Quick search
Finally, after almost 5 years we can move on from the very popular and market leading Bosch CX (4th Generation).
The Bosch Performance Line CX motor has long been a standard-bearer for high-performance e-bikes, but its 2025 iteration marks significant advancements that set it apart from previous versions. Bosch’s newest model focuses on improving rider experience, integrating smarter sensors, reducing noise, and offering advanced braking technology, ensuring a leap forward especially for e-MTB enthusiasts.
Bosch CX (Gen 5) Specs:
- Motor Power: Peak 600 watts | Nominal 250 watts
- Torque: 85 Nm (Newton-meters).
- Assistance Levels:
- Eco: Up to 60% support.
- Tour: Moderate support for longer rides.
- Tour+: Dynamic mode that provides more progressive power based on input.
- eMTB: Adaptive mode with up to 340% support.
- Turbo: Maximum assistance, providing up to 340% of the riderโs power.
- Pedal Cadence: Supports pedal cadences of up to 120 RPM, with high power maintained up to 130 RPM.
- Weight: Approx. 2.9 kg (6.39 lbs), slightly lighter than previous generations due to the magnesium housingโ.
- Noise Levels: Reduced motor noise and minimized “rattle” compared to previous versionsโ.
- New Features:
- Hill Start Assist: Automatically holds the bike in position when starting on a steep hillโ.
- Walk Assist: Provides consistent assistance while pushing the bikeโ.
- ABS Pro: Updated for improved braking control, particularly for off-road and steep descentsโ.
- Battery Compatibility: PowerTube 600 Wh and PowerTube 800 Wh batteries.
- Smart System Integration: Boschโs Smart System.
- eShift Compatibility: Integrated support for automatic gear shifting with electronic drivetrains like TRP EASIโ
While a host of new features elevate the CX for hardcore off-roaders, its distinction from the Bosch SX motor makes clear that the latter is better suited for lighter, more efficient applications.
1. Refined Power and Sensor Technology
One of the most talked-about aspects of the new CX Gen 5 motor is its improved sensor system. According to various reviewers, the new CX motor is more responsive than ever, thanks to a combination of torque, cadence, and inertial sensors that measure input data at an impressive rate of 1,000 times per secondโ.
This sensory sophistication allows the motor to detect everything from steep inclines to minute vibrations, adjusting power delivery on the fly. Whether tackling technical climbs or smooth terrain, riders are assured of optimal traction and power, particularly through features like the new Hill Start Assist, which provides better grip on steep terrainโ.
This level of finesse sets the Performance Line CX apart from other motors on the market, which might struggle to deliver consistent support across varied conditionsโ. This precision is further bolstered by a new thermal management system, preventing overheating during extended climbs, and ensuring consistent power even in demanding situationsโ.
2. Reduced Noise, Increased Focus on the Trail
For some, the most appealing improvement is the reduction in mechanical noise. By decoupling the drivetrain components during descents, Bosch has significantly minimized the noise output of the CX Gen 5โ.
This quiet refinement contrasts with earlier versions, and itโs one of the features that stood out in early tests, according to E-Mountainbike Magazine, where testers reported that this decoupling greatly enhanced the motorโs appeal during downhill ridesโ.
3. A Game-Changing ABS System for Safety
One of Boschโs standout innovations is the new ABS Pro braking system. Bosch developed this technology in conjunction with e-MTB racers, leading to two distinct braking modes: ABS Trail Pro, aimed at casual riders who need maximum grip and stability, and ABS Race mode, designed for experienced riders who may want more aggressive control during technical descentsโ.
This allows riders to brake late and hard without the fear of skidding or losing balance, elevating both performance and safety on challenging trails. The inclusion of this system sets Bosch apart from many competitors, who lack this level of braking sophistication.
4. Purion 400: Compact Control at Your Fingertips
To complement the CX motorโs refined power delivery, Bosch has introduced the Purion 400 display. Smaller and more streamlined than the Kiox series, the Purion 400 strikes a balance between simplicity and functionality, with its 1.6-inch screen providing key data like speed, battery status, and power output.
The compact design makes it an ideal choice for e-MTB riders who prefer a less obtrusive, more minimalist cockpit. Positioned next to the stem, itโs protected from trail hazards, while still providing easy access to essential ride metricsโ.
5. Battery Power: The New PowerTube 800
A key upgrade in Boschโs 2025 lineup is the PowerTube 800 battery. With a capacity of 800 Wh and a significantly reduced weight of 3.9 kg, the PowerTube 800 offers more range while being lighter than previous modelsโ.
Compatible with other Bosch batteries, as well as the range extender, which allow users to push up to 1,600 Wh by pairing two batteries. This level of customization is ideal for e-MTB riders who embark on extremely long and/or challenging routes where range is a priority. But keep in mind, batteries = weight.
Bosch stepping in to 2025
Performance vs. Efficiency: The CX vs. SX Debate
While the Performance Line CX Gen 5 is built for e-MTB riders who demand maximum power and control in off-road environments, Boschโs SX motor serves a different purpose. The SX is designed with efficiency in mind, catering to urban e-bikes or lighter cross-country applications where sustained power isnโt as crucial.
The SX offers smoother, quieter rides on less technical terrain and provides a more energy-efficient option for commuters or casual riders. The SX is lighter, more compact, and built for bikes that don’t require the full range of high-torque performance that the CX offersโ.
A Year of Transformation for E-Bikes and Motors
As we look ahead, 2025 promises to be a pivotal year for the e-bike industry. Bosch is leading the charge with its new CX motor, but it wonโt be alone in making waves. Several (read: Nearly all) major e-MTB brands, including CUBE, Focus, and Norco, have already announced new models integrating Boschโs updated technologyโ.
Meanwhile, competitors are racing to introduce motors that can challenge Boschโs dominance, signaling a year of heightened innovation and competition. As brands like Yamaha, Brose, and Shimano continue to evolve their offerings, the landscape for e-bike motors is rapidly shiftingโ. New brands such as Hepha, DJI, Maxon and Mahle continue to push and catch up to the others.
The new generation of motors will set benchmarks for efficiency, power, and sustainability. With lighter motors, more compact designs, and smarter integration, 2025 is shaping up to be a year where riders have more choices than ever before. Bosch, with its proven track record and innovative spirit, remains at the forefront, but the coming wave of competitors will ensure that the next chapter in e-MTB technology will be nothing short of revolutionary.
Conclusion: A Future of E-MTB with Bosch
Across the board, the new Bosch Performance Line CX Gen 5 motor represents a major leap forward for high-performance e-MTBs. Reviewers have universally praised its smart sensor technology, quieter operation, and enhanced safety features. The new motor is expected to define e-MTB experiences in the coming years, especially for riders tackling technical terrain and long, demanding trails.
Boschโs innovations, from the Hill Start Assist to ABS Pro, make the CX motor more adaptable, durable, and user-friendly, while the Purion 400 display and PowerTube 800 battery add convenience and extended range.
For riders seeking a more lightweight, less intense ride, the Bosch SX remains a strong contender, proving that Bosch has developed a diverse ecosystem catering to a broad range of cyclists. Whether youโre conquering steep mountain passes or navigating city streets, Bosch’s electric drive systems continue to set the standard for reliability and innovation in the e-bike world.
