Bafang BBSxx - fault finding and fixes

opperpanter said:
I have a problem with a little squeeking sound from my BBS02 750W when turning the pedals very slowly (engine off).

Not sure if you can hear it, but on my mobile phone I can hear the audio clearly:

[youtube]http://www.youtube.com/watch?v=4U_vuqzpTxw[/youtube]

Can't get the youtube link to work, so here it is: https://www.youtube.com/watch?v=4U_vuqzpTxw&feature=youtu.be

Any thoughts? First signs of internal wear?

Never saw a BBS SERIES motor that didn't benefit from lubrication. Consider it basic care.
 
I have a BBS02 750W with the upgraded FET's.

I ordered the programming cable from Lunacycle to see what the settings were on my drive. I had bought the motor off of ebay (kit with display and battery - http://www.ebay.com/itm/Bafang-BBS02-750W-Mid-Drive-Motor-Ebike-Kit-2016-Slim-48V-12Ah-Samsung-Battery/222021063577) and wanted to see if they had done any pre-programming to it.

I have had it since Feburary and it seems to run good, but seemed like it was lacking some power compared to user experiences I have read on the internet. Wanted to see if it was me or if the settings were lower.

I followed all the instructions here - https://electricbike-blog.com/2015/03/17/programming-the-bbs02-without-frying-your-controller-and-losing-your-sanity/

Once I got to the point of plugging in the cable, I got a small spark and couldn't read anything from the controller. I plugged my display (c965 3 button) back in and I get nothing, can't turn on the system, no power at all.

Things I have done:

Swapped batteries (i have a 48V 11.5Ah and a 52V 14Ah shark pack)
Unplugged battery for a few minutes then plugged it back in (both physically removing battery from cradle and unplugging the battery from the motor itself)
tested voltage on batteries, both are good, they both read the voltage they should be reading.

Any ideas what that small spark could have damaged to cause this?
 
I've got a feeling when you connected the programming cable to the controller, you didn't align the connector properly. There should be arrows on both connector plugs.

I believe that the lead that goes to the display carries battery voltage, so it's likely you have blown something in the controller, if you pushed the connectors together not properly aligned.

Some of these programming cables come with a non original Higo connector, which makes proper alignment a little more difficult.

I've had two different cables. The first came with an original Higo connector, and it was impossible to incorrectly align the two plugs, due to better tolerances.
My second cable came with a non standard connector, and I have to be very careful about getting the alignment right, before pushing the connector home.
 
The cable was from Lunacycles and has the exact same connector as the display, it's keyed and can't be connected wrong.
 
Definitely sounds like a short. I think I successfully did exactly the same thing with mine, but with water (inside the display) rather than a programming cable.

And no, there was no bringing it back. I have been working on an arduino replacement which should be (hopefully) ready some time in the future. No more expensive displays.
 
Howdy fellow thinkerers,

I've been experiencing noise from my newly acquired BBS02 from em3ev. It has less than 250km on it so I wasn't expecting it. (Video of noise included in the album)
I'm currently in the process of finding the problem and might need some help doing it.

Picture Album: https://goo.gl/photos/KfggBXd71MSPGrHa7

From disassembly I noticed a single problem, some metal shards coming from a small broken piece of the magnet gear. This might be the source of the problem but not sure. The o-ring seems to be ok so that isn't the problem. From contact with Em3ev they also suggest looking at the crank but I have trouble opening this. The rubber seal seems to be ether very tight or glued to the bearing. Should I risk breaking the seal to open up the crank. Also planning on greasing everything before putting it back together.

Q: Is it normal I can move the magnet gear like shown in the video? It doesn't seem to stay in the 'true' position.
Q: Is it worth damaging the rubber seal to have a look at the crank shaft?

Any other thread I might have missed where I can find info on diagnosing the problem is greatly appreciated.
 
Timbo925 said:
Howdy fellow thinkerers,

I've been experiencing noise from my newly acquired BBS02 from em3ev. It has less than 250km on it so I wasn't expecting it. (Video of noise included in the album)
I'm currently in the process of finding the problem and might need some help doing it.

Picture Album: https://goo.gl/photos/KfggBXd71MSPGrHa7

From disassembly I noticed a single problem, some metal shards coming from a small broken piece of the magnet gear. This might be the source of the problem but not sure. The o-ring seems to be ok so that isn't the problem. From contact with Em3ev they also suggest looking at the crank but I have trouble opening this. The rubber seal seems to be ether very tight or glued to the bearing. Should I risk breaking the seal to open up the crank. Also planning on greasing everything before putting it back together.

Q: Is it normal I can move the magnet gear like shown in the video? It doesn't seem to stay in the 'true' position.
Q: Is it worth damaging the rubber seal to have a look at the crank shaft?

Any other thread I might have missed where I can find info on diagnosing the problem is greatly appreciated.

The motor does that when it is pulled, that is normal. The other bearing, that stabilizes the rotor is in the housing.

I don't think you have an issue with the bb part, maybe leave that for now. Those seals can be removed, without damaging them, if you are careful (unlike the hd seal which is generally trashed if yiu pull it). A small screwdriver, should do it, just be careful.

I'd try just removing the loose bits that you noted, put it back together and see how you go. It seems quite like a bit of magnet came off, and it got chewed up. That doesn't necessarily mean much.

If the problem recurs, we can arrange replacement parts. No problem to arrange them now, but to be honest i think this was isolated incident. Can't say this is a common issue on nearly new motors, it's rather new to be worn out parts

Thanks
Paul, em3ev
 
cell_man said:
The motor does that when it is pulled, that is normal. The other bearing, that stabilizes the rotor is in the housing.

I don't think you have an issue with the bb part, maybe leave that for now. Those seals can be removed, without damaging them, if you are careful (unlike the hd seal which is generally trashed if yiu pull it). A small screwdriver, should do it, just be careful.

I'd try just removing the loose bits that you noted, put it back together and see how you go. It seems quite like a bit of magnet came off, and it got chewed up. That doesn't necessarily mean much.

If the problem recurs, we can arrange replacement parts. No problem to arrange them now, but to be honest i think this was isolated incident. Can't say this is a common issue on nearly new motors, it's rather new to be worn out parts

Thanks
Paul, em3ev

Thanks for the assistance here Paul. I reassembled the unit and again the sound was still present :( I was able to remove the rubber seal and dissembled the crank. From what I can see, everything here is in order, all the barrings are still intact and everything was tight. Added pictures of components.

I made 3 small videos demonstrating the noise in the album (https://goo.gl/photos/KfggBXd71MSPGrHa7). The first one is without the main crank shaft and you can hear the motor + something extra. I used the walking mode so should be turning slow. I'm thinking the rotor isn't centered true for some reason, allowing the rotor to hit the housing around it. This might also explain why a piece of the magnet came off because it has been under stress from the beginning of the motor. I also added extra video with the crank shaft attached to show the noise and an other one to show a little space between the 2 outer gears, tho I'm not sure that's even a problem.

Anything else I can do to find the noise problem?
 
I agree, it does sound like something isn't centred correctly. We did already arrange a replacement motor structure. That should resolve the issue. Do let us know how you get on. Thanks for your patience in working through the issue and providing clear info.
 
cell_man said:
I agree, it does sound like something isn't centred correctly. We did already arrange a replacement motor structure. That should resolve the issue. Do let us know how you get on. Thanks for your patience in working through the issue and providing clear info.

Thanks for the good service so far, really glad I ordered from em3ev instead of some random aliexpress guy.

I'll update with some video again whey I get the replacement parts in, hopefully showing a smooth running motor.
 
You are welcome.

I'm almost sure the replacement motor structure will resolve the issue. Generally when this sort of issue occurs, or when a motor gets a little rattle, it's on an old motor and is due to wear on shaft, where it fits into the bearing. There must be powerful forces on the shaft of the rotor, due to the design of the gear system (single nylon gear), which must put some big sideways forces on the shaft. I suspect the metal used in the shaft is a bit soft and over time, a litle play forms, then the shaft starts spinning inside the bearing. Generally the problem is most apparent at the base of the motor structure, rather than the opposite end.

If the nylon gear is removed, then the motor ran and you still have a rattle, the noise must be coming from the motor structure, rather than the gears.

In your case, something must be off-centre. Unfortunately, I can't think of any way to check for this without some sort of specific tooling, or measuring device, as the rotor and shaft, are only lined up in the stator, once the case is sealed. As the bearing at the base of the motor structure, is much closer to the rotor, than the bearing at the opposite end of the rotor shaft, then logically, any errors there, would be most significant.
 
Iandayen said:
The cable was from Lunacycles and has the exact same connector as the display, it's keyed and can't be connected wrong.
There have been bad cables. Carefully deconstruct and take photos. Note wire colors. There was a case a few months back as well.
 
I have a BBS02 750 watt I have been riding for over a year now just about 3000 miles with very few problems along the way a few connection and wiring problems due to bad connectors. Recently I have an electrical problem I cant figure. When I power it on sometimes I get er 21 though most of the time the monitor shuts down after a few seconds and nothing works. No display no power and the throttle does not work either. I have to disconnect the battery then hit the on/off button to discharge system the hook the batt back up it will power on for a few seconds and then display goes off and nothing. I am thinking is it my battery since I went with a cheap lipo from china 20AH it has been a great ride with little maintenance but now this. Any ideas? I am going to try another power supply to see if it is the batt. I have checked all connections they are all good and clean. I should also mention every time when it shuts down I check voltage at battery connectors and it reads very low then I disconnect the battery by itself and it reads full charge at 54 volts.
 
My BBS02 750w is 1,5 years old and have 5000 km, mostly riding in mountain grasslands and woods under full power. I love my e-bike but had 3 major failures on BBS02:

1. Small metal pinion gear was made of peanutbutter steel - it got deformed after 2000 km. Dealer replaced it, no problems since.
2. At 2500 km motor shaft o-ring fell of shaft, shaft wore down to 7,94 mm (should be 8mm). Grinding sound was produced. I took unit apart, put blue loctitet 248 on shaf and it works well since.
3. At 2700 km big metal gear tightend to clutch with 5 M4 screws. They untigtened from vibrations, i heard grinding sound. . I retightened them with loctite 248 (but i did no degrease, this might have been mistake). Was good for 1000 km, then again i had to retighten, but one screw was broken - it snapped. I retightened with 4 screws, used load of loctite 248 (again no degrease). Grinding came back after 500 km, now 3 screws were broken.

I was looking for solution. I knew it was near impossible to remove snaped screws, so I decided to drill M5 holes. Material is very hard, I broke 3 drills. I managed to drill trough and made new M5 treads. This time I didn't use locitet but bullet proof method: making dent on screws. See pics. I am sure I fixed this issue for good. 8)

I think this is very bad design from Bafang. They should use longer M5 screws + use loctite in factory. :roll: I hope this post helps fellow e-bikers in case of similar problems.
 

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Update on my replacement motor structure from em3ev. They send out the replacement part very fast and arrived withing a day or two.
Took some longer to find the time to install and put some miles on it, but everything runs smooth again!! Also used the included grease, which saved me from hunting for the right white silicone.

If people are interested in the sound difference, you can see the updated album here (https://goo.gl/photos/KfggBXd71MSPGrHa7).
Last two videos show the smooth running motor with only the motor sound like it should. Thanks again to em3ev for the quick help and assistance.
 
Unread postby ginekolog » Tue Oct 11, 2016 5:08 am

My BBS02 750w is 1,5 years old and have 5000 km, mostly riding in mountain grasslands and woods under full power. I love my e-bike but had 3 major failures on BBS02:

1. Small metal pinion gear was made of peanutbutter steel - it got deformed after 2000 km. Dealer replaced it, no problems since.
2. At 2500 km motor shaft o-ring fell of shaft, shaft wore down to 7,94 mm (should be 8mm). Grinding sound was produced. I took unit apart, put blue loctitet 248 on shaf and it works well since.
3. At 2700 km big metal gear tightend to clutch with 5 M4 screws. They untigtened from vibrations, i heard grinding sound. . I retightened them with loctite 248 (but i did no degrease, this might have been mistake). Was good for 1000 km, then again i had to retighten, but one screw was broken - it snapped. I retightened with 4 screws, used load of loctite 248 (again no degrease). Grinding came back after 500 km, now 3 screws were broken.

I was looking for solution. I knew it was near impossible to remove snaped screws, so I decided to drill M5 holes. Material is very hard, I broke 3 drills. I managed to drill trough and made new M5 treads. This time I didn't use locitet but bullet proof method: making dent on screws. See pics. I am sure I fixed this issue for good. 8)

I think this is very bad design from Bafang. They should use longer M5 screws + use loctite in factory. :roll: I hope this post helps fellow e-bikers in case of similar problems.

Wow thanks for the feedback, i always news this was a very complicated design to repair, who has the time knowledge tools and patience to do all this repair work ? This must the most unreliable mid drive in existence if it needs to be full rebuilt every 2500 km.

And so this means it's only quiet for a few hundred Km's to the next part failure ?? cheecky bloke have done 9000 miles(15,000km) on the 2.8kw cyclone kits with the same original motor , in comparison the lower powered bafang 750w needs 6 full rebuilds to last that distance lol
Of course these are made to sell at low cost and not for people who want to do lots of commuter miles.. buyer beware as they say from Bafang cheap Chinese products.
 
jk1 said:
cheecky bloke have done 9000 miles(15,000km) on the 2.8kw cyclone kits with the same original motor

And you believe it? How many controllers and other problems in 9000 miles? ALL mi dives are more maintenance. Period.
 
And you believe it? How many controllers and other problems in 9000 miles? ALL mi dives are more maintenance. Period.

Why wouldn't we believe him he has a build thread on here somewhere ? granted he has the AFT upgraded cyclone, but this goes to show if you spend more and get ceramic bearings and hardened gears how much longer life and less hassels you will get from Any mid drive. if you see on this BBS02 thread like 90% of the failures are bearings and gear related and these are the most difficult to repair.

I agree definitely mid drives are more maintenance than a Hub, so choosing one that is reliable and wears out less is a lot more important than a hub where this is less important, but some mid drives obviously like the Bafang need a lot more time money and repairs then others due to the design and cheap parts, so that initial low Chinese cost doesn't look so cheep any more does it long term if you factor in the time and cost of the ongoing repairs...
 
So you think the few dozen problems and repairs are indicative of the thousands of BBS series motors sold? Wow! You miss the very nature of how forums work. No one, or very few come here to announce their drive is running great. We come here to learn or sort problems. As a result the reports are weighted to highlight the negative. Talk to those of us that repair, support, use, and help other users. The problems are very real, but hardly as bad as you claim. The cyclone controller Is absolutely a weak spot. One of the largest resellers will tell you that. The motor is a beast, but to represent that we can expect 9000 miles without repairs, and expensive repairs, or to think a BBS repair is some difficult, elusive, high tech repair is not only disingenuous, but just simply ignorance. If I were to criticize the BBS series it would be to highlight Bafangs failure to provide a dynamic parts support chain. But that is improving.

Buy the motor that serves your needs, but let's not obfuscate the facts with anecdotal posts. And by all means don't buy a drive you haven't the skill or tools to maintain.
 
You can't compare the life of the cyclone to the AFT cyclone, they have upgraded all the bearings and gears to better materials so it's not a surprise the life is so long, these are the main wearing parts on a brushless motor after all. Also I think they use the Kelly controllers that are also more reliable.

As for the Bafang I agree with other posters on here , bafang may have sold lots of these kits, but I bet its not many that have done more 5000km like this persons experience here that needed 3 major overhauls... this is invaluable experience for others to know this is a low mileage kit or expect to pull it apart for repairs and breakdowns often.
 
BBS02 on 3000 miles+, with only a replacement of the older crappy MOSFET controller, which Bafang acknowledged and redesigned for future units.

I think it's a little marvel of design and technology, and at least Bafang listen to their customers and improve their products from any criticism. I bow down to you Bafang for making my hobby so much fun.
 
tomjasz said:
jk1 said:
cheecky bloke have done 9000 miles(15,000km) on the 2.8kw cyclone kits with the same original motor

And you believe it? How many controllers and other problems in 9000 miles? ALL mi dives are more maintenance. Period.

Yes i have done over 9000 miles on my small AFT kit, so far i have replaced 3 sets of planetary gears at 10 gbp per set, numerous chains and cassettes all 8 speed so cheap again.
ZERO controller issues as its a Kelly.
only thing that took me off riding was an analyst issue.
I am not saying mid drives are less work as they obviously are, but lets give some credit where it is due.
It still runs and pulls like a train at 18s and 40a.
Darren the cheeky one.
 
Hi all. I have BBSHD and keeps coming loose. I even
Torqued to proper setting. It's tight but after riding for day, it gets loose. Anyone else?

It's trek fuel ex7 with 68 mm bottom bracket. I used no spacers at first and then added 1 space to see if worked but neither is working. I even used blue loctite.
 
drew12345 said:
Hi all. I have BBSHD and keeps coming loose. I even
Torqued to proper setting. It's tight but after riding for day, it gets loose. Anyone else?

It's trek fuel ex7 with 68 mm bottom bracket. I used no spacers at first and then added 1 space to see if worked but neither is working. I even used blue loctite.
I'd pull the little triangular plate of and make sure the serrated edges of the plate are digging into the frame. On mine it left clear indentations. I still had it loosen up though after a lot of jumps so I wrapped a hose clamp around the motor and another one perpendicular to it around the frame tube. No problems since.
 
Dogboy1200 said:
drew12345 said:
Hi all. I have BBSHD and keeps coming loose. I even
Torqued to proper setting. It's tight but after riding for day, it gets loose. Anyone else?

It's trek fuel ex7 with 68 mm bottom bracket. I used no spacers at first and then added 1 space to see if worked but neither is working. I even used blue loctite.
I'd pull the little triangular plate of and make sure the serrated edges of the plate are digging into the frame. On mine it left clear indentations. I still had it loosen up though after a lot of jumps so I wrapped a hose clamp around the motor and another one perpendicular to it around the frame tube. No problems since.
You should be able to get the lock ring tight enough for the fixing plate to hold. But if all else fails here's a $20 solution.
http://california-ebike.com/product/bsb-1-bafang-stabilizer-bar-bbs0102-bbshd/

stabilizer-bar-300x300.png
 
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