Electric motor issue

[Lcurran11]

Question for the group if someone can help me. I had a chain jump off and damaged wires coming out through the hub/axle. I’ve separated to ensure no shorts I think but it’s strange the motor only engages with throttle when I free spin the tire backwards and then it engages in proper forward direction. It doesn’t work when I pedal or spin tire in forward direction. Assume I am missing a short or something? I tried disconnecting brake wires but no luck.

 

[harryS]

Damaged wires means the insulation was cut and the copper shorted out? When that happens, it can short circuit components in the wheel or controller. Separating the wires later won;t help if there was already electrical damage..
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You;'re saying the bike doesn't work under pedal assist or throttle? It only works if you spin the wheel backwards and apply throttle? Probably a bad sensor in motor. Do you want to diagnose and fix it yourself?

 

[Lcurran11]

Ideally yea. It’s a low value bike for my kid. Poor design that didn’t protect the wires properly unfortunately

 

[PedalUma]

he motor only engages with throttle when I free spin the tire backwards

@harryS is correct. Do you have any error codes on the display? Either the short messed up the inside of the motor or the controller. What is the bike and can you show some photos? It is a hub-drive and those cores can be swapped.

 

[AHicks]

Damaged wires means the insulation was cut and the copper shorted out? When that happens, it can short circuit components in the wheel or controller. Separating the wires later won;t help if there was already electrical damage..
.
You;'re saying the bike doesn't work under pedal assist or throttle? It only works if you spin the wheel backwards and apply throttle? Probably a bad sensor in motor. Do you want to diagnose and fix it yourself?

You need to answer the highlighted question. Sure there's a chance the issue is electrical, but if you can't turn the crank/pedals (forward) and have the rear tire turn, you may have a mechanical issue - not electrical.

 

[Lcurran11]

It doesn’t appear to be anything mechanical. I can pedal fine and it freewheels fine but there is no propulsion from the electric motor with the throttle depressed until I spin the tire backwards

 

[Lcurran11]

I will try to get some pictures when I get home from work.

 

[Lcurran11]

 

[Lcurran11]

Trying to attach a video but not sure I can do so

 

[rich c]

That's not a motor problem, that is a wiring issue. The cord must be replaced.

 

[Lcurran11]

Oh for sure wires are damaged I just didn’t understand why it actually works when I spin the tire backwards but not forwards?

 

[Lcurran11]

I’d attach a video if I could

 

[tomjasz]

Oh for sure wires are damaged I just didn’t understand why it actually works when I spin the tire backwards but not forwards?

The wire are still or were shorted messing up the hall sensors.

These links should clarify the issue.

replace hub motor hall sensors