Bafang Electric Bicycle Brushless DC Motor User Manual

1. Product Overview

This manual provides instructions for the Bafang series of rear drive electric bicycle brushless DC motors, including models RM G010.250.D, G020.250.D, G020.350.D, and G040.250.DC. These motors are designed for electric bicycle conversion kits, offering powerful and efficient assistance for various riding conditions.

The geared motor is suitable for pedelecs on long, level roads, urban commuting, touring, or challenging hilly terrains, such as mountain biking. It delivers power efficiently through constant speed and a down gearing ratio of 1:21.9. With a high torque of 120 Nm, it provides ideal support for acceleration from a standstill. The motor is typically available in black.

2. Specifications

Image: Certificates of compliance, including RoHS and CE, for electric bicycle components.

3. Setup and Installation

Proper installation is crucial for the safe and efficient operation of your Bafang electric bicycle motor kit. Please follow these guidelines carefully.

3.1 Pre-Installation Checks

Before beginning the conversion, it is important to measure your bicycle's dimensions and confirm its brake type.

• Measure the front fork open size.
• Confirm your bike's brake type (V-brake, disc brake, or roller brake).

Image: Diagram illustrating how to measure the front fork open size (e.g., 100mm) and details for V-brake (85-90mm) and disc brake (100mm, 44mm symmetry hole, 22mm nearby hole) compatibility. Note: If the groove size is too small, polishing may be required.

3.2 Motor Installation

The kit includes either a front/rear hub motor or a mid-drive center crank motor. Ensure you have the correct motor type for your bicycle frame.

Image: Bafang RM G010.250.D rear drive hub motor in black, showing its design and cable exit point.

Image: Bafang RM G010.250.D rear drive hub motor in silver, illustrating its dimensions and axle length for compatibility with 20-700c bikes.

Image: Bafang mid-drive motor, highlighting its robust construction and central mounting for optimal weight distribution.

Image: A complete Bafang mid-drive motor kit, showing the motor, chainring, display unit (C961), brake levers, wiring, and various mounting hardware.

3.3 Wiring the Controller and Components

The kit includes a smart controller with waterproof cables and connectors, designed for a one-cable system (1-to-4). Refer to the electric circuit diagram for your specific model.

Image: Wiring diagram for the brushless DC motor controller. Connections include: Brake, Hall Sensor and Speed Sensor, Display, Power +, Power -, Throttle, PAS (Pedal Assist System), Motor A, Motor B, Motor C, and 36V Front and Rear Light.

3.4 Accessory Installation

Install optional components such as the throttle and pedal assist sensor.

Image: Wuxing twist throttle for speed control and a pedal assist sensor, showing its mounting on the crank arm.

3.5 Final Assembly

Some parts may be removed for packaging. You will need to assemble these upon receipt. A professional tool bag is typically included to assist with assembly.

• Attach pedals (if applicable).
• Install mirrors (if applicable).
• Mount the front wheel.
• Attach the front fender.
• Install the rear trunk (if applicable).

4. Operating Instructions

Your Bafang electric bicycle motor kit is equipped with a display unit to monitor and control various functions.

4.1 Display Functions

The display unit (LED or LCD) provides essential information and control over your e-bike's functions.

Image: Various LCD display options (LCD5, LCD2, LCD3) showing functions such as speed, range, time, voltage, power switch, pedal assist function switch, and speed levels switch.

Image: Detailed LED display unit. Key elements include: (1) ON/OFF button, (2) Operation button, (3) MODE button, (4) 6KM/H button (boost function), (5) Speed indicator dial (15 LED indicators), (6) Battery capacity indicator (4 LED indicators), (7) Power ratio gear (3 LED indicators).

4.2 Speed Control

Use the throttle (if installed) or the pedal assist system (PAS) to control your speed. The display will show your current speed and assist level.

4.3 Battery Management

Monitor the battery capacity indicator on your display. Ensure the battery is adequately charged before each ride.

5. Maintenance

Regular maintenance ensures the longevity and optimal performance of your Bafang electric bicycle motor kit.

5.1 Battery Care

• Charge the lithium battery using the provided AC/DC 110V-240V smart charger.
• Charging time typically ranges from 4 to 8 hours, depending on the battery's capacity.
• Avoid overcharging or completely draining the battery to prolong its lifespan.
• Store the battery in a cool, dry place when not in use.

5.2 Motor and Controller

• Keep the motor and controller free from excessive dirt and moisture.
• Periodically inspect all cables and connectors for signs of wear, damage, or loose connections. Ensure waterproof connections are sealed properly.
• Clean the motor and controller housing with a damp cloth; avoid direct water spray.

5.3 General Inspection

• Regularly check all mounting bolts and fasteners for tightness.
• Inspect the wheel rim and spokes for any damage or misalignment.
• Ensure brake levers and sensors are functioning correctly.

6. Troubleshooting

If you encounter issues with your Bafang electric bicycle motor kit, consider the following basic troubleshooting steps. For complex problems, please contact technical support.

• No Power: Check all cable connections, especially the main power cable from the battery to the controller. Ensure the battery is charged.
• Motor Not Engaging: Verify that the display is on and showing an assist level. Check the PAS sensor and throttle connections. Ensure brake levers are not engaged, as some systems cut power when brakes are applied.
• Intermittent Power: Inspect all wiring for loose connections or damage. Ensure the battery is securely mounted and making good contact.
• Unusual Noises: Discontinue use immediately and inspect the motor for any obstructions or signs of physical damage.

If these steps do not resolve the issue, please refer to the warranty and technical support information below.

7. Warranty and Support

7.1 Warranty Policy

The Bafang electric bicycle motor kit comes with the following warranty periods:

• Main Electronic Parts (Charger, Controller, Battery): 6 months warranty.
• Motor: 12 months warranty.
• Frame, Handlebar, Stem, Wheel Rim: 2 years warranty.

Warranty Exclusions: The warranty does not cover damages caused by:

• Human factors (e.g., misuse, accidents).
• Dismounting any parts without professional technical personnel.
• Using non-original or unauthorized parts with the electric bike or scooter.
• Traffic accidents or other external accidents.
• Problems caused by overloading the system.

7.2 Technical Support

For technical assistance, please utilize the following resources:

• An electric circuit diagram is provided for each model to aid in wiring and troubleshooting.
• Training for 1 or 2 technical workers can be provided free of charge.
• In cases of serious problems that cannot be resolved by local technicians, an engineer may be dispatched to the customer's location for assistance.