De-tune a Bafang CST 500w or possible swap?

Alan Quay

Esteemed Pedelecer
Dec 4, 2012
2,351
1,076
Devon
Has anyone tried using the above motor with a 6 FET controller? I have one kicking about, and it runs fine on the bench with a KU65, but I don't know how it'll be on a bike. I don't require much torque, I'm happy with my other SWX bikes in that regard. But, the next build will be all disk brake and this is the disk one I have.

The other option is to swap it for something 250w with cassette and disk if anyone is interested?
 
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pn_day

Pedelecer
Jul 26, 2013
185
40
St Andrews, Fife
Not quite what you asked, as I've only ever run it with an S12P or an S12S controller, but I have run that motor with a much lower current (removed solder from the shunt) and also used the controller in 'torque control' which just limits the current.

Worked fine. However, I ended up increasing max current, setting controller to speed control and then just set the max speed by changing assist level - it just suited my riding style better.

Just passed 1500 miles on my CST equipped conversion - does the job well.

YMMV! Phil
 
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anotherkiwi

Esteemed Pedelecer
Jan 26, 2015
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The European Union
It should run just fine you are supplying 15 Amps peak which is more than enough to get 500 Watts. Maybe the controller won't enjoy being asked for peak Amps for too long a time?
 

Alan Quay

Esteemed Pedelecer
Dec 4, 2012
2,351
1,076
Devon
Not quite what you asked, as I've only ever run it with an S12P or an S12S controller, but I have run that motor with a much lower current (removed solder from the shunt) and also used the controller in 'torque control' which just limits the current.

Worked fine. However, I ended up increasing max current, setting controller to speed control and then just set the max speed by changing assist level - it just suited my riding style better.

Just passed 1500 miles on my CST equipped conversion - does the job well.

YMMV! Phil
Your right, not what I asked, but exactly what I should have asked. Thanks for the response.

I'm now pretty sure it'll be OK, as the only difference is current. As I say, it runs nice and quiet on the bench so it's only a question of power.

With 6ah of lipo and my newly acquired Carrera Kraken I reckon it'll be just right.
 

Alan Quay

Esteemed Pedelecer
Dec 4, 2012
2,351
1,076
Devon
It should run just fine you are supplying 15 Amps peak which is more than enough to get 500 Watts. Maybe the controller won't enjoy being asked for peak Amps for too long a time?
The KU65 is a 6 FET controller, and is happy up to 15 amps (18-20 if modded).

On the 12 FET Controllers (s12p and s12s) this motor will happily run up to 30A, 1.25kW.

I want to run it at about 4A peak, 168w, where it may stall.

I will report back when I get it on the bike.