QJMotor’s Electronic Clutch

Jun 13, 2023

Clutch-by-wire offers new gear-change options.

There’s no question that the Chinese motorcycle industry has made huge leaps over the last few years but there are certainly still areas where it lags behind rivals from Europe, Japan, and America. One of them is innovation—China’s brands are masters of copying others and incorporating technology at lower prices, but they rarely introduce developments not seen elsewhere first.

That’s one reason a new patent from China’s Qianjiang—owner of QJMotor and Benelli, among others—is notable, as it suggests something that others have yet to adopt in the form of an electronically controlled clutch. Illustrated on the 700cc twin-cylinder engine of the QJMotor SRK700, which is also used on the Benelli TRK702, the electronic-clutch actuation promises several possible advances over the usual hydraulic or cable-operated clutches that we’re used to. And although this idea has yet to be implemented by another manufacturer, Honda filed patent applications for the idea back in 2021.

On the most basic level, such a unit promises to ease the design and manufacturing of bikes by eliminating the need to route a clutch cable or hydraulics from the lever on the bar to the clutch itself. It would still be rider-operated using a lever, but just as most modern bikes have no direct connection between the twistgrip and the throttle butterflies, the Qianjiang clutch would rely on electronics, with a potentiometer at the lever operating an actuator at the clutch. The actuator operates a drive shaft that turns a second rotating shaft by a few degrees via a sector gear. The second shaft is coupled to a pullrod that engages or disengages the clutch.

Qianjiang’s patent application focuses on the mechanical side of the clutch actuator’s design rather than exploring the system’s possibilities, but the potential advantages are clear. Although it still allows the use of a conventional-looking clutch lever, albeit a ride-by-wire one, the system could also be part of a semi-automatic or even fully automatic transmission. Alternatively, it could operate automatically for taking off from a stop and coming to a halt, and then use a conventional quickshifter to allow clutchless changes once you’re moving.

There have been several bikes over the years with automatic clutches, from the Yamaha FJR1300AE’s YCC-S in 2005, which used a fully automated clutch and electronic shifter, to the Rekluse-based centrifugal clutches on MV Agusta’s SCS system. And, of course, Honda’s DCT twin-clutch, seamless gearboxes also rely on computer-controlled clutches. However, the system that Qianjiang appears to be proposing differs from those in its operation and could be used to create a bike that’s able to operate in a variety of modes, mimicking a completely conventional manual one minute, giving the rider full control of the clutch as well as the gear shifter, but with the ability to operate completely automatically if that’s what you prefer.