Here's How Yamaha Fakes a Throttle Blip In Its EV-Motocross Bike

Why would an electric bike need a clutch? For very good reasons, actually.

By: Robbie Bacon

Apr 29, 2024 at 9:20am ET

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Electric motocross bikes, like the Stark Varg, are proving to be formidable machines against even the most modern 450s. So much so that the FIM banned them from competing in the same class. No manufacturer could compete with the 80 horsepower that's instantaneously on tap during the holeshot.

It's time to adapt or die.

But there's one area the Stark Varg can't compete with a conventional motocross bike: the clutch, or rather the lack of one. You see, to fire out of supercross berms or keep the front wheel pointed skyward over rough terrain or a set of whoops, riders are either dumping or feathering the clutch to keep the bike dancing.

The clutchless operation of the Stark is one of the few things riders say that hold them back from doing everything they normally could. Well, whenever Yamaha launches its first electric motocross bike, it looks like it'll have something that resembles a clutch.

Here's how it'll work.

The Patent

Last month, we learned that Yamaha has a new patent application, which relates to a motocross bike, specifically relating to how to design a transmission to improve traction.

But, more recently, Cycle World reported that Yamaha filed a new patent relating to how the bike's transmission would work without a conventional clutch but something that performs the same duty.

The patent shows the transmission from Yamaha's electric trials bike, the TY-E, with the clutch and flywheel eliminated and replaced by a set of springs between the motor and transmission. The purpose of these springs is twofold. Firstly, the springs should help soften the rapid response of an electric motor, and secondly, they can be used to temporarily store energy.

According to Cycle World, when the rider dumps the throttle, the springs compress and store energy. Then, they extend again to release the energy, which is combined with the maximum output of the motor to give a short boost of power. So, if you need to pick up the front end, as you normally would by blipping the throttle with a clutch, this should produce the same result.

I reached out to a member of Yamaha Motor Corporation U.S.A's press team, enquiring about when we might see a prototype electric motocross bike from the brand. He responded by saying,