Bafang Speed Sensor – Original Sensor for 250W-1000W Motors

The Bafang speed sensor is an original electronic component of the e-bike drive system. It fits all Bafang 250W, 350W, 500W, 750W and 1000W motors. The sensor sends 1 pulse per wheel revolution to the controller. As a result, your display shows an accurate speed reading at all times.

This part operates on a 4.2-5.5 V DC input voltage supplied directly by the Bafang controller. It uses an M3.10 connector and an 80 mm cable. The sensing distance to the magnet is 4 mm. Furthermore, the system uses these same pulses to calculate the pedal assist speed limit.

Installation follows a simple layout. The sensor mounts to the frame, while the magnet attaches to a rear wheel spoke. Moreover, the part suits both mid-drive motors and hub motors from Bafang conversion kits. Therefore, riders use it as a replacement part and as a component when assembling a new system.

Key Benefits and Advantages

• Compatibility across the full Bafang range – works with 250W, 350W, 500W, 750W and 1000W motors.
• 1 pulse per revolution – a clear signal reaches the controller on every wheel rotation.
• Wide 4.2-5.5 V DC input range – the sensor draws power straight from the Bafang controller.
• Operating temperature from -20 °C to 45 °C – suitable for riding through the cold season.
• 4 mm sensing distance – the magnet is detected reliably without fine adjustment.
• M3.10 connector type – plugs into the standard Bafang wiring harness without adapters.
• 80 mm cable – compact routing at the rear section of the frame.
• Original Bafang part – identical to the sensor fitted at the factory.

Who Is This Product For?

This sensor is made for e-bikes running a Bafang 250W, Bafang 350W, Bafang 500W, Bafang 750W or Bafang 1000W motor. That coverage includes both mid-drive and hub Bafang motors. Consequently, one part number serves a wide range of builds.

Riders typically choose it when the speed reading disappears from the display. It also helps when pedal assist stops engaging smoothly. In addition, the sensor is needed when assembling a Bafang conversion kit and the original unit is damaged or lost.

However, this sensor does not suit systems from other manufacturers. It is designed for Bafang controllers only, because its power supply and pulse signal follow the Bafang wiring harness standard.

Technical Specifications

Why Choose the Bafang Speed Sensor?

This is an original Bafang part with an M3.10 connector. Therefore, no rewiring or soldering of the harness is required. The connector plugs straight into the Bafang controller.

The declared 4 mm sensing distance defines the exact gap between the sensor and the magnet. Because of that figure, installation involves no guesswork. Simply hold that gap, and the speed reading stays stable.

Speed accuracy depends on two things. First, the 4 mm gap must be maintained. Second, the wheel size must be set correctly on the display. So after fitting the sensor, it is worth checking the wheel size setting on the control unit.

Frequently Asked Questions

Which Bafang motors work with this speed sensor?

• It suits Bafang 250W, 350W, 500W, 750W and 1000W motors.
• It works with both mid-drive and hub Bafang motors.
• It is built for Bafang systems only and is not adapted to other controllers.

How does a speed sensor differ from a cadence sensor?

• The Bafang speed sensor measures wheel revolutions at 1 pulse per revolution.
• A cadence sensor measures pedal rotation instead of wheel speed.
• These two parts are not interchangeable.

What voltage powers this sensor?

• The input voltage is 4.2-5.5 V DC.
• Power arrives directly from the Bafang controller through the M3.10 connector.
• No separate power source is needed.

What gap should there be between the sensor and the magnet?

• The sensing distance is 4 mm between the sensor and the magnet.
• The magnet mounts on a rear wheel spoke.
• The sensor mounts to the frame, aligned with the path of the magnet.

Will this sensor fit a Bafang conversion kit?

• Yes, it fits hub motors from Bafang conversion kits.
• It equally fits Bafang mid-drive builds.
• The M3.10 connector matches the standard kit harness, so no adapter is used.

Does it work in cold weather?

• The operating temperature range runs from -20 °C to 45 °C.
• That range covers winter riding as well as summer use.

Why does my display show the wrong speed after fitting?

• Check that the 4 mm gap to the magnet is maintained.
• Then confirm the wheel size setting on the control unit.
• Both values together determine the accuracy of the reading.

With an 80 mm cable, an M3.10 plug and a 4 mm sensing gap, this original Bafang sensor restores accurate speed data and smooth pedal assist on 250W through 1000W builds. Fit it to the frame, align the spoke magnet, and confirm the wheel size on your display.