Bafang BBSxx - fault finding and fixes

[tomjasz]

While there have been reports of the gears failing, how common is this? Given that several suppliers and repair folks haven't seen this happen with any alarming frequency, is this a lot of noise about a non event? Many of the criticisms came from non users of BBS0x, just well versed eBike builders that saw it as a weak link. I never expected a relatively cheap Chinese mid drive as a candidate for the kind of use the LR drive will get. After all the price point of the BBS is far below the other name brand mid drives on the market. Buy cheap Chinese, get cheap Chinese.

 

[Nathan]

While there have been reports of the gears failing, how common is this?

I think the point many people have been making is that if you do lots of Km's it will have very common gearbox failures that are hard and expensive to repair compared to the cyclone kit which have most wearing parts easily and cheaply accessible. Its probably not common overall as most people don't do that many kms ever ! or it will take them 5 to 10 years to get to 5000km that someone-else using it daily will do in 6 months so it does not suit those high mileage people. Its seems to be a good compact design when it works but very hard and expensive to repair or do lots of Km on hence why i bought a cyclone kit as i plan to do 10,000 km a year.

Also i didn't realise the chainline issues were so bad that you cannot use the first 1-3 gears or you get lots of derailments ? Happy i didn't end up going the BBS02 as i have no chainline issues with 2 usable chainwheels up front as well !

https://endless-sphere.com/forums/viewtopic.php?f=4&t=72975

 

[speedmd]

Chain dropping may be a loose chain issue. I never get them and often using 1st and second off road but my chain is tight. May be a issue with some chain types.

As far as gear failures are concerned, how can anyone say they are expensive to fix if you have not priced the parts. I often wonder how many of these with trouble have had screws come loose and end up lunching the works when they were running them knowing it was badly in need of a check or just run dry for miles and miles while it was screaming for help. Too early to tell what millage to expect realistically from the gears bases on a few abused or unfortunate units.

 

[byebyepetrol]

BBS01 36v / 350w | Error 8

Helping a mate install a BBS01 on a carbon 29er and it's been a battle.
BB was too big so he had to remove material then reform it (carbon/ resin/ bog)
to get it to fit.

Now with that done the motor won't fire up.
Error code 8 : Hall Sensor error.
C965 panel.

Battery is 41v off the charger, leads have been checked and re-checked.

 

[tomjasz]

BBS01 36v / 350w | Error 8

Helping a mate install a BBS01 on a carbon 29er and it's been a battle.
BB was too big so he had to remove material then reform it (carbon/ resin/ bog)
to get it to fit.

Now with that done the motor won't fire up.
Error code 8 : Hall Sensor error.
C965 panel.

Battery is 41v off the charger, leads have been checked and re-checked.

It seems I remember SamD pulling a BBS01 apart and found chaffed wires. I don't remember the error and am looking for the post...

 

[byebyepetrol]

Thanks Tom.
FYI
Motor supplier (emax) offered to replace controller and harness.
Is it easy to swap out controllers? Any pitfalls?

 

[Lurkin]

Easy. Be careful with the wiring and be sure to seal it again with sealant.

Youtube videos are your friend, familiarise yourself with them first.

 

[chazRevo]

I just wanted to chime in on the stripped gears issue. I have about 3700 miles on my bafang 750. 10 months old, daily commuter for a 35 mile round trip. It ran great up until it started getting loud, vibrating, and locked up on one ride home. I tore the motor down, and the small pinion gear was stripped.

Paul fixed it under warranty, but I think frequent tear down and preventive maintenance are required to keep the reduction gears running smoothly.

Just another data point for the gear issues. Maybe they aren't so rare for those of us putting on the miles.

 

[speedmd]

They admitted to supplying softer then spec. small gear shafts I understand. Fortunately they are standing behind their screw up. All of the shafts should be replaced IMO. Had you lubed this at all. I would say based on mine, every 500- 800 miles is minimum mandatory unless you are using some super duper grease and even so they will have worn significantly by then. The grease fitting idea makes sense at these intervals.

 

[tomjasz]

I imagine, as usual, there's no information available on the dates of manufacture for the change to new shafts?

For me THAT is the biggest frustration. The lack of dates marking the changes and upgrades.

 

[speedmd]

I share the frustration and it is not at all unexpected for me. I deal with this all the time with products from there. It is a cultural quality change that is needed and hopefully will be expedited with the slow up in their economy. They need to get to zero defect mentality, sooner rather than later. Not a easy task.

I will measure back lash on mine next time I am in there just to get a better handle on where I am with it.

 

[bono]

chazRevo- thanks for your post! I would be happy if I could do 3,700 miles on the motor. I had the gears replaced three times up to 2,800 miles. Paul agreed to cover this under warranty. I am sure that there is something wrong with my motor as I have been using it very gently. He did not want to arrange for a replacement and suggested that I contact Bafang directly. I was a little bit disappointed about this, as I am pretty sure that the third repair will not last long.

Anyway, I contacted Bafang and I received the replacement. Pretty nice surprise! Now, I installed the old motor and I am thinking about selling the replacement to install e.g. DD Mxus motor when old Bafang dies. I am doing 500-800 miles per month and need a reliable motor for the commute.

Cheers!

 

[ginekolog]

After having to replace my small metal gear on my 2014-08 BBS02 750W (failed after 2000km) now (at 3000km) i observed diffirent sound, that hear like knock on every rotation of motor rotor. It was most obvious when i rotated big chain ring backwards (with hand).

I opened motor up and my suspisions where correct: magngled orange O-ring on motor shaft (non-gear side). My unit has o-ring groove but it still failed. Measurment said shaft is now only 7,95 mm (instead of 8,00)

I followed keplers advice, loctited shaft to bearing and so far-so good, unit works quiet again. It took me ~3 hours to repair as i also had insulation on wired broken so had to install new insulation.

It seems i had bad luck with CHINA Quality control as i got 2 serial errors in my unit.. jackpot

Well I am still enyoing it every day, going fast on road or going on hiking trails in steep woods 8)

Big thanks to everyone who contributed on ES, helped me a lot

 

[Strum129]

Hi,

I have a problem with my bbs02. I hope I can add it this thread cause it seems to be a collection of trouble shooting posts.

I cant turn the unit on:

I had the unit powered and then I plugged my display into the green connector. I kind of did it on an angle and I bent one of the pins in the green plug. Then I took my house key and put it in there to straighten the pin back....but there was power in the unit and it sparked when I accidentally touched my keys on two pins.

Now I cant even turn the unit on.

The pin is straight now, a bit tarnished on the end, but its the same length as the other pins so i assume its making a connection to the display. but when its all connected and powered I cant turn the display on.

the battery seems fine and a multimeter can detect the full volts up through to the same pins in the green plug.

Could I have blown the controller doing this? is it common for a blown controller to be represented by not been able to turn the system on? or can you turn the system on with a blown controller but just run the motor

any help would be appreciated.

/jim

 

[speedmd]

Could I have blown the controller doing this? is it common for a blown controller to be represented by not been able to turn the system on? or can you turn the system on with a blown controller but just run the motor any help would be appreciated.
/jim

Hi Jim

You could have damaged the controller, the throttle and speed sensor possibly. Most likely the controller. Hard to say not knowing which pins touched.

 

[Strum129]

Hard to say not knowing which pins touched.

If you are looking at the 6 pins and the 'plastic allignment nob thing' is at the top, then it would have been pin 1 and 2 to the left of the alignment noby thing.

I can see a controller is fairly easy to replace, but the throttle and speed sensors, are they apart of the controller if I get a replacement controller? or a separate part of the motor.

edit....or maybe it was 2 and 3 from the same orientation. and THANKS for your help also.

 

[speedmd]

I pinched the main wire on mine when it fell over onto some equipment and it fried comm links in the controller and the throttle. Throttle is easy enough to check with a 5 v supply. It will run without the speed sensor I believe. Power side of the controller should be fine, but not sure how you check the comm side. Mine ran full speed with pas only with a bad (open) throttle. Showed com error on the display. You may have flashed the programming. Just a guess. All the parts are separate.

 

[Strum129]

Hi,

Update.

I got a new controller. Plugged it up and have some mixed results.

I got power back to the display, yay, and the motor runs fine now. However both the throttle and the cut off brakes dont work.

Is there another electric part which governs these features?

Anything else i can try fixing?

Thoughts
Jim

 

[Supafly]

Greetings!

I am a recent e-bike convert (50kms total under my belt) due to this:

My first ever velocipede build. It's a weird looking, yet greatly fulfilling experience (folds too).

Just 50 kms into its life the motor starts making this rattly noise:
https://vid.me/XwO5

I have not abused the motor at all, maybe a few mistaken gears at low speed (full PAS) but nothing absurdly abrupt.

To anyone that may have experience with this issue; before I tear into it, what spares should I have on hand?

Drive serial: 1506022837
Manufacture date: 2 July 2015
Drive type: BBS02 48V 750W
Purchased from this store: http://www.aliexpress.com/store/705369

All the best
Sup

 

[tomjasz]

Purchased from?

Date of manufacture? Serial numbers on controller and motor?

Warranty coverage available?

Sounds like failed bearings to me. Not to common but it has been reported. Bafang covered the warranty for Bono as it's covered for at least one year.

 

[Supafly]

Thanks for the reply. I updated my original post.
I have been in contact with the seller, who claimed Bafang no longer produce this model and has since not replied to further inquiry.
Do you know if the bearings available for purchase, or are they proprietary?

 

[speedmd]

That is what a terrible dealer would tell you. Report them to ali.

All relatively common stuff in terms of bearings. Sounds like a bad secondary gear train to me. Definitely a tear down to see before it leaves you stranded.

 

[tomjasz]

Thanks for the reply. I updated my original post.
I have been in contact with the seller, who claimed Bafang no longer produce this model and has since not replied to further inquiry.
Do you know if the bearings available for purchase, or are they proprietary?

Go direct to Bafang. They have come through for others. Yes the bearings are available. I keep a set in my spares box.

That SHOULD be the latest version. Definitely should be covered by Bafang if the seller and Aliexpress won't come through.

 

[Lurkin]

The seller just wants to avoid covering the cost of repair. This unfortunately isn't unheard of with less scrupulous dealers.

Given the sound can be heard with throttle only, it's not a crank area bearing.

Use the process of elimination to determine what bearing has failed.
i.e. remove the chain, use throttle only.
then take apart the motor piece by piece, spinning the motor before removing another piece. once the sound disappears, its in that piece.

Its up to you whether you attempt to go though Bafang or not, I have had success when contacting Bafang direct, but note the email was answered by the marketing department rather than a technical service or warranty area - it helps to send them video and pictures as English was not a first language. I think I also sent my message in both English and in Mandarin using Google Translate - this might also be an idea. It's one of those things where providing more info/communication methods is a really good idea if you actually want a good response back.

The bearings can be obtained from a decent dealer, Em3ev comes to mind. From memory they are proprietary, so not much point looking for them from a non dealer source (someone else is welcome to correct me here). If you want to save time or just get it done, I would be contacting Paul from Em3ev. This route is likely to be more expensive, but also more likely to work.

Did you pay with Paypal? if its within the time threshold, you could also have a claim against the seller there for selling you a dud? food for thought. A partial claim against them could cover the repair cost?

 

[tomjasz]

One bearing is proprietary, the other not. Make sure you buy a new seal as well. I'm guessing from the picture you're down under? SamD might have some parts sourcing advice if that's the case. Maybe we can roust Bono and get him to add some advice on Bafang relations.