Mahle X20 with Update: Still the Best Rear Wheel Hub Ebike Drive?

This summer, Mahle broke new ground to some extent. With the M40, the manufacturer with Spanish roots unveiled its first mid-drive motor. Until its presentation at Eurobike 2025 in Frankfurt am Main, the X20 rear wheel hub drive was considered the undisputed flagship. In the future, attention will be divided more evenly between the two. With an upgrade, the Mahle X20 now has new arguments with which it hopes to impress ebike manufacturers and ebike riders alike.

1. E-drive with a wide range of applications
2. Update boosts performance of Mahle X20
3. Work on algorithm and software
4. In future also on ebikes featuring UDH derailleur hanger

1. E-drive with a wide range of applications

A good three years ago, the X20 entered the market as one of the most advanced rear wheel hub motors, aiming to secure its share of the ebike segment. It wanted to become the first choice for ebikes that should weigh as little as possible and for which a less powerful assist would suffice. Naturally, e-road bikes, e-gravel bikes, and lightweight urban ebikes pursue such an approach. The system was used – or is still used today – by around 40 brands with illustrious names such as 3T, Desiknio, Konrad Bikes, Mondraker, Möve, Ribble, Rose, Schindelhauer, Scott, Storck, Urwahn and Wilier Triestina. The number of models is significantly higher and includes all three types of ebikes mentioned above. Given this track record, it can be said that the drive has certainly lived up to its objectives.

At the same time, we are talking about a drive that has hardly had any new components added or undergone any in-depth further development since April 2022. Therefore, a refresh does indeed seem appropriate. With the update now being presented, Mahle is focusing on two key aspects:

• increasing technical performance
• expanding the options for integration into ebikes

2. Update boosts performance of Mahle X20

Mahle is starting at the base of the motor and increasing its maximum power. From a previous 250 watts, this has now risen to 275 watts. That represents an increase of ten percent. According to the manufacturer, the increase is particularly noticeable at lower cadences. In this range, you will be able to get more power out of the motor than was previously the case. A diagram attached to the press release shows that at higher revolutions, the motor can deliver almost constant maximum power from a certain point onwards. As a result, you should not experience any drop in performance at higher pedaling frequencies.

Parallel to the peak power, the maximum torque increases to 65 Newton meters. This is noticeably higher than the previous 55 Newton meters. However, there is an important footnote to this 18 percent increase. It is not a measured value. Instead, Mahle calculates it based on its own formula. This converts the actual torque applied to the rear wheel into one that theoretically corresponds to that of a mid-drive motor. Surprisingly, Mahle does not reveal what this formula is. 😉

The manufacturer acted in exactly the same way in 2022 when the X20 was launched. At that time, it was possible to determine from the documentation that the former 55 Newton meters corresponded to a value of 23 Newton meters at the rear wheel. If we assume the same ratio, the 65 Newton meters would correspond to a measured torque of around 27 Newton meters.

3. Work on algorithm and software

Mahle appears to have achieved this gain entirely by electronic means. There is no mention of any structural changes. If you already ride an ebike featuring the Mahle X20, you can expect a boost in performance towards the end of 2025. Mahle has announced a gradual firmware update for this date. This also means that the weight of the X20 motor will remain unchanged at 1.4 kilograms. With the lightest of the compatible batteries, the 1.5-kilogram Mahle iX2 with a capacity of 250 watt-hours, this results in a total system weight of around 3.2 kilograms. For the larger battery, the Mahle iX3 with 350 watt-hours, an additional 750 grams would be added.

4. In future also on ebikes featuring UDH derailleur hanger

The second important change to the revised X20 system, on the other hand, cannot be transferred via new firmware. To achieve this, the motor has been equipped with new hardware. Thanks to this, it can be combined with ebikes where the derailleur is held on the frame by a Universal Derailleur Hanger (UDH). Developed by Sram, this derailleur hanger has become indispensable, at least in the field of e-mountain bikes. However, ebike manufacturers also install it where an electronic derailleur from Sram is installed as standard and compatibility with transmission derailleurs is a priority. In addition, the UDH derailleur hanger better protects the derailleur from damage in the event of a collision with stones or other solid objects.

Every new Mahle X20 drive will now be compatible with the UDH standard.

“This upgrade is about giving riders more choice in how they ride — whether they want more support on climbs, a more dynamic feel on flat terrains, or simply a smoother experience overall. We’ve engineered a solution that delivers enhanced performance without adding weight or complexity.”, says Jochen Sommer, Head of Mahle Smartbike Systems.

Mahle MX20 motor at a glance

• Continuous rated power: 250 W
• Maximum power: 275 W
• Assistance up to: 25 km/h
• Maximum torque: 65 Nm (approx. 27 Nm)
• Weight: 1.4 kg

Batteries, chargers, control untis and displays for the Mahle X20 e-drive

Pictures: 3T Cycling Srl.; Cyclesport North Ltd; Desiknio Cycles SL; Mahle Smartbike System; Rose Bikes GmbH; Urwahn Engineering GmbH