Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/1166337
2019 ZERO SR/F F I R ST R I D E R E V I E W P90 with the kind of muscular acceleration I was already well familiar with after riding each successive year's new Zero model since 2012—and then some. This is a huge step up from even last year's SR, let alone the Zero DSR I made a six-day 920-mile tour of Northern California on in 2016. Sure, the more powerful new motor plays a vital role here, but it's that seamless yet controlled delivery of the massive torque available as soon as you open the throttle, that's so invigorating. Sorry, Ducati—but this is a Monster 1200 on steroids, that's much easier to ride for the simple reason that you're always in the right gear, and don't have to work your left hand or foot at any time. Moreover, Zero has made the SR/F super controllable via the choice of distinct riding modes now on offer, even if I didn't, fortunately, have to worry about rain, and wasn't concerned about getting home, so didn't use eco. Returning to base after 85 miles of hard, hard riding saw 12 percent of charge still in the "tank" after a brief 30-minute top-up when we stopped for lunch. T he SR/F's ZF75-10 brushless Z-Force AC motor created in-house represents a significant upgrade to the previous design. This is a radial flux sealed motor, whereby the permanent interior magnets are located on the single moving part, i.e., the rotor, while the com- ponents which get hottest—the windings, aka coils—are mounted on its periphery, whence the heat can be dissipated via a deeply finned circular aluminum housing. This means there's no bulky, heavy liquid cooling, since the motor is passively air-cooled, hence there's no fan, although the Bentley boys' refined styling does feature a chin fairing that fun- nels air beneath the battery box to the motor positioned in the swingarm pivot, and the controller mounted in front of it, to provide additional cooling. The SR/F's version of the mo- tor is 30mm wider than before, which of itself produces more power—110bhp/82kW at 5000 rpm, and a constant 140 lb-ft of torque from 1 rpm onwards. That's quite some increase from the 70bhp/52kW and 116 lb-ft delivered by the previ- ous SR's ZF75-7R motor, so the SR/F is the first Zero model to produce more than 100 bhp. Top speed has also risen commensurately to a claimed 124 mph (from 102 mph on the SR) thanks not just to the extra power from the motor, but also a 1000 rpm increase in peak revs to 7500 rpm. The SR/F was modeled on the need for a Euro-style naked bike. The styling clearly worked. POWERUNIT