Bought this BBS01 from eBay the other day because it was cheap.

 

I want to test it just to make sure it's working, but I don't know what the polarity of the battery connector is (I presume that's the two pin one at the bottom in the photo..)

 

Would anyone be able to help me figure it out? I could cut into the wiring, but a) even if the wires are red and black I couldn't be sure they didn't just mix up the colours, and b) it would make it more difficult to return if it didn't work

 

I'm thinking I might have to disassemble the housing to follow the wires inside? But I'm worried that would involve disturbing some sealant or something

 

The three pin yellow one is for a sensor, so the three pins will be 5v, signal and ground. The battery connector is two pins, which will be battery positive and ground. You can therefore use a meter set to beep on continuity to test all combinations until you find the two grounds, which will beep. Once you have the battery ground, you know the other is the positive.

The Yellow Julet will be wheel speed sensor. Throttle and brakes are taken care of by the 1-4 trunk cable.

 

 

Opening/removing the controller to trace the wiring for polarity is quite easy, there may be a gasket seal in place but no harm is done by simply refitting.

Edited March 12, 20197 yr by Nealh

Ah yes! Checking the grounds is a great idea, thank you

 

And thanks Nealh, I assumed those were the wire assignments, but it's good to have it confirmed.

 

Assuming it works fine, is there any preventative maintenance I should perform before fitting it to the bike, such as greasing gears or waterproofing? I know the 'B' version was supposed to have improved waterproofing, and I will definitely be using this in some heavy rain.

How to waterproof it.

https://electricbike.com/forum/forum/knowledge-base/motors-and-kits/bbshd/17133-waterproofing-for-bbshd-and-bbs02

 

Everything else you need.

https://www.reddit.com/r/ebikes/wiki/bbs_faq

Oh wow, that's a fantastic resource thank you! Don't know how I didn't find it before

 

One more thing though, which I couldn't find in that faq (although I've only skimmed it atm) - how much resistance should there be when rotating the pedals with the motor off? I read that there is a clutch of some sort between the pedals and the motor, so I thought it should be fairly easy to turn. Maybe not like a proper bb, but similar.

 

But mine is, not exactly stiff, but not loose either. For instance, if turned to horizontal (with no chain attached) gravity is not enough to turn it vertical. There is a fair bit less resistance when pedaling backward however, and gravity is enough to rotate it in this direction.

My BBS01 is rideable on the flat or slight incline with no power but wears me out.

 

But mine is, not exactly stiff, but not loose either. For instance, if turned to horizontal (with no chain attached) gravity is not enough to turn it vertical. There is a fair bit less resistance when pedaling backward however, and gravity is enough to rotate it in this direction.

That's normal, the same as a Bosch CX. It's free when you freewheel.