Juddering from bike and power cut

[UrbanPuma]

Hi all,

My Powacycle Puma suddenly juddered from take off using the throttle only, then power cut out, but indicator lights were still on. I thought it was a phase wire issue, but after checking those this appears not to be the cause.

I tried riding it afterwards: on startup it juddered again, the range reduced on the battery indicator and the 'overload indicator started flashing orange whilst moving.

Does anyone have any ideas what the problem is?

Thanks

 

[vfr400]

Hi all,

My Powacycle Puma suddenly juddered from take off using the throttle only, then power cut out, but indicator lights were still on. I thought it was a phase wire issue, but after checking those this appears not to be the cause.

I tried riding it afterwards: on startup it juddered again, the range reduced on the battery indicator and the 'overload indicator started flashing orange whilst moving.

Does anyone have any ideas what the problem is?

Thanks

They are the symptoms of a blown mosfet in the controller or faulty connection to the motor. The latter often causes the former.

 

[UrbanPuma]

They are the symptoms of a blown mosfet in the controller or faulty connection to the motor. The latter often causes the former.

Bummer. How can I check to know for sure?

 

[vfr400]

Bummer. How can I check to know for sure?

There's nothing to test if it's running properly. You can only find faults when it isn't.

 

[Andy-Mat]

Bummer. How can I check to know for sure?

Bummer. How can I check to know for sure?

It really depends upon your knowledge or that of any electronic friends you have.
IMHO its not difficult, but you do have to have a reasonable level of knowledge of safety procedures and also about the possible dangers with regard to e-bike batteries.
I have added a few YouTube videos, for you to look at, but I am not under any circumstances recommending that you do this yourself!
Its "Information Only", hopefully allowing you to make a correct and safe decision as how to proceed further.

I or vfr400, would test the MOSFETs, and replace any that are defective, but I have many years of experience in electronics, probably more years than you have been on this earth, so the decision for myself is quite simple.
I also have the necessary equipment at home and how to use it correctly.

Do please ask us all here if you have any further questions, as we are all here to help.
Andy

 

[UrbanPuma]

It really depends upon your knowledge or that of any electronic friends you have.
IMHO its not difficult, but you do have to have a reasonable level of knowledge of safety procedures and also about the possible dangers with regard to e-bike batteries.
I have added a few YouTube videos, for you to look at, but I am not under any circumstances recommending that you do this yourself!
Its "Information Only", hopefully allowing you to make a correct and safe decision as how to proceed further.

I or vfr400, would test the MOSFETs, and replace any that are defective, but I have many years of experience in electronics, probably more years than you have been on this earth, so the decision for myself is quite simple.
I also have the necessary equipment at home and how to use it correctly.

Do please ask us all here if you have any further questions, as we are all here to help.
Andy

Thanks for the videos Andy-Mat, I watched the first one and found it very informative. At this stage, I won't attempt anything as I don't have the tools or knowledge...I'll just watch the other two videos to gain more of an understanding of mosfets.

Aside from that, what confuses me is where to put the multimeter to test my battery life - it's 8 years old. I have a multimeter.

I'll definitely be back with more questions, thank you very much for this.

 

[UrbanPuma]

It really depends upon your knowledge or that of any electronic friends you have.
IMHO its not difficult, but you do have to have a reasonable level of knowledge of safety procedures and also about the possible dangers with regard to e-bike batteries.
I have added a few YouTube videos, for you to look at, but I am not under any circumstances recommending that you do this yourself!
Its "Information Only", hopefully allowing you to make a correct and safe decision as how to proceed further.

I or vfr400, would test the MOSFETs, and replace any that are defective, but I have many years of experience in electronics, probably more years than you have been on this earth, so the decision for myself is quite simple.
I also have the necessary equipment at home and how to use it correctly.

Do please ask us all here if you have any further questions, as we are all here to help.
Andy

Hi again Andy,

I charged the bike last night as power was lacking on previous rides, then I accelerated to test it and it did not display the orange overload flashing light nor the reduced battery indicators. All lights remain green with no juddering on startup. I'd need to test it out on a proper ride but do you think all is fine or could there still be a problem with the mosfets?

Thanks in advance,

Urbanpuma

 

[Andy-Mat]

Thanks for the videos Andy-Mat, I watched the first one and found it very informative. At this stage, I won't attempt anything as I don't have the tools or knowledge...I'll just watch the other two videos to gain more of an understanding of mosfets.

Aside from that, what confuses me is where to put the multimeter to test my battery life - it's 8 years old. I have a multimeter.

I'll definitely be back with more questions, thank you very much for this.

Different battery connectors need careful use of the probes so as to to not cause a short circuit. ISo cannot answer you as I do not know your actual battery, sorry, but someone here will!
Meter probes with all but the last 2mm of the tip, insulated with Electrician's tape, would be a good idea, always!
regards
Andy

 

[Andy-Mat]

Hi again Andy,

I charged the bike last night as power was lacking on previous rides, then I accelerated to test it and it did not display the orange overload flashing light nor the reduced battery indicators. All lights remain green with no juddering on startup. I'd need to test it out on a proper ride but do you think all is fine or could there still be a problem with the mosfets?

Thanks in advance,

Urbanpuma

Wait up, test it a bit more, sadly, I could not guess what has happened, except that now it sounds as though the MOSFETs are apparently OK, as I have never heard of one repairing itself before!
Maybe a connector is making bad contact somewhere, or damp got into the electronics, and it has now dried out - possibly!
Regards
Andy

 

[UrbanPuma]

Wait up, test it a bit more, sadly, I could not guess what has happened, except that now it sounds as though the MOSFETs are apparently OK, as I have never heard of one repairing itself before!
Maybe a connector is making bad contact somewhere, or damp got into the electronics, and it has now dried out - possibly!
Regards
Andy

Thanks Andy,
Maybe it wasn't the mosfits at all, I suspect loose connection too. Thanks again for your kind help.