Main Product Information
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 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
- one CS Adapter
- four cable ties
The pin-shaped CS sensor is located in the area of the dropout.
To get to the sensor you have to remove the rear wheel.
Unscrew the screws of the bracket that secures the sensor to the dropout.
Separate the sensor from the bracket.
Insert the pin-shaped sensor into the adapter so that the flat side of the sensor is aligned with the corresponding recess in the adapter. The sensor must be inserted completely into the adapter, so that only the cable protrudes and the snap closes flush with the surface of the adapter. (In the photo, the sensor is not yet completely inserted).
Attach the adapter to the frame of your bike with the supplied cable ties.
Reinstall the rear wheel.
Slide the badassBox onto the adapter until it clicks into place.
Mount the spoke magnet and align it with the edge of the badassBox housing. That's it. Have fun with your faster e-bike!
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.

The bike feels completely different once derestricted - it's just like a whole different bike! The rides are so much more fun now! Tuning kits are safe to your bike and every ebiker should have one installed! You will love riding your ebike with it - guaranteed!
Matt - Owner of Two Wheels Empire
What Our Clients Say About It?
Chip for my Cube
Item was on pre order and took some time but the guys kept me updated. Arrived and all fitted and now the bike is free. Top item and great sellers
Excellent product
Transformed the bike. Highly recommend.
This is a total game changer
From initial inquiry to order and then delivery, the purchase was seamless. The Speedi is amazing removes the bogging down feeling once your bike reaches it limiter. The Speedi allows you to go as fast as you can pedal or run out of gears. Really easy to fit took approx...read more
Installed on GT eforce Amp+
Installed on GT eforce Amp+ Quick and easy to install. Did not need to go to bike shop and get anything enabled :-) Would be nice if it could display correct spped etc, so that when bike paired as sensor to Garmin, but understand why not...