ZF CentriX Review

The new ZF CentriX motor is almost as compact as a beer can and delivers a powerful 90 Nm of torque. We’ve put the system through its paces in an initial test to see if it has potential.

To ensure the axially aligned construction of the motor works, ZF uses a wave gear. This type of gear is primarily known from the drivetrain specialist Harmonic Drive and was originally developed for robotics to control rotational movements without play and with precision. In the CentriX motor, the wave gear sits on the same axis as the e-machine and transmits the motor’s torque to the drive shaft with just one gear stage.

This setup is also intended to give the motor a particularly high efficiency. In most e-bike motors, the e-machine and the drive shaft sit on two different axes and are connected via a planetary gearbox. Although a wave gear is unusual in e-bike motors, TQ has been using this gear concept since the powerful HRP120, as well as in the new HRP50.

Innovation number three is the system’s voltage. The system operates at 48V. For comparison, Bosch’s Performance Line CX system runs at 36V. The higher voltage reduces resistance in the system, which is supposed to generate less heat in the motor.

Efficiency is also expected to benefit from reduced resistance losses. A 48V system is not entirely new: the predecessor, which was marketed under the Sachs brand, was already based on a 48V system – just like the Brose Drive³ Peak motor and also the new DJI Avionix.

Building a compact motor is one thing. Unlocking 90 Nm of torque and 600 W peak power from such a compact motor is another. It’s a combination that can backfire when heat builds up in the compact casing. The art lies in heat management.

With the 48-volt system, ZF aims to reduce heat development due to a lower current flow. Additionally, the wave gear rotates through an oil bath, which is meant to lubricate the system on one hand, and also to absorb and dissipate heat.

To ensure the motor withstands extreme loads over a long period, ZF has integrated a overload clutch—a kind of torque limiter similar to a torque wrench. If the maximum allowable torque is exceeded, the clutch engages, protecting the system from overload-induced damage.

The topic of battery size divides e-bike riders like few others. Some are satisfied with compact batteries for their daily after-work rides, while others are driven by range anxiety to opt for the largest possible battery. However, everyone agrees on one thing: a lightweight e-bike is a blessing on the trail. And a lower weight usually comes from smaller batteries.

The Battery Rail from ZF is now set to make this choice easier for e-bikers, as there is no longer a need to commit to a single battery when purchasing an e-bike. The Battery Rail is a rail that is permanently mounted in the frame and onto which the battery is attached. Additionally, the rail is designed to secure the battery so stably that system failures due to contact loss are a thing of the past. The battery is secured at the lower end of the Battery Rail with a battery lock. The battery and lock are concealed under the battery cover – at least on the demo bike, the new Raymon Tarok.

The rail and battery, as a combo system, allow for either battery option. One is a 4.2 kg 756-Wh battery, the other is a 3.2 kg 504-Wh battery. Those who want to indulge in luxury can purchase both batteries and choose the appropriate one depending on the tour. For a short after-work ride, you can benefit from the low weight of the small battery, while for a long day tour, you can enjoy the extended range of the larger battery.

The main interface between the rider and the bike is the Core Controller. It sits in the top tube and offers all the functions needed to operate the E-System. The ZF System can also be used in a minimalist way, without a remote and display.

Additionally, the Core Controller features a magnetic charging port – similar to Apple’s MagSafe system. Through this charging port and the accessory cable, a smartphone or light can be powered by the main battery during the ride.

The Pure Remote is a simplified remote control for the left side of the handlebars. Compared to the Core Controller, the Pure Remote also allows the use of the walk assist.

If you want to have all the info at a glance while riding, mount the 2.8″ color display with touchscreen. This display also supports navigation, though only in a turn-by-turn format, guiding you from one turn to the next.

And of course, there’s the ZF App, which allows you to customize the motor and its characteristics individually. Additionally, updates for the motor system can be transmitted “Over The Air” via the app.

The operation leaves nothing to be desired. The feel of all control elements is pleasant and well-defined. The buttons on the Pure Remote are easy to reach, and the pressure point is noticeable.

The display quickly and accurately responds to finger touches—just as we’re accustomed to with smartphones today. The information is easy to see and read. An exciting feature is the front screen, which shows both the current motor output and your own power output.

ZF presented us with a near-production version of the ZF Bike Eco-System featuring the CentriX motor unit during a press event. Nonetheless, ZF emphasized the pre-production stage of the drive system and specifically referred to the software, which is not yet market-ready.

Now, let’s hit the trails. The motor responds lightning-fast to the rider’s pedal input, making starts on steep ramps and loose ground a breeze. The acceleration is impressive. The combination of 600 W peak power and 90 Nm torque provides solid pull-through. The motor truly excels uphill.

Unlike many other motor systems, this motor delivers strong push even at low cadences. The power output is particularly noticeable in the 0 – 15 km/h range. Those tackling steep ramps and technical trails will appreciate the substantial support. “Punch” is certainly the most fitting word to describe its acceleration characteristics. However, as you climb higher, it feels as though the motor lacks a bit of punch. This isn’t actually true – it just feels that way because the acceleration from a standstill is so pronounced that the wow factor doesn’t carry through as you reach higher speeds.

The characteristics of the motor particularly impressed me on technical uphills. You’re not forced to maintain a high cadence to tap into the motor’s power. Rapid pedaling can feel hectic in some terrains, causing you to lose focus on the trail. The ZF manages to provide strong assistance even at low cadences, allowing me to concentrate fully on the ride.

The distinctive engagement of the motor is accompanied by an equally distinctive soundscape. Compared to the most common full-power motors on the market, the ZF CentriX seemed louder to me—though a precise noise measurement wasn’t possible. The sound of the motor doesn’t have the high-pitched frequency of many other motors—it sounds less electronic and more mechanical: distinctive, powerful, robust—that’s how I would describe the soundscape.

The robust sound could be due to the wave gearbox, which involves multiple teeth engaging simultaneously in a kind of toothed drum. Apart from the motor noise, the system is whisper-quiet when the cranks are stationary, and you head into the downhill. There’s no annoying rattle to be heard on the ZF motor.

For end consumers, it might not be a big deal, but for dealers, it’s a blessing: the sleek wiring of the ZF Bike Eco System. To minimize the number and length of cables, ZF has opted for a smart arrangement of plug sockets. All electronic components facing forward are plugged into the Core Controller in the top tube.

All components located in the middle of the frame or pointing backward are plugged into the lower battery mount—it goes by the name “Battery Terminal.” This way, only one cable runs through the down tube—from the Core Controller to the Battery Terminal. All connections are simply plug-and-socket assemblies.

The plug sockets in the Core Controller and the Battery Terminal also allow for extensions with electronic accessories like a lighting system.

Currently, the new motor is exclusively available in the Raymon Tarok models. The delivery of the bikes will likely take until the second quarter of 2025. We’ve already checked out the available equipment variants for you. With the arrow symbol, you can also compare these to examine the different equipment features. This comparison is also possible with any other bike from our extensive market overview.