BadassBox 4 Brose

The badassBox is attached to the speed sensor of the e-bike and overrides the 16 mph (25 km/h) speed limit - you can expect to reach speeds of up to 25 mph (40km/h) , depending on the bike and gearing. Your displayed speed will be 2 times slower than your real speed. We recommend the use of GPS-related accessories for a more precise data acquisition of driving data (smartphone, bike computer, etc.).

The tuning kit manipulates the speed signal without altering the motor's power relative to pedaling speed. This guarantees a smooth motor control without speed limit interruptions. Depending on a tuning kit, some determine when assistance stops, while others remove the restriction entirely for continuous support. However, the achievable speed mostly depends on the eBike model. Achievable speed can be calculated using a simple formula:

Speed = Cadence [rpm] * Wheel circumference [mm] * Front Chainring Teeth / Rear Chainring Teeth * 60 [min/h] / 1.000.000 [mm/km]

The contactless and wireless badassBox transmits a modified speed signal in order to override the speed limit of your e-bike – without interfering with the motor's electronic circuitry or software. There's no need to open the motor and there is no risk of damaging it, the BadassBox can be fitted or removed in seconds.

This tuning kit is made to fit bicycles with Brose motors; please check the speed sensor type to select the right kit. This kit will fit your bike perfectly if you have pin shape speed sensor:


And you need the BadassBox 4 Brose CS Set if your speed sensor looks like this:




The assembly requires a small conversion. Please read the instructions on the left before ordering! A quality product designed, engineered and manufactured in Germany.

The delivery includes the following parts:
- one badassBox 4 Brose
- one badassBox 4 housing cover
- one AAA battery
- one spoke magnet with thumb screw
- four cable ties

The badassBox 4 Brose is fitted over the Brose speed sensor next to the rear wheel. When the snap-lock clicks into position, the badassBox is fitted securely to the sensor.­ For extra secure fitting, the badassBox can also be fastened with a zip tie.

Once the badassBox has been fitted onto the sensor, the spoke magnet must be offset to the casing edge in the direction of the snap-lock clasp. It's now ready for use.

Following removal of the badassBox, the spoke magnet must be returned to its original position.

Installation Guide

Please note that the operation of this type of modified electric bikes on public roads may be against the law in some countries. The manufacturer takes no responsibility for damages resulting from the use of BadassBox products. Electric bikes equipped with BadassBox products are not allowed to be used on public roads, cycling paths and public places. Electric bikes equipped with BadassBox products can be used exclusively on private property and entirely at one’s own risk. The use of BadassBox products may void the warranty of your ebike.

We strongly recommend using other safety features and protective gear to prevent injuries in higher speeds.

BadassBox products are thoroughly tested and we stand by their quality - Badass Box provides 2 years warranty to all their products.

Warranty does not cover damage resulting from eBike software updates. Remove the tuning kit before updating the software. Check with us first to ensure the kit is compatible with your updated eBike. We cannot guarantee that the kit will function the same after updates. Please exercise caution.