Motor cuts under load

[anon4]

I'm in the process of changing the controller on my Vulcan e spec to hopefully derestrict it. When testing the throttle spins the wheel fine off the floor but when riding it keeps stopping and I cant get it up to speed. Bad connection?

 

[wheeliepete]

Yes, sounds like it could be a bad connection breaking down when the motor is under load. What controller are you using?

 

[anon4]

Yes, sounds like it could be a bad connection breaking down when the motor is under load. What controller are you using?

It's just a cheapo violamart one I had lying around, has the basic throttle with battery indicator. This is not the final one im going to use just using it for tests

 

[anon4]

Found out that with the limiter loop plugged in it doesn't cut out if that helps narrow it down

 

[peter.c]

Is it drawing to much current and cutting out or overheating or sag ?

 

[anon4]

Is it drawing to much current and cutting out or overheating or sag ?

It seems to reach a certain rpm and just stops with a slight judder. Cant find any obvious connection flaws.

 

[peter.c]

That sounds like a form of protection cut out speed or thermal hard to tell with remote diagnosis try a pic someone might notice or try asking woosh he has various controllers and different wheels is this on the suntour rear wheel still ?

 

[wheeliepete]

Your problem could be the battery/BMS not permitting the required current the controller is requiring, which is why I asked earlier about it. The battery is part of the suntour system and may not be able to run a 3rd party controller. What amp rating is the controller?

 

[anon4]

Your problem could be the battery/BMS not permitting the required current the controller is requiring, which is why I asked earlier about it. The battery is part of the suntour system and may not be able to run a 3rd party controller. What amp rating is the controller?

15a

 

[anon4]

Also the battery doesn't shut off which it normally would if BMS was involved

 

[anon4]

That sounds like a form of protection cut out speed or thermal hard to tell with remote diagnosis try a pic someone might notice or try asking woosh he has various controllers and different wheels is this on the suntour rear wheel still ?

Yes still suntour wheel maybe they have thought of this hack haha

 

[anon4]

That said it spins fast unloaded so doubt it

 

[anon4]

I have a Chinese battery will test that now

 

[wheeliepete]

Also the battery doesn't shut off which it normally would if BMS was involved

Yes, but that's OK if it's a generic type BMS, which I doubt it is. These closed system developers like to make things over complicated, and they do!! This is a defunct BMS I pulled from a Bosch battery. Nothing remotely generic or simple about this baby.

 

[peter.c]

are the sensor wires connected I wonder if the output is awkward and not standard , to tie it to them and make it tamper proof remember the new rules eu will force all the suppliers to do this

 

[anon4]

Have tested the Chinese battery and can confirm that actually is the culprit. The good news is the suntour motor is very fast. The bad news is how the hell do I disable/modify the BMS?

 

[anon4]

The controller I've ordered to finish it is 13a. My partner's is also 13a. I will test that hopefully it works, if not I need to stop the BMS cutting out, what a headache

 

[peter.c]

In depth attempt to keep it all in house they call it a closed system and use it as a sales pitch like some other manufacturer is there an extra cable from the controller or just the thick power cables or is it a multi core if the battery has to change as well as the controller and display

 

[anon4]

In depth attempt to keep it all in house they call it a closed system and use it as a sales pitch like some other manufacturer is there an extra cable from the controller or just the thick power cables or is it a multi core if the battery has to change as well as the controller and display

On the original controller there are 2 thick leads and 3 thinner ones. The battery fires up a Chinese controller with just the 2 thick ones but we have this problem under high current. I've just read a spec sheet on the phlyion battery and it states 19a max so the controller should be working unless it's pulling more than its supposed to. I could always ditch it for a hailing or something, but that costs money I don't have

 

[peter.c]

By a fluke or just luck I went for a bafang mid drive but the garage has a front drive 29er front wheel kit that I will never use and the pain of spending more money to sell my over size battery mistake in the Carrera build just to get the card under control