Repair BBS02 Bottom bracket

[cwah]

Hello all,

My BBS02 has recently developed some noise on the bottom bracket when I am pedaling. It happens every half turn of pedal, and always the same tick.

Motor and throttle are unaffected.

I purchased the kit from BMSbattery, and I've already used my joker (paypal claim) once when my other kit failed. I know they won't help me anymore.

So now, I'm trying to figure out how I can fix it, apparently BBS02 should have 2 years warranty from Bafang, but I'm not sure what value it has?

 

[patpatbut]

Wore pedal also makes click sounds, have you checked it as well?

 

[mechaniker]

the click might be the needlebearing inside the bottom-bracket. The Bafang is easy and cheap to repair even for people with low mechanical skill´s

The value of warranty from bafang or other chinese companys is zero but it dosent matters. All Bafang BBS-part´s or bearing is easy to buy and easy to replace

regards
frank

 

[Kinninvie]

Here is the guide
http://endless-sphere.com/forums/viewtopic.php?f=28&t=65711

 

[cwah]

No it's not the pedal otherwise it would be a quick fix.

I've seen the thread from the guy, it seems to be very time consuming and complicated. I'm not sure I want to go into the repair, buying new parts and diagnosing the problem.

For now it works, but the noise may amplify over time (It already had)

 

[trex]

try to refit the kit. It could be just a small fault, not obvious until you've found it.
The way the motor is hanged could lead it to move slightly and may knock against the downtube with each revolution when you push hard on the pedals. The motor is not totally waterproofed. Put penty of grease on the bottom bracket to stop water getting in.

 

[Geebee]

I seem to recall an internal silicone seal coming adrift and causing a ticking sound on a couple on endless sphere as well, it was an easy fix ie. remove the offending seal.

 

[mechaniker]

... it seems to be very time consuming and complicated. I'm not sure I want to go into the repair, buying new parts and diagnosing the problem.
For now it works, but the noise may amplify over time (It already had)

dessamble of the crank is quite simple, If you want I can make a photosession how to do, at the time I have around 20pcs BBS Motors for repair here so I can describe you the way step by step.

Drive further and waiting isn´t realy an option because if the noise comes from the needlebearing, the crank-axle get´s scretches cause of the friction and then you need to replace the axle. With waiting you do more harm than good

regards
frank

 

[cwah]

If you can share some pictures that would be great as I don't want to break it

Thank you

 

[Nealh]

Out of interest what mileage ahs your bbs done Cwah ?

 

[mechaniker]

hi,
as promised here is the disassemble instruction with a lot of photo´s
If you do it the first time you maybe need something between 15-30minit absolut not more.
I hope it is helpfull to you or others. You can let the motor at the bike, it is´nt neccassary to build the motor out of the bike.

btw, if you reassmble it use grease and the crown-nut only turn up to the point when the axle has no axial-movement. Do not make it strong because then the trust-bearing go damaged.

regards frank

 

[Nealh]

Looks to be a fairly simple fix with good pics to follow, esp worth doing just to regrease/ prevent water ingress and damage before it starts.

 

[cwah]

hi,
as promised here is the disassemble instruction with a lot of photo´s
If you do it the first time you maybe need something between 15-30minit absolut not more.
I hope it is helpfull to you or others. You can let the motor at the bike, it is´nt neccassary to build the motor out of the bike.

btw, if you reassmble it use grease and the crown-nut only turn up to the point when the axle has no axial-movement. Do not make it strong because then the trust-bearing go damaged.

regards frank

wow that's excellent. I wasn't expecting so much details and I'm really grateful for that. I definitely need to open it and see what's wrong. Hopefully I have a spare bike so I'm going to use the spare for now until it's fixed.

 

[cwah]

Out of interest what mileage ahs your bbs done Cwah ?

About 350kms. Not much actually.

 

[Nealh]

As you say Cwah not much at all, mine has now covered 550 miles so a little more but has been faultless but as a precaution will remove and regrease.

 

[trex]

I don't think the noise comes from the needle bearing in cwah's motor.
These bearings are specified for 10,000+ miles. If this goes, the one way clutch would slip a little if you push very hard on the pedals.
His problem comes from somewhere else.
Cwah, you should refit the kit to make sure that the noise comes from the motor and not the crank bolts not tightened enough or knocking between the motor and the downtube (put a rubber sticky pad on the downtube to make sure that's not it).

 

[mechaniker]

....
These bearings are specified for 10,000+ miles...

hi trex,
you´re certainly right if the product would come from europe but if the product comes from China......
I have BBS-Motor´s with just a few km riding and it was neccassary to change the axle and the bearings! I have seen motors with a damage from first day because it was wrong assembling at the factory.
I dont say the noise come from the bearing but after supply of some thousand pieces BBS Motors and repair of many-many BBS-Motors I say it is a weak point on that motor and the clicking every half turn is often come from that bearings.
The bearing is not a bíg deal to check but can save a lot of money.
The freewheel is mostly für the BBS not a problem. The freewheel is a typical hub-motor problem

cheers
frank

 

[trex]

I agree that quality control in Chinese factories is weak but the fact remains that cwah's motor has done about 700kms without problem.
It's only prudent to rule out other factors before jumping to conclusion.
Cwah reported that the noise is once per revolution suggests that the noise is somehow related to pedalling.
For example: does the motor make clicking noises when using the throttle?
If it does, then the insufficiently tightened cranks as a possible cause can be ruled out.

 

[cwah]

Throttle only works perfectly fine, no noise or issue. So it I suppose it wouldn't be a problem with the crank tightening?

How do I open it without this tool?

Or shall I buy one? then where?

 

[trex]

Throttle only works perfectly fine, no noise or issue. So it I suppose it wouldn't be a problem with the crank tightening?

on the contrary. If it works perfectly on throttle then your motor is OK, just refit the cranks. Grease the BB spindle, gently tap the cranks into position with a rubber mallet and do up the crank bolts real tight.