BBS02 noisy when pedaling with motor off

Sounds like you have a problem with frogs in your motor. My BBS02 is pretty much silent powered. I'll have to try it unpowered. It sounds like there is binding somewhere. Does it make the noise when powered?
 
Doesn't sound all that bad motorwise, though my BBS02 is almost as quiet as a DD hub motor.
Maybe it just needs a bit of grease.
 
No, it is completely new and I already regreased it with Mobilith SHC 100 before even using it.
 
And it is maybe 50 harder to turn the pedals with motor off than on a regular bicycle.
 
Have you overtightened the nut top left in this image?

61bJd6asE4L.jpg
 
I tightened it to 80Nm. That is what Cyberbikes recommends. Luna recommends even more.
Bafang says 60Nm I think, but companies like Cyberbike and Luna say this is not enough to keep the motor in place.
 
Others have obliterated bearings by overtightening that nut on their BBS02:

https://www.pedelecs.co.uk/forum/threads/bafang-reliability-my-experience-overwhlmingly-positive.47333/post-715920

BB characteristics vary by material and design under compression? My BBS01B is secured using the same nut, and on my aluminium framed bike when I overtightened, there was increased motor resistance and noise. I didn't use a torque wrench - slackened it off a touch and it's been fine for over three and a half years. A grunt and 7/8ths as I recall, I don't know what that is in Nm. And no mallet or hammer. No threadlock either. They're not called "Destructions" for nothing.
 
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That nut presses on the BB shell of the frame, if that's somehow affecting your bearings then you had something assembled wrong or broken. Your advice seems to be to just leave it loose, which makes me wonder if you've ever ridden/ worked on a BBSxx bike before. Most people have to tighten that nut with a hammer to keep the motor from rocking back and forth.
Did you read the link you posted? It looks like you were posting there, but the guy who said the bearings were destroyed acknowledged he was wrong on the next page.
 
bengxe said:
That nut presses on the BB shell of the frame, if that's somehow affecting your bearings then you had something assembled wrong or broken. Your advice seems to be to just leave it loose, which makes me wonder if you've ever ridden/ worked on a BBSxx bike before. Most people have to tighten that nut with a hammer to keep the motor from rocking back and forth.
Did you read the link you posted? It looks like you were posting there, but the guy who said the bearings were destroyed acknowledged he was wrong on the next page.
Click to expand...
I didn't say "Leave it loose". And you should read that first and second post you mentioned again. While you're at it, read this post of yours, when the issue was caused by a faulty throttle:

endless-sphere.com

Problem: Bafang BBS01B 250w continues to run after I let throttle off.

Someone gave me a used BBS01B. Apparently it was used for under 1000 miles 4 years ago. If I can get it to work I'll use it (and pay him). I've put it on a frame I'm not currently using. It fits fine. I've rigged it up with the throttle, brakes and head unit (it came with a different head...
endless-sphere.com endless-sphere.com

I certainly hope you have better advice for the OP on this thread. If not, you're going on my "Ignore" list.
 
I just read it again. The guy who is agreeing with the nonsense you're spouting was corrected by someone on the next page, to which he responds "That's does actually make more sense...carry on"
I'm not seeing the connection here to this old BBS01 throttle thread, care to elaborate?

Please feel free to ignore me at any time.
 
bengxe said:
I just read it again. The guy who is agreeing with the nonsense you're spouting was corrected by someone on the next page, to which he responds "That's does actually make more sense...carry on"
I'm not seeing the connection here to this old BBS01 throttle thread, care to elaborate?

Please feel free to ignore me at any time.
Click to expand...

You're ignored.

1723557541842.png
 
hias9 said:
I just removed the nuts and it did not change anything.
Click to expand...
Oh well. Let's hope someone else turns up to suggest something useful.
 
Now I removed the two lock rings inside the axle and this also did not change anything.
 
hias9 said:
Now I removed the two lock rings inside the axle and this also did not change anything.
Click to expand...
Was there anything protuding within the bottom bracket, which needed filing away/flattening before installation? Was it a tight fit?
 
Have you tried it with the original gear cover? It looks to me like you're going to have to swap parts out until the noise goes away. A chain and rear wheel speed input would allow the motor speed to be more consistent.
 
hias9 said:
No, not at all.
Click to expand...
Do you get the range you expect from your battery?

It's really difficult to tell from recordings. Microphones etc. vary quite a lot, compression and EQ could be applied automatically by phones making things sound worse than they are. My own BBS01B is very quiet in operation. I hardly hear it while riding, although it's harder to pedal unpowered than I expected - from what I've read about the BBS02 and BBSHD, that's the norm for the BBSXX(X) series.

If it were my new bought motor, I'd remove the motor, take off the cranks, and do a bench test... and if I was unhappy with the noise, I'd query the seller and possibly raise a return.
 
What do you mean with range? It is new and has never been ridden so far.
Unfortunately seller is Chinese and does not reply.
 
hias9 said:
What do you mean with range? It is new and has never been ridden so far.
Click to expand...
If the motor is physically damaged or in some way faulty, and as a consequence is producing excessive noise and too much motor resistance, I'd expect a reduction in battery range/increase of power use, or overheating over the norm.
 
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hias9 said:
Unfortunately seller is Chinese and does not reply.
Click to expand...
That's another can of worms. I've not yet been able to get a refund from AliExpress. Even if you pay by Paypal you're screwed with some Chinese marketplaces when things go wrong.
 
Unfortunately I have nothing to compare with as the motor is new and has never been ridden so far.
But I would not expect difference in range to be significant because it is running fine.
The problem is increased resistance and noise when pedalling especially with the motor disabled.
 
bengxe said:
That nut presses on the BB shell of the frame, if that's somehow affecting your bearings then you had something assembled wrong or broken.
Click to expand...

Bottom bracket shells are made of metal, and they have elasticity and yield strength. The tighter you squeeze them, the shorter they become. That change in dimension can easily overload bearings and promote failure. I demonstrate the effects of overtightening cartridge bottom bracket lockrings to students in the classes I teach. It's no different with BBSXX except that the forces on the bearings are reversed, outward rather than inward.
 
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