bafang ebike repair shop workers

Bafang Motor Problems: The Worst 5 Issues & How To Solve Them

The increasing popularity of e-bikes has fueled innovation in electric motor technology, with Bafang at the forefront. Even with advanced tech, occasional issues can arise. This guide addresses common Bafang motor problems and offers practical solutions for troubleshooting and maintenance, ensuring your e-bike rides remain smooth and enjoyable.

Bafang BBS Mid-Drive Problems: Troubleshooting Common Issues

While Bafang mid-drive motors are generally reliable and offer a powerful boost to your cycling experience, it’s important to be aware of a few potential issues that may arise with specific models. Understanding these challenges can help you diagnose and address them.

bafang mid drive system bbs01b bbs02b bbshd

  • Bafang BBS01B (250/350W): This lighter-duty motor, while perfect for city commuting, may occasionally struggle with low torque output on steep hills, but its compact size makes for a discreet and lightweight addition to your bike. If you experience this, ensure you’re in the correct gear and consider updating the firmware for improved performance.
  • Bafang BBS02B (500/750W): While versatile, the BBS02B might overheat during prolonged climbs, particularly when used at higher power settings. If this happens, check the temperature sensor first. If the issue persists, it’s recommended to seek professional assistance. Regular maintenance and proper gear selection can help prevent overheating.
  • Bafang BBSHD (1000W): As the powerhouse of the Bafang lineup, the BBSHD’s high power output can sometimes lead to increased battery drain. Its robust construction and high torque make it the ultimate e-bike motor for extreme riders and heavy loads. Monitoring your battery’s state of health and potentially upgrading to a more robust battery management system (BMS) can help mitigate this issue.

Bafang M-Series Mid-Drive Motor Issues

bafang m510 motor

The M-series of Bafang motors, encompassing models such as the Bafang M200, M300, M400, M420, M500, M510, M600, M625, M800, and M820, is celebrated for its integration of advanced features and smart technology. However, these motors are not without their unique challenges. Users have commonly reported issues like sensor inaccuracies, software glitches, overheating, and excessive noise. To address these problems, it’s crucial to keep your firmware up-to-date and to regularly inspect sensors and connections for optimal performance.

  • Sensor Inaccuracies: Torque sensors, in particular, can sometimes provide inconsistent readings, leading to erratic or unpredictable assistance levels.
  • Software Glitches: The motor’s firmware, while generally reliable, can occasionally experience bugs or glitches that affect performance.
  • Overheating: Under heavy loads or prolonged use, the motor may overheat, potentially triggering a safety shutdown.
  • Noise: Some users have reported excessive noise or vibration from the motor, especially during acceleration or under load.

To address these issues:

  • Keep firmware updated: Regularly check for and install the latest firmware updates from Bafang to ensure optimal performance and address any known bugs.
  • Regular inspection: Periodically inspect the motor, sensors, and connections for any signs of damage, wear, or loose connections.
  • Avoid overheating: Monitor the motor’s temperature during use, especially in hot weather or during strenuous riding. Take breaks if the motor feels excessively hot.
  • Proper maintenance: Follow the manufacturer’s maintenance recommendations for lubrication and cleaning to ensure smooth operation and prevent premature wear.
Bafang Model Common issues Troubleshooting Tips
BBS01/BBS01B Low torque on hills Use correct gear ratio; Update firmware
BBS02/BBS02B Overheating Check temperature sensor; Consult a technician
BBSHD/BBS03 High battery drain Monitor battery; Upgrade to robust BMS
M200 Limited range Battery cells, BMS
M300 Sensor inaccuracies Sensor calibration
M400 Inconsistent sensor performance, Noisy Sensor calibration, check for loose components
M420 Inadequate torque Torque sensor, gear ratio
M500 Excessive noise Check for loose components, gear alignment
M510 Software glitches Firmware update, reset settings
M600 Overheating, Power surges Temperature sensor, software update
M625 Unresponsive throttle Throttle sensor, software update
M800 Limited top speed Gear ratio, speed sensor alignment
M820 Voltage issues Check battery voltage, BMS

Battery-Related Issues: Keeping Your Bafang Motor Powered

e bike battery conversion kit issues

Your Bafang motor’s performance is directly linked to its battery’s health and functionality. Several battery-related problems can arise, affecting your e-bike’s range, power delivery, and overall reliability.

  • Insufficient Voltage: If your battery isn’t fully charged or is unable to supply the correct voltage to the motor, you might experience reduced power, sluggish acceleration, or even complete motor shutdown. Always ensure your battery is fully charged and in good working condition. If the voltage remains low, consider replacing the battery or consulting a professional for further diagnosis.
  • Faulty Cells: Damaged or faulty cells within the battery pack can significantly reduce its capacity and overall performance. If you suspect faulty cells, it’s crucial to have the battery inspected and repaired by a qualified technician. In some cases, replacing individual cells might be possible, but in others, a new battery may be necessary.
  • Battery Management System (BMS) Malfunctions: The BMS is the brain of your battery, regulating charging, discharging, and overall health. A malfunctioning BMS can cause a variety of issues, from improper charging to unexpected shutdowns. If you suspect a BMS problem, it’s best to consult a professional to avoid further damage to your battery or e-bike system.

Controller & Sensor Troubles: A Smooth Ride’s Unsung Heroes

Beyond the motor itself, the controller and various sensors play a pivotal role in your Bafang motor’s operation. Issues with these components can lead to performance hiccups and an inconsistent riding experience.

  • Temperature Sensor: Overheating can damage the motor, so if your e-bike unexpectedly shuts down or performs erratically, it’s worth checking the temperature sensor. Remove the motor cover and look for any signs of overheating or damage to the sensor. If necessary, replace the sensor to ensure safe operation.
  • Torque or Cadence Sensor (Mid-Drive Motors): Bafang mid-drive motors utilize either a torque or cadence sensor to detect pedal input. Malfunctions in the torque sensor can result in an uneven or jerky feel during pedal assist. Inspect the sensor for visible damage or debris that could hinder its functionality. In some cases, recalibrating the sensor might be necessary. Alternatively, if your motor uses a cadence sensor, inconsistent or delayed motor assistance could signal a problem. Check the sensor and its wiring for any damage. Should the issue continue, seeking professional help is recommended.
  • Speed Sensor and Magnet: The speed sensor relies on a magnet placed on the wheel’s spoke to measure speed accurately. If your speedometer is inaccurate or the motor behaves erratically, check the magnet’s position and ensure it’s securely attached. The magnet should be aligned with the sensor and have a clearance of approximately 1-3mm.
  • Controller: The controller interprets sensor input and manages power delivery to the motor. Issues can cause erratic behavior such as sudden acceleration or power loss. If you suspect a controller problem, consult a technician familiar with Bafang motors for diagnosis and repair.

Cable & Connection Issues: Ensuring a Seamless Flow of Power

connecting bafang e bike conversion kit

The intricate network of cables and connectors in your Bafang e-bike system is essential for seamless communication and power delivery between components. However, loose or damaged connections can disrupt this flow, leading to frustrating performance issues.

  • Motor Cable Inspection: The motor cable, exposed to the elements and constant movement, is susceptible to wear and tear. Regularly inspect the cable for any signs of fraying, cuts, or exposed wires. If you notice any damage, replacing the cable is crucial to prevent further electrical problems and ensure safe operation.
  • E-Brake and Gear Sensor Connections: Loose or faulty connections to the e-brakes and gear sensors can cause erratic motor behavior or unexpected shutdowns. Double-check these connections to ensure they are firmly plugged in and free from corrosion or damage.
  • Anderson Power Pole Connectors: These connectors link the battery to the controller, providing the essential power supply for your motor. It’s paramount to ensure they are correctly installed and tightly connected. A loose or improperly installed Anderson connector can disrupt power delivery, leading to intermittent power loss or complete motor failure.

LCD Display & Error Codes: Deciphering Your Bafang Motor’s Messages

bafang LCD display error code

Your Bafang motor’s LCD display is a valuable tool for monitoring its performance and health. Occasionally, it might display error codes, indicating specific issues that require attention.

  • Error 30 (Communication Error): This code suggests a communication problem between the LCD display and the controller. Check the connections between these components for any looseness or damage. Sometimes, simply unplugging and reconnecting the cables can resolve the issue.
  • Error 21 (Speed Sensor Error): If you see this code, it’s likely an issue with the speed sensor or its magnet. As mentioned earlier, ensure the magnet is properly aligned with the sensor and securely attached to the spoke. If the problem persists, the sensor might need to be replaced.
  • Error 12 (Controller/CPU Error): This code signifies a more serious problem with the motor’s controller or central processing unit (CPU). In this case, seeking professional assistance from a qualified technician is recommended.

Gear Ratio & Chainring Size: Optimizing Your Bafang Motor’s Performance

Bafang motors are renowned for their adaptability to various gear ratios and chainring sizes. However, choosing the right combination is essential for maximizing your motor’s efficiency and performance.

  • Gear Ratio: The gear ratio determines the relationship between the motor’s speed and the speed of your bike’s wheels. Experiment with different gear combinations to find the optimal balance of power and efficiency for your riding style and terrain. A lower gear ratio provides more torque for climbing hills, while a higher gear ratio offers greater top speed.
  • Chainring Size: The size of your chainring also affects your motor’s performance. A larger chainring will give you more top-end speed but may sacrifice some hill-climbing ability. Conversely, a smaller chainring will provide better acceleration and hill-climbing power at the expense of top speed. Consider your typical riding conditions and preferences when selecting a chainring size.

Maintaining Your Bafang Conversion Kit: Keeping Your E-Bike Running Smoothly

Regular maintenance is key to maximizing the lifespan and performance of your Bafang motor. By following these simple tips, you can ensure your e-bike continues to deliver a reliable and enjoyable ride.

  • Keep It Clean: Regularly clean your motor and its components to remove dirt, debris, and grime. This will prevent buildup that can lead to premature wear and tear.
  • Check Connections: Ensure all electrical connections are secure and free of corrosion. Loose or damaged connections can disrupt power delivery and cause performance issues.
  • Stay Up-to-Date: Keep your motor’s firmware updated to ensure you have the latest features and bug fixes. Check the Bafang website or your e-bike manufacturer’s website for available updates.

By dedicating a little time to routine maintenance, you can enjoy a trouble-free e-biking experience and keep your Bafang motor running at its best for years to come.

8 thoughts on “Bafang Motor Problems: The Worst 5 Issues & How To Solve Them”

  1. Bonjour,

    En Mars 2023, j’ai acheté un Velo fantic Issimo Fun moteur bafang m500 mm(G250.250.C.15 033F5TB250001)d’occasion à un loueur de vélo (Go Bike 17 Ile de Ré). Celui-ci à dû changer le moteur d’origine (l’ancien étant HS). Hors, nous nous sommes aperçus dernièrement que la lumière arrière ne fonctionnait pas. Nous l’avons testé et le contrôleur délivre 3.4V au lieu de 5.8V.
    5.8V étant apparemment le bon voltage puisque ma femme possédè elle aussi un vélo Fantic mais avec un moteur d’origine. D’autre part, dés que la lumière avant se met en marche, la capacité de la batterie chute.
    D’après le revendeur, le problème viendrait certainement du software qui ne serait pas le bon. Malheureusement, celui-ci ne le possède pas. Nous recherchons donc le fichier CRX10NC3617i142040.6 pour remettre mon vélo à son état d’origine.
    Auriez-vous ce fichier ? ou connaissez vous un revendeur ou autre qui pourrait me le communiquer afin que je puisse le transmettre à mon revendeur pour enfin avoir un vélo sorti d’usine.


    Good morning,

    In March 2023, I bought a used Velo fantic Issimo Fun bafang m500 mm engine (G250.250.C.15 033F5TB250001) from a bike rental company (Go Bike 17 Ile de Ré). He had to change the original engine (the old one was out of order). However, we recently noticed that the rear light was not working. We tested it and the controller delivers 3.4V instead of 5.8V.
    5.8V apparently being the right voltage since my wife also has a Fantic bike but with an original motor. On the other hand, as soon as the front light turns on, the battery capacity drops.
    According to the reseller, the problem certainly comes from the wrong software. Unfortunately, this one doesn’t have it. So we are looking for the file CRX10NC3617i142040.6 to return my bike to its original condition.
    Do you have this file? or do you know a dealer or other who could communicate it to me so that I can pass it on to my dealer to finally have a bike from the factory.


  2. R. Theodoropoulos

    BAFANG BBS01B 36V 250W Mid Drive Motor
    After 6 months of normal use without problems the motor makes hard noise has strong vibration and overheats.
    The technician who looked at it found no damage or problems with the sensors

  3. Our motor is not working and we have a flashing wrench on the display. Any idea what might be wrong? Battery shows full.
    Thanks, Jim

  4. I am getting a code21H. Speed sensor malfunction. Is this simply a matter of putting in a new speed sensor? Is this a common problem?

  5. I purchased a Bafang hub motor, I had to order an extension 3 pin male/female cord. This hub motor is on a Sunseeker trike. I’m getting an er 8 code. What’s wrong?

  6. hi, i have a m200 that has power loss when pushed ,would like to get firmware update but can’t find a bike shop to touch it (east midlands gb) can anybody point me in right direction

  7. I’m a little concerned about buying another bafang mid drive, my bbs02 died after only 6 miles. The stator & rotor was found to have overheated. I was using a greenlance 48v 17ah battery & I was riding on the flat, it was November so the ambient temperature had nothing to do with its failure. I’m a mature cyclist & fully understand the limitations of these motors, not overstretching or constant use of throttle.

  8. I have the M600 motor on a 29er MTB. At 5000 kms the main bearing was replaced, now at 6500 the noise from the motor is embarrassing and seems failure is eminent, however it still performs well.
    I would like to send a video of the noise its making….

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