Mavic reveals lightweight motor that could lead to sub-10kg electric bikes

Mavic has launched its first e-bike drive unit, the X-Tend. Designed for e-road and e-gravel use, the French brand claims the e-motor is the lightest system currently available, enabling complete bike builds of under 10kg. 

Weighing just 1.2kg and compatible with most standard cranksets, the fully integrated unit allows for frame designs that closely resemble those of traditional road bikes, according to Mavic, with Q-Factor measurements and front derailleur shifting unaffected. It also features a built-in power meter, with a claimed +/- 2% accuracy.

The launch of X-Tend is the biggest development from Mavic since it was rescued from receivership by the Bourrelier Group in 2020.

Development  of the X-Tend pre-dates the takeover, with Mavic saying that it's been four years in the making and with some 120,000km of testing in the field. And if you're thinking that a foray into cycling electronics is strange for a brand most closely associated with wheels and clothing, then you probably haven't heard of Mavic Zap - a mid-1990s electronic shifting system that pre-dated Shimano Di2 by a decade-and-a-half! 

X-Tend is said to deliver 250 watts of normalised power and up to 390 watts of peak power with 37Nm of torque that can be temporarily boasted to 50Nm. The 360Wh battery weighs an additional 1.8kg, taking the overall weight of the system to 3.2kg including the power meter and bottom bracket bearings. For comparison the TQ HPR50 system that features on the best electric bikes from the likes of Pinarello, Trek and BMC tips the scales at 3.9kg.

Given that the TQ-HPR50 is regarded as the lightest mid-drive motor available, helping making e-bikes such as the 11.2kg Pinarello Nytro possible, Mavic’s assertions that a sub-10kg machine becomes fact rather than fiction when using an X-Tend  motor may well prove to be legitimate. Until now, e-bikes weighing less than 11kg have been hub driven, typically using Mahle’s lightweight system.

As with other comparable systems, a range extender is available for the X-Tend, which is designed to fit neatly into a dedicated bottle cage and provides an additional 180Wh at the cost of an extra 1.2kg.

Producing a lightweight system is clearly central to Mavic’s design. It states that the relatively slow growth of e-road bikes, when compared to the urban and mountain bike sectors, is largely due to the weight disparity between ‘acoustic’ and ‘electric’ machines that has an adverse effect on the e-bike’s overall ride quality in comparison.

As well as reducing weight, the X-Tend is also designed to be highly efficient whether it’s in use or not. Mavic says its custom brushless motor and frictionless clutch mechanism creates no residual friction when not in use and limited friction when it's on. The result is what Mavic describes as a “superior range of use”, which it says can equate to a 3000m climb, or roughly twice up the Col du Tourmalet.

Mavic also boasts that the X-Tend rides “like a regular road bike”, which is often seen as the holy grail for all e-road bikes. How it achieves this “supernatural” riding sensation is left somewhat unexplained, although it’s fair to assume that the combination of the aforementioned low weight, mid drive position and low friction are substantial contributing factors. Certainly mid-drive motors typically deliver their power more smoothly than hub motors, which can be a tad jerky.

So where are we likely to see the Mavic X-Tend system appear first? With it’s R&D a product of a partnership with BMC, it’s surely odds on that the Swiss brand will adopt the motor, perhaps in the next iteration of its RoadMachine AMP X? However, production models are unlikely to appear until 2025 at the earliest.