DJ bike rear hub wiring

[Terry180]

500w rear hub on a dj mountain bike, broken wires at axle, any suggestions who would be able to put in a new cable

 

[harryS]

Picture?

 

[Terry180]

I don’t have a picture at this moment. One of the wires on the power code going into the rear hub has the insulation off causing it to short to the axle.

 

[Terry180]

Not the actual picture but shows the same problem

 

[harryS]

Doesn't help. Did your wire break that close to the motor? Does it go thru the axle or thru a hole in the side of the housing?

If you have to pay someone to fix what was in the picture, I think it's comparable to buying a whole new motor if he's charging what his time is worth. He's already taken the motor apart. He probably has to get a spare cable and put it in the motor, and then solder it up. While it's all apart, he should test the three position sensors and possibly a speed sensor to make sure they weren't damaged too. This is the kind of stuff where a DIY guy has to get dirty and do it alone if the repair bill is going to be minimized.

 

[Terry180]

The wiring loom goes thru the axle the exposed wire looks like it was do to rubbing at the slot opening in the axle, going to take the wheel off this morning and see if I can some how insulate the wire.

 

[harryS]

Depends what you got. Liquid electrical tape might work on just one wire. If you have several, you would need to add some extra help, like maybe splitting a thin sleeve and using it to cover the frayed areas, along with the liquid rubber.

It's good stuff. Has its limits.

 

[Sierratim]

Heat shrink tubing could also work. I keep a selection of sizes around the shop for misc electrical repairs. For smaller sizes/diameters I've had good results using a hair dryer on high to shrink the tubing (don't tell my wife..).

If you don't want to remove connectors from the end of the wire needing the insulation repair, this heat shrink product might do it for you;

I haven't used this, but it looks promising.

 

[Terry180]

I was able to isolate the wire and using electrical tape to isolate it from the axle shaft, turn on the battery, display is functional but when I use the throttle a code 24 comes on, motor hall signal, indicating no connection between motor and controller, I guess that why I picked it up for $100,

 

[harryS]

There's three thick wires that run the motor coils at 48 vo0lts. There's five or six thin wires that power three hall sensors, and possibly one speed sensor. The latter are all powered by 5 volts. When 48Volts crosses 5 volts, poof. Sensors blow up.

Worse things could happen if the damage travels back into the controller, and pops the 5 volt input circuits.

The next step is to learn how to test Hall sensors to find out if the ones in the motor stillwork. You need a multimeter.