Bafang BBSxx - fault finding and fixes

[Somebodystopme!!]

I think my controller just crapped out.
When I turn it on it flashes momentarily and then shuts down.
I have contacted both Paul and LeGrand about getting a replacement. Hoping I can get the new 9FET controller.
Less than 1000 miles on this unit.
I love this drive when it works, but Bafang better step up their game.

LeGrand suggested I check the battery connection. Turns out I had a poor connection somewhere in the line. Wired up a new battery cable and the controller is working like it should. No problem with the controller after all.

that's good news. Mine just started doing the same Exact thing! I bought a new kit to install on my Kona Stinky and was just getting ready to hit the track after my last test run when this happened. I'll check my Battery connections and cable. weird electric bugs.

[Somebodystopme!!]

That fixed it, thanks Tesla!

[joshseitz]

I've now changed to a new cassette and chain. It all almost work fine.

The front chain sometime fell off while riding. It happens most of the time when I change gears.

Would that be because the chain isn't properly tensioned?
Or maybe i need some front chain alignment guide?

I too have experienced occasional chain drop on my BBS02, particularly following a rough section or when coming off a jump. I plan to transition to a new short cage Shimano Shadow+ derailleur with the clutch that maintains constant tension on the cage. I could also stand to shorten the chain by a couple of links. I may also add a chain guide up front as well. I'll report if this all amounts to fewer chain drops.

[Somebodystopme!!]

I've now changed to a new cassette and chain. It all almost work fine.

The front chain sometime fell off while riding. It happens most of the time when I change gears.

Would that be because the chain isn't properly tensioned?
Or maybe i need some front chain alignment guide?

I too have experienced occasional chain drop on my BBS02, particularly following a rough section or when coming off a jump. I plan to transition to a new short cage Shimano Shadow+ derailleur with the clutch that maintains constant tension on the cage. I could also stand to shorten the chain by a couple of links. I may also add a chain guide up front as well. I'll report if this all amounts to fewer chain drops.

A chain guide upfront on the sprocket will or should, end those issues for you. They did for me.

[Aushiker]

I am in the process of transferring the motor from one bike to a new one. I have installed the motor and started wiring up it but have struck a problem similar to what teslanv previously reported in this video ...



I am getting a crackling sound coming from the motor, the battery indicator flashes empty on the display and the display shuts down. The connectors are the same as on the original bike which was working but will recheck all that tomorrow just to be sure. Does anyone have any other suggestions or things I should check?

Edit: I have had a play with the multimeter and tested the power cables. With the cable disconnected from the motor I am measuring just over 41v however when I plug the cable into the cable coming from the motor and then push the probes into the back of the connector (Anderson) on the motor side, the voltage reading drops to around 31v. I am pretty sure I am getting a good connection with the multimeter as I can see the metal parts of the connector. Does this sound like a connection problem?

Thanks
Andrew

[cwah]

I'm sick of pedal assist that never do it the way I want.

Is it possible to turn off pedal assist and only have throttle?

[tomjasz]

I'm sick of pedal assist that never do it the way I want.

Is it possible to turn off pedal assist and only have throttle?

Don't pedal. OR. Turn assist to zero and use the throttle. Mine came programmed to run on throttle.

[cwah]

I'm sick of pedal assist that never do it the way I want.

Is it possible to turn off pedal assist and only have throttle?

Don't pedal. OR. Turn assist to zero and use the throttle. Mine came programmed to run on throttle.

When i turn pedal assist to 0 the throttle stops too. In mine throttle is proportional to the level of pedal assist.

I have C963

[tomjasz]

I'm sick of pedal assist that never do it the way I want.

Is it possible to turn off pedal assist and only have throttle?

Don't pedal. OR. Turn assist to zero and use the throttle. Mine came programmed to run on throttle.

When i turn pedal assist to 0 the throttle stops too. In mine throttle is proportional to the level of pedal assist.

I have C963

I'd go to the programming thread and find out what you can change. Sorry, I'm all set up to program but never bothered to change anything since I'm happy with the settings as they are. Someone will give you the answer. Lectric Cycles and EM3ev both ship with full throttle in all settings.

[Mark-az]

Installed 2 BSS02 750w purchased 11/11 with 48v bottle batteries.
The one on my 29in mtb works very nicely. I haven't changed the programming as I have not received the USB to Serial connector yet. SWMBO said my grin was huge when I got back from my first ride.

Of course the 2nd unit, after installation on my SWMBO's bike yesterday, did not work as expected.
After installation and making the battery connections, and lots of zip ties, I pushed the power button to get into the password protected area and the rear wheel immediately spun, very disconcerting. The display stayed blank. I then, foolishly I think now, took the bike out and rode it up and down the block. Pedal assist was evident.
I turned be battery off and on a couple of times hoping there would be something to see on the display, no joy.
Today nothing happens when I pedal.

I haven't seen the behavior described in any of the bafang threads.

The battery checked out at 54v.

I have asked the Aliexpress vendor if I can swap displays between the two; but, I'm not sure what the problem is so I want them to say 'go ahead' as I'm guessing the 2nd controller might be able to fry the good display.

When told of the problem my son said "you haven't given feedback to them, right?". I had to say I have...

Oh, and before we get into the 'full support from trusted vendor' discussion I found this site on 11/11 and hadn't read the bafang and battery threads. I have read some/many of them now; but, there are a whole lot of pages in some of them!

I'll give updates to my progress when I can...
I guess right now I should mount the bottle batteries on both sides of my rear rack so they look like power nacelles!

[brakestad]

Hi Everyone,

I have a problem with my Bafang 250w kit with the C961 display.

The power comes and goes without any error message in the display. It worked fine for a couple of weeks before suddenly the power was gone and I got an error code 07 which is said to be over voltage protection. Then the power came and went for a while until it was permanently gone. After a week it started to work again. Now it mostly works but it happens that the power is lost for a while, but there isn't any error codes in the display.

I have tried with another battery so I have ruled out the battery. Any other that have similar problems? Could it be the wiring to the battery? I haven’t connected the brakes, could that lead to this?

Thanks

[KINNINVIEKID]

Doesn't matter about the brake wires not being used.
Sounds like a problem in your wiring.
Time to get the multimeter out...

[tomjasz]

Hi Everyone,

I have a problem with my Bafang 250w kit with the C961 display.

The power comes and goes without any error message in the display. It worked fine for a couple of weeks before suddenly the power was gone and I got an error code 07 which is said to be over voltage protection. Then the power came and went for a while until it was permanently gone. After a week it started to work again. Now it mostly works but it happens that the power is lost for a while, but there isn't any error codes in the display.

I have tried with another battery so I have ruled out the battery. Any other that have similar problems? Could it be the wiring to the battery? I haven’t connected the brakes, could that lead to this?

Thanks

7 could be motor hall sensor with the C961, by my version of the manual.

http://endless-sphere.com/forums/viewto ... de#p958989

[brakestad]

Thanks for the input.

In my case the throttle doesn't work either when it stops, so then I assume it can’t be the motor hall sensor. Or is that a wrong assumption?

To investigate the wiring I guess I need to wait until it doesn't work? Or can can I get some information from a working system as well.

Some additional information:
Type: BBS01 36V 250w 1408067115

When the power is gone everything looks normal on the display, battery full, no error codes etc. The throttle doesn’t work either.

[Aushiker]

Of course the 2nd unit, after installation on my SWMBO's bike yesterday, did not work as expected.
After installation and making the battery connections, and lots of zip ties, I pushed the power button to get into the password protected area and the rear wheel immediately spun, very disconcerting. The display stayed blank. I then, foolishly I think now, took the bike out and rode it up and down the block. Pedal assist was evident.
I turned be battery off and on a couple of times hoping there would be something to see on the display, no joy.
Today nothing happens when I pedal.

Based on my own experiences and what I learnt so far, I would:

(1) Check any fuses at the battery level;
(2) Check the output voltage from the battery. If okay
(3) Check each connection for correct voltage on the input side AND the output side.

I suspect you have either a blown fuse or a voltage drop at one of your connectors.

Andrew

[CdnE90]

I'm getting the Err 21 on my display (BBS02, 750W), which is according to the manual, is a "speed sensor abnormality". The motor still works, just doesn't show speed and can't change the PAS setting once on the move. This was becoming annoying, so I do the following to remedy:

1. Check to make sure the sensor hasn't moved, and even moved it closer to the magnet on the rim. (still get err 21)
2. Check to make sure the magnet isn't de-magnetized - unlikely, but check anyway. (still get err)
3. Get a replacement sensor, wait forever and pay arm-and-leg for shipping, install it. (still get err)
4. Unclip the sensor wire from the bike frame (was zip-tied on) to check for damage to the wires that could cause shorting. Found nothing.

However.... I did discover that the motor had worked it's way loose in the BB, and was swivelling 10-15 degrees. This was putting strain on the three wires coming out of the main motor housing (battery, control, speed sensor). So now I'm thinking the sensor wires have been pulled out of the controller. I remove the motor, unscrew the cover, and find everything is covered in grey silicone. Can't see anything without removing it, and might cause more problems in the process.

Before I start digging around in the silicone covered controller, has anyone had a similar experience? Is there another likely problem? I might try cutting the existing sensor wires at the motor and try some new ones to see if the wires are the issue.

[mushymelon]

Before I start digging around in the silicone covered controller, has anyone had a similar experience? Is there another likely problem? I might try cutting the existing sensor wires at the motor and try some new ones to see if the wires are the issue.

Use a multimeter and check continuity between the pas sensor plug inside the motor and at the wheel first.

[CdnE90]

Which is the pas sensor plug?

[astmacca]

You could have a look at this thread. He tracked down an error 21 issue.

http://endless-sphere.com/forums/viewto ... 28&t=65281

[mushymelon]

Which is the pas sensor plug?

This one

[CdnE90]

So... update.

I checked continuity between the plug and the wheel sensor. Nothing. So, at this point, it's either the wire has a break in it, or the wire is disconnected from the controller card. I cut the wire a couple of inches from the main motor body (what do I have to lose?) and checked continuity. All good, no breaks. That means there is something broken between the PAS plug and wheel sensor wire.

I take the controller off, and the black wire within the wheel sensor wire bundle slides out freely in my hand. Well, at least I know what the problem is. I dig down through the potting to discover both the red and black are disconnected (can't guarantee that I didn't pull the red off in my digging). Anyway, now I'm stuck trying to figure out which wire goes where. I've attached a zoomed-in picture here. You can see the white wire is still attached, and I think the black wire goes to ground and the red wire goes to the (+) marked spot.

BBS Controller.jpg (165.09 KiB) Viewed 1119 times

[mushymelon]

I have a bare controller ill go take some pics
brb

[mushymelon]

looks like I have a diffent board 9fet 750w

wiring is probably the same.

[astmacca]

Some pics of an unpotted controller on this thread that may be of use??

http://endless-sphere.com/forums/viewto ... =2&t=62983

[Arvicola Terrestris]

hi

crankset broken in my bafang... where i can buy pars crank Right and left?

I have made a separate thread about the bottom bracket and crank on the BBSxx, if anybody has found a repair kit i would like to know more about it.

Everybody is welcome to the thread, especially if you have good knowledge about Thrust ball bearings, which we right now are trying to identify.

http://endless-sphere.com/forums/viewto ... 28&t=65711

/philip