E-Performance: E-bike retrofit solutions are still somewhat overshadowed by the e-bike boom, which seems to be coming to an end. Many bike owners would benefit from a motor retrofit, especially if they recently bought a new bike, have special requirements and preferences, or have a particularly strong emotional connection to their own bike. So why are solutions like the Pendix retrofit not as popular as regular e-bikes? On the one hand, this is due to unjustified prejudices: Retrofit solutions are sometimes denounced as do-it-yourself solutions - in the case of Pendix, however, as a buyer you get a full two-year guarantee after installation - preferably by a specialist dealer - and the system has been tried and tested thousands of times. Certain reservations also play a role for many potential buyers: Will the riding experience of my bike change negatively after the retrofit? How big is the maintenance effort? In a three-part Pendix series of articles, we would like to clear up prejudices and fears of contact. In the first part we present the system, explain which types of bicycles can be retrofitted and for whom the purchase is particularly worthwhile.
The Pendix drive: The key technical data
A mid-engine for retrofitting? That sounds strange at first, because e-bike retrofit kits are often still associated with the well-known hub drive. With the Pendix solution, however, the 250W motor power is located directly where the power should arrive: on the crank. The brushless drive is housed in a round, compact aluminum housing. Since this does not require an internal gear, it does not provide any additional resistance when deactivated: This enables easy pedaling at speeds of over 25km/h or even covering flat stretches with the drive deactivated.
The battery can be easily mounted on the holes for the drinking bottle holder and comes in a 300Wh or 500Wh version. The clever design with a large rotary wheel on the top and bright LEDs also makes a control unit on the handlebars superfluous - less cable clutter and easy installation. Of course, the battery is completely waterproof and the drive can also be used in the most adverse conditions.
On paper, the motor delivers a respectable 50Nm: Although it cannot quite keep up with the most powerful mid-mounted motors, it is at the level of well-known city and trekking drives and should be more than sufficient for most areas of application.
For whom is a Pendix retrofit worthwhile?
I own a high-quality bike without a motor, but would like to switch to an e-bike
Not so long ago, a high-quality bicycle without a motor was purchased. However, for a variety of reasons, the requirements have now changed. For commuters, this can mean a longer commute, health conditions can play a role, or the "want-to-have factor" of an e-bike is simply too great. But what about the old, new bike? In the fiercely competitive second-hand market, the sale usually hurts quite a bit financially.
I have special requirements for my bike
Not every cyclist will be happy with standard bikes. This applies to particularly tall and/or heavy people as well as drivers of special cargo bikes, for example. Here, the search for a suitable bike often resembles an almost endless odyssey through the bike shops of the republic. Once you have finally found a suitable base, it should of course remain as long as possible, after all, a new purchase is likely to be complicated again.
I don't want to part with my "non-e-bike".
Last but not least, a somewhat romantic argument: For many cyclists out there, the bike is more than just a commodity and over time you learn to love your everyday companion. Of course, the separation is all the more difficult, especially if the bike is still in good technical condition.
Which bikes can be retrofitted with the Pendix motor?
A huge advantage of the Pendix drive is its easy assembly and the high level of compatibility with almost all common bicycles and bicycle frames. The basic requirement is a BSA bottom bracket thread with a width of 68 or 73mm. The fact that frames with Pressift bottom brackets are not supported is not too important; After all, this type of bottom bracket assembly is mainly found in racing bikes or extremely light mountain bikes - but since the Pendix drive is designed more for city bikes and commuters, the overlap should be extremely small. Threads for a bottle holder are ideal for attaching the battery; even if these are not available, the energy storage device can be mounted using clamps.
Here are the detailed requirements for the retrofit. If you have any questions, either Pendix Support or the specialist dealer will help.
What are the advantages of the Pendix drive?
We have already mentioned some of the advantages of the Pendix drive: The simple installation without structural changes to the frame, the direct power transmission through the central motor and the non-existent resistance if the drive does not help the driver. What has not been mentioned so far is the almost sensationally low weight: The "smallest" version with a 300Wh battery weighs only 6,5kg for the entire system - this means that many modern bikes remain below the 20kg mark even after the motorisation. The variant with a large 500Wh battery is only 400g heavier. In many cases, the total weight of a bike retrofitted with Pendix is less than that of conventional e-bikes.
In addition, the design of the drive manages to bring together two major advantages of the center and hub motor: The brushless motor is almost inaudibly quiet during operation - like many hub motors - but delivers its power directly to the drive train - like a conventional center motor.
What are the next steps?
In the next part of the story we will introduce our retrofit bike. We will then have this equipped with the drive at a Pendix specialist dealer in order to then add a detailed driving report in the final part.