You can retrofit an e-bike from 250 euros. We show which motors from Bafang, Pendix, iMortor and Bikight are worthwhile.
If you have a bike you love at home, you don’t have to spend a lot on an e-bike. With high-quality sets for retrofitting, an old bike can be quickly and legally turned into a fully-fledged e-bike or pedelec.
In the past few months we have tested a total of five retrofit kits for e-bikes. Everything for front, middle and rear engines is included here. The following kits compete in our leaderboard:
- Center motor Bafang BBS-01B (test report)
- Central motor Bafang MM G340 (test report)
- Mid -motor Pendix Edrive 300 (test report)
- Front engine iMortor 2.0 (test report)
- Rear engine Bikight SW900 (test report)
The kits we tested mostly correspond to the most well-known products on the market. We will be testing more retrofit kits and updating the list over the coming weeks and months. There are a few more kits that we will be testing. For example, the retrofit kits from Yose Power, which can be found on Amazon , among other places.
If you are looking for cheaper alternatives without tinkering, you will find an overview in our list of the best e-mountain bikes up to 1600 euros .
How much does a retrofit kit for e-bikes cost?
Retrofit kit prices vary widely. You can often get them from dealers with a German location for 100 to 200 euros more than from a Chinese online shop. Banggood carries most retrofit kits; also at the best prices usually. The exception here is Pendix. The prices are permanently the same (high) and the sale takes place exclusively directly via Pendix.
Are retrofit kits for e-bikes legal?
In the legal or illegal guide, we clarify which requirements pedelecs have to meet in order to be allowed to drive legally on German roads . Everything about e-bikes and pedelecs . In principle, you can retrofit your own bike, according to a joint interview with Deutschlandfunk, ADFC (Allgemeiner Deutscher Fahrradclub eV) and TechStage ( from minute 20 ). This is also confirmed by Dr. Arun Kapoor, lawyer for product liability and product safety law at the law firm Noerr LLP, in an interview with Emobiljournal . According to Thomas Geisler from the press service bicycle , the retrofit sets do not even have to have a CE mark. In case of doubt, the distributor, i.e. online shops like Amazon, is liable.
Many retrofit kits also offer a throttle. It is better not to attach it, as such a lever is not yet permitted in public transport on German roads. The motor may accelerate to a maximum of 6 km/h without pedal assistance; this is considered a pushing aid in Germany. In general, a pedelec, i.e. an electric bicycle without an insurance license plate, is not allowed to do more than 25 km/h with motor support. The rated power of the motor must not exceed 250 watts.
The bike to be retrofitted should also be in perfect condition. The ADFC and the Institute for Bicycle Technology and Safety advise against conversion ( ADFC statement ) because the components of conventional bikes are not designed for additional loads. according to dr Kapoor, on the other hand, would not be able to attribute any accidents to technical failures of converted bicycles. Accordingly, one can only state: The bike to be retrofitted should be in perfect condition. The material should not show any signs of fatigue. Ideally, it is best to upgrade a new or young bike. If you are unsure, you should go to a specialist dealer. Providers of retrofit kits such as Pendix have a list of partner dealers on their own website.
How to assemble e-bike kits?
If you order a retrofit kit online, you have to install it yourself, with a few exceptions. This is usually not difficult and usually only requires time and tools. Above all, a bottom bracket wrench is a must for mid-engine sets; you can get it at Amazon for around 14 euros . The products usually come with assembly instructions. There are also various assembly instructions for the models tested here on YouTube.
Cranks, motor, brake lever and control unit – these are usually the components of a retrofit kit.
If you don’t have the time or patience to convert your bike yourself, go to Pendix. Here you can carry out the assembly via a specialist dealer. Of course, that costs extra.
1st place: Bafang BBS-01B
With coupon code BG04aa52 , the Bafang mid-engine is currently available from Banggood for 520 euros . It is well made and legal in Germany with 250 watts of power. According to various forum entries, the engine reaches 80 Nm; this gives the user a relaxed ride on hills and smaller mountains.
In addition to the mid-engine, Bafang supplies new cranks, a large color LCD on-board computer, a hand controller, a speed sensor, new brake levers, a front light and countless cable ties. Assembly tools and instructions are also included. You only have to buy an inner bearing key yourself. We ordered ours from Amazon for around 14 euros .
Bafang BBS-01B in the photo gallery
For the Bafang BBS-01B (test report) you need a battery. Here we opted for the Haniwinner H194 including a European power supply for just under 270 euros . The price can currently be achieved with the coupon code BG2eb379 at Banggood. The capacity of the battery is 561 Wh. In practice, you can get between 30 and 70 kilometers with it; depends on many factors such as support level and condition of the route.
2nd place: Pendix Edrive 300
Pendix is premium and you can tell by the price. The Pendix Edrive 300 we tested (test report) costs 1500 euros in a set including the battery with the voucher code HeiseMedien2022 . On the other hand, the system is absolutely silent, is hardly noticeable and there are no annoying cables, but also no separate display. The Pendix kit has a three-year guarantee (upon registration) and is of high quality.
3rd place: Bikight SW900
The rear motor Bikight SW900 (test report) with 1000 watts is available from Banggood for 300 euros . With voucher code BG690f26 it only costs 279 euros – a real bargain. Unfortunately, the version is illegal in this country. The 250 watt model is currently sold out. For the compatible battery Haniwinner HA194 561Wh you put 210 euros on the table with code BG6e013a . In total, you pay around 460 euros for the entire set. No other kit in our list of the best is so cheap.
4th place: Bafang MM G340
Actually, the Bafang MM G340 kit (test report) is in no way inferior to our first-placed Bafang BBS-01B. On the contrary, the MM G340 is a very powerful mid-engine that is a pleasure to drive across the board. Unfortunately, the motor has an output of 750 watts; this is illegal in Germany. It’s a shame, because otherwise this powerful mid-engine would have won first place.
5th place: iMortor 2.0
Actually, the iMortor 2.0 (test report) is a great idea. The battery, electronics and motor are all in the front wheel. All you have to do is run a cable to the handlebar and connect it to the included controller. We need a total of 15 minutes for the conversion.
There is no shortage of tools and parts with the iMortor.
iMortor in detail
That sounds too good to be true and unfortunately it is. Because the iMortor 2.0 has a range of around 10 to 15 kilometers, you need an app to be able to use it at all, and you can’t use it without a throttle. This makes the model illegal in Germany and simply unusable in general. The product is still listed via Banggood , but is no longer available. On you can find the successor, the iMortor 3.0, for around 420 euros.
Conclusion
Retrofit kits transform an existing bicycle into a fully-fledged e-bike or pedelec for little money. If you bring some time with you, you can save several hundred euros on cheap e-bikes from discounters.
If you are looking for cheaper alternatives without tinkering, you will find an overview in our list of the best e-mountain bikes up to 1600 euros .
