Preliminary advice for fitting a Bafang bbs02 motor only

[wheeliepete]

Before you buy any type of controller I would strip and inspect your motor for any other damage or wear that could have caused the failure. The 750w is prone to overheating if thrashed and abused and can also suffer water ingress if ridden in harsh conditions. As this motor has come to you as a non runner, you have no idea of it's condition inside, and a strip and re grease will help avoid furthur disappointment. Lots of helpfull vids on YouTube.
https://www.youtube.com/results?search_query=bafang+bbs02+teardown+

 

[Gully]

Great advice, thanks.

Still wondering about controller power though. So it makes sense that nominal wattage isn't particularly relevant, but still in terms of current do I want to shoot low or high?

BBS02 750W is 25A so I'm wondering if I get a 13A controller, will the motor pull more current and blow the controller? Or does it work the other way around, i.e. if I get a 40A controller will it try to deliver 40A to my motor and burn it out?

Any idea?

Cheers

 

[wheeliepete]

The motor can't pull more power than the controller can give, so a 25 amp one will be fine. Those motors can't really take anymore than that, so I would advise making that the max. If you get one with an LCD, like the KT's, you will be able to lower the amperage to give you better range, depending where you are riding.

 

[harrys]

When you did not have a display. BBS did not run with the jumper hack. Indicates a bad controller.

When you finally get a display, it shows error 30. Confirms there's no controller activity. Suggests the seller was dishonest, as he likely knew all of this.

It's possible that another controller would get it working, but how do you know the bearings aren't ready to fall out?

Best bet is to cut losses and go with another kit. If it is a hub motor, someday you can connect that controller to this BBS02, as you will have more knowledge and see if you can spin it.

 

[Gully]

Thanks guys, thought it would probably be a ≤25A controller.

Does look like dishonest seller, hopefully they didn't know something I don't about the motor! However the eBay seller was 'The Bike Shop Wales'. Seems odd if a reputable bike shop mini-chain would bother selling dodgy second-hand motors through its official eBay account? They agreed to an £80 refund so I can buy a new controller from China. But since money is tighter than I expected this month, I'm considering external controller or else wait until next month to order the proper part.

Think I'll wait until I get a chance to open the motor and check all is well + regrease before I decide.