Bafang BBSxx, replacement of bearings in bottom bracket

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Arvicola Terrestris   100 W

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Bafang BBSxx, replacement of bearings in bottom bracket

Post by Arvicola Terrestris » Dec 29 2014 9:02am

I don't think this subject is dealt with elsewhere in here.

I had a friend use my Christiania Cargo Trike for a weekend, what i didn't think about was that since he is a professional sportsman, and his legs is among the strongest i Norway, it only took him 24 hours to break the bearings in the bottom bracket on to of my bicycles. :shock:

So hence the winter it's time to replace theses bearings, the first bike was no problem (normal bicycle). But my cargo trike with a Bafang bbs02 48v 750w is not so straight forward (serial number 1402200287 from March 2014 and has run approx. 4000km).

First I ordered a tool to remove the nut with four slots (10$), the tool didn't fit, so i had to machine it to make it fit (milling machine i think it's called). The tool was made of Kryptonite (probably white cast iron or martensitic steel) so i ruined for 200$ of drill bits. :shock:

If you disassembly the crank, don't expect to be able to assemble it again with the original parts, it can be done, but there is much that can go wrong. The bearings can't be pushed out, they has to be gently hammered out with a mandrel. And before you know of it you have small balls all around you shop, or needle bearings that are damaged.

to be continued...

/philip
Last edited by Arvicola Terrestris on Dec 29 2014 1:31pm, edited 1 time in total.
Christiania cargo trike, Bafang bbs02 750W, 48v, 16s2p LiFePO4 30Ah, 50kg
Grace mxII Urban S, 2. gen. Bosch 350W, 36v, Bosch Powerpack 400 11Ah, 23kg
Trek T420+, BionX PL250 HT, 250W, SRAM 3 speed IGH, 36v LiMn 9,6Ah, 20kg

U.S. Costomary Unit = SI Equivalent:
Length: in. = 25.40mm - ft = 0.3048m - mi = 1.609km
Mass: oz = 28.35g - lb = 0.4536kg
Pressure: psi = 6.895kPa (MPa = N/mm^2)
Velocity: mph = 1.609km/h
Volume: gal = 3.785l

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Arvicola Terrestris   100 W

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by Arvicola Terrestris » Dec 29 2014 9:37am

First remove the pedal arms on both sides and the chain. You can leave the motor on the bike if you like, I did.

Left side first:
Remove the aluminium M33 nut and leave the M33 steel nut (older models have to identical M33 steel nuts, which don't need to be removed)
Remove the the nut with four slots from the crank shaft
Remove rubber seal from the crank shaft
Remove aluminium washer from the crank shaft
Remove last nut with four slots from the crank shaft

Right side:
Remove five small PZ0 screws from the plastic gear cover on the drive unit
Now you can pull the crank shaft out with chain wheel and the large gear

Inside the bottom bracket is now four bearings, 2 Needle bearings and 2 Ball Thrust bearing. One of each, on each side.

Use a mandrel and a small hammer and try get them out gently, for the left side bearings use the mandrel from the right side of the bottom bracket and Visa Versa

Parts of the Ball Thrust Bearing might just fall off, so watch out.

To be continued...

/philip
Attachments
NK 17 16.jpg
Needle Bearing
NK 17 16.jpg (4.85 KiB) Viewed 13868 times
Fushi Thrust bearing.jpg
Ball Thrust Bearing
Fushi Thrust bearing.jpg (54.77 KiB) Viewed 13868 times
IMG_20141229_114048 redigeret.jpg
Right side with crank shaft, gear and bearings removed
IMG_20141229_114048 redigeret.jpg (208.89 KiB) Viewed 13868 times
IMG_20141229_114038 redigeret.jpg
Left side, without crank shaft and bearings
IMG_20141229_114038 redigeret.jpg (124.18 KiB) Viewed 13868 times
Christiania cargo trike, Bafang bbs02 750W, 48v, 16s2p LiFePO4 30Ah, 50kg
Grace mxII Urban S, 2. gen. Bosch 350W, 36v, Bosch Powerpack 400 11Ah, 23kg
Trek T420+, BionX PL250 HT, 250W, SRAM 3 speed IGH, 36v LiMn 9,6Ah, 20kg

U.S. Costomary Unit = SI Equivalent:
Length: in. = 25.40mm - ft = 0.3048m - mi = 1.609km
Mass: oz = 28.35g - lb = 0.4536kg
Pressure: psi = 6.895kPa (MPa = N/mm^2)
Velocity: mph = 1.609km/h
Volume: gal = 3.785l

astmacca   100 W

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by astmacca » Dec 29 2014 9:58am

Your documenting this is very much appreciated.

Can you list the brand name and part numbers of the replacement bearings you are using??
Ian. LabTech for Plant and Marine stuff in Perth W.A.

Bafang 500W/48v on old Apollo MTB.

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Arvicola Terrestris   100 W

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by Arvicola Terrestris » Dec 29 2014 10:23am

Now all is disassembled, and I need some new bearings.

On my bottom bracket the bearings on the left side is ruined, and there was also water and rust inside, so the the bearings would have failed no matter what.

To complete this repair i need to identify these bearings and think of a way to seal the bottom bracket better then this rubber seal that apparently don't work.

The Needle bearing is without inner ring and has the dimension:
The part from Bafang is stamped "NK 17/16 A"
25mm Outside diameter
17mm Inside diameter
16mm Width

This is a standard part you can get many places, ex. here:
http://simplybearings.co.uk/shop/Bearin ... _info.html


The Thrust ball bearing has weird dimensions, doesn't even fit the Imperial system.
The part from Bafang is stamped "FUSHI" see more here: http://www.fushibearing.com/en/productsjt.asp?id=147
25.85mm Outside diameter
17.50mm Inside diameter
7.50mm Width

This Fushi bearing i can't figure out, so if you have an idea off where to get this one, please tell.

/philip
Attachments
IMG_20141229_114620 redigeret.jpg
Parts from the left side of the Crank Shaft
From left to right (or inside out):
Needle bearing
Thrust bearing
Thick slotted nut
Aluminium washer
Rubber seal
Thin slotted nut
IMG_20141229_114620 redigeret.jpg (75.61 KiB) Viewed 13813 times
IMG_20141229_114505 redigeret.jpg
Above parts seen on the Crank Shaft
IMG_20141229_114505 redigeret.jpg (115.54 KiB) Viewed 13813 times
Christiania cargo trike, Bafang bbs02 750W, 48v, 16s2p LiFePO4 30Ah, 50kg
Grace mxII Urban S, 2. gen. Bosch 350W, 36v, Bosch Powerpack 400 11Ah, 23kg
Trek T420+, BionX PL250 HT, 250W, SRAM 3 speed IGH, 36v LiMn 9,6Ah, 20kg

U.S. Costomary Unit = SI Equivalent:
Length: in. = 25.40mm - ft = 0.3048m - mi = 1.609km
Mass: oz = 28.35g - lb = 0.4536kg
Pressure: psi = 6.895kPa (MPa = N/mm^2)
Velocity: mph = 1.609km/h
Volume: gal = 3.785l

astmacca   100 W

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by astmacca » Dec 29 2014 10:47am

This Fushi bearing i can't figure out, so if you have an idea off where to get this one, please tell.
I've emailed the supplier i bought my kit from (Em3ev) who apparently has contacts in the factory seeking info on the bearings. He's pretty good and usually answers email in a couple of days although with this being xmas / new year?? Will post any feedback i get from him.
Ian. LabTech for Plant and Marine stuff in Perth W.A.

Bafang 500W/48v on old Apollo MTB.

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Arvicola Terrestris   100 W

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by Arvicola Terrestris » Dec 29 2014 11:06am

astmacca wrote:
This Fushi bearing i can't figure out, so if you have an idea off where to get this one, please tell.
I've emailed the supplier i bought my kit from (Em3ev) who apparently has contacts in the factory seeking info on the bearings. He's pretty good and usually answers email in a couple of days although with this being xmas / new year?? Will post any feedback i get from him.
Off course, thanks.

I'll also send a request to simplybearing.co.uk

I would really like to find a similar bearing in GOOD quality like FAG or SKF. This is a operation i want to do as rarely as possible.

/philip
Christiania cargo trike, Bafang bbs02 750W, 48v, 16s2p LiFePO4 30Ah, 50kg
Grace mxII Urban S, 2. gen. Bosch 350W, 36v, Bosch Powerpack 400 11Ah, 23kg
Trek T420+, BionX PL250 HT, 250W, SRAM 3 speed IGH, 36v LiMn 9,6Ah, 20kg

U.S. Costomary Unit = SI Equivalent:
Length: in. = 25.40mm - ft = 0.3048m - mi = 1.609km
Mass: oz = 28.35g - lb = 0.4536kg
Pressure: psi = 6.895kPa (MPa = N/mm^2)
Velocity: mph = 1.609km/h
Volume: gal = 3.785l

cwah   10 GW

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by cwah » Dec 29 2014 8:40pm

I hope that will never happen to me. Looks lile a big hassle

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Arvicola Terrestris   100 W

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by Arvicola Terrestris » Dec 30 2014 11:55am

Arvicola Terrestris wrote:
The Thrust ball bearing has weird dimensions, doesn't even fit the Imperial system.
The part from Bafang is stamped "FUSHI" see more here: http://www.fushibearing.com/en/productsjt.asp?id=147
25.85mm Outside diameter
17.50mm Inside diameter
7.50mm Width

This Fushi bearing i can't figure out, so if you have an idea off where to get this one, please tell.

/philip

Today I got answer from simplybearings.co.uk:

"Hello Philip
Thank you for your enquiry.
I have checked with a number of manufacturers and unfortunately I have been unable to source the bearing you require due to its non-standard size.
It may be a part that has been manufactured especially for the application by Fushi, and thus unavailable to us.
You may need to approach the bike manufacturer for replacement parts.
I am sorry we cannot assist you on this occasion.
Best regards
Your Simply Bearings Help Centre Team"

So today I contacted Fushi Bearing by mail.

/philip
Christiania cargo trike, Bafang bbs02 750W, 48v, 16s2p LiFePO4 30Ah, 50kg
Grace mxII Urban S, 2. gen. Bosch 350W, 36v, Bosch Powerpack 400 11Ah, 23kg
Trek T420+, BionX PL250 HT, 250W, SRAM 3 speed IGH, 36v LiMn 9,6Ah, 20kg

U.S. Costomary Unit = SI Equivalent:
Length: in. = 25.40mm - ft = 0.3048m - mi = 1.609km
Mass: oz = 28.35g - lb = 0.4536kg
Pressure: psi = 6.895kPa (MPa = N/mm^2)
Velocity: mph = 1.609km/h
Volume: gal = 3.785l

astmacca   100 W

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Location: Perth, Western Australia

Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by astmacca » Dec 30 2014 10:01pm

Heard back from Paul @ EM3ev. He's pretty good with communicating about this stuff.
Hi Ian,

If you need any parts to repair any part of the BBS02, we should be able to arrange that part from the factory, no matter what it is. So long as it is made clear which parts is required, with a picture, I am sure it can be arranged.

If anything fails within the warranty period, we will provide it for free, but later than that, we may have to charge something.
I've sent him some of the photos you put on this thread and asked if he can track down the bits for pricing.
Ian. LabTech for Plant and Marine stuff in Perth W.A.

Bafang 500W/48v on old Apollo MTB.

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Arvicola Terrestris   100 W

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by Arvicola Terrestris » Dec 31 2014 6:33am

astmacca wrote:Heard back from Paul @ EM3ev. He's pretty good with communicating about this stuff.
Hi Ian,

If you need any parts to repair any part of the BBS02, we should be able to arrange that part from the factory, no matter what it is. So long as it is made clear which parts is required, with a picture, I am sure it can be arranged.

If anything fails within the warranty period, we will provide it for free, but later than that, we may have to charge something.
I've sent him some of the photos you put on this thread and asked if he can track down the bits for pricing.
Great, hope you succeed.

Meanwhile i have been looking at the other parts, to see if they can be obtained as standard engineering parts.

The nuts are NOT standard, It's a M17x1 but the outside diameter is smaller then standard.
The aluminium sealing washer is NOT standard. Inside and outside diameter is not standard.
The Thrust ball bearing is NOT standard.
The Needle bearing IS standard.
The silicone/rubber sealing I don't know yet. I'm thinking of replacing it with something more durable, like a shaft sealing, but they are 6mm thick, 5mm more then this silicone sealing. So now I'm thinking of making a sealing/washer in PTFE (Teflon) with a tight fit.

There must be more bright people out there with ideas to repair and upgrade this crank set on the motor.

/philip
Christiania cargo trike, Bafang bbs02 750W, 48v, 16s2p LiFePO4 30Ah, 50kg
Grace mxII Urban S, 2. gen. Bosch 350W, 36v, Bosch Powerpack 400 11Ah, 23kg
Trek T420+, BionX PL250 HT, 250W, SRAM 3 speed IGH, 36v LiMn 9,6Ah, 20kg

U.S. Costomary Unit = SI Equivalent:
Length: in. = 25.40mm - ft = 0.3048m - mi = 1.609km
Mass: oz = 28.35g - lb = 0.4536kg
Pressure: psi = 6.895kPa (MPa = N/mm^2)
Velocity: mph = 1.609km/h
Volume: gal = 3.785l

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Arvicola Terrestris   100 W

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by Arvicola Terrestris » Jan 03 2015 12:02pm

I got an answar from FUSHI Bearings in China.
Hi Philip,

Yes,this bearing produce by our company,how many you want it?
cause we don't have stock now,if you can order 5000PCS,we can produce it for you.
Well they seems to be nice people, but i don't need 5000 pieces. So I am back to getting the Thrust bearing from some Bafang supplier or find another bearing.

/philip
Christiania cargo trike, Bafang bbs02 750W, 48v, 16s2p LiFePO4 30Ah, 50kg
Grace mxII Urban S, 2. gen. Bosch 350W, 36v, Bosch Powerpack 400 11Ah, 23kg
Trek T420+, BionX PL250 HT, 250W, SRAM 3 speed IGH, 36v LiMn 9,6Ah, 20kg

U.S. Costomary Unit = SI Equivalent:
Length: in. = 25.40mm - ft = 0.3048m - mi = 1.609km
Mass: oz = 28.35g - lb = 0.4536kg
Pressure: psi = 6.895kPa (MPa = N/mm^2)
Velocity: mph = 1.609km/h
Volume: gal = 3.785l

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Arvicola Terrestris   100 W

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Location: Copenhagen - Denmark

Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by Arvicola Terrestris » Jan 03 2015 12:13pm

I may have found a solution.

BUT... only if it is possibly to disassemble the bottom bracket tube from the gear-housing. I have tried to use a wrench, my first thought was that there the parts where threaded together, but with no success.
IMG_20150103_163123 redigeret.jpg
IMG_20150103_163123 redigeret.jpg (214.41 KiB) Viewed 13548 times
IMG_20150103_163137 redigeret.jpg
IMG_20150103_163137 redigeret.jpg (258.09 KiB) Viewed 13548 times
In my opinion the parts should be possible to take apart, but I can't figure out how. Are they welded, soldered (silver) or pressed together?????

If I get them apart, I can turn the bottom bracket in my Lathe to make room for bearing that is both needle and thrust bearing. This bearing is Ø26mm and the original bearings are Ø25mm and Ø25.80mm.

This bearing:
cats.jpg
cats.jpg (46.18 KiB) Viewed 13548 times
s-c-h_nx.jpg
s-c-h_nx.jpg (12.56 KiB) Viewed 13548 times
NX17Z Budget Full Complement Needle Roller Thrust Ball Bearing 17x26x28mm
http://simplybearings.co.uk/shop/p55658 ... _info.html

/philip
Christiania cargo trike, Bafang bbs02 750W, 48v, 16s2p LiFePO4 30Ah, 50kg
Grace mxII Urban S, 2. gen. Bosch 350W, 36v, Bosch Powerpack 400 11Ah, 23kg
Trek T420+, BionX PL250 HT, 250W, SRAM 3 speed IGH, 36v LiMn 9,6Ah, 20kg

U.S. Costomary Unit = SI Equivalent:
Length: in. = 25.40mm - ft = 0.3048m - mi = 1.609km
Mass: oz = 28.35g - lb = 0.4536kg
Pressure: psi = 6.895kPa (MPa = N/mm^2)
Velocity: mph = 1.609km/h
Volume: gal = 3.785l

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mushymelon   1 kW

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by mushymelon » Jan 05 2015 3:21pm

Arvicola Terrestris wrote:I may have found a solution.

BUT... only if it is possibly to disassemble the bottom bracket tube from the gear-housing. I have tried to use a wrench, my first thought was that there the parts where threaded together, but with no success.
IMG_20150103_163123 redigeret.jpg
IMG_20150103_163137 redigeret.jpg
In my opinion the parts should be possible to take apart, but I can't figure out how. Are they welded, soldered (silver) or pressed together?????

If I get them apart, I can turn the bottom bracket in my Lathe to make room for bearing that is both needle and thrust bearing. This bearing is Ø26mm and the original bearings are Ø25mm and Ø25.80mm.

This bearing:
cats.jpg
s-c-h_nx.jpg
NX17Z Budget Full Complement Needle Roller Thrust Ball Bearing 17x26x28mm
http://simplybearings.co.uk/shop/p55658 ... _info.html

/philip
Correct me if I'm wrong but won't a thrust bearing prevent you from freewheeling the crank if its installed in the bb.

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Arvicola Terrestris   100 W

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by Arvicola Terrestris » Jan 05 2015 5:16pm

mushymelon wrote: Correct me if I'm wrong but won't a thrust bearing prevent you from freewheeling the crank if its installed in the bb.
There are different types of Thrust Bearings on the marked, some are as you mention one-way, others are just two plates with small balls in between.

In the Bafang BBSxx it is the latter. The name Thrust refers to the direction the ball bearing can take a load, in this case it's an axial load "Thrust".
A "normal" ball bearing is also called a "radial ball bearing".
ThrustLoads.gif
http://www.fhwa.dot.gov/publications/research/infrastructure/structures/04043/07.cfm
ThrustLoads.gif (22.74 KiB) Viewed 13418 times
/philip
Christiania cargo trike, Bafang bbs02 750W, 48v, 16s2p LiFePO4 30Ah, 50kg
Grace mxII Urban S, 2. gen. Bosch 350W, 36v, Bosch Powerpack 400 11Ah, 23kg
Trek T420+, BionX PL250 HT, 250W, SRAM 3 speed IGH, 36v LiMn 9,6Ah, 20kg

U.S. Costomary Unit = SI Equivalent:
Length: in. = 25.40mm - ft = 0.3048m - mi = 1.609km
Mass: oz = 28.35g - lb = 0.4536kg
Pressure: psi = 6.895kPa (MPa = N/mm^2)
Velocity: mph = 1.609km/h
Volume: gal = 3.785l

astmacca   100 W

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by astmacca » Jan 06 2015 5:12am

Got the below from the ever helpful Paul @ EM3ev. I think i'll order some bits in February sometime (i want to get the extension cable as well to clean up the programming cable i made) so if there is anyone in Perth, Western Australia, who wants to piggyback and share postage give me a call. Once i do order it may take a bit longer than normal as Paul will have to sort parts from the factory but this order will be non-urgent for me. Since those ball bearings seem difficult to source i would like to have a set on hand, although, i suspect living in a dry climate with no snow mine will last pretty well if i re-lube them in another couple of thousand km.
Sorry I am slow responding, I've just returned from my Christmas/New Year holidays and am catching up with my emails.

I don't know the price cost of the bearings, but it is not a great deal I can assure you. We've never had to supply replacements or even had requests for them, so I don't think they are very prone to failure.

Nylon gear with sprag clutch we have the large helical nylon gears in stock, they are a little expensive (ITRO 25USD). I don’t believe it includes any sort of 1 way bearing, but I may be mistaken.
Set of 4 bearings for the BB I guess around 10USD give or take
Any seals needed to be removed and replaced? seals and replacement nuts would come as part of the set
That tool for opening up the BB section? When I opened a motor, it was easy enough to do so using a screwdriver to knock the nuts around and long nose plier. They don’t need to be especially tight.

As I said, we can get any part you want. I think it is unnecessary to buy these when you don’t have an issue and when there are other parts that are far more likely to fail than the bearings in the BB, but if you really want them, I’m sure they can be arranged if you can wait whilst we get the parts from Bafang.

If you can order anything you want that is listed in the section below, then add comments regarding anything not listed, then checkout with request a quote, I can get back with a revised quote. If you don’t want anything listed, just pick something and make a comment at checkout regarding what you do want:

Bafang Motor Parts

Thanks
Paul
Ian. LabTech for Plant and Marine stuff in Perth W.A.

Bafang 500W/48v on old Apollo MTB.

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by Gab » Jan 06 2015 7:38am

Reading this thread confirms what I thought , that in a sacrifice to make it quiet and compact the design is very complicated to repair and even worse the parts are mostly custom made and non standard, making it a nightmare and costly to maintain. This is ok if you only want to do a few hundred kms but if you want to do thousands then this is not the right kit. The GNG LR and AFT cyclone kits maybe noisier but they are lot less complicated and easier and cheaper to service if you want a high mileage and low cost kit long term. i.e Bottom brackets are a common service part of a bike.. they should not be this hard to replace ! well it would make Bafang happy as you just need to buy a whole new motor from them !

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by mushymelon » Jan 06 2015 6:18pm

Arvicola Terrestris wrote:
mushymelon wrote: Correct me if I'm wrong but won't a thrust bearing prevent you from freewheeling the crank if its installed in the bb.
There are different types of Thrust Bearings on the marked, some are as you mention one-way, others are just two plates with small balls in between.

In the Bafang BBSxx it is the latter. The name Thrust refers to the direction the ball bearing can take a load, in this case it's an axial load "Thrust".
A "normal" ball bearing is also called a "radial ball bearing".
ThrustLoads.gif
/philip
Great info Arvi, hope you can source the bearings you need to get up and running.

Mushy

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by Fantomas » Jan 08 2015 10:04am


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Arvicola Terrestris   100 W

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by Arvicola Terrestris » Jan 11 2015 5:05pm

Gab wrote:Reading this thread confirms what I thought , that in a sacrifice to make it quiet and compact the design is very complicated to repair and even worse the parts are mostly custom made and non standard, making it a nightmare and costly to maintain. This is ok if you only want to do a few hundred kms but if you want to do thousands then this is not the right kit. The GNG LR and AFT cyclone kits maybe noisier but they are lot less complicated and easier and cheaper to service if you want a high mileage and low cost kit long term. i.e Bottom brackets are a common service part of a bike.. they should not be this hard to replace ! well it would make Bafang happy as you just need to buy a whole new motor from them !
Your analysis: Bosch, Bion-X, Panasonic, Yamaha etc... isn't for you then.

My analysis: This Bafang drive is more easy to repair then the Bosch and Bion-X system i also have. And it's definitively more easy to obtain repair info for the Bafang bbsxx.

By the way it's not a bottom bracket on a bike, it's the bottom bracket on an e-bike motor, big difference, like it or not. And spare parts are obtainable.

/philip
Christiania cargo trike, Bafang bbs02 750W, 48v, 16s2p LiFePO4 30Ah, 50kg
Grace mxII Urban S, 2. gen. Bosch 350W, 36v, Bosch Powerpack 400 11Ah, 23kg
Trek T420+, BionX PL250 HT, 250W, SRAM 3 speed IGH, 36v LiMn 9,6Ah, 20kg

U.S. Costomary Unit = SI Equivalent:
Length: in. = 25.40mm - ft = 0.3048m - mi = 1.609km
Mass: oz = 28.35g - lb = 0.4536kg
Pressure: psi = 6.895kPa (MPa = N/mm^2)
Velocity: mph = 1.609km/h
Volume: gal = 3.785l

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Arvicola Terrestris   100 W

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by Arvicola Terrestris » Jan 11 2015 5:13pm

astmacca wrote:Got the below from the ever helpful Paul @ EM3ev. I think i'll order some bits in February sometime (i want to get the extension cable as well to clean up the programming cable i made) so if there is anyone in Perth, Western Australia, who wants to piggyback and share postage give me a call. Once i do order it may take a bit longer than normal as Paul will have to sort parts from the factory but this order will be non-urgent for me. Since those ball bearings seem difficult to source i would like to have a set on hand, although, i suspect living in a dry climate with no snow mine will last pretty well if i re-lube them in another couple of thousand km.
Sorry I am slow responding, I've just returned from my Christmas/New Year holidays and am catching up with my emails.

I don't know the price cost of the bearings, but it is not a great deal I can assure you. We've never had to supply replacements or even had requests for them, so I don't think they are very prone to failure.

Nylon gear with sprag clutch we have the large helical nylon gears in stock, they are a little expensive (ITRO 25USD). I don’t believe it includes any sort of 1 way bearing, but I may be mistaken.
Set of 4 bearings for the BB I guess around 10USD give or take
Any seals needed to be removed and replaced? seals and replacement nuts would come as part of the set
That tool for opening up the BB section? When I opened a motor, it was easy enough to do so using a screwdriver to knock the nuts around and long nose plier. They don’t need to be especially tight.

As I said, we can get any part you want. I think it is unnecessary to buy these when you don’t have an issue and when there are other parts that are far more likely to fail than the bearings in the BB, but if you really want them, I’m sure they can be arranged if you can wait whilst we get the parts from Bafang.

If you can order anything you want that is listed in the section below, then add comments regarding anything not listed, then checkout with request a quote, I can get back with a revised quote. If you don’t want anything listed, just pick something and make a comment at checkout regarding what you do want:

Bafang Motor Parts

Thanks
Paul

God work and thanks astmacca

And you got it right with that grease job you are planning. The right side bearings was just fine, but the left side were rusty because of water getting in. So you should plan a service interval at every 5000-15000km depending on how wet your driving conditions is.

/philip
Christiania cargo trike, Bafang bbs02 750W, 48v, 16s2p LiFePO4 30Ah, 50kg
Grace mxII Urban S, 2. gen. Bosch 350W, 36v, Bosch Powerpack 400 11Ah, 23kg
Trek T420+, BionX PL250 HT, 250W, SRAM 3 speed IGH, 36v LiMn 9,6Ah, 20kg

U.S. Costomary Unit = SI Equivalent:
Length: in. = 25.40mm - ft = 0.3048m - mi = 1.609km
Mass: oz = 28.35g - lb = 0.4536kg
Pressure: psi = 6.895kPa (MPa = N/mm^2)
Velocity: mph = 1.609km/h
Volume: gal = 3.785l

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Arvicola Terrestris   100 W

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by Arvicola Terrestris » Jan 11 2015 5:18pm

Fantomas wrote:replacement bearings http://www.bike-emotion.org/pedelec-mot ... -bbs01.php
WOW! :shock:

That's the most complete selection of spare parts for the Bafang crank drive I've ever seen. And in Europe also.

Thanks!

/philip
Christiania cargo trike, Bafang bbs02 750W, 48v, 16s2p LiFePO4 30Ah, 50kg
Grace mxII Urban S, 2. gen. Bosch 350W, 36v, Bosch Powerpack 400 11Ah, 23kg
Trek T420+, BionX PL250 HT, 250W, SRAM 3 speed IGH, 36v LiMn 9,6Ah, 20kg

U.S. Costomary Unit = SI Equivalent:
Length: in. = 25.40mm - ft = 0.3048m - mi = 1.609km
Mass: oz = 28.35g - lb = 0.4536kg
Pressure: psi = 6.895kPa (MPa = N/mm^2)
Velocity: mph = 1.609km/h
Volume: gal = 3.785l

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Arvicola Terrestris   100 W

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Posts: 109
Joined: Apr 26 2014 5:01pm
Location: Copenhagen - Denmark

Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by Arvicola Terrestris » Jan 17 2015 4:26pm

Well Bike-emotion.org didn't have the bearings in stock, so i have ordered the Thrust Bearings from em3ev.com in China.

The Needle Bearings is ordered from simplybearings.co.uk

The Rubber Seal (black in drawing below) and aluminium washer is the only part I plan to modify. I have got hold of some PTFE plastic (Teflon) and will make new shaft sealing from that.

And i will try to make lubrication of the bottom bracket with a grease nipple, more on that if it succeeds.

/philip
Attachments
Crank Shaft Assembly Bafang BBS01-02.jpg
CAD drawing of the crank shaft assembly
Crank Shaft Assembly Bafang BBS01-02.jpg (59.44 KiB) Viewed 13050 times
Christiania cargo trike, Bafang bbs02 750W, 48v, 16s2p LiFePO4 30Ah, 50kg
Grace mxII Urban S, 2. gen. Bosch 350W, 36v, Bosch Powerpack 400 11Ah, 23kg
Trek T420+, BionX PL250 HT, 250W, SRAM 3 speed IGH, 36v LiMn 9,6Ah, 20kg

U.S. Costomary Unit = SI Equivalent:
Length: in. = 25.40mm - ft = 0.3048m - mi = 1.609km
Mass: oz = 28.35g - lb = 0.4536kg
Pressure: psi = 6.895kPa (MPa = N/mm^2)
Velocity: mph = 1.609km/h
Volume: gal = 3.785l

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tomjasz   10 GW

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by tomjasz » Jan 17 2015 11:20pm

USA source $18 shipped


https://www.mrosupply.com/product/14972 ... yo_Bearing
Arvicola Terrestris wrote:Now all is disassembled, and I need some new bearings.

On my bottom bracket the bearings on the left side is ruined, and there was also water and rust inside, so the the bearings would have failed no matter what.

To complete this repair i need to identify these bearings and think of a way to seal the bottom bracket better then this rubber seal that apparently don't work.

The Needle bearing is without inner ring and has the dimension:
The part from Bafang is stamped "NK 17/16 A"
25mm Outside diameter
17mm Inside diameter
16mm Width

This is a standard part you can get many places, ex. here:
http://simplybearings.co.uk/shop/Bearin ... _info.html


The Thrust ball bearing has weird dimensions, doesn't even fit the Imperial system.
The part from Bafang is stamped "FUSHI" see more here: http://www.fushibearing.com/en/productsjt.asp?id=147
25.85mm Outside diameter
17.50mm Inside diameter
7.50mm Width

This Fushi bearing i can't figure out, so if you have an idea off where to get this one, please tell.

/philip
Thanks Justin_le we're here thanks to you. All the best to the mods for their tireless work keeping it on an even keel.

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by tomjasz » Jan 17 2015 11:27pm

astmacca wrote:Got the below from the ever helpful Paul @ EM3ev. I think i'll order some bits in February sometime (i want to get the extension cable as well to clean up the programming cable i made) so if there is anyone in Perth, Western Australia, who wants to piggyback and share postage give me a call. Once i do order it may take a bit longer than normal as Paul will have to sort parts from the factory but this order will be non-urgent for me. Since those ball bearings seem difficult to source i would like to have a set on hand, although, i suspect living in a dry climate with no snow mine will last pretty well if i re-lube them in another couple of thousand km.
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.
Thanks Justin_le we're here thanks to you. All the best to the mods for their tireless work keeping it on an even keel.

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Re: Bafang BBSxx, replacement of bearings in bottom bracket

Post by DAND214 » Jan 18 2015 12:20am

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

Dan

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