Bosch tuning
Bosch Tuning: The ultimate guide for more speed and freedom on your e-bike
Welcome to our comprehensive guide on Bosch e-bike tuningIf you want to get the most out of your e-bike drive, you've come to the right place. On this page, you'll learn everything about the different Bosch motors, available tuning methods, which products are suitable for which drive – and what legal considerations you need to be aware of.
Why Bosch Tuning?
Bosch drives are among the most popular e-bike systems worldwide. But whether you have a bike with Active Line, Performance Line or CX engine – the standard top speed is 25 km/h. Tuning eliminates this limit and unlocks the full power of your engine. Whether you're looking for sporty riding, steep climbs, or simply more speed on your commute – with the right tuning, you can legally make full use of your bike on private property or abroad.
Important: General Guide, All filters at a glance, Solutions in comparison
Bosch engines at a glance
| Generation | designation | System | Features |
|---|---|---|---|
| Gen1 | classic+ | BES1 | Older engines, simple technology |
| Gen2 | Active / Performance Line (until approx. 2016) | BES2 | First system change, widespread |
| Gen3 | Active Line Plus / Performance Line (from 2018) | BES2 | Compact, quieter, modern displays |
| Gen4 (BES2) | Performance Line CX (from 2020) | BES2 | Smart eMTB tuning, often with chainring protection |
| Gen4 (BES3) | Performance CX Smart System from 2022 | BES3 | New connector type, OTA updates, new diagnostic function |
| Gen5 | Bosch Smart System from 2024 | BES3 | Fully connected with eBike Flow App |
| Rim magnet | e.g. Trek, Cube | BES3 | No sensor arm, magnet sits on the valve |
Bosch tuning by engine in detail
Bosch Gen1 (Classic+ BES1)
The first Bosch drive: robust, loud, but still in use today on many early e-mountain bikes. Anyone who owns an older e-bike will find the EBT Unlock Key The simplest solution for unlocking – without any technical intervention. Ideal for beginners. Read more about Bosch Gen1 in the blog
Bosch Gen2 (Active/Performance BES2)
The second generation brought noticeably more performance and spread rapidly. Control can be achieved via software (EBT) or with chips such as RedPed or MTT. These engines are particularly tuning-friendly. Read more about Bosch Gen2 in the blog
Bosch Gen3 (Active Line Plus BES2)
Bosch Gen3 is whisper-quiet, efficient, and installed in modern e-mountain bikes. The system remains BES2, but is more easily combined with modern displays. Ideal for software-supported tuning via USB or app chips. Read more about Bosch Gen3 in the blog
Bosch Gen4 (Performance Line CX BES2)
The CX motor is the darling of the e-MTB scene. It has been used in many premium bikes since 2020. With torque of up to 85 Nm, tuning makes particularly good sense. EBT Unlock Key or RedPed 3 are the means of choice. Read more about Bosch Gen4 in the blog
Bosch Gen4 Smart System (BES3)
Since 2022, Bosch has been supplying the Smart System (BES3) a completely new architecture. New displays, new connectors, new app. Classic software tuning is not yet possible here – Splug-Dongles currently offer the only practical solution. More about Bosch Smart System (Gen4 BES3) read in the blog
Bosch Gen5 (Smart System from 2024 & BES3)
The further development of the BES3 system: Even more networked, even more restrictive. Bosch is actively fighting against tuning. Anyone who still wants to unlock their car can use the RedPed or Splug back – an external dongle with plug-and-play function. Read more about Bosch Gen5 in the blog
Bosch rim magnet systems
A special feature: Instead of a spoke magnet, Bosch uses a magnet on the rim valve on newer models (e.g., Trek, Cube). This makes traditional boxes no longer work. Currently, only sensor tricks or specialized products like RimBoost are successful. Read more about the Bosch rim magnet system in the blog
Difference between Bosch Gen4 (BES2) and Gen4 Smart System (BES3)
The Bosch Gen4 motors exist in two different system variants that appear similar on the outside but are technically fundamentally different: the classic BES2 system and the new BES3 Smart System. This difference is crucial for e-bike tuning.
Bosch Gen2 - Gen4 – BES2
- Uses the BES2 system (since 2014)
- Round 4-pin charging socket
- Compatible with classic Bosch displays (Purion, Intuvia, Kiox 1, Nyon 1)
- Widely used, many tuning solutions available: Unlock here!
- Not with that Smart System Compatible
Bosch Gen4 - Gen5 – BES3 (Smart System)
- Since 2022 with the Smart System eingeführt
- New 2-pin charging socket (oval, magnetic)
- Only compatible with Kiox 300 / Kiox 500 / LED Remote
- Connection via Bosch Flow App required
- Significantly more restrictive when it comes to tuning – only special solutions such as RedPed function (other solutions)
- Watch out: Bosch rim magnet
Conclusion: BES2 or BES3?
The visual differences are mainly in the charging and diagnostic socket. BES2 uses the familiar round connector, while BES3 (Smart System) uses a new, oval interface. The world also diverges in terms of software architecture: While BES2 continues to offer a wide range of tuning options, the BES3 system is technically encrypted – this requires precise, smart software tuning.
Tuning methods in comparison
Permanently installed
| Method | Description | Advantages | Disadvantages |
|---|---|---|---|
| Chip with app (e.g. RedPed 3) | Combines hardware and app control | Individually adjustable, extensive functions. The RedPed Chip is the only one that can be updated via app | Permanently installed |
| Software tuning (e.g. EBT Unlock Key) | Browser-based activation via USB cable | No installation, resettable | Only for Gen1–Gen4 (BES1 & BES2) |
| Chip tuning (e.g. MTT SmartChip) | Permanently installed tuning chip in the engine area | Permanent activation, usually with activation and deactivation options | Permanently installed |
| Dongle (e.g. Splug) | Intermediate cable, usually for BES3 | Hardware and software can be easily removed and then no longer on the bike. | Partially visible |
| Box (e.g. Badass Box) | Attachable box on the sensor | Easy installation (plug in and move the magnet), no intervention in the engine | Visible |
| Sensor tuning (MTT Smart Sensor) | Replacement or manipulation of the sensor | Invisible, because the sensor is replaced | Long installation |
Which tuning for which Bosch engine?
| Bosch engine | Best Bosch tuning | Note |
|---|---|---|
| Gen1 (BES1) | EBT Unlock Key | Easy and secure via computer & USB cable |
| Gen2 (BES2) | RedPed, EBT Unlock Key | Versatile selection, technically open |
| Gen3 (BES2) | RedPed, EBT Unlock Key | Compatible with more modern displays |
| Gen4 (BES2) | RedPed, EBT Unlock Key | Excellent Performance for eMTB style |
| Gen4 (BES3) | RedPed 3, Splug | Chip with app or smart dongle |
| Gen5 (BES3) | RedPed 3, Splug | Chip with app or smart dongle |
| Rim magnet | RimBoost, Basdass Box 5 | Only BDU37 and BDU 38 engines |
Get started now
Want to get started right away? Then you'll find the right solutions for your engine here:
