Kymco’s Simulated E Gearbox

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Kymco is working on the next generation of electric motorcycle technology. (Kymco/)

It was back in 2018 that Kymco first showed its SuperNEX electric sportbike, and followed it up a year later with the RevoNEX naked version. And while production hasn’t happened as quickly as originally intended, the models are still scheduled to reach showrooms at some stage in the near future.

Kymco’s patent drawings show what appear to be conventional gearshift lever and clutch, but they really just control the algorithms on the single-speed drive motor. (Kymco/)

However, a newly published patent application suggests that one of the bikes’ most intriguing elements—what appears to be a conventional manual transmission complete with foot-operated shifter and left-hand clutch lever—isn’t quite what it seems. While the SuperNEX and RevoNEX, which were revealed for a second time in redesigned form in 2022, have sparked a lot of intrigue with the promise of a riding experience more like that of a gas-powered bike, the new patent application shows that the gearshift system Kymco has designed is a simulation rather than a real clutch and gearbox.

It’s actually a more logical route to take. Most electric bikes don’t have a multispeed transmission for the simple reason that electric motors make their maximum torque at low speed, trading it off in favor of power as revs rise, eliminating the need for a complex multi-ratio gearbox that essentially does the same job for a combustion-engine motorcycle. We might like the physical sensation of changing gear and the perception of control that it gives, but it’s just not required on an electric vehicle. So why add the weight, bulk, and complexity of a clutch and gearbox, particularly given that electric bikes are already battling against the weight and size of batteries?

Kymco’s new patent shows that while the SuperNEX and RevoNEX have a completely conventional-looking clutch lever on the left handlebar and a similarly normal-looking shifter in front of the left-side footpeg, they’re actually connected—like the electronic throttle—to the control units that govern the behavior of the electric motor and of a sound-effect system designed to give an aural impression of a manual change.

Pulling in the clutch could instantly stop the regenerative braking, making the bike feel like a conventional ICE coasting. (Kymco/)

However, it might be a less digital experience than it seems, with some genuine advantages when it comes to riding that go beyond simply fooling your senses into believing you’re riding a manual-transmission bike. The gear “ratios” for instance, might simply be preprogrammed maps for the bike’s electric motor, but seen in another light it’s a system that offers a way to switch rapidly through the sort of “modes” that many electric bikes already have. The lower gears will put the emphasis on low-speed torque and acceleration, for example, and the clutch will give a natural-seeming way to engage or disengage drive.

The shift lever could theoretically be set up however the rider prefers, one-down, five-up, or the opposite race-style pattern. (Kymco/)

The impact might be even more noticeable during deceleration, with different regenerative charging settings for each “gear,” and the ability to disengage the regen effect instantly by pulling in the clutch lever, so the bike coasts more easily. Drop into a lower simulated gear and the engine-braking effect will be increased, just as it is on a normal combustion-engine bike. In this light, the sound-effect system also becomes a useful tool, offering the rider an aural indication of the “gear” that’s selected and whether the bike is in a relaxed high-gear mode, or a frenetic low-gear setting. Kymco’s patent also illustrates and describes a “virtual speed” indicator on the dash, essentially a faux rev counter, to give a familiar visual indication of which artificial gear you’ve selected.

A faux rev counter could give the rider a sense of how the motor is acting. (Kymco/)

By using a purely electronic clutch and gearshift, there’s also the scope to add a completely automatic, single-gear riding mode—like most other electric bikes—or to play with the number of “gears” available or even alter the shift pattern. Kymco’s patent document suggests the shift could be changed between a conventional pattern (down for first, up for neutral, second, third, etc.) or a layout with neutral at the bottom and upward movements for every ratio from first to top. Presumably, it would be similarly easy to change to a race-style, upside-down shift pattern if that’s your preference. And it’s all done without adding any extra weight or bulk other than the electronic clutch lever and foot lever.

Although the SuperNEX and RevoNEX missed their original planned production date of 2021, it’s clear Kymco is still working on the project and the bikes are intended to reach showrooms at some stage in the not-too-distant future. When they do, the transmission is sure to be a major talking point, and perhaps even the killer feature that makes them more appealing than rival models.

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