broken cable help

Scruffydroid

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Dec 12, 2020
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It's hard to say, depending on your skill level and how damaged they are.

I've used a thread file but he also used a Wheel Stud Hub Thread Restorer**M12 x 1.25**M12 x 1.5**M14 x 1.5mm 3 Dies to repair threads.

You will definitely need new nuts, and each time you thread the old ones back onto the axle, you are damaging it more.

You might just be heading down a rabbit hole, and be better off buying a new rear hub motor kit and use the broken one to take a chance with honing your mechanical skills?
 

billyboya

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It's hard to say, depending on your skill level and how damaged they are.

I've used a thread file but he also used a Wheel Stud Hub Thread Restorer**M12 x 1.25**M12 x 1.5**M14 x 1.5mm 3 Dies to repair threads.

You will definitely need new nuts, and each time you thread the old ones back onto the axle, you are damaging it more.

You might just be heading down a rabbit hole, and be better off buying a new rear hub motor kit and use the broken one to take a chance with honing your mechanical skills?

Whats a rear hub motor kit. its a electric moped

I think why this cable twisted was because on the opposite side of wheel I never had any rotation or torque washers I maybe wrong
 

Nealh

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I wouldn't worry about the axle threads /nuts as they have stayed put and haven't come loose yet. Simply get the Torque arms fitted on both side and secure them utilising that threaded tap hole, if bothered about the scaremongering of ruined threads clean them and the nuts with isopropanol and then apply some loctite thread compound.
I have an ebike with worn threads and have yet to have the nut loosen once tightened up.
 

Scruffydroid

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Dec 12, 2020
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Ok, fair enough.

Good luck with fixing the moped using the tips above ^

I think it might help if you post a photo of the whole moped?
 

billyboya

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I wouldn't worry about the axle threads /nuts as they have stayed put and haven't come loose yet. Simply get the Torque arms fitted on both side and secure them utilising that threaded tap hole, if bothered about the scaremongering of ruined threads clean them and the nuts with isopropanol and then apply some loctite thread compound.
I have an ebike with worn threads and have yet to have the nut loosen once tightened up.

do you mean this. do it make a seal to stop nuts turning

 
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Nealh

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Loctite sell a number of spec'd thread lock depending on the severity /force one want's a nut to be held in place.
The 243 is a pretty medium universal thread lock to use and doesn't need the axle /nut to be spotlessly clean, the compound acts like a nylon lock nut and will take up any play there is between threads.
 
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billyboya

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I have just fitted wheel temp to test a new throttle, now when you press down on throttle back wheel locks up, cant really understand this now as it worked fine before, it dont even run now I soldered the 3 phase wires blue to blue, green to green, and yellow to yellow. also soldered 5 sensor wires to the board correct too
 

Nealh

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I will start the ball rolling as I mentioned in the PM.
Test and test a again, it's the only way.
It worked to a degree before the wire became twisted and broken, so the shorting that will have occurred has either blown the Halls again or the controller mosfets.
Voltage test the Halls as before and resistance test the controller phases to see if the fets have blown.
It's annoying and probably testing your patience now but it's the only way to go after an occurrence like the motor cable breaking.
 

billyboya

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="Nealh
You will have to go through all the tests again to find the fault.
The twisting and shorting of the wires has either blow the Halls in the motor or Blown/shorted the controller mosfets, only by testing will you know.
Disconnect the controller Phase wires and if the motor turns by hand ok then it is likely a controller mosfet or mosfets have failed. Confirm by mosfet resistance testing.
I have just removed phase wires from the junction box what go to controller, and wheel does turn freely, but if you touch 2 phase wires together on the cable then it seems there is a brake sticking but obviously no brakes fitted as of yet, its a test I learnt on youtube to test phase wires
 

billyboya

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I will start the ball rolling as I mentioned in the PM.
Test and test a again, it's the only way.
It worked to a degree before the wire became twisted and broken, so the shorting that will have occurred has either blown the Halls again or the controller mosfets.
Voltage test the Halls as before and resistance test the controller phases to see if the fets have blown.
It's annoying and probably testing your patience now but it's the only way to go after an occurrence like the motor cable breaking.

I do apologies for all this but Im nearly getting to the stage of calling a scrap dealer, as I honestly thought after all this time, it was ok. I go for 1st dam test drive after 3 months of fixing it. go just less than 1/4 of a mile only for cable to twist and break.

Im afraid Nealh you will have to show me in very simple terms how now do I test the halls, and the controller mosfets. please make it as simple as possible LOL

when you say if the motor turns by hand you mean wheel dont you
 
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Nealh

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You have show that the motor wheel frees up and turns by disconnecting the controller so rules out the motor phases and cable as the issue.
I have already described the process in you other many threads or in the PM's.

Follow the two pdf links for testing.
BlownMosfets.cdr (ebikes.ca)

HallSensorTesting.cdr (ebikes.ca)
 

billyboya

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You have show that the motor wheel frees up and turns by disconnecting the controller so rules out the motor phases and cable as the issue.
I have already described the process in you other many threads or in the PM's.

Follow the two pdf links for testing.
BlownMosfets.cdr (ebikes.ca)

HallSensorTesting.cdr (ebikes.ca)


ok I will do this later, but just feel this has been going on a good 3 months, But as long as you dont mind helping I do appreciate it lots. are mosfets easy then to replace

I cant seem to find which wire is the ground one. I have a cut out switch with a green/yellow wire which goes to the thick red on controller. is that the ground one.

or is it that black thick wire coming from the controller

are all mine suppose to say 10 ohms like in test as I’m still struggling to find where ground wire is

OK I have done the hall sensors 1st, will try mosfet test later. But it does now seem it could be 2 hall sensors the yellow and blue ones. how do I know what sensors to buy same also with the mosfets,

red + black = 4.31v

black + yellow= 0.13v

black + blue= 2.46v

black+ green= 4.99v

Well I tried the mosfet tests, with ground and no power. the only wire which must be ground is that thick black one coming from controller.

but numbers on each wire test flashed up fast then back to 1. on all 3 phase wires green, blue & yellow

But on the power test it was this

power+green= 498
power+blue= 506
power+yellow= 496

hope this is right now, but it seems to me just 2 hall sensors need replacing, the yellow and blue ones. I don't know if that's right. But I will remove motor cases and check again

Am I doing something wrong as in this video he dont even connect to the power and all his readings stay on the screen. yet mine just flash back to 1. thats no power



Wont it just be easier to replace all 3 sensors in motor, then at least I will know they all fine. then just see if motor runs, if not then it has to be the mosfets. But I dont know what sensors to buy or even mosfets hopefully its not the mosfets
 
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billyboya

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I seem to now be getting proper readings on the mosfet tests as I have now set meter to 200 ohm mode. I will test again and get back to you. Tomorrow
 

Nealh

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One can only know where the fault lies by testing, guessing or hoping get's you know where when you don't get the answer you were looking for.

Mosfet's are in the controller, one must test them with no power as it is a resistance test using the 20 or 200 ohms range.
Test Black controller wire to the three phases, one usually see's high 9 ohms or occasionally 10 with no power. It really depends on the spec's of the resistance range of the mosfet's.
Then test Red controller wire to phases with no power, the results will be different to the above ones. You may just see 1 as the result or see an ascending numeral result which is fine, if any give a zero result then they are fried.

Two Halls are fried so one will have to go through repairing them.
Usually ss41F bipolar ones, I paid £2.99 recently for three.
Hall Sensor Bipolar 41F SS41 SH41 SS41F Electric Bike Motor Repair with Guide UK | eBay
 
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billyboya

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One can only know where the fault lies by testing, guessing or hoping get you know where when you don;t get the answer you were looking for.

Mosfet's are in the controller, one must test them with no power as it is a resistance test using the 20 or 200 ohms range.
Test Black controller wire to the three phases, one usually see's high 9 ohms or occasionally 10 with no power. It really depends on the spec's of the resistance range of the mosfet's.
Then test Red controller wire to phases with no power, the results will be different to the above ones. You may just see 1 as the result or see an ascending numeral result which is fine, if any give a zero result then they are fried.

Two Halls are fried so one will have to go through repairing them.
Usually ss41F bipolar ones, I paid £2.99 recently for three.
Hall Sensor Bipolar 41F SS41 SH41 SS41F Electric Bike Motor Repair with Guide UK | eBay
Hi Nealh firstly I am so grateful for all your help, its most appreciated, I honestly thought after 3 months fixing moped. I was all done. and like I said took it less than 1/4 mile not even that, and bugger me, cable twisted, but that's my fault for not having the proper washers on axle etc. But I have now received more nuts anti rotation washers plus torque washers from Erider.

anyway I have now done the mosfet tests, I always thought when it said with power, it was to have battery connected then test. or am I wrong or is it like you said thick red wire is the power. anyway now I have put multimeter on 200ohms setting I'm getting proper readings now. but when i had meter on diode and continuity mode numbers wont read right anyway here is readings below, it seems thank god my mosfets are ok

the numbers was going up fast at 1st then slowed

no power thick blck wire on controller

green= 08.0v
blue= 09.7v
yellow= 09.7v

no power thick red wire on controller


green=17.4v
blue=19.1v
yellow=18.5v

are all hall sensors same sizes then, I have ordered 3 new ones where you said. cheap enough £1 each. but it seems you have to make sure the legs of the sensors don't touch, so not much solder will be needed on each leg. I did see on you tube that you glue in the sensors, is that true then here are images of my sensors,


 

Nealh

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The mosfets don't give a voltage reading, the reading is ohms resistance.
The one at 8 ohms is quite low and is weaker then the other two it should be nearer to 9.7 ohms.

The Halls will have an identifier number on them, I can't read them as the pic is of poor resolution when blown up. Use a mag glass to red them.
 

Nealh

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The Green/Yellow phase wires look fried to me and looks like the Green has overheated and the core visible.

The Halls, one has to solder the correct leg and check they are orientated right as they only fit one one with bevelled edge. Use the white sheath to insulate the legs when soldered.