More and more e-bikers can be seen on city streets. Until now, making the switch from an old bicycle to an electric bicycle seemed inevitable. But since Pendix, a start-up from Zwickau, has developed a retrofittable electric motor for bicycles, this is no longer necessary. The well-loved bicycle can easily be converted. Christian Hennig, technical director at Pendix, explains why the company initially chose a completely different path and why it ended up on the e-bike market.

Why did you start Pendix?

We are five founders and got to know each other during our studies in Zwickau. During this time, we were mainly involved with electric car rides and we also took part in the Formula Student design competition. As a spin-off from the university, we decided to set up something of our own together in Zwickau and started to develop and manufacture innovative propulsion and automative electronics.

How did you come up with e-bikes?

That was quite simple. We received an inquiry from the bicycle industry. When we took a closer look at the market, we realised that this segment of the industry is a good workfield for us. While for many years the automobile sector has been characterised by a high degree of professionalisation, the bicycle industry is still very much in its initial stages. As a result, we were able to successfully develop as a new company. We soon realized that with our experience, we could contribute to the bicycle market.


E-bikes for the fire brigade? With the retrofittable drive this is not a problem – and there is even room for the fire hose. ©Pendix

Wasn’t that a big change?

Yes, because we first developed a bicycle propulsion system with a gearbox on the electrical motor for cargo bikes. However, the project ground to a halt on the customer’s side. This gave us the idea of developing a propulsion system for bicycles which could be retrofitted. That was about six years ago.

How did you finance yourself during this time?

Through a start-up scholarship, as we were still at the university. Then we financed ourselves by providing various services and finally founded Pendix GmbH in 2013. Shortly afterwards, we started looking for investors and subsequently found what we were looking for. It took us about two years to get our bicycle propulsion system ready for mass production. We finally presented our propulsion system at the Eurobike in Friedrichshafen, one of the largest bicycle fairs of all.

Motor für e-Bike von Pendix

Clearly visible – the coils in the drive ©Pendix

How does the propulsion system work and how can it be installed?

It was important to us during development to make the propulsion system as simple as possible. Both in terms of installation and use. Therefore, every bicycle that is to be retrofitted only needs to fulfil one main criteria. It must be equipped with a BSA bottom bracket. This is the case for about 85 to 90 percent of all bicycles. It is also important that the battery fits into the frame and that the motor can be mounted on the left side. It is very easy to use – just install the battery, switch it on and you can start cycling. The force exerted by the cyclist while pedalling is measured in the crankshaft and recorded by the motor control unit, so that the motor knows how much power it has to generate.

So what do I do if I want to retrofit my bike?

In the meantime, we have built up a network of over 800 specialist dealers in Germany. We are also represented here by a wholesaler who sells our bicycle solution. In addition to our dealer network, where you can buy the propulsion systems, we started our own online shop this year. There I can choose whether to have it sent to my nearest dealer for installation or directly to me for a do-it-yourself installation. The crankshaft must be switched, battery, motor and speed sensor must all be integrated. Of course, the bike should be checked before the conversion to see if it is technically safe and roadworthy.

What difficulties did you have to overcome when founding Pendix?

Getting a start-up scholarship was a big obstacle. We had to improve our concept twice until it worked. The founders in Germany are very busy with formal things. You have to go through with it. If you have a good idea that you are convinced of, don’t let yourself be discouraged too quickly, but fight for it.

Antrieb und Flaschenakku von Pendix

You don’t need anything more to convert your favourite bike – drive and battery bottle ©Pendix

Was there a moment when you wanted to give up?

Generally, giving up was never an option, but yes, of course there are moments of doubt. Because even in a start-up, it is not always peaches and cream. We had our arguments. It can often be the case that the next goal is the big milestone. This can lead to losing the overview when you’re standing in front of a huge pile of work. Here, it often helps to set smaller partial goals and to reach them bit by bit until you’ve finally climbed that big mountain. An especially difficult phase was making the prototypeready for production. It is a great challenge and achievement ensuring that every product comes off the production line right away. Looking back, we have mastered this very well, despite the great challenges.

What does it mean to run a company?

You have to grow a little into the development of the company. We now have 40 employees. What used to work via commendations is now different. At a certain point, the processes become unclear and inefficient. Then the areas have to be divided up and regular meetings need to be held. They have to work actively on the processes and still be able to make dynamic adjustments at short notice. A young company is very fast-moving, so new insights can also change a previously decided direction, which you then have to react quickly to.

What has been your biggest success with Pendix so far?

The market launch was clearly a major milestone. Most of the time you are never 100 percent satisfied with your own product and would like to continue working on it forever. Developers sometimes want to invent the golden key to success. But the best product is of no use if it is not launched on the market.


Well hidden – the battery looks like a drink bottle ©Pendix

How did you bring your product to the market?

We did a lot of marketing, from trade shows to online marketing to advertisements in trade magazines and much more. In order to access the market as quickly and efficiently as possible, we engaged a marketing agency as a service provider and at the same time, set up the sales team. The sales staff successively took over from specialist dealers, as well as customers in other channels, such as bicycle manufacturers or fleet operators. After initially working on consumer-end marketing without direct sales, we then focused primarily on retailer marketing in order to bring the propulsion systems to the market via this channel. We learned relatively quickly how to support retailers with POS materials and other means. There is also a lucrative bonus program for retailers.

What is the next step?

We are currently working on various product updates, which we plan to showcase at this year’s Eurobike, as well as on the expansion of our Pro App. It has been available for Android and Apple since last year. In addition, we are currently investigating the potential of the Australian market for possible expansion. In Europe, we are already selling the e-drive in ten countries.



If you want to know more about e-bikes:

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Anti lock braking system for pedelecs and e-bikes