and see who bears fruit.
Seamless, nearly silent acceleration beats a banana in the tailpipe by any measure, but operating range remains the most important EV performance metric. To this end Cycle World Road Test Editor Michael Gilbert methodically tested battery consumption by repeatedly riding a 48-mile loop that includes a blend of 18 freeway miles, stop-andgo city streets, a stretch of the Pacific Coast Highway, and a canyon road. Ridden in similar fashion, each bike completed a lap in Sport, Street, and Eco ride mode settings with the battery fully charged at the start of each lap. The average one-lap consumption for the LiveWire was 48 percent of its battery capacity, versus 57 percent aboard the SR/F Premium. Viewed another way, the Harley consumed 7.440 kWh while the Zero used 8.208 kWh per lap.
Limiting these electron burners to city life is a disservice to their sporting potential.
Another consideration is charging options provided by each bike. Both offer Level 1 charging that simply involves plugging the included charge cable into a standard 120-volt household outlet. We found the Zero takes under nine hours to fully charge from empty on Level 1, while the Harley’s larger RESS requires upward of 12 hours. Things get more complicated when using fast-charge capability. Zero employs Level 2 charging, while Harley has opted for faster Level 3 DC Fast Charging technology. Level 2 is currently more widely supported at commercial EV charge stations, and while you can hook the LiveWire up to a Level 2 charger, it will only replenish the battery at the Level 1 rate.
With its 6 kW integrated charger connected at Level 2, our SR/F Premium required 1.5 hours to achieve a 75 percent charge. Expect upward of an additional hour to reach 100 percent SOC because the Zero’s rate of charge slows when nearing a full charge state to prolong battery service life. While the LiveWire wowed us with a Level 3 recharge from zero to 100 percent in 58 minutes, it comes with a caveat: Harley recommends a 4:1 ratio of four Level 1 charges to every Level 3 fast charge to reduce stress on the RESS.
Limiting these electron burners to city life is a disservice to their sporting potential, as each comes equipped with fully adjustable Showa suspension, dual four-piston radial-mount calipers up front, and sticky sport radial rubber. A plan was hatched to conduct the final test phase while carving some Central California back roads.
I met up with Gilbert and our photography/video team in the Central Valley town of Taft for two days of backroad bliss. For reasons of practicality, the bikes arrived in the Cycle World Nissan van with a full charge. Having ridden the LiveWire at the bike’s Portland, Oregon, international press launch, I was getting my first glimpse of a Zero SR/F in the flesh.
2020
HARLEY-DAVIDSON
LIVEWIRE
MOTOR
Type
REVELATION INTERNAL PERMANENT-MAGNETIC SYNCHRONOUS W/ WATER-JACKET COOLING
Battery
15.5 KWH RECHARGEABLE ENERGY STORAGE SYSTEM (RESS)
Charging Compatibility
LEVEL 1/DC FAST CHARGING
Final Drive
1-SPEED/BELT
CHASSIS
Suspension
SHOWA 43MM SEPARATE FUNCTION FORK - BIG PISTON (SFF-BP), FULLY ADJUSTABLE; 4.5-IN. TRAVEL
Suspension
SHOWA BALANCE FREE REAR CUSHION-LITE (BFRC-LITE), FULLY ADJUSTABLE; 4.5-IN. TRAVEL
Front Tire
MICHELIN SCORCHER 120/70-17
Rear Tire
MICHELIN SCORCHER 180/55-17
Rake / Trail
24.574.3 IN.
Wheelbase
58.7 IN.
Seat Height
31.3 IN.
Dry Weight
544 LB.
CW MEASURED PERFORMANCE
Horsepower
92.8 HP @ 9,900 RPM
Torque
74.2 LB.-FT. @ 5,900 RPM
Quarter-Mile
11.54 SEC. @ 110.6 MPH
0-30
1.47 SEC.
0-60
3.12 SEC.
0-100
7.35 SEC.
Top-Gear Roll on 40-60
1.17 SEC.
Top-Gear Roll on 60-80
1.71 SEC.
Braking 30-0
33.45 FT.
Braking 60-0
133.27 FT.
Price
$29,799 $30,149 (AS TESTED)
HORSEPOWER
HARLEY-DAVIDSON LIVEWIRE MaxPower: 92.8 hp@9,900 rpm • MaxTorque: 74.2 lb. -ft. @ 5,900 rpm
2020
ZERO MOTORCYCLES
SR/F PREMUIM
ZF75-10 AIR-COOLED AC MOTOR
14.4 KWH LITHIUM-ION BATTERY
LEVEL 1/LEVEL 2
1-SPEED/BELT
SHOWA 43MM SEPARATE FUNCTION FORK - BIG PISTON (SFF-BP), FULLY ADJUSTABLE; 4.7-IN. TRAVEL
SHOWA MONOSHOCK,
FULLY ADJUSTABLE; 5.5-IN. TRAVEL
PIRELLI DIABLO ROSSO III 120/70-17
PIRELLI DIABLO ROSSO III 180/55-17
24.573.7 IN.
57.1 IN.
31.3 IN.
502 LB.
100.2 HP @ 4,500 RPM
146.5 LB.-FT. @ 1,200 RPM
11.83 SEC. @ 116.2 MPH
1.72 SEC.
3.65 SEC.
7.70 SEC.
1.23 SEC.
1.73 SEC.
33.61 FT.
131.91 FT.
$19,495
$21,495 PREMIUM MODEL (AS TESTED)
ZERO MOTORCYCLES SR/F PREMIUM MaxPower: 100 hp@4,500 rpm • MaxTorque: 146.5 lb.-ft. @ 1,200 rpm
Tip the Harley in, and it holds your chosen cornering line with steadfast conviction.
A brief walk-around of the California-built Zero didn’t provoke love at first sight. The paint finish on our Zero had an uneven overspray texture, and unsightly staples visible in an inch gap between the leading edge of the saddle and faux tank gave an unfinished appearance. Even the mirrors are flimsy compared to those of the more polished and refined LiveWire. The Zero’s handlebar switch gear appears to be a Chinese knockoff of Aprilia Shiver parts, while the LiveWire makes use of riderinterface components found on premium Harley touring models, utilizing dual thumb-operated joysticks for dash menu selection, phone, and music management, as well as turn-by-turn navigation. The clincher came when I saddled up for my first ride on the Zero and gripped its bars to discover sloppy free play in the left grip, something akin to the slack felt in a throttle twistgrip. Why?
The majority of the first of two ride days was spent doing photo passes among an army of grasshopper oil pumps that dominate the Taft landscape. Artistic irony pitting ebikes against a crude backdrop, explained veteran staff photographer Jeff Allen. Whatever the case, riding back and forth while trying to remain in focus just doesn’t get any easier than doing so aboard a twist-’n’-go EV with no clutch or gearshift to manage.
The best fun came at the end of the day, riding a stretch of tight curves in the hills west of McKittrick. Just as Gilbert and I had begun to explore the handling performance and swapped bikes for comparative impressions, the sun set in concert with both bikes’ diminished state of charge as we rode them to empty intentionally. Van loaded, we relocated to an Airbnb in Bakersfield for a night’s rest and recharge. Finding the garage of the residence bursting at the seams with the property owner’s stuff, we rolled the bikes into the living room for an outlet and awoke 10 hours later to a fully charged Zero and 72 percent state of charge on the Harley.
Utilizing the ChargePoint app installed on his mobile phone, Gilbert pinpointed the nearest Level 3 charging station. Fortune smiled as the hookup located in a parking stall of a Cafe Rio Mexican Grill was adjacent to Bagels & Blenderz, allowing us to graze during the bike’s 28-minute top-up. Washing down a gourmet breakfast burrito with a high-octane double-shot latte sparked a dim thought in my noggin: For every penny saved at the pump, how much retail expenditure and calories consumed does an EV owner incur?
To preserve our charge for a stint of high-energy depletion in the Sierra foothills, we once again loaded the bikes in the van. Gilbert and I conducted back-to-back runs on each bike through a choice stretch of curves along State Route 155. Here, it became apparent the LiveWire tracks corners with more confidence and precision than the Zero. Tip the Harley in, and it holds your chosen cornering line with steadfast conviction, while a similar act aboard the Zero results in an uneasy wallow and wiggle when the road surface isn’t billiard-table smooth. Maintaining a relaxed grip on the bars and consciously avoiding leaning upper body weight onto the Zero’s wide one-piece bar helped minimize unwanted steering input. The LiveWire doesn’t require any such kid-glove treatment.
Gilbert found the Harley’s Sport-mode throttle response the most natural and better connected at the right wrist while also favoring its more pronounced off-throttle regeneration (engine-braking feel) for the lessened reliance on brake pressure to slow to a halt, important because the LiveWire’s classic wide-blade-shaped lever found on its V-twin cruisers feels out of place on this sporty platform, and it robs brake feel when you need it most. I preferred the lighter regen of the Zero’s Sport mode, finding it a bit reminiscent of a two-stroke coasting on corner entry. I also found the Zero’s two-stage regen interesting, in that it increases regen effect when the front brake is applied, delivering a clever form of linked braking. The good news is both bikes offer the ability to adjust certain parameters to your liking and save them to a custom ride mode.
The LiveWire’s customizable settings include power, throttle response, and regen settings from zero to 100 percent, along with three levels of traction control, plus TC off. The Zero’s custom ride modes offer more adjustabilityincluding max speed, power, max torque, closed-throttle regen, and brake regen, as well as three TC settings (Street, Sport, Rain) plus off—but is only accessible through the mobile app, and only allows one custom mode to be loaded at a time. The Harley has three custom presets easily accessible on the dash that can be selected while riding.
I was aboard the Zero late in the day, enjoying the flow with light-handed finesse through the remaining good twisty bits, when a sudden loss of power ensued. The Zero goes into limp-home mode for the last 10 percent of charge, with maximum power and peak speed tailing off ever so steadily with each remaining mile. Imagine your liter-class four dropping a cylinder, and then another, until it’s running on one lung over the final mile before coasting to an anticlimactic halt.
The Zero was dead at 67 spirited miles, while the Harley had 12 miles of range remaining and also delivered full performance to the last watt. Again, it was our intent to test comparative range, and we intentionally rode them to the end, but if not for the chase van, I can only imagine being stranded roadside with the charge cord in an outstretched hand hoping to flag down a passing motorhome. Owners will certainly learn to plan their rides.
At $21,495 (as tested), reduced sticker shock favors the Zero SR/F Premium. But that isn’t grounds to avoid an honorable discharge and second-in-class ranking. Superior acceleration, sure-footed handling, more range (combined with a quicker charging option), and a more complete and intuitive TFT suite with music and navigation all wrapped in exquisite fit and finish befitting a bike costing $30,149 (as tested) add up to the Harley-Davidson LiveWire being a four-star general of electrics.
