Update for Bosch motor available: Upgrade Bosch CX: 100 Newton metres and 750 watts

The arms race for the most powerful e-bike motor has begun! While the relevant e-drives have been relatively harmonious for years with around 85 to 90 Newton metres and a maximum peak power of 600 watts, the top dogs are currently outdoing each other with new highs. The drone specialist DJI appears to be using the extremely powerful Avinox motor The Chinese motorcycles seem to have triggered a craving for maximum performance among e-bikers. In terms of performance and weight, the Chinese have pulverised the existing range. Bosch has now not only presented the exclusive top-of-the-range Performance CX-R motor. No, just in time for the start of the Bike Festival in Riva del Garda, the Swabians are also giving their popular Performance CX a proper power update.

As much power as the new Bosch CX-R e-bike motor

750 watts of peak power, 100 Newton metres of torque, 400 percent support - this is what every current Bosch Performance CX (Gen5, BDU38) should soon be able to deliver. Previously, it was 600 watts, 85 Newton metres and a maximum of 340 percent support. This makes the CX just as powerful as the all-new Performance CX-R.

The CX is still some way off the fabulous values of the DJI motor (850 watts in normal operation, 1000 watts at the peak), but it is clearly getting closer. In terms of performance, Bosch could be roughly on a par with of the new Specialized S-Works motor in the new Turbo Levo which, however, is significantly heavier at a good 3.1 kilos. The Performance CX weighs in at 2.85 kilos.

Download more power for free

The good news for many Bosch drivers: The new features are coming via a free update, which Bosch has announced for July 2025. Anyone can install the new software "over the air", i.e. at home via the Bosch app on their Performance CX. After the update, the setup will initially remain at 600 W and 85 Nm as standard. If you want to utilise the full power, you can fine-tune the power, torque and assistance to your personal preferences in the app and thus call up the new maximum values.

However, Bosch also sends a warning after the performance promise: The manufacturer points out that higher power and torque values put more strain on the mechanical components such as the chain and cassette and also affect the range - the more power, the higher the wear and the shorter the tour, according to Bosch.

This is only logical - and probably also a reason why the maximum values first have to be activated manually in the app. The default settings remain 85 Newton metres and 600 watts even after the update. In addition, the 100 Nm update requires approval from the bike manufacturer for the respective bike model. Theoretically, this can limit torque and power. For example, because they do not consider the installed components to be robust enough.

What the software update for the Bosch Performance Line CX motor brings

• More power and torque: according to Bosch, the Performance CX can deliver up to 750 watts (previously 600 W), 100 Newton metres of maximum torque (previously 85 Nm) and up to 400 percent support (previously 340 %) after the update.
• The maximum values (600 W power, 85 Nm, 340% support) remain in the standard setup. The maximum thrust can be activated in the app if required.
• The new E-MTB+ mode is intended to lie between the familiar E-MTB mode and the aggressive Race mode of the CX-R. It reacts strongly to the rider's input and is intended to release up to 400 per cent support. Bosch wants to switch between fine modulation and extreme thrust with long coasting depending on the situation.
• Race mode remains the exclusive preserve of the CX-R
• Update to be available from July 2025

E-MTB Plus: New dynamic mode

In addition to pure power, Bosch has also further tuned its hobbyhorse: the tuning of the motor is said to have moved up another level. The E-MTB+ mode is a new support level. It is a further development of the E-MTB mode, so to speak. Its idea is to strongly link the power delivery to the rider's pedalling impulse. If the rider pedals hard, the motor also accelerates, while only a subtle motor boost is released when pedalling at a leisurely pace.

The new E-MTB+ is designed to work even more dynamically than the familiar E-MTB mode and adapt even better to the conditions on the trail. Bosch calls the new sensor technology "Dynamic Control". The Swabians promise a kind of traction control within the new mode, which should ensure that propulsion remains confident and controlled even on demanding terrain and wet surfaces.

E-MTB+ provides up to 400 per cent support (E-MTB maximum 340%) and even the maximum overtravel of Race mode in the right situations. The new U-stage could therefore be described as a particularly sensitive Race mode - or as a super dynamic E-MTB mode. Compared to the classic E-MTB mode, the "Plus" is more powerful and even more lively and therefore even more geared towards trail fun. While the familiar mode is more focussed on touring and range.

Do you need the new Bosch Performance Line CX-R motor?

The Bosch Performance Line CX motor is therefore getting a series of exciting updates. So what is the difference between the classic CX with the Power-Plus and the brand new and exclusive CX-R? Not much, to be honest. In addition to the weight saving of around 100 grams (titanium axle!), the CX-R also has the more aggressive Race mode exclusively. This works extremely directly and offers even more support for maximum acceleration in many situations.

It also continues to push at full thrust right up to the switch-off limit. The extended boost has been lengthened and is intended to help you over root passages and steps even more playfully. Even if this is certainly a successful feature on the most extreme climbs, the vast majority of e-mountainbikers will probably be able to do without these refinements. Especially as the new E-MTB+ mode also gives the CX the special Extended Boost feature.

The new top tube display: Bosch Kiox 400C

It was an open secret that Bosch had a new display up its sleeve. After all, there was a hole in the top tube of many new Bosch bikes that was far too large for the system controller fitted. Now it's here, the Kiox 400C. And at first glance, it does what many other manufacturers have done before: The most important riding data on an unobtrusive and well-protected screen in the top tube. Power, cadence, heart rate, altitude metres and more: the new Kiox 400C displays these values on various, individually configurable data pages.

To keep your hands on the handlebars at all times, the displayed data changes automatically on request, adapted to the current riding situation. This is called Bosch Dynamic Screen. For example: uphill the altitude metres ridden, downhill the speed. The various display pages can be customised in the display configuration of the E-Bike Flow app.

The tactile buttons on the display can be used not only to switch manually through the screens. Theoretically, they can even be used to operate the motor completely. Minimalists could therefore completely dispense with a separate remote on the handlebars. For tech junkies, there is a sealed USB-C port for charging a sat nav or mobile phone on the Kiox 400C. The screen automatically adjusts to the brightness and a navigation display is also on board. Hardly any other top tube display can do this.

Already tested: This is what the power update for the Bosch Performance Line CX feels like

We were able to test the new software in the field before the official launch. Thanks to the free adjustment of torque and peak power in the app, you can feel the effect very well in direct comparison. It is clear that the increase in power and torque is clearly noticeable and takes the thrust of the Performance CX up a notch. Viewed in isolation, the power of the CX doesn't feel like a whole new level. However, in the "back-to-back test", the extra torque is impressively noticeable. The motor pushes over obstacles much more impressively when pedalling slowly or in too high a gear. The 25 % more power is also more than just a small plus.

These two factors together make the Performance CX even more dynamic. This is because the thrust is more powerful at a low cadence, making it easier to accelerate. And at the top, the motor gives you the feeling that you can always go one better. In fact, Bosch has managed to go one better in the discipline that they already master.

EMTB+ - the new super mode?

The improved riding experience culminates in the new E-MTB Plus mode. The dynamics of this mode are unrivalled. With light and even rider input, the new level provides very discreet and well-dosed support. If you pedal harder, the CX really revs up and pushes with up to 750 watts and 100 Newton metres of torque on request. In combination with the 400 % support, E-MTB+ feels much more powerful than the familiar E-MTB mode.

Extended Boost - lively, powerful and yet sensitive

On top of this comes the newly tuned Extended Boost. Bosch coined this term when introducing the Performance CX Race. It refers to a particularly long overrun. This means that the motor continues to push strongly and dynamically after the last pedal stroke - for up to two metres. This helps very effectively over steps and obstacles in off-road terrain and makes completely new manoeuvres and riding techniques possible. The "problem" with Race mode: coasting and thrust are so extreme that they can literally throw you off course and are not always easy to control.

In the new E-MTB+, the Extended Boost is released according to the situation. The nervous twitching and pushing when stationary, which can sometimes be quite annoying in Race mode, is completely eliminated. However, the motor responds to strong acceleration with the same concise coasting that makes Race mode a beast on the climbs. An excellent mix! These parameters make the new E-MTB+ mode the absolute benchmark when it comes to riding fun and control on demanding climbs. Bosch's marketing slogan "Uphill Flow" applies to the Performance CX with the new software more than ever.

BIKE summary of the Bosch power update

"The Bosch updates take the Performance CX to a new level. The extra torque and power gives you more options on the climbs - even if Bosch clearly falls short of the super-power of the DJI Avinox. The highlight for me, however, is the extremely dynamic E-MTB+ mode. Bosch sets the benchmark when it comes to fun and control on tricky climbs. No other motor combines sensitive modulation and lively power as brilliantly as the Bosch Performance CX. This applies more than ever with the Performance update!" - Florentin Vesenbeckh, Deputy Editor-in-Chief BIKE Magazine