Cycle News

VOL. 52 ISSUE 7 FEBRUARY 18, 2015 P55 the electric motor's strong but controllable pickup from rest, and then you enjoy its diagonal power curve and horizontal torque delivery. Acceleration is truly impressive, yet delivered so smoothly and immediately to the seductive, speedy sound of silence. I tell you, there's nothing on the road with an exhaust pipe that'll beat a Zero SR away from the lights. Yet in urban conditions the SR is just as easy and control- lable to ride as any less potent E-package, especially since you don't have to worry about working the clutch lever to coax the motor into delivering drive. There's still nothing to match an E-bike with such responsive YOU inches, which are both fully adjustable for preload plus rebound and compression damping. So why the high-end sus- pension? "Since the begin- ning we've wanted to posi- tion ourselves as a premium brand," says Askenazi. "A Zero is not a toy, it's a real motorcycle and a very good one. If you're riding a bike every day as, say, a com- muter, you should be able to adjust the motorcycle's suspension to suit your riding style, your weight, your mood and so on. We went for high-end suspen- sion both from the stand- point that we're a premium motorcycle company, and also from a comfort aspect relative to the usability of these motorcycles." In keeping with the same philosophy is the fitting for 2015 of Pirelli tires, again on all models, with high-end Diablo Rosso II rubber on the SR, Sport Demon on the S, MT-60 dual purpose cov- ers on the DS and Scorpion MT-90s on the FX. Likewise the adoption across the board of Bosch Gen 9 ABS, the first time this has ever been installed on an electric motorcycle equipped with regenerative braking, as all Zero models are. "We embarked on this ABS development with Bosch, which has entailed a lot of resources and ex- pense, because we thought it was critical for the com- pany to do this as a premium high technology brand," explains Askenazi. Zero also collaborated with J-Juan in Spain to supply the adjustable front brake lever (the rear brake is operated by your right foot, not by a second handlebar lever as on some E-bikes), master cylinders, braided metal brake hoses, and the twin piston front caliper and single-piston rear, and also upgraded the brake disc sizes to a 320mm front and 240mm rear. Note that the front disc is bolted directly to the spokes of the Zero- designed wheels made in China by ZDM, a light and airy design by Matt Bentley which Askenazi says allows the new bolted-on front brake to outperform the previous carrier design, since it stays cooler as its heat sinks into the wheel casting. And instead of the nowadays conventional sensor rings on an ABS wheel, Zero has incor- porated the wheel speed sensor actually into the hub via a magnetic ring for a cleaner look and more robust design. Harley-Da- vidson already has a similar system with the magnetic ring incorporated into the bearings, but the Zero ABS is even more discreet in appearance. Zero produces its own lithium-ion pouch cell battery packs, which come in two different 102-volt power configurations, which the customer chooses at the point of sale, and the differ- ence in range is what sets them apart. Each is claimed to be good for 2,500 recharge cycles from zero, which gives a claimed ef- fective battery pack lifetime of 415,000 city miles for the bigger version—meaning they'll outlive the motorcycle they're installed in, so the substantial cost of replace- ment isn't an issue. The more expensive 12.5 kWh option contains four battery modules, aka cell boxes, each with 28 pouches. and built in-house at Zero using Farasis cells. The less costly 9.4 kWh version has three modules, thus delivers reduced range. So it's not surprising that 85 percent of Zero owners apparently go for the bigger powerpack when purchasing their bike. Using the on-board 1.3kW charger fitted to all Zero models – the char- ger socket is on the left frame spar upright above the swingarm pivot, the batteries can be recharged using a household socket from empty to 95% charge in 10hrs on the four-module pack, while using Zero's $599 quick charger acces- sory can bring a full charge down to six hours. With multiple quick chargers you can bring the wait down to 2.3 hours, but by using a CHAdeMO accessory DC fast charger hookup—as used on the BMW i3, Nis- san Leaf and so on, giving access to the network of charging stations rapidly spreading worldwide—this can be reduced to exactly an hour for a 95 percent charge on the bigger 12.5 kWh battery pack, and just over an hour if the 2.8 kWh Z-Force Power Tank is attached. That's because it charges straight into the battery, and the limiting fac- tor in terms of speed is only the charge rate capacity of the individual cells, but the problem is there's no space on a Zero to carry the large $1799 charge lead and connector around to find a charger.

• Cover