Bike Wheel stopped working.. smoke from battery pack

Greetings people,

I have a 48 V 1000W ebay motor kit. I rode about 2 blocks, I was going about 12 mph, then I heard a rubbing noise. The bike stopped working via the throttle. The wheel no longer spins freely like it did before; there is more resistance on the wheel than when I bought it.

Any thoughts?

Thanks

My guess is phase wires shorted. Check if the axle spun in the dropouts, or wire pinched. Else, it could be only mechanical friction: wheel rubbing on the frame, brakes stucked...

Can also be blown controller (shorted FETs).

If you spin the motor by hand, with or without the battery connected, does it feel like the motor spins less freely than it used to?

If so, try disconnecting the controller from the motor, and retest.

If it then spins freely, the controller probably has blown FETs.

If it still does not spin freely, then it's possible a pair of phase wires have melted together, perhaps inside the axle or motor.


For the smoke from the battery pack, that could have been the BMS FETs blowing. You'd have to use a multimeter on the output to see if it is still outputting the correct voltage. If not, there are hundreds of battery pack troubleshooting threads to show you how to test it.

Some of the threads in this search are relevant, most are not
https://endless-sphere.com/forums/search.php?keywords=battery+help&terms=all&author=&sc=1&sf=titleonly&sk=t&sd=d&sr=topics&st=0&ch=300&t=0&submit=Search
there isn't a quick easy single search that will find all of them, unfortunately.

I also vote for blown controller. This is not unusual for kits in that price range.

if smoke actually came from the battery, not the controller, then you have several problems.

Controllers have to be outside the bag, if you crammed it in with the battery.

Look where the phase wires come out of the controller. That's the most likely place they've melted.

Thank you for the prompt reply I hope to keep you people posted... dun dun dun ITGLW

lol, yeah, this happened to me a month ago. blown phase wires inside the controller, which was overheating inside the frame bag. oops! Made the wheel hard to spin, smoke coming from the battery bag, and everything.

Those fantastically reliable eBay kits ala wesnewell.

Its a coin flip on those cheap controllers, whether in a kit, or bought cheap a la carte on ebay. I find they usually last at least a year, but one in a hundred or so will croak almost immediately. just make em send you another, and another, as needed till you have one that lasts more than a week.

I completely disconnected the controller and it SPINS FREELY AGAIN The thick green yellow and blue wires where left; I disconnected the other wires when it stopped and it would not spin freely.

I looked inside the speed controller and I did not see anything burnt or fuses popped.

Now I am wondering if I can put a 24V controller on a 48V wheel







Thanks for all the replies and shalom IOU

Most likely a phase or hall connection came loose or wasn't connected properly. That explains the rubbing noise when the controller is out of sync with the motor, then, when you continue with the throttle on, you blow mosfets in the controller. That rubbing/grating feels like a mechanical problem but in most cases it isn't. It's electrical.

To test: rotate the wheel when disconnected. If the resistance goes away, you need a controller. If it doesn't, you have a short in the motor or its phase wires.

You can only drive the wheel with a controller. If you connect a battery directly to it, you'll get more damage.

d8veh said:

Most likely a phase or hall connection came loose or wasn't connected properly. That explains the rubbing noise when the controller is out of sync with the motor, then, when you continue with the throttle on, you blow mosfets in the controller. That rubbing/grating feels like a mechanical problem but in most cases it isn't. It's electrical.

To test: rotate the wheel when disconnected. If the resistance goes away, you need a controller. If it doesn't, you have a short in the motor or its phase wires.

You can only drive the wheel with a controller. If you connect a battery directly to it, you'll get more damage.

Click to expand...

Thanks for the info @d8veh!

I was not going to hook it up directly to battery

I finally hooked everything back up, improved the harness and it sparks at the battery as soon as I connect the battery.

Do rear, front and mid drive bikes have interchangeable controllers?

SO I think I learned that I have a blown mosfet? I tried to test the controller and it is showing continuous between the black and red wire. I guess I will solder in some mosfets and see if that fixes the problem. Trial and error