Interview on the new Bosch Performance Line CX: Is the fast charger coming back? Rattle-free SX motor?

EMTB Magazine: Top modulation and fine response behaviour - these are the strengths of the Performance Line CX. These characteristics have been further improved in the latest model. What is the secret behind this?

Sean Fingerhut, Product Manager Bosch Performance Line CX: One of the most important features of the Performance Line CX for us is the outstanding riding experience. We work on the smallest details to ensure that the motor does exactly what the eBiker expects in every riding situation. To achieve this, we constantly test and optimise and incorporate input from all areas of the bike world, be it from racers, trial riders, professionals or end customers, until we achieve the perfect result.

>>HERE is the detailed test of the Performance Line CX 2025!

The new Bosch Performance CX is rattle-free

The new Performance CX no longer rattles. How did you achieve this?

Mechanical noises can occur with mid-drive motors in certain riding situations, especially with E-MTB fullys. This happens when the external drivetrain (chain, chainring, cassette) starts to vibrate due to root passages or rock gardens, which stimulates the internal gearing. We have minimised this "rattling" as far as possible on the new CX: Thanks to a technical solution, we have succeeded in decoupling the external drivetrain from the drive unit during rolling passages. The result is a drive unit that remains quiet even in the most demanding downhill sections.

Why was it so difficult to get the engine "rattle-free"?

Seemingly small matters are sometimes not easy to solve. A drive unit is a highly complex construction in which mechanics, hardware and software must harmonise perfectly with each other. Added to this are the countless different types of bicycles in which a drive unit is installed. However, our aim was not only to minimise the "rattling", but also to raise the riding experience of the new CX to a new level. The interaction between mechanics and software had to be fine-tuned down to the last detail. To achieve this, we test our solutions in the toughest and most technically demanding riding situations with professional riders. It takes a while before everyone is satisfied, but the result makes us incredibly proud: the best E-MTB experience uphill and quietly downhill.

You are keeping the new freewheel a secret. How does the system differ from conventional solutions?

We want to keep a little secret about our new CX.

>> An overview of the E-MTBs with the new Bosch Performance CX can be found HERE!

We can imagine: We will probably also see the patented freewheel in other Bosch motors in the future. Can we already look forward to a quiet Performance SX light motor?

The Performance Line SX is already very quiet thanks to its innovative engine and transmission concept. It was only launched last year, so it is too early to talk about a new SX at the moment.

>> Click HERE to test the Bosch Performance SX!

The new CX engine has made minimal progress in terms of weight and installation space. Is there not more to be gained here? Other manufacturers offer more watts per kilo.

The "watts per kilogramme" figure looks impressive on paper, but it is by no means everything. We attach great importance to the mechanical durability of our products and make no compromises here. The interplay between the weight of our drive unit and the performance data enables the best balance of mechanical durability, thermal stability, range and wear of drive components. This leads to the characteristic Bosch riding performance, which has been further perfected in the new CX.

Batteries have become lighter. But even here, some competitors deliver more energy for their weight. Why is that?

Our focus is on safety and durability. Thanks to our safety measures, this can mean a minimal increase in the weight of the batteries.

Are the new batteries compatible with "older" Bosch bikes, e.g. with Powertube 750?

Most batteries are compatible, but in some cases it will not be possible to install the new batteries in older models due to the new form factor.

Many e-bikers miss the Fast Charger in the smart system, which Bosch used to have in its programme. Will a faster charger return with the new generation of the CX?

We are currently working with other well-known manufacturers in the Charge2Bike consortium on a standardised charging solution for e-bikes from different manufacturers. The Charge2Bike adapter will enable fast charging of our smart system batteries.