Can anyone help me identify what’s going on? As I’m riding, the mid drive motor on my E bike sometimes starts making a whirring noise and then loses power. The console and lights remains on but the motor doesn’t give any more assist. When I turn the power off and back on, it works again. Does anyone know if this is more likely to be a battery issue or a motor issue?
I’ve taken it into a mechanic that specializes in E bikes already, but the business was brand new and, based on my discussions with them, I didn’t trust that they knew what they were talking about. I feel like, when it comes to E bike repair, it’s the wild west out there.
I do not own a mid drive but when stuff like that powers down but then comes back up again, I immediately think it is a loose connection. I know that’s probably very obvious, but before you do anything else, look at the wiring from the controller to the motor and the motor to the battery. If it is older than a few months there might be wear and tear or water intrusion.
You also might want to find a forum that is specific to that brand of motor and brand of bike to see if it is a common problem.
I’m definitely no expert but I’ve owned a mid drive for a few years. It could possibly be the nylon gears transferring power from the motor to the bike’s gears- that happened to me early on. I’d go full throttle from a dead stop and eventually the gears sheared and binded.
Otherwise, depending on the actual sound it could be the driver fets or the motor itself. Can you post a short video or audio clip of it happening? Also does it only happen under load or can you trigger it with the back wheel off the ground?
The bike is in the shop for a separate reason but when it’s back I’ll test it out. What would it mean if it only happens under load or not?
If it only happens under load, that would make me suspect the motor driver. It sounds like the circuitry isn’t able to handle much current anymore, which would cause it to basically lock itself out for safety, until it’s power cycled. Most likely such a scenario isn’t communicated to the display.
Under load would refer to when you’re on the bike and activating the motor vs lifting the rear wheel of the bike off the ground and activating the motor.
Check all the connections, sounds like a loose wire.
Post pics, more details, and probably make sure your cables are securely connected.
