Bosch Ebike Novelties 2025: Quieter Motor, Larger Batteries and Even More

With its novelties at Eurobike 2024, Bosch has left many people somewhat undecided. One question in particular cropped up repeatedly on social media: Could this be everything? The answer is no. And the manufacturer is making a strong case for it. For the 2025 season, in addition to new eShift options, a new riding mode and other digital features, there will now be a revised top-of-the-range motor, two new intube batteries, a new display and another version of the ABS for ebikes.

After a whole host of new software, it’s now time for the hardware to catch up. The dominant theme is clearly the fifth generation of the Bosch Performance Line CX. It ties in with the presentation of the first generation at the Eurobike show in Friedrichshafen in 2015. Even today, this marks a very special moment in the history of the system manufacturer. For Bosch, it is representative of the beginning of truly sporty ebike riding. The tenth anniversary of the Gen.1 presentation will be in 2025. And so these ten years of Uphill Flow are the guiding theme for the new products.

1. Bosch 2025 season – the new motor
2. Bosch 2025 season – the new batteries
3. Bosch 2025 season – the new display
4. Bosch 2025 season – the new ABS

1. Bosch 2025 season – the new motor

Unfortunately, we don’t have any absolute figures to back this up. Nevertheless, the Performance Line CX from Bosch is likely to be the most frequently installed motor in ebikes in Europe. If not worldwide. In this respect, the Gen. 5 – or BDU384Y according to Bosch’s internal nomenclature – has big shoes to fill. If you look at its technical data, it doesn’t go beyond that. The torque remains unchanged at 85 Nm. From a speed of 25 kilometres per hour, the motor assistance is no longer available. Until then, it provides a maximum of 340 per cent of the energy you input into the system via pedalling. Ok, the weight has been reduced by 100 grams to 2.7 kilograms. But when it comes to the riding modes, you’ll still find the familiar Turbo, eMTB, Sport, Tour+, Tour, Eco and Auto.

So where is the actual development hidden? Well, it’s clearly under the magnesium housing, which is still black. There, one of the most significant revisions gives the new Bosch Performance Line CX a quality that many of you have previously missed in the motor. Silence. No complete silence, not that. But on the first test rides, the Gen. 5 is quieter than ever before. Apart from an amazingly constant, pleasantly deep continuous tone across all levels of assistance, nothing noticeable can be heard from the new unit. No rattling. No clacking. No ratcheting. Nothing.

Separate drive trains

The reason for the new smoothness are changes in the design. When the drive is running without load, the external drivetrain with chain, chainring and cassette decouples from the internal drivetrain with freewheel, gearbox and motor. And bada bing bada boom, the annoying noises that may have caused some of you to change motors are a thing of the past. Time will tell how well Bosch’s trick works in the long term. Our first impression: This problem could actually be solved.

New sensors for more intelligence on the Gen. 5 CX motor

Bosch has also improved the motor’s sensors. Cadence sensors and torque measurement technology are supplemented by inertial sensors on the new model. These not only measure acceleration and speed in six dimensions, but also detect gradients and angles of inclination as well as vibrations. Based on this data, the ebike system has an exact idea of whether you are currently riding uphill or downhill, for example, and whether the ground is rather rough or flat.

You will benefit from the new motor’s information advantage especially when mountain biking with an eMTB. The first example of this is the new hill start assist. Imagine you are on a technically demanding ascent. At one point, you get out of sync, have to stop and then want to continue up. It is very steep and you may already have the next difficulty in view. So, you have little time to lift your supporting foot, put it on the pedal or click it in and get back to a controlled pace. In this situation, you can activate the new hill start assist at the push of a button. It briefly prevents the bike from rolling backwards and gives you the time you need to get your foot on the pedal. It may sound unspectacular in theory. However, in practice it makes the difference between continuing your ride and having to get off and push. Especially since the motor, after restarting, precisely meters its power so that you always maintain traction.

A kick makes all the difference

The second improvement concerns the further developed Extended Boost. In the case of the Performance Line CX, Bosch understands this to mean the brief response of the motor to an active pedal kick. You can use this, for example, when you roll up to an obstacle in neutral and get a brief push from the motor just before or while you are riding over the obstacle to help you get over it. This kick, the Extended Boost, reacts much more sensitively than before. The motor registers exactly how strongly and how long you apply the impulse and gives you the equivalent in support. With a little practice, this is a very helpful tool that you will be amazed at how often you can use.

The more extensive measurement of the sensors also has an additional effect on the walk assist. Its speed now synchronises better with your walking speed. Instead of mindlessly rolling along at six kilometres per hour, it registers your pace and adjusts accordingly.

Proven virtues of the Bosch Performance Line CX

Of course, Bosch did not develop and construct the motor from scratch. Therefore, the features of earlier versions also apply to it. This includes, for example, its resistance to the heat that is generated inside it during heavy continuous use. According to the manufacturer, the Performance Line CX is still superior to the competition in this respect when it comes to maintaining maximum power at 100 per cent for as long as possible.

The design similarity also extends to the connections. In addition to the connection for the battery, there are five further ports:

• HMI/display
• Front light
• Rear light
• ABS/HPP
• LPP

The parallels to the Bosch Performance Line SX should also be mentioned. Bosch has transferred some of the developments contained in it to the Gen. 5 of its big brother. This includes, for example, the pedal resistance, which has been reduced by around 30 per cent compared to its predecessor. Both also have the universal frame mount for the motors in common. This involves two socket head bolts that hold the motor on the drive side. On the non-drive side, there is a plain bearing opposite this. This compensates for the frame mounting tolerance. This design will be used in all future motors.

Bosch Performance Line CX (Gen. 5) at a glance

• Nominal continuous power: 250 watts
• Peak power: up to 600 watts
• Assistance up to: 25 km/h
• Torque: maximum 85 Nm
• Max. assistance: 340 %
• Variants: hub and derailleur gears
• Weight: approx. 2.7 kg

2. Bosch 2025 season – the new batteries

The technology transfer from the SX ecosystem to the new CX ecosystem continues with two new batteries. Both the Bosch PowerTube 800 and the Bosch PowerTube 600 not only contain the 21700 battery cells already used in the Bosch CompactTube 400, they are also arranged in a very similar way. Both new batteries, which can be accommodated in the frame tube, are therefore significantly lighter than their counterparts, the Bosch PowerTube 750 and the Bosch PowerTube 625.

At 3.9 kilograms, the new PowerTube 800 weighs around 400 grams less than a PowerTube 750. When comparing the PowerTube 600 and PowerTube 625, the difference increases to 600 grams. If you look at the energy density of the batteries, i.e. the ratio of watt-hours to kilogram, you will see that the Bosch PowerTube 800 achieves a new Bosch-internal record here with 205. The PowerTube 600, with an energy density of 200 watt-hours per kilogram, is only just below and on a par with the CompactTube 400.

Modular template for bicycle manufacturers

In terms of dimensions, Bosch has chosen a middle way. To ensure that the two newcomers can be interchanged, the overall length in both cases is 430 millimetres. For the Bosch PowerTube 800, this means that it is about five centimetres shorter than a PowerTube 750. At the same time, the Bosch PowerTube 600 is 15 millimetres longer than a PowerTube 625. This allows bicycle manufacturers to work with two different sized battery mounts in their models. The larger version fits both the PowerTube 800 and the PowerTube 600, while the smaller version only fits the PowerTube 600. If the first version is installed, the two intube batteries can be exchanged later as desired. If the second version is chosen, the bike manufacturer can design the down tube to be slimmer when constructing the frame and focus entirely on the design.

However, due to the new dimensions, the new PowerTubes, which will be available in silver, are not compatible with previous PowerTubes.

Bosch PowerTube 800 at a glance

• Capacity: 800 watt hours
• Weight: 3.9 kilograms
• Dimensions: 430 mm x 75 mm x 81 mm
• Compatible with DualBattery: yes

Bosch PowerTube 600 at a glance

• Capacity: 600 watt hours
• Weight: 3.0 kilograms
• Dimensions: 430 mm x 75 mm x 69 mm
• Compatible with DualBattery: yes

3. Bosch 2025 season – the new display

The Purion 400 brings more variety to accessing the edrive. For the first time, Bosch is placing a display in the handlebar and stem triangle. With the help of a clamp, you can mount it on the right side of the stem on the handlebar. The clamp is available for typical handlebars with diameters of 31.8 and 35 millimetres.

Bosch didn’t choose the name at random. Purion 400 and Purion 200 both use the 1.6-inch screen. However, the Purion 400 is less exposed on the bike. Its position in the angle between the handlebars and the stem means that it is much better protected in the event of a crash. Another difference becomes apparent when you look at the buttons. The new display has none at all. It therefore inevitably requires a combination with a control unit – either the LED Remote or the Mini Remote. In theory, it would also be possible to use the Purion 200. However, hardly any bicycle manufacturer is likely to choose this combination. It would somehow be redundant, wouldn’t it?

Bosch Purion 400 also an acoustic signal generator

Compared to the Purion 200, the new Purion 400 has another small advantage. It can send signals for acoustic notifications via an integrated loudspeaker. Otherwise, understandably, many features are similar. For example, it shows you the following data in real time:

• Riding speed
• Battery charge level
• Selected assistance level
• Distance travelled
• Cadence
• Power
• Heart rate
• Heart rate zones

According to Bosch, the display will be available in stores from October/November. Then you can retrofit it to any ebike featuring the Bosch Smart System, provided that the necessary control unit is already installed or that you retrofit one as well.

4. Bosch 2025 season – the new ABS

Two years ago, Bosch introduced one of the most useful components of the new Smart System with a completely redeveloped anti-lock braking system for ebikes. At least from our point of view. Tailored to four different use cases – ABS Cargo, ABS Trail, ABS Allroad and ABS Touring – you could even say there are four different ABS systems. Since then, bicycle manufacturers have been increasingly accessing these components and integrating them into a number of models. This is mainly because the system has proven to be an effective means of increasing riding safety.

Redefining the limits

Despite the variety described, Bosch apparently still saw potential for improvement. That’s why a second version – the Bosch ABS Pro – is being released for the 2025 season. It complements the previous ABS, but doesn’t replace it. You’ll find it primarily on selected enduro eMTBs. After all, it comes from exactly this sector. Bosch developed the ABS Pro together with and for professionals who compete in racing series such as the Enduro World Series for E-Mountainbikes (EWS-E).

And their requirements for an ABS are clearly different from those of typical cyclists. It’s about pushing the absolute limit. Braking as late as possible. Pulling the brake lever as hard and briefly as possible. All in the fight for tenths of a second. Even sceptical athletes were quickly convinced, according to what we heard. Understandably so, considering that a one-percent shorter ride time can mean the difference between finishing in the top ten or on the podium. At the same time, you can ask yourselves how important it is for you to be one percent faster than before.

Two selectable modes

ABS Pro is based on an updated control unit. Visually, it can be easily distinguished from conventional ABS by the prominent cooling fins at the top. Overall, it has become a bit slimmer and lighter. Nothing significant has changed in the internal structure. Bosch has publicly disclosed modifications to the valves and the size of the storage chambers. The rest remains a well-kept secret.

You can ride the ABS Pro in two modes: Trail Pro and Race. Basically, the response behaviour has been optimised in both. It allows for more aggressive braking and decelerates correspondingly faster without the front wheel slipping more. In addition, the system no longer recognises it as a danger when the rear wheel loses contact with the ground. So, if you have the necessary skills, you can try stoppies and short wheelies on the front wheel despite ABS.

Improved conditions for market penetration

The system can be switched on and off at any time while riding. According to Bosch, more suspension forks will be available in the coming years that the ABS Pro can be attached to using a direct mount. In the past, compatibility with relatively few suspension forks proved to be a bottleneck when it came to implementing ABS on ebikes. So far, there are officially two brake manufacturers that have committed to offering a compatible product: Magura offers the MT7 and TRP the DH-R Evo. Since recently, an overview in the eBike Flow app shows you how often you actually use the ABS in the end. It registers every time the system is activated and shows you the proportion of the corresponding braking manoeuvres as a percentage. The Kiox 300, Kiox 500 and Purion 200 displays also show information such as braking distance and braking duration. The new Purion 400 will only receive these functions at a later date.

Those who are now rejoicing and want to start looking for a retrofit kit for the ABS Pro can forget about it right away. Bosch supplies the system exclusively to bicycle manufacturers. It will not be offered as a single set in stores.

Pictures: Bosch eBike Systems; Elektrofahrrad24 GmbH