Coaster brake with Bafang or CYC motor

If there is a coaster brake on the bike to be converted, it can unfortunately no longer be used after the conversion. It is no longer “accessible”. You can see why this is the case in the following video. We recommend subscribing to our YouTube channel so that you don’t miss any more videos.

As can be seen in the video, the 3 teeth of the freewheel engage with the internal teeth of the large gearwheel. When the crank moves backwards, the teeth “slip” over the internal toothing, so that there is no firm connection.

Some people have also had the idea of gluing in the clutch. This would connect it firmly to the large gearbox (and therefore also to the chainring). The disadvantage of this, however, is that the cranks have to rotate with the throttle and there is no crank signaling to stop the motor assistance. This is usually done by stopping the crank movement – this is registered via the PAS disk and PAS sensor board. In addition, the motor cannot rotate the chainring faster than the crank movement.

Conclusion: A back-pedal brake is not suitable for this purpose and should be replaced by a conventional brake (cable or disc brake) after conversion.