Help! Broken rear hub motor?

Johnwat1980

Pedelecer
Aug 11, 2020
25
8
41
Newcastle upon Tyne
Hi all

I’m wondering if anyone can shed some light on what happened to my ebike today……on the way back from work I was nearly home everything was fine then I stopped to look at the view then when I went to start peddling again I got violent vibration from the motor and barely any power same with the throttle just vibrating with little power I pushed it the rest of the way back as the vibrating was so intense I thought it might blow up or something I haven’t had it long about 8 months it’s a diy ebike 1000w rear hub motor 48 volt battery worked seamlessly all that time then that it’s just weird how it just happened like that…. Had a look at all phase wire and hall sense wires they seem fine I’m stumped and if anyone could help me out with some info or solution I would be extremely grateful……..thanks in advance……..John
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
14,561
5,650
58
West Sx RH
Does it have learning wires ?
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
14,561
5,650
58
West Sx RH
Can you post a short film of the violent vibration as the symptom sounds very unusual.
Is the sound an electrical one. aloud cracking interruption noise ?
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,931
Basildon
It's not the motor that has the problem. It's either the motor cable or the controller.

The first thing to check is all the connections in the motor cable. If you have the standard 9 pin connector, it has to be ALL THE WAY IN to the MARKED line, not just in tight. Also, check any bullet connectors you have at the controller end. Pull them apart and crimp the barrels so that they're nice and tight.

Next, lift the wheel off the ground and turn it by hand. You just be able to feel a bit of notchiness as each magnet goes past each pole. If there's any resistance, disconnect the motor from the controller and try again. If it frees up, you've blown a mosfet in the controller. The biggest current through the mosfets is at start-up, so that's when they're most likely to blow.

There are other random wiring defcts that can cause your problem. Do the above checks then rport back.
 

Johnwat1980

Pedelecer
Aug 11, 2020
25
8
41
Newcastle upon Tyne
Thanks for your reply’s I will give them a try I do have a spare controller just means I have to change some of the connectors they different if it is that when I figure it out I will post all about it I just spent about 80 pound on bloody tyres because I kept getting punctures so i was having a melt down when this happened but anyway thanks again much appreciated
 

Johnwat1980

Pedelecer
Aug 11, 2020
25
8
41
Newcastle upon Tyne
It's not the motor that has the problem. It's either the motor cable or the controller.

The first thing to check is all the connections in the motor cable. If you have the standard 9 pin connector, it has to be ALL THE WAY IN to the MARKED line, not just in tight. Also, check any bullet connectors you have at the controller end. Pull them apart and crimp the barrels so that they're nice and tight.

Next, lift the wheel off the ground and turn it by hand. You just be able to feel a bit of notchiness as each magnet goes past each pole. If there's any resistance, disconnect the motor from the controller and try again. If it frees up, you've blown a mosfet in the controller. The biggest current through the mosfets is at start-up, so that's when they're most likely to blow.

There are other random wiring defcts that can cause your problem. Do the above checks then rport back.
Turned out it was the hub motor wires where to tightly secured to my frame loosened them off and everything works fine haha
 
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Tony1951

Pedelecer
Mar 27, 2016
198
95
70
Turned out it was the hub motor wires where to tightly secured to my frame loosened them off and everything works fine haha
Good that you are on the right track but I would be checking the associated connections. There is something insecure relating to the wires or possibly shorting when tightly strapped down.
 
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