Unanswered Bike cutting out when battery on 3 bars

[bikemerchant]

I bought this custom made bike 2 days ago
https://www.adverts.ie/other-sports-...nches/25432673

Was close to fully charged, worked well day 1.
Charged for a few hours and today after about 8km it cut out, just after a stop at a shop.

The battery was showing 3 of 4 bars but the voltage started dropping quickly towards zero, it said something like controller/motor error (I can’t exactly remember) and shut itself off.

I stopped, slipped the battery out and back in and the screen would work again, showing 3 of 4 bars. It worked for less than a minute before the screen shutting off again (no error message from here on, just shut straight off).

Repeated this multiple times – it would shut off once the output reached roughly 700w each time.
No noticeable damage to any cables and it has not been exposed to water since I got it.

Charged it fully and no issue on first test - although I expect the same once i drain 20% or so of the battery.
The seller seems genuine, isn't ducking any questions now but can't troubleshoot it.

Can anybody help me?
Feeling pretty down after my new purchase

Advanced settings are:
Lim: 72kmh, DIM 29inches, UNT:0, P1-46, P2-0, P3-0, P4-0, P5-15, C1-2, C2-0, C3-5, C4-0, C5-10, C6-1, C7-1, C8-0, C9-0, C10-N, C11-0, C12-2, C13-5, C14-3, L1-0, L2-0, L3-1, L4-5.

 

[Neeko DeVinchi]

Hey @bikemerchant, hopefully I can help.

If I understand you correctly, the bike cuts out when you push near 700wh?

Did the bike completely switch off or did the display just show an error code?

Please kindly let me know. Subject to your answer, we may be able to resolve the problem fairly easily (and no, you will not need to buy anything further)

 

[Neeko DeVinchi]

On second thought, this video will probably assist you better.
My guess Is the C12 parameter. It needs to be set at 6.
Try that first and see whether it cuts out

 

[bikemerchant]

Thanks - I paid to have the battery rebalanced and it's been fine since then.

2 days ago the controller screen kept turning off, either immediately, or if not as soon as I turned the throttle.

Yesterday I fully charged the battery, multimeter gave a reading of 54.8V, and it worked fine on my usual 13km journey.

Today it broke down again when fully charged (first time I turned the throttle).
The screen gave a reading of 51V after this, but the multimeter gave a very high 55.1V reading.
It worked for a short journey, then I charged it, then it failed for the next journey.

Should I be testing each battery series again to see if it's a battery issue again?

 

[Neeko DeVinchi]

Thanks - I paid to have the battery rebalanced and it's been fine since then.

2 days ago the controller screen kept turning off, either immediately, or if not as soon as I turned the throttle.

Yesterday I fully charged the battery, multimeter gave a reading of 54.8V, and it worked fine on my usual 13km journey.

Today it broke down again when fully charged (first time I turned the throttle).
The screen gave a reading of 51V after this, but the multimeter gave a very high 55.1V reading.
It worked for a short journey, then I charged it, then it failed for the next journey.

Should I be testing each battery series again to see if it's a battery issue again?

The problem isn't the battery (or the cells for that matter). Moreso, the controller is pulling more amps which the BMS on your battery is rated for.

Simply reduce the maximum current in accordance to a 48v battery (like 20amps), and you'll find that the bike with all its features (like the throttle) will work.

I imagine that with your current settings, you are unable to remain in the higher levels of assist for a sustained period of time?
Let me know if you want me to walk you through the parameters of each menu to alter

 

[bikemerchant]

I imagine that with your current settings, you are unable to remain in the higher levels of assist for a sustained period of time?

Nope it has been sporadic in when it fails - usually at the beginning of a journey.
Once I am up and running it doesn't seem to fail (as of the few times I managed to get it up and running for a few hundred metres in the past few days)

Let me know if you want me to walk you through the parameters of each menu to alter

Yes please, would be much appreciated!
Thanks.