Unlock the speed limit of your electric bike with a Bafang badassBox tuning box. The badassBox is the easier ebike tuning to install and remove. No wiring or engine cover removal required - just slide the badassBox over the speed sensor and you are ready to go! Unleash the full speed of your ebike engine and you are ready to ride as fast as you can!
Tested on BAFANG M500 and M800
Our newest and best e-bike tuning for Bafang mid-mounted drives. New streamlined casing with patented snap-lock fastening for even faster mounting and release. Even more robust thanks to a special potting compound from the automotive industry. New electronics for even greater range with a single AAA battery. A quality product designed and manufactured in Germany.
SCOPE OF DELIVERY                                                                                                               
badassBox 4 Bafang with AAA battery and spoke magnet with thumb screw. 
The badassBox 4 is the result of more than a year's development. We have completely re-designed the casing, made it more streamline and replaced the o-ring of the previous version with our patented snap-lock fastening. Making it more streamline makes it even easier to fit. The new snap-lock fastening means you can attach and remove your badassBox with just one hand in seconds. At customer's request, we have additionally added an optional securing feature on the snap lock using a cable tie.
The CR2 battery has been replaced with a AAA battery, so you can pick up replacement batteries much cheaper on just about any street corner. Tool-free battery change can be carried out quickly and easily while you're on the road – but should only be necessary once a year, or every 7000km. This was made possible by our in-house developed and patented field amplification technology FEET (Field Enhancement & Elimination Technology). To protect against moisture and mechanical stress, the electronics are glued into the casing and completely sealed with a special casting compound.
The badassBox is developed and manufactured exclusively by us in-house. Before and after casting we check each badassBox individually. Customer satisfaction and quality are our top priorities. If you have any questions, don't hesitate to ask – we'll get back to you with an answer straightaway, mostly on the same working day. Due to the high quality and our focus on customer satisfaction, we additionally offer a 1 month money-back guarantee.
The badassBox is attached to the speed sensor of the e-bike and overrides the 25km/h speed limit. Remove it and your e-bike is restored to its original state.
Contactless e-bike tuning
Streamlined, registered design for casing
Patented snap-lock fastening
Securing feature on the housing
Patented field enhancement technology
AAA battery for range in excess of 7,000km
Auto industry potting compound
Doubled quality control
Made in Germany
One month money-back guarantee
The badassBox Bafang is attached to the chain stay with a cable tie and the speed sensor of the e-bike is unscrewed and placed on the box.

During the initial assembly, the supplied spoke magnet must be fitted instead of the original magnet. Our spoke magnet works in the same way as the original magnet without the badassBox, but is necessary for the function with our patented field reinforcement when the badassBox is attached. After placing the sensor on the badassBox, the spoke magnet must be moved to the edge of the housing in the direction of the snap lock. If the spoke magnet touches the badassBox, the spoke magnet must be placed as close as possible to the badassBox and rotated by 90 °. Finished!

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



The contactless and wireless badassBox transmits a modified 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 in seconds – and just as quickly removed, restoring your e-bike to its former road-legal condition.
For all these advantages, a wrong speed, and values derived from it, are displayed. We recommend the use of GPS-related accessories for a more precise data acquisition of driving data (smartphone, bike computer, etc.).
Dimensions: 61 x 40 x 15 mm.
Weight: badassBox 27g, including battery 37g.
Battery: 1.5V AAA battery (IEC R03).
HOW TO INSTALL the badassBox 4:
For best results, during the installation of the badassBox keep the bike engine TURNED OFF at all times. 
1)  Remove the battery from the badassBox and make sure that it is fully charged. Wait before re-inserting the battery.
2)  Slide the badassBox over the speed sensor and install the magnet on the wheel spoke. Align the magnet as shown below. 
3)  Make sure that the battery was removed from the badassBox for at least 30 seconds before re-inserting into the badassBox.
4) Turn on the system and make a few wheel turns. If the display shows a speed, the device is working. 
On certain e-bikes models it may be advised to relocate the magnet on the rear spoke or to twist it at 90 degree (magnet facing up or down) to allow more tolerance between box and magnet. 
The returned BadassBoxes are tested with a specific badass diagnostic tool for any errors/malfunctions. In the majority of the cases boxes are in good working conditions so please make sure that you have followed the instruction correctly before requesting a new unit.