Bafang BBSxx, replacement of bearings in bottom bracket

[astmacca]

Would you share the descriptions when you get it from Paul. I ride in wet and now snow and slush. Thanks!!
Definitely want one in my parts box.

No wukkies. Once done and dusted i'll post exact descriptions of what i ordered with part numbers if i can, but that probably wont be till late Feb.

 

[cwah]

My bbs02 is making strange noise when I'm pedaling. But nothing when I use the motor only.

I suppose I have an issue with the bottom bracket too? I don't think I have the skill to replace the bearing, isn't Bafang supposed to have 2 years warranty on the motor?

 

[Arvicola Terrestris]

Very interesting repair.
Bad needle bearongs, have you checked the crank shaft for wear also?

Dan

God question there!

Yes, there are wear on the left side of the shaft, were the rusty needle bearing was, it's visible. But i don't know yet how much. I'm going to make a roughness test of the shaft surface to find the Ra value, and I will use the right side of the shaft as my reference surface.

/philip

 

[Arvicola Terrestris]

My bbs02 is making strange noise when I'm pedaling. But nothing when I use the motor only.

I suppose I have an issue with the bottom bracket too? I don't think I have the skill to replace the bearing, isn't Bafang supposed to have 2 years warranty on the motor?

If you have the same issue, then you can hear and FEEL it, it's a uneven clicking AND rumbling (in need of a better word).

/philip

 

[Arvicola Terrestris]

Here are some drawings of my plan to modify the bottom bracket and a picture of were the grease nipple will be situated.

 

[cwah]

My bbs02 is making strange noise when I'm pedaling. But nothing when I use the motor only.

I suppose I have an issue with the bottom bracket too? I don't think I have the skill to replace the bearing, isn't Bafang supposed to have 2 years warranty on the motor?

If you have the same issue, then you can hear and FEEL it, it's a uneven clicking AND rumbling (in need of a better word).

/philip

I can feel a click every half turn I pedal. No noise when I'm using the throttle, only when I pedal.

 

[Arvicola Terrestris]

My bbs02 is making strange noise when I'm pedaling. But nothing when I use the motor only.

I suppose I have an issue with the bottom bracket too? I don't think I have the skill to replace the bearing, isn't Bafang supposed to have 2 years warranty on the motor?

If you have the same issue, then you can hear and FEEL it, it's a uneven clicking AND rumbling (in need of a better word).

/philip

I can feel a click every half turn I pedal. No noise when I'm using the throttle, only when I pedal.

Take it apart and investigate, you might find the problem or you might not... :?

A click every half turn can be many things and nothing.

You could also just continue riding your bike, since your not sure if there is an issue at all, and if it gets noticeable worse then you know for sure something is wrong. And if nothing happens the next 5000km then it isn't worth fixing.

/philip

 

[Mara2000]

My bbs02 is making strange noise when I'm pedaling. But nothing when I use the motor only.

I suppose I have an issue with the bottom bracket too? I don't think I have the skill to replace the bearing, isn't Bafang supposed to have 2 years warranty on the motor?

If you have the same issue, then you can hear and FEEL it, it's a uneven clicking AND rumbling (in need of a better word).

/philip

I can feel a click every half turn I pedal. No noise when I'm using the throttle, only when I pedal.

Hi, i have same issue with click every turn of pedal, it appear after cca. 50km from strat of trip. If a tighten the main nut , then clicking disappear but only for say one week, it seems like some backlash in BB ?? :? Problem is that BB has little more diameter than the diameter of motor shaft body - the backlash is aprox. 0,3 mm - so not perfectly fitted and if you peadling strong then there can arise some movements between shaft body and BB tube...

--- sory for my bad english

 

[Arvicola Terrestris]

Hi, i have same issue with click every turn of pedal, it appear after cca. 50km from strat of trip. If a tighten the main nut , then clicking disappear but only for say one week, it seems like some backlash in BB ?? :? Problem is that BB has little more diameter than the diameter of motor shaft body - the backlash is aprox. 0,3 mm - so not perfectly fitted and if you peadling strong then there can arise some movements between shaft body and BB tube...

--- sory for my bad english

Use paper between the Bafang bottom bracket and the bottom bracket shell, I use ordinary newspaper paper, give it some oil or grease before fitting. It will fit perfectly.

/philip

 

[Mara2000]

Hi, i have same issue with click every turn of pedal, it appear after cca. 50km from strat of trip. If a tighten the main nut , then clicking disappear but only for say one week, it seems like some backlash in BB ?? :? Problem is that BB has little more diameter than the diameter of motor shaft body - the backlash is aprox. 0,3 mm - so not perfectly fitted and if you peadling strong then there can arise some movements between shaft body and BB tube...

--- sory for my bad english

Use paper between the Bafang bottom bracket and the bottom bracket shell, I use ordinary newspaper paper, give it some oil or grease before fitting. It will fit perfectly.

/philip

Thanks, but do you think that paper is good choice for long time stability?, what about use thin sheet ...

 

[Arvicola Terrestris]

Hi, i have same issue with click every turn of pedal, it appear after cca. 50km from strat of trip. If a tighten the main nut , then clicking disappear but only for say one week, it seems like some backlash in BB ?? :? Problem is that BB has little more diameter than the diameter of motor shaft body - the backlash is aprox. 0,3 mm - so not perfectly fitted and if you peadling strong then there can arise some movements between shaft body and BB tube...

--- sory for my bad english

Use paper between the Bafang bottom bracket and the bottom bracket shell, I use ordinary newspaper paper, give it some oil or grease before fitting. It will fit perfectly.

/philip

Thanks, but do you think that paper is good choice for long time stability?, what about use thin sheet ...

That's up to you, but it is very reliable if you use it with oil or grease, I've used it many times between shafts and bearings on agriculture machines, and they still run strong after over 10 years and thousand of hours. (Learned it from a mechanic).

/philip

 

[Mara2000]

--- sory for my bad english [/quote]

Use paper between the Bafang bottom bracket and the bottom bracket shell, I use ordinary newspaper paper, give it some oil or grease before fitting. It will fit perfectly.

/philip[/quote]


Thanks, but do you think that paper is good choice for long time stability?, what about use thin sheet ... [/quote]

That's up to you, but it is very reliable if you use it with oil or grease, I've used it many times between shafts and bearings on agriculture machines, and they still run strong after over 10 years and thousand of hours. (Learned it from a mechanic).

/philip[/quote]


Thank you, i check it and will report if the issue solved. :wink:

 

[snowmobile_56308]

Do you have a source for the rubber gasket? I was doing the re-greasing and the gasket ripped and don't know what to use to replace it with. the bearings are still good and are trying to keep the bearings from having to be replaced. don't really have the ability to buy rubber gasket material here so any Ideas on where to buy it would be much appreciated! Also how tight to you tighten those nuts? I tightened the nuts but afraid of tightening them too much.

 

[Arvicola Terrestris]

Do you have a source for the rubber gasket? I was doing the re-greasing and the gasket ripped and don't know what to use to replace it with. the bearings are still good and are trying to keep the bearings from having to be replaced. don't really have the ability to buy rubber gasket material here so any Ideas on where to buy it would be much appreciated! Also how tight to you tighten those nuts? I tightened the nuts but afraid of tightening them too much.

I am getting bearings and gasket from em2ev.com in china, but it should be possible to get it from a EU site mentioned earlier in this thread. As you have seen, the gasket is quite rough made, and it shouldn't be difficult to make a similar one from some gasket material. I'm trying to make a new one in Teflon or PEEK, haven't decided yet.

About tightening the nuts, I don't know yet, but it shouldn't be very tight as the nut goes directly on the Thrust Bearing, I'll return or wait till someone enlighten us.

/philip

 

[Arvicola Terrestris]

Very interesting repair.
Bad needle bearongs, have you checked the crank shaft for wear also?

Dan

God question there!

Yes, there are wear on the left side of the shaft, were the rusty needle bearing was, it's visible. But i don't know yet how much. I'm going to make a roughness test of the shaft surface to find the Ra value, and I will use the right side of the shaft as my reference surface.

/philip

I have the result now, the wear on the left side of the shaft is more and less damaged then anticipated.

The diameter of the shaft is reduced with 6/1000 of a millimeter (right reference side: 16.988mm, Left damaged side: 16.982mm) So thats not a problem.

As the surface roughness goes:
Normally a surface that is rough, means high Ra value, will wear quickly and have higher friction.
I have checked the surface roughness, and it's not so bad theoretically.
The surface roughness on the right reference side is 0.42 μm Ra
The surface roughness on the left damaged side is 1.13 μm Ra
Then I have polished the damaged side and now I get these readings: 0.13 μm Ra and 0.62 μm Ra
(Ra is an average number for the hight of the peaks on the surface).

BUT the problem is that there are a few very deep groves on the surface and the rest is smooth. As seen on scan number four (below) there are areas that are smooth and then some areas that have high peaks, but the average is nice as seen above.

I haven't yet decided what to do, get a new shaft or rely on my greasing project will keep the bearings alive hence the deep grooves.

If I go ahead and keep the shaft, then I could check the state of the bearing in a few month and also see if my homemade seal works. The bearing has arrived at customs in Denmark, so I just need to get them. A new shaft will take several weeks to arrive.

/philip

 

[DAND214]

WOW!
If you need a new one it looks like you could make one yourself.

Dan

 

[Arvicola Terrestris]

Thanks Dan for you thrust in me

The project is moving on, bearings has arrived from UK and China, a grease nipple and some bearing grease is bought in the local tool shop.

I have decided to use the damaged shaft, probably not the wisest decision, but a decision was needed.

So far I have manged to prepare the frame for the grease nipple, mounted the motor and the grease nipple.
Next part is to make a better shaft seal out the PTFE (teflon) I have. And mount the rest of the bearings, washers and nuts.

/philip

 

[tomjasz]

FWIW Cailfornia ebikes, the guys that build the 100MM kits, have 68MM shafts for $12.50.

Nice job o the grease zerk! The OEM bearing that same form China? Cost? (before shipping and fees?)

My confusion. One supplier tells me that INA NK17/16 is a direct replacement. The proprietary is the thrust bearing, which is the combination ball and needle affair?

 

[Arvicola Terrestris]

FWIW Cailfornia ebikes, the guys that build the 100MM kits, have 68MM shafts for $12.50.

Nice job o the grease zerk! The OEM bearing that same form China? Cost? (before shipping and fees?)

My confusion. One supplier tells me that INA NK17/16 is a direct replacement. The proprietary is the thrust bearing, which is the combination ball and needle affair?

The NK17/16 is stock every where. The thrust bearing is impossible to obtain anywhere else then from a BBSxx dealer.

I'm not sure what i paid from Paul at EM3EV, I bought some other parts too. But it is possible to get it from other vendors, maybe California ebikes since they make the shaft conversion, those thrust bearings break easily when dropped.

/philip

 

[snowmobile_56308]

Any other leads on bearings? when I contacted Paul he first asked if I purchased from him and when I told him I did not, he told me that they didn't sell bearings. Tried my seller but has yet to get back to me. any suggestions?

 

[Arvicola Terrestris]

Any other leads on bearings? when I contacted Paul he first asked if I purchased from him and when I told him I did not, he told me that they didn't sell bearings. Tried my seller but has yet to get back to me. any suggestions?

Maybe here:
http://www.bike-emotion.org/pedelec...tzteile-fuer-bbs01/lagerschalen-set-bbs01.php

But they seem to be out of stock, but send them a mail and tell us about it.

 

[tomjasz]

California ebikes has them. Link in my sig. $7.00 for the readily available one, $18 for the OEM and $12.50 for a 68MM shaft.

 

[snowmobile_56308]

Thanks for the lead on the bearings!!! While I am doing the preventative maintainence, I want to track down all of the consumable parts so I can keep the kit running

 

[phiz]

After 1500 miles my left thrust bearing turned into dust. Thanks to this excellent thread I was able to replace them with no issues.

I ordered the thrust bearings from http://www.california-ebike.com. They cost $20.70 each (paypal). I also got new needle bearings from http://www.california-ebike.com since it was open and they were $6.90 each. I tapped them out / in using a 1/2 piece of PVC pipe. Shipping was $10 and it arrived in two days.

The rubber washer is gone, ground into goo. I packed the bottom bracket with waterproof grease and will re-grease it every 1k miles now. I don't think it had much grease (if any) from the factory.

The rest of the unit looked to be in perfect condition with no visible wear.

BBS02 750W
Kona Dew Plus
48V 12ah LiON bottle battery x 2

 

[queenkong]

Hi guys,

To share my experience too. I have taken apart my bbs02 750w a couple of times. 1st, due to clicking sound from the large gear. Opened up and greased the spawn and pawl gears (similar kind as ratchets) and everything's good. Then, thrust bearings had issues. Balls were missing. So I searched everywhere (for some reason missed this thread) and decided to use standard 6803 sealed bearings for bicycles to replace both bearings. Things were working good altho dimensions were very little off. They fited snugly to the shaft too. Everything else fits back well. The only issues I had was the 2 shaft lock nuts couldn't screw as deep as original and I thought shouldn't be a big problem.

Just today, there was noise again. So I took the kit apart and to my shock, the bearing (non drive side) was completely crushed into pieces. The drive side one is perfectly fine. The small pinion metal helical gear connected to the large gear had teeth broken too. I had no idea why man. The other parts are tested to be working perfectly well.

Now I need replacement for the pinion but couldn't find it anywhere.... Although I'm really glad I found this thread and at least know where to try to get the correct bearings....

Anyone knows where I can try my luck for the replacement pinion metal gear?