BadassBox G4 Set - Bosch 2014-2023

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.

If this sensor of your Bosch motor - as shown in the picture below - is integrated in your bike, then the badassBox4 Bosch G4 set is exactly what you need. This sensor is used by Trek.


This set contains everything you need for the assembly of the badassBox 4 for your e-bike from Trek with Bosch mid-mounted motor and integrated G4 Speed Sensor. A quality product designed, engineered and manufactured by us in Germany. The assembly requires a small conversion. Please read the instructions on the left before ordering!

The delivery includes the following parts:
- one badassBox 4 Bosch
- one badassBox 4 housing cover
- one AAA battery
- one spoke magnet with thumb screw
- one G4 Adapter
- a button head screw [M3 x 8 (ISO 7380-2)]
- a pad made of elastic foam
- four cable ties

The integrated Bosch Sensor is located in the area of the dropout. To get to the sensor you have to dismount the rear wheel.



With the included button head screw you can screw (for this you need a 2.5 mm Allen key) the G4 speed sensor to the G4 adapter (1).



(2) A suitably cut pad made of self-adhesive elastic foam is included as an option. This pad can be glued to the G4 adapter to attach it to the chain stay without the risk of scratches.



With the enclosed cable ties (3), you can mount the G4 adapter including screwed G4 speed sensor at a suitable location on the chain stay (4), where it is possible to slide the badassBox over the adapter.



Slide the badassBox onto the adapter until it clicks into place. Reinstall the rear wheel.



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.