ROTARY HYBRID SUPERBIKE – SPECIAL FEATURE

Meet the Re:gen e-SBK, a proposed hybrid rotary-electric superbike whose performance will put conventional 1000cc sportbikes in the shade, says its designer. All he needs now is the bucks to match the brains—including Norton and Formula One legends—contributing to the project.

Director of Re:gen, Rick Simpson, says the 397-pound, carbon-framed hybrid will offer the huge torque from zero revs of electric motors with the range and practicality of gas engines. That means you could enjoy the silent, emissions-free, in-town running of the saintliest ecomobile, with tire-melting superbike performance on tap when your mood turns devilish—and never have to worry about being caught with a flat battery miles from home.

Yamaha and Honda have also promised gas-electric hybrids in the near future. But neither is proposing a powertrain of the compactness and potency of the e-SBK, whose claimed figures match current liter-bikes for power while comfortably out-grunting even monsters like Yamaha’s 123 ft.-lb. VMax.

At the heart of the bike’s hybrid power unit will be a 350cc rotary engine built by Norton legend Brian Crighton, architect of the firm’s racing success in the 1990s and the new 170-hp NRV rotary racer. Crighton’s compact single-rotor engine will be paired with an electric motor derived from a 700-hp electric race car being produced by ex-F1 designer Martin Ogilvie. The complete package weighs just 55 pounds (less than half the weight of a comparable four-cylinder 1000cc engine) while putting out a claimed 160 hp and 150 ft.-lb. of torque. The central output shaft, common to both components, makes for a compact and easily packaged motor. And because the final drive is fully electric, no gearbox is needed. The e-SBK is a “series hybrid,” which means the rotary engine exists purely to supply power to charge the bike’s battery and ultracapacitor, rather than providing any drive directly to the back wheel. The battery efficiently supplies cruising-speed power, while the ultracapacitor deals with demands for rapid acceleration with massive, fast-discharged jolts of electricity.

It’s a much more efficient way of supplying a sportbike rider’s ever-changing demands for energy than a purely gas engine capable of producing 160 hp of peak power, with its inherently compromised low-end and midrange performance.

The e-SBK will also be able to carry far more energy in the form of gasoline than a purely electric bike can in the form of heavy batteries. That should make it lighter and cheaper, as well as offering greater range than all-electric rivals from Mission Motors and Roehr. Projections suggest a range of 120 miles when the bike is used like a conventional superbike. “In terms of power and efficiency,” says Simpson, “as well as the instant surge of torque that characterizes a really potent machine, it’s a recipe for the perfect superbike.”

Away from the track or fast roads, at low speeds, the bike can run in fully electric mode, with the rotary firing only when demands on the throttle exceed a certain threshold. It’s the same principle used by Yamaha’s HV-X concept shown in Tokyo last October—but far more elegantly packaged and with the emphasis on performance over economy.

Despite that performance bias, the Re:gen e-SBK will also have lower emissions than conventional four-stroke superbikes, claims Simpson. Decoupling the rotary from the rear wheel means the bike can run at its most efficient speed all the time—something constant load changes on conventional engines prevent. The bike will also regenerate some of its power under braking, and the near-omnivorous rotary can run on alternative fuels, including ethanol, methanol and biofuel, as well as regular unleaded.

Part of the bike’s clean looks stem from its use of a carbon monocoque chassis—a design that dispenses with a conventional frame in favor of super-stiff clamshell sections of structural carbon-composite. It’s a trademark of ex-Norton racer and engineer Peter Williams, who is closely involved with the project. Indeed, the Norton connection runs deeper—the bike was set to be an offshoot of the reborn Norton before it was agreed both projects should have their own distinct identities.

Simpson also plans an all-electric race version eligible to compete in electric race events, such as TTXGP, ePower or TTZero.