Riding the tailwinds of waxing public interest and expanding infrastructure, Zero Motorcycles advanced 'The Cause' with new improvements and adjustments to its street-centric “S” and “SR” models last year. Part of that was the addition of a more powerful motor that generates increased torque and horsepower as well as a smaller battery pack for short urban trips; all good stuff for increased fun and flexibility, necessary factors if the company wants to further its push into the mainstream. For 2018, Zero adds more range and quicker charging times.

Continue reading for my review of the Zero S and SR.

2017 - 2018 Zero Motorcycles S / SR

Specifications
  • Make: Array
  • Model: 2017 - 2018 Zero Motorcycles S / SR
  • Engine/Motor: Z-Force
  • [do not use] Vehicle Model: Array

Zero Motorcycles S/SR Design

While these changes will likely benefit Zero, I submit that at this stage in the game, anything that increases the appeal and feasibility of electric transportation is good for electric vehicles in general with a direct, positive impact on the environment. As the streetfighter class for the company, these two rides necessarily come in the typical “standardsportbike format with jockey footpegs and very little rise or pullback in the handlebars. A forward-leaning rider position is encouraged but not forced, a balance that reaches a compromise between aggression and comfort.

A small headlight can and lack of full front fairing nudges these two into the “naked” sub-category. While the rest of the bike does carry more paneling than a smoker naked bike might, the concealment it provides for the innards helps keep these bikes looking relatively typical and prevents them from sticking out like a proverbial sore thumb around smokers.

The exposed wishbone of the twin-spar frame is exposed on the sides, but the black paint makes it sort of blend into the background so it doesn't really contribute much to the overall look. Small cheek fairings extend forward from the un-gas tank, but the factory took steps to keep the flylines looking right with a fairly standard shape even though it was completely unnecessary to do so.

A shallow-scoop seat rises to the p-pad on the subframe, and the ass end quickly tapers down to a point with a sporty spray guard that mounts the license plate. Since the taillight comes tucked up under the subframe and the turn-signal standoffs are kept to a minimal length, both front and rear come off looking nice and clean.

Zero Motorcycles S/SR Chassis

Aircraft-grade aluminum makes up the twin-spar frame that weighs in at an incredibly low 23 pounds, a major contributor to keeping the overall weight well below the 500-pound mark. The frame layout pulls the seat down to 31.8-inches tall, and pushes the wheelbase out to 55.5-inches long with a short, 24-degree rake and 3.2-inch trail that gives the bike canyon-carving agility even though stability at speed suffers a bit. Oh well, you can't have it both ways after all.

Fully adjustable suspension provides the comfort and flexibility riders are coming to expect nowadays. Inverted 41 mm forks support the front end with a 40 mm, piggyback monoshock in back. Components at both ends come from Showa -- a trusted name in mid-shelf suspension -- and they provide all-around adjustment to compression and rebound damping as well as spring preload. While it's possible to get fancier with the suspension, it ain't going to happen at these prices.

Wheel travel at the axle falls at 6.25- inches up front and 6.35-inches in back, which is pretty plush, and you can prevent it from feeling too soft in the corners with the adjustments so it's a win-win no matter how you look at it. Twin-piston J-Juan calipers bite the dual, 320 mm front discs, and a single-pot caliper pinches the 240 mm disc in back with Bosch's Gen-9 ABS on overwatch. Pirelli's Diablo Rosso II hoops line the cast, 17-inch rims, and the sticky tires come in 110/70 and 140/70 profiles.

Front suspension:

Showa 41 mm inverted cartridge forks, with adjustable spring preload, compression and rebound damping

Rear suspension:

Showa 40 mm piston, piggy-back reservoir shock with adjustable spring preload, compression and rebound damping

Front suspension travel:

6.25 in (159 mm)

Rear suspension travel:

6.35 in (161 mm)

Front brakes:

Bosch Gen 9 ABS, J-Juan asymmetric dual piston floating caliper, 320 x 5 mm disc

Rear brakes:

Bosch Gen 9 ABS, J-Juan single piston floating caliper, 240 x 4.5 mm disc

Front tire:

Pirelli Diablo Rosso II 110/70-17

Rear tire:

Pirelli Diablo Rosso II 140/70-17

Front wheel:

3.00 x 17

Rear wheel:

3.50 x 17


Zero Motorcycles S/SR Drivetrain

The biggest improvement from last year lies in the drivetrain components. First off, the factory bumped up power output across the board with a maximum of 60 horsepower out of the “S” and 70 from the “SR.” Torque received a bump as well with a maximum of 81 pound-feet and 116 pound-feet, respectively. As always, that torque is available the instant you crack the electronic “throttle” without the need to first gather the rotational inertia in the engine. If you can't imagine what that means, I assure you all ambiguities will be removed the instant you throw a leg over and grab a fistful.

Unlike some of the competitors out there, Zero runs a direct drive that precludes the need for a clutch or shifter, thus simplifying the skillset needed to handle the machine. Similar to high-performance smoker bikes, these rides sport a rider-mode function that allows you to choose between maximum power delivery and more conservative power curves for extended ranges.

Range and charging times are the main considerations when deciding whether EVs are right for you, and one can expect to get around 100 miles at highway speeds and 200 miles in the city stop-and-go. While the highway performance will require significant infrastructure to be practical on a road trip, I gotta' say that 200 miles in the city is plenty for most urban commutes, and at current electricity prices, you're paying a mere penny per mile to do it. That's right folks, I said $0.01 per mile, so if you ride as much as I do, the gas savings will pay for the bike in a reasonable, if variable, amount of time.

Capacity depends on the battery options you pick from the 2017 options -- 6.5 kW, 13.0 kW or 16.3 kW -- as do the charge times along with the added complication of the mix-and-match charging system, so you can literally tailor your system to your specific needs, and since it's all modular you retain the option of making adjustments later if necessary. Top speeds are limited to around 102 mph depending on state of charge, motor temperature, tailwinds and how much you had for lunch, but as always I'll point out that on public roads you can't even safely/legally go that fast, so the bottom line is that's plenty mo' fast enough.

For 2018, the factory boosted the power density of its batteries along with a rather amazing leap in its charging technology. The new lithium-ion storage units come in the ZF3.6, ZF7.2 and ZF14.4 kWh sizes with an optional ZF3.6 Power Tank that boosts the capacity/range further yet when coupled with the 14.4 main battery for a total of 18 kilo-Watt hours and a “city range” of 223 miles, depending on terrain and riding style of course. You heard right folks, this makes the Zero even more viable as a commuter, but the factory didn't stop there, it doubled down with a faster charger, much faster.

If recharging times are more important to you than miles-per-charge figures, then the 6 Kw Charge Tank feature may be for you with its ability to quickly slam a charge into the pack via 110/220 V AC household receptacle or a Level 2 charging station. Additionally, the factory re-wrote its mobile App Firmware so you can use your mobile device to tweak the performance delivery rather than hauling it down to the dealership. What's this all mean? Well, in short, it gives EV bikes a violent shove into the viable zone. Anything that advances EV tech is good for the industry as a whole since it's still fighting for mainstream acceptance, but this enhancement ensures that Zero will remain ahead of the curve for the time being.

Zero’s new 6 kW Charge Tank allows riders to charge at speeds of up to 103 miles per hour of charging at any of the growing number of over 14,000 Level 2 charging stations in the US or around the world,” says Zero's CTO Abe Askenazi. “This means riders can add 30 miles of ‘fuel’ in the time it takes to stop for a cup of coffee or fully recharge over lunch. This completely changes the utility of electric motorcycles by eliminating long recharging times.”

Motor:

Z-Force® 75-5 passively air-cooled, high efficiency, radial flux, interior permanent magnet, brushless motor

Input:

Standard 110 V or 220 V

Transmission:

Clutchless direct drive

Final drive:

90T / 20T, Poly Chain® HTD® Carbon™ belt


Zero Motorcycles S/SR Price

The “S” base price with the 7.2 kW battery goes for $10,995, but the 13.0 kW battery bumps that on up to $13,995. The optional power tank that extends riding range tacks another $3k onto that, or you can go instead with the charge tank that slams a fresh charge into the batteries post haste for another $2k. Understandably, the “SR” is a bit prouder at $16,495 with the 14.4 pack. While these prices are comparable to smokers, I would be remiss if I didn't point out that there are no oil changes, no spark plug swaps, no clutch to wear out and it beats the pavement to the tune of a mere penny-per-mile. In other words, it's dead cheap to operate, and prospective buyers should bear that in mind.

Price:

$10,995 to $16,495

Standard motorcycle warranty:

2 years

Power pack warranty:

5 years/unlimited miles


Zero Motorcycles S/SR Competitors

Since Victory's Empulse TT performed so well on the Isle of Mann not long ago, single-handedly propelling electrics into the realm of performance racebikes, I thought it fitting to use it here for a short head-to-head.

Right off the bat one can't help but notice the look of the Empulse isn't quite as polished as the Zero rides, and fairly screams “look at me, I'm something different,” especially in the presence of typical smoker bikes. It's fine if you are into looking conspicuous, but to mine eyes the “S” takes it just far enough and no further.

Aesthetics are subjective, but what isn't are the power numbers. The 46 ponies and 78 pound of grunt from the base “S” falls a little short of the 54 horsepower and 61 pounds from the Empulse. Thing is, at $19,999 you're going to pay a Hell of a lot for that difference over the base Zero, and for a few grand more than the starting sticker, Zero pumps that on up to 60 horsepower and 81 pounds of torque and still manages to stay well below the Empulse on price. Not sure why Victory has to be so mean at the till, but there it is. Sorry guys, EV is cool, but I can think of literally dozens of bikes I'd look at before I spent 20 grand on a battery-powered ride. Plus its kind of ugly compared to the sexy curves of the Zero. Just sayin'.

Victory has since gone tits up, but Polaris owns the Brammo-based Empulse now, and scuttlebutt has it that Polaris has no intention of letting that tech go to waste, so you should expect to see something very Empulse-like from them or their Indian Motorcycle holdings in the foreseeable future. If they're smart, theyll bring the price down (way down) and get it on showroom floors before Harley-Davidson unleashes its LiveWire next year.

He Said

“Love it, love it, love it! Of all the electrics I'd say this is my current favorite, and even though we do have some newcomers in 2017 that I haven't looked at yet, the Zero products are the measuring stick by which I gauge the rest of the field. Yeah OK, Energica has some very sharp-looking rides that look more natural to a smoker-bike rider, but they come off looking like they're trying a little too hard if you know what I mean. EV ain't perfect yet, but I feel like Zero is on the right track, for sure.”

She Said

My wife and fellow motorcycle writer, Allyn Hinton, says, "I really like this upstroke of electric motorcycles, but I wonder if the technology developing now that turns CO2 in the atmosphere into ethanol will dampen it at all. Since ethanol can be burned as a fuel with very little modification to existing internal combustion engines, I wonder how that's going to impact the push toward alternate energy and electric vehicles in general. Oh well, time will tell. In the mean time, these Zero's are the bomb-diggity, but I'm still cautious about the lack of sound. I like to be heard when I'm on two wheels for safety's sake. The extended ranges on the "S" make it so much more viable as a commuter and an all-around fun ride."

Zero Motorcycles S/SR Specifications

Zero Motorcycles "S" Specifications

Battery

ZF7.2

ZF13.0

ZF13.0 +POWER TANK

City:

89 miles (143 km)

161 miles (259 km)

206 miles (332 km)

Highway, 70 mph (113 km/h):

45 miles (72 km)

81 miles (130 km)

103 miles (166 km)

Combined:

60 miles (97 km)

108 miles (174 km)

138 miles (222 km)

Peak torque:

78 ft-lb (106 Nm)

81 ft-lb (110 Nm)

81 ft-lb (110 Nm)

Peak power:

34 hp (25 kW) @ 4,300 rpm

60 hp (45 kW) @ 5,300 rpm

60 hp (45 kW) @ 5,300 rpm

Top speed (max):

91 mph (146 km/h)

98 mph (158 km/h)

98 mph (158 km/h)

Max capacity:

7.2 kWh

13.0 kWh

16.6 kWh

Typical cost to recharge:

$0.81

$1.46

$1.86

Charge time (standard):

5.2 hours (100% charged) / 4.7 hours (95% charged)

8.9 hours (100% charged) / 8.4 hours (95% charged)

11.3 hours (100% charged) / 10.8 hours (95% charged)

With Charge Tank option”

1.5 hours (100% charged) / 1.0 hour (95% charged)

2.3 hours (100% charged) / 1.8 hours (95% charged)

N/A

With max accessory chargers:

1.6 hours (100% charged) / 1.1 hours (95% charged)

2.6 hours (100% charged) / 2.1 hours (95% charged)

3.1 hours (100% charged) / 2.6 hours (95% charged)

Curb weight

:313 lb (142 kg)

408 lb (185 kg)

452 lb (205 kg)

Carrying capacity:

329 lb (149 kg)

367 lb (166 kg)

323 lb (147 kg)


Zero Motorcycles "SR" Specifications

Battery

ZF14.4

ZF14.4 +POWER TANK

City:

179 miles (288 km)

223 miles (359 km)

Highway, 70 mph (113 km/h):

90 miles (145 km)

112 miles (180 km)

Combined:

120 miles (193 km)

150 miles (241 km)

Peak torque:

116 ft-lb (157 Nm)

116 ft-lb (157 Nm)

Peak power:

70 hp (52 kW) @ 3,500 rpm

70 hp (52 kW) @ 3,500 rpm

Top speed (max):

102 mph (164 km/h)

102 mph (164 km/h)

Max capacity:

14.4 kWh

18.0 kWh

Typical cost to recharge:

$1.61

$2.02

Charge time (standard):

9.8 hours (100% charged) / 9.3 hours (95% charged)

12.1 hours (100% charged) / 11.6 hours (95% charged)

With Charge Tank option:

2.5 hours (100% charged) / 2.0 hours (95% charged)

N/A

With max accessory chargers:

2.8 hours (100% charged) / 2.3 hours (95% charged)

3.3 hours (100% charged) / 2.8 hours (95% charged)

Curb weight

:414 lb (188 kg)

458 lb (208 kg)


Zero Motorcycles S/SR Motorcycle Specifications

Motor:

Motor:

Z-Force® 75-5 passively air-cooled, high efficiency, radial flux, interior permanent magnet, brushless motor

Input:

Standard 110 V or 220 V

Motor:

Transmission:

Clutchless direct drive

Final drive:

90T / 20T, Poly Chain® HTD® Carbon™ belt

Drivetrain:

Front suspension:

Showa 41 mm inverted cartridge forks, with adjustable spring preload, compression and rebound damping

Rear suspension:

Showa 40 mm piston, piggy-back reservoir shock with adjustable spring preload, compression and rebound damping

Front suspension travel:

6.25 in (159 mm)

Rear suspension travel:

6.35 in (161 mm)

Front brakes:

Bosch Gen 9 ABS, J-Juan asymmetric dual piston floating caliper, 320 x 5 mm disc

Rear brakes:

Bosch Gen 9 ABS, J-Juan single piston floating caliper, 240 x 4.5 mm disc

Front tire:

Pirelli Diablo Rosso II 110/70-17

Rear tire:

Pirelli Diablo Rosso II 140/70-17

Front wheel:

3.00 x 17

Rear wheel:

3.50 x 17

Chassis :

Wheelbase:

55.5 in (1,410 mm)

Seat height:

31.8 in (807 mm)

Rake:

24.0°

Trail:

3.2 in (80 mm)

Dimensions:

Frame:

23 lb (10.4 kg)

Weight:

MSRP:

$10,995 to $16,690

Pricing:

Standard motorcycle warranty:

2 years

Power pack warranty:

5 years/unlimited miles


References

Victory Empulse TT

See our review of the Victory Empulse TT.