2015 Zero Electric Motorcycles | FIRST RIDE

Call it the tipping-point syndrome. Zero Motorcycles has been in business roughly since 2006. We say "roughly" because that product was essentially an electrified mountain bike. But the company has been producing, albeit in small quantities, since 2009 an eBike lineup that has continued to edge toward motorcycle-like manners and respectability.

It’s only in the last couple of years, though, that Zero has dramatically advanced the state of the art in electric motorcycles. Consider that in 2011, the Zero S had a little more than 4 kWh of battery capacity and city range of just 40 miles. (Program note: Every reference to battery capacity here is maximum capacity. Then you have nominal capacity, which Zero describes as "the most accurate measure of the amount of usable energy that can be stored in a vehicle’s power pack. It differs from maximum capacity because it is calculated using an average voltage that is more often ‘the norm’ rather than a maximum which is rarely seen." Nominal capacity is approximately 88 percent of maximum capacity.)

In 2012, those figures were 9.0 kWh and 110 miles. The following model year, 2013, saw larger battery packs still: up to 11.4 kWh for a city range of nearly 140 miles. Last year saw another bump, to 14.2 kWh with a city range of 150 miles.

Now for 2015, those trends carried through so that the Zero S (and its similar SR) have a maximum battery capacity of 15.3 kWh and a corresponding city range of more than 180 miles.

Two important considerations regarding range estimates before we go much further. City range is the best-case scenario, where the bike is run at relatively low speed and is allowed to use the regeneration feature to put some energy back into the batteries on “engine braking.”

Staying on the Zero S model, where city range is a claimed 185 miles with the maximum number of battery cells installed, you get an estimated range of 141 miles when you run a 50/50 mix of city and highway at or below 55 mph. If you speed up during the highway segment to 70 mph steady state, the new combined range is estimated at 125 miles. Worse case? Highway travel, and the faster the worst(er). Run 55 mph and you’ll be done after 115 miles; zip along at 70 and you’ll go 94 miles.

What’s this about capacity? Two model years ago, Zero made an important decision to simplify its product lineup and codify two basic battery modules, one for the FX (and its military MMX model) and one for everything else. Made up of 28 “cells” wired in series, these 42-pound “bricks” produce 102 volts and 3.13 kWh of capacity each—except for the FX/XMX brick, which remains a 2.8 kWh brick. (To be accurate, the battery modules themselves weigh 37 pounds, with the rest made up of the contactor, current sensor, main fuse, and "battery management system" hardware.) All models but the FX get a water-sealed box where your internal-combustion engine should be that can carry three or four bricks; giving a basic capacity of 9.4 or 12.5 kWh. Leaving out one of the bricks saves 32 pounds and about $2,000 off the MSRP, while cutting range by about a quarter.

There are still more capacity options. Last year, Zero introduced the Power Tank, which is the same smaller, 2.8 kWh module used in the FX mounted where the “trunk” normally is. All of the ranges quoted above are for a Zero S with all four centrally mounted bricks and the Power Tank.

Confused? Well, yes; Zero has made a number of configurations available, and there’s something to be said for saving the weight and cost of the fourth battery or the Power Tank if you don’t absolutely need the range. Also, you can have a bike with the three-brick battery setup and add a Power Tank later if you want.

One last word on the Zeros’ power supply and we’ll move on. Previously, the battery chemistry was optimized for one application in the Zero line, the military MMX, which slightly favored energy transfer over capacity. (It’s a complicated deal, but basically a battery that can give a large amount of its energy quickly tends to have less overall capacity, all else being equal.) For 2015, Zero has decided to use a one battery chemistry for the FX and MMX and another for the rest of the line, which allows it to optimize the ratio of power transfer and capacity. As a result, the Zero S, SR, and DS have gained 10 percent capacity, which translates into increased range.

These are all important steps on the way to a better eBike, but something else has happened: Zero has gained respect in the manufacturing realm. That’s why Showa has elected to work with Zero, and why Bosch is on board to supply its latest ABS module, and why Spanish brake maker J. Juan is supplying calipers and master cylinders across the line. What’s happened is that Zero is now considered big enough and important enough for these companies to work with them the same way they would with acknowledged motorcycle manufacturers. As such, Showa came to Zero’s Scotts Valley, CA, headquarters with a full set of test equipment and technicians to refine the components used across the line. J. Juan worked with Zero on an engineering level to develop specific parts for the line, and once that was done, Bosch developed specific software for the Generation-9 ABS. It’s no longer the case that Zero has to buy “off the shelf” items. And this year’s Zeros are $350 more expensive, ABS is standard across the line. Last year not even available, this year everyone gets it.

Over a day and a half of riding, we got to sample all four of Zero’s current models. Remember that the Zero S, SR, and DS share a frame, newly redesigned saddle, basic bodywork, battery configurations, and motor; the exception is that the SR has a high-output motor and higher-capacity controller. Here’s the rundown.

This is Zero’s hot rod. Thanks to a set of permanent magnets capable of handling higher temperatures before de-magnetizing, the SR boots down 67 hp and 106 pound-feet of torque—compared to 54 hp and 68 pound-feet of torque for the S and DS models. Even when loaded down with a full four-brick battery pack and the optional Power Tank, the SR feels quick. After a typically soft initial throttle takeup, the SR’s controller begins to exhort the tiny motor to get to work. Low-end and midrange acceleration is brisk, easily on pace with a small internal-combustion motorcycle, all without the need to deal with a clutch or even shift. Yes, after a few hours in the saddle, I stopped reaching for a clutch lever at stops and once again got used to the bike making absolutely no noise at a stop.

Handling, thanks to the new Showa suspension, is dramatically improved. Up to now a Zero sore spot, ride quality is very good, though the spring rates are on the soft side for really aggressive riding. (It’s actually saying something that this comes up at all.) Both the Zero SR and the slightly lower powered S feel a bit unusual in that they’re short-wheelbase (55.5 inches, which is just 1.2 inches more than a Honda CBR300R’s) machines with a big chunk of weight in the midsection. The ride motions are more like a heavier bike, while the steering is quick and responsive.

Our ride on the SR included a serious bash through the hills near the company’s HQ, where the goodness of the new suspension, brakes, and tires was massively evident. The suspension handles most bumps with ease, though a few of the bigger ones get through with minimal filtering; still, the ride is a massive improvement over the previous Fastace setup.

At the beginning of the ride, the on-board range estimator said 86 miles, and 68 miles later showed a remaining range of 17 miles; close enough. Very little of this bash included the typical urban landscape, so the backroad flogging and little bit of highway droning did a number on range. The only issue that arose is one well known to Zero. Even with the greater heat capacity of the -7R motor, the system went into damage-prevention mode during a long uphill part of the twisty section. When the temp light starts flashing, you know that the motor is getting close to its temperature limits; when the light goes on steady, the system limits current (and therefore torque) to keep it under control. But, to be fair, we were pretty well hammering on the thing.

Available only with the full four battery bricks, the SR has a minimum battery capacity of 12.5 kWh, up to 15.3 kWh with the Power Tank. MSRP starts at $17,345, with the Power Tank a $2,495 option.

The company’s more mainstream model still performs well despite having less power. Sipping from battery capacities from 9.4 kWh to 15.3, the 54-hp motor provides better range than the hotter SR for any given battery configuration. Well, technically it doesn't. Efficiency is the same, so if you use only a certain amount of performance, the S and SR will have the same range. But let's be realistic here: If you have more power, more intoxicating torque, you're going to use it. Theory says the range will be the same. Reality? Something different. Either say, max range is a claimed 113 miles (city, smallest capacity) to 185 miles (city, all battery options ordered) with the high-speed “combined” figures ranging from 76 to 125 miles.

Besides packing a less powerful motor—an engineer might actually call this a less "thermally capable" motor—and having a controller capable of handling a bit less current, the S and the SR are basically identical machines. Oh, yes; the SR gets you an upgrade in standard Pirelli rubber, from Sport Demons to Diablo Rosso IIs. We rode an S without the Power Tank and you do notice the reduction in weight, which benefits acceleration, ride quality, and braking.

Prices start at $13,345 with the smallest battery pack (the ZF9.4), going to the four-brick pack (ZF12.5) adds $2,000, while fulling its little stomach with lithium-ion cells, via the Power Tank, adds another $2,495.

Perhaps our favorite of the new Zeros, the DS takes the SR/S package and bolts on longer-travel suspension—roughly three quarters of an inch at each end—along with larger cast wheels shod with Pirelli MT-60 dual-sport rubber. The handlebar is taller and wider, giving the cockpit a much roomier feel, though everything else under the skin follows Zero S format.

Somewhat amazingly, the DS feels quite different. Greater suspension travel provides a better ride, especially on rough roads, while the steering feels a bit more conventional. It is, actually, quite a lot of fun to ride. Still-quick steering makes you want to dodge slow-moving traffic and hop curbs in the city, and while the DS is really not aimed directly at the lighter ICE dual-sports, it would make a fine trail bike, assuming you don’t have to go far to hit the dirt.

The only oddity compared to a gas bike is that predicting wheelspin is difficult thanks to the soft off-the-bottom response and the rather sudden torque build up in the midrange. Roll open the throttle and the rear Pirelli stays hooked up for a long time and then, zzzzzzz, it’s spinning all at once. What’s more, you’ll have trouble lofting the front wheel to clear obstacles because of that soft throttle and lack of clutch, which would allow you to “snap it up” under the right circumstances. So, yes, a nice, sedate trail trekker not a quiet motocross bike.

Like the Zero S, the DS starts at $13,345, and can be had with the 9.4-kWh pack, the 12.5 pack (adding $2,000), and the Power Tank. It’s our thinking that the DS is just as adept at running you to and from work but has an added degree of capability over the S to make it attractive. The only downside is a slightly taller seat height and somewhat reduced range—on the order of 10 miles or so. Zero says the difference is almost entirely aerodynamic; the DS rider sits taller and creates more drag. Maybe he should tuck in.

The true outlier in the Zero lineup for 2015, the FX is a fun toy of an urban motorcycle. It feels considerably lighter than the S/DS models, and is; the lightest version of the DS weighs 381 pounds while the FX tips the scales to just 248. It’s tall, narrow, and flickable.

The FX is the only Zero to have less power based on the battery layout, which is either one or two 2.8 kWh packs. With one, you get 27 hp (and 70 pound-feet of torque), but double up and you get 44 hp with the same peak torque. We rode the two-battery version, which weighs 289 pounds, and got the overall impression of a satisfying quick bike from zero to 50 mph. As with the other models, the FX greatly benefits from relatively modern brakes and drastically better suspension. No more clanking down below, no more lunging over bumps.

As the most affordable Zero, the FX starts at $9,845 and goes up by $2,495 for the second battery pack. The high-speed “highway combined” range goes from paltry 21 miles on the single pack to 42 miles with both. (See, scaling works!) Just comfortable enough for short daily commutes or as a replacement for a small scooter—and by scooter we mean a crazy-torquey fun machine—the FX makes good sense as an entry-level eBike, assuming you can manage the 34.7-inch seat height.