Killed hub motor on 1st run, lots of friction now.

psycotrip

psycotrip

1 mW
Joined
Mar 3, 2018
Messages
19
I JUST got my hub motor installed. It was working just fine got up to a top speed of 33mph. For no reason the bike cut out and gives code 06 from the lcd3. At the same time now the hub is very hard to turn, it was very smooth before. I got a hub motor to avoid drivetrain issues but looks like i drove into one. Nothing is visibly wrong with it as far as i can tell. This seems to be a sealed unit so what should i do, it was from risunmotor.com in china so that's a long way to send back. I guess I need a gear puller and to go from there. The freewheel spins fine btw. And when it happened the chain got loose too, but the axel did not appear to move and the nuts were still tight, the axel is flat on 2 sides to prevent spinning, so i dont think that's what happened.
 
Try disconnecting the controller and see if the friction goes away. It sounds like the controller blew. It is also possible the motor phase wires shorted. If the resistance goes away after unplugging the controller from the motor, it would indicate a blown controller.
 
i disconnected the wires and its the same, if there pinched together on where they exit the motor, will it still be rough even if its disconnected?
 
Good chance the short in the phases also took out the controller.
 
When I wanted to take the cover off my hubmotor this thread was helpful, I had no problem with the 3-4 screwdriver method.

https://endless-sphere.com/forums/viewtopic.php?t=30243
 
well i disconnected it from controller and it spun smooth, should have done that 1st. blown controller, it was registering just under 2000w. I'm surprised it overheated and blew so quick, it had cylinder fuses with it, or does it need a fet replaced, or just replace the controller.
 
Pretty confusing info; one post says it didn't change when you disconnected the motor wires from the controller, and the other post says it did. Which one is what actually was done and what actually happened?

psycotrip said:
i disconnected the wires and its the same,
Click to expand...
psycotrip said:
well i disconnected it from controller and it spun smooth,
Click to expand...
 
i honestly did not think that the controller shorting internally would make the hear hub act like that, i disconnected the battery and hal sensor plug, my mistake
 
psycotrip said:
i honestly did not think that the controller shorting internally would make the hear hub act like that, i disconnected the battery and hal sensor plug, my mistake
Click to expand...

Thanks for clearing that up. Shorted controllers are pretty common. Replacing FETs sometimes fixes them, other times the damage is greater.

I had one controller repaired several times, the final solution was to get a higher current controller. It didn't get hot, but the currents were high enough to blow leads off some FETs.
 
If controller is a KT model (Based on your comment regarding the display being a KT-LCD3), then I would recommend replacing the controller. Another KT controller would be easy to swap out, but they are pretty modest controllers, honestly. The 12FET ones, with pseudo sine wave are decent, though. Get one with irfb3077 or 4110 MOSFETs for sure.

Or just upgrade the controller to something better if you want.
 
Sometimes the cheaper kits will have cheezy controllers that blow immediately. They worked briefly at factory, but not under load.

Bitch at the vendor for a new one.
 
ok this is the controller that came with it and failed
https://risunmotor.com/36v-1200w-48v-1500w-60v-1500w-72v-1500w-ebike-brushless-dc-sinus-controller-regenerative-function.html

i ordered an 1800w controller from them
https://www.ebay.com/itm/RisunMotor-Exclusive-36-48V-1800W-Ebike-Controller-18-MOSFET-50A-E-Bicycle-Part/183031049532?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

i plan on disabling the brake regen and limiting the max current to 80% because the first controller died so quick
 
A good controller should work fine, you just got one with a dud part inside. It happens, they test fine, but then die quick. Just part of the way things work unless they test them harder at the factory.

Bear in mind, a big controller will hit your battery hard, so some way to limit it will help your battery survive it. So you are on the right track.
 
got the controller today much quicker than expected, everything works again. i limited the power to 80% and disabled brake regen to limit the controller heat. the controller that died was in a bag with no airflow and was still red hot after i pedaled it home, pretty sure i cooked that one because the meter was registering just under 2000w, maby too much for the controller.
 
Locating the controller where it gets some air flow will make a huge difference in heat buildup. You can periodically check the temp by hand after running it hard to get a good idea for how hot it's getting. When everything is working properly, you shouldn't have to worry about it.
 
fechter said:
Locating the controller where it gets some air flow will make a huge difference in heat buildup. You can periodically check the temp by hand after running it hard to get a good idea for how hot it's getting. When everything is working properly, you shouldn't have to worry about it.
Click to expand...

Or you could drape some tinfoil over it. Just sayin' ;^)
 
well i blew i 2nd controller, its shorting internally again. i bought a controller and motor tester. https://www.ebay.com/itm/24V-36V-48V-60V-Electro-Car-E-bike-Scooter-Brushless-Motor-Controller-Tester-/192496420473?hash=item2cd1ae4679 . the controller was very hot again, i was just keeping it in the bag they supplied, i guess that's a mistake, i limited the controller power to 80% disabled regen, and im still cooking it with a higher wattage controller, it was reading between 1200w and 1900w during a 10 mile ride at night in near freezing temperatures. I've had enough of this i need some help, do i need a better controller is the motor blowing them up, idk what to do im having a nervous breakdown i have too much into this project and just need to get to work.
 
Don't put a controller in a bag.

Put it in the airflow.

If the controller is in a bag, it can't shed heat anywhere, so it stays inside the controller, and heat kills electronics.


If the controller worked utnil after a ride with it in the bag, then it's almost certainly heat killing it.


Also, even with "kits", the phase and hall wires may not be matched up correctly. This will cause a motor and controller and wiring to get much hotter than normal, and use up battery power at a much higher rate than normal.

If your controller has a "learn" wire jumper, then you use that per the instructions for that specific controller to let it find the right combo on it's own.

If it does not have a learn wire set, then you may have to manually determine what the right combination is. There is a thread and a wiki article just for How to Determine the Wiring for a Brushless Motor / Controller (that may not be it's exact name, but it should be linked in the Sticky Index thread for the Motor Technology section, and probably in Ebike Technical).
 
i just though that using the supplied bag would be ok in the cold, boy was i wrong. why do they even have it like that, setting me up for failure.
 
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