Bafang BBSxx - fault finding and fixes

jateureka said:
Kepler, do you know what date code BBS02 had the O-ring groove?

Is this O-ring issue just with the BBS02 or did it happen on early BBS01 versions as well?

Great info!
Click to expand...

Unfortunately I can't give you a definitive answer on this one. Date on mine is 2/12/2013 and definitely didn't have an O ring on the non drive side. It was also marked BBS01 48V 750W

I have new drive in stock which is marked BBS02 48V 750W and the date of manufacture is 27/02/2014. I haven't opened it up though to check the O ring. The rotor I have pictured is a spare part that I managed to get through my supplier to replace my worn one. However, the original rotor is still in my drive with the shaft loctited to the bearing and running as quiet as the day I installed it.

Just on the parts replacement issue.

Although Bafang do need a bit of prodding, if you can put together a convincing case about the failure including photos and a logical explanation, there is a good chance you will get the part replaced. We have had one local case whereby a stator burnt out. The failure was clearly a manufacturing fault which we demonstrated with good photographic evidence. Bafang came to the party with the the help of the supplier (Amy) and sent out a replacement stator assembly. This dive has been work perfectly ever since.
 
Rotor Shaft installed with Loctite into the stator bearing. I also got the nylon & steel helical gears greased with sil-glyde and reassembled. Tested the drive with just this half assembled and the clicking is gone. - So that is promising. :)

Now on to reinstalling the crank shaft & final gear, however I noticed that the roller & ball bearings in the crank shaft have a clear grease. - perhaps a third type that Bafang used.

Any thoughts on what this clear grease should be? - Silicone based or otherwise?

I am almost there, I just don't want any fatal mis-steps.

Thanks.
 
I just use the same grease as what I use on the metal gears.

In relation to re assembling the crank section, make sure you don't over tighten this.

I use the following method:

With the shaft and thrust bearing installed, fit the silicon seal, shim, then the two nuts. Screw the first nut down very lightly so it just takes out the end play on the crank. Then screw the second nut on and tighten until you feel the crank just start to bind. Then go back just lightly (both nuts should turn together) so that the crank turns freely.
 
Happy to report that my BBS02 is now back on my bike and quiet as the day it was new. Many thanks to Kepler for steering me in the right direction.
For the record, I used the following grease:
@ nylon & steel helical bearings - sil- glyde. http://www.amazon.com/SILGLYDE-LUBE...UTF8&qid=1397698406&sr=8-1&keywords=sil+glyde
@ crank shaft roller & ball bearings - Buzzy's Slick Honey http://www.amazon.com/Buzzys-Slick-...8&qid=1397698491&sr=8-2&keywords=honey+grease
@ final straight cut gears - standard dark gray Moly grease
 
Teslanv are you sure that clicking sound wasnt just the freewheel mechanism in the unit and maybe the added grease fromt eh tear down was the fix? Maybe the O-ring was coincidence? Reason why i question is my unit it 300klm old and is making a faint click when applying power and not pedalling just like in your video. I am hoping its simple as grease wearing off the free wheel.
 
teslanv said:
Happy to report that my BBS02 is now back on my bike and quiet as the day it was new. Many thanks to Kepler for steering me in the right direction.
For the record, I used the following grease:
@ nylon & steel helical bearings - sil- glyde. http://www.amazon.com/SILGLYDE-LUBE...UTF8&qid=1397698406&sr=8-1&keywords=sil+glyde
@ crank shaft roller & ball bearings - Buzzy's Slick Honey http://www.amazon.com/Buzzys-Slick-...8&qid=1397698491&sr=8-2&keywords=honey+grease
@ final straight cut gears - standard dark gray Moly grease
Click to expand...

Great news. Glad I could help.

Kuruchi,

Try the easy stuff first. Hopefully it sorts your problem out.
 
Copied from main thread.........

HELP!!..................The story of my life..."If it can happen..It will happen to me!". As time permitted I have been installing the Bafang crank drive and my battery packs. Due to several other projects going on like painting the house. my bike project have been dragged out a bit. I thought I would finally escape for a few hours last week but I had problems with my derailleur and decided to take my "Old Blue" instead.

This morning I finally got to take it off the stand and actually go for a ride. First impression was "WOW, this puppy is really quite!". I had it set for 9 speeds and was clicked into #9 and using the throttle only. Everything was going great. Starting out in high gear (in error) on the derailleur (14t) it climbed smoothly to 20+ MPH using only the motor on flat ground. At the end of the block I pressed the rear brake lever and released the throttle to turn around. The motor stopped and I coasted through a 180 and hit the throttle again but got no response, no noise, nothing, just totally dead. So I peddled home and checked all the connections and of course the brake levers. Nothing is loose or sticking that I can find. And the temp is in the 50s today so the motor felt very cool. What I did notice is when I hit the throttle I can hear a slight click from the motor. Just one single click each time I activate the throttle. To get another click I have to release the throttle and reactivate it again. But with ether brake lever activated there was no click when I activate the throttle.

Please note that while on the stand for the past few weeks I have test run the motor at least 100 times and used both brake levers many times and never had a problem. So it's hard to imagine the brake lever being the problem. But it is strange that the problem started when I hit the brake. But what about the clicking sound? The screen is working normally too.

It's very hard to believe this drive is damaged already (1 block). Even if I did start out in the wrong gear. Max load on the motor weather caused by using the wrong gear or climbing a steep hill is the same thing. A max load is still a max load. And it was only 1 block and the motor showed no indication of a problem. Strange the problem occurred only after I let off the throttle and then reapplied throttle again.

Any thoughts, wisdom or comments would be greatly appreciated right about now.

BTW, This is the new version of the 750w with a 20a controller (built in March of 2014) and a C961 screen.

Bob
 
dumbass said:
The motor stopped and I coasted through a 180 and hit the throttle again but got no response, no noise, nothing, just totally dead. So I peddled home and checked all the connections and of course the brake levers. Nothing is loose or sticking that I can find. And the temp is in the 50s today so the motor felt very cool. What I did notice is when I hit the throttle I can hear a slight click from the motor. Just one single click each time I activate the throttle. To get another click I have to release the throttle and reactivate it again. But with ether brake lever activated there was no click when I activate the throttle....

It's very hard to believe this drive is damaged already (1 block). Even if I did start out in the wrong gear. Max load on the motor weather caused by using the wrong gear or climbing a steep hill is the same thing. A max load is still a max load. And it was only 1 block and the motor showed no indication of a problem. Strange the problem occurred only after I let off the throttle and then reapplied throttle again. Bob
Click to expand...

With those symptoms, and especially the lack of mechanical activity, I would not be looking for anything related to mechanical failure straight away. In fact I wouldn't even be looking at the motor unit itself to begin with. My Bafang 250 will easily go everywhere around here (no big hills) in top (highest) gear and that's with a 56T ring! So a 750W will not have any problems with loads entailed in going up and down the street, top gear or not!

Given there's complete silence/inactivity with the e-brake pulled on and just a slight motor 'click' when it's released I would be looking first for an electrical problem and probably one peripheral to the main unit:
1. in the main power supply to the motor casing (battery to motor)
2. in the operation of the throttle
3. maybe then in the operation of the controller.

Maybe you've got crook connectors. Or a bung throttle. These are relatively cheaply made parts (the throttle anyway). There are probably a bunch of simple diagnostic routines that you can try to sort out where the issue is located. I'll leave further suggestions to the engineering types on the list! However I would suggest that you not lose confidence in the drive itself because it seems to be generally shaping up as a reasonably strong and well made unit.

Savvas
 
Savvas, Thanks for the reply and yes I agree. I think the unit as a whole is very well designed and thought out. But as you said, some of the parts are cheaply made. The problem is getting those parts needing replacement. I have contacted the supplier and he agreed I should try to make a repair and he would try to get the needed parts for me. Key word here is "TRY".

I am a mechanical person by nature (mechanical engineer) but my electronic skills are in the dark ages. But I do agree it is more likely an electrical problem then a mechanical one. Especially considering I was running the stock crank sprocket that came with the kit and my top gear is only a 14t. It's hard to imagine this motor having a problem pulling very hard.

I hope to get it back on the bench today. I was thinking this morning, it had just stopped raining when I went for my 1 block test ride. I wonder if water could have gotten into one of the connections. They are well sealed but maybe possible.

Bob
 
Update: I disassembled most of the unit and mechanically everything turns freely and all gears including the plastic gear look like new (as they should...they are!). The only thing I have found so far is one of the 3 main wires crossing between 2 sections of the housing are damaged. One wire (yellow) has a large bare spot on it right where it goes through the metal housing. I do not think this is the problem though because there is a rubber bushing in the housing that I think was protecting it. However, eventually this may have shorted to the housing so I'm glad I found it. So the hunt continues. The hard part as anyone who has had to fix one of these is there's no real manual or even somewhere to get spare parts. If nothing else if you have some spare parts you can just change them out till you find a fix. Right now I'm guessing it's not inside the motor it's self (unless I created a new problem taking it apart. :x

Bob
 
dumbass said:
Update: The only thing I have found so far is one of the 3 main wires crossing between 2 sections of the housing are damaged. One wire (yellow) has a large bare spot on it right where it goes through the metal housing. I do not think this is the problem though because there is a rubber bushing in the housing that I think was protecting it. However, eventually this may have shorted to the housing so I'm glad I found it. ...
Click to expand...

As I've said, I've sure the E-engineers on ES will have something more useful to say re diagnostics etc than I. Kepler? Teslanev? At this stage I'd be taking pictures of that damaged wire and sending them to whoever you bought the unit from. There shouldn't be such damage inside! Sounds like either pre-sale damage or poor assembly...

I was going to initially suggest that your description of the problem sounded to me like a motor that was getting insufficient current to fire up and get moving, hence my suggestion that you check all the peripherals for correct function and connections. But your reporting of a damaged/bare wire inside suggests that input from someone familiar with the electronics may be worthwhile. In any case it seems likely (to me) to be a warranty/replacement issue rather than a repair.

Savvas.
 
As I've said, I've sure the E-engineers on ES will have something more useful to say re diagnostics etc than I. Kepler? Teslanev? At this stage I'd be taking pictures of that damaged wire and sending them to whoever you bought the unit from. There shouldn't be such damage inside! Sounds like either pre-sale damage or poor assembly...

I was going to initially suggest that your description of the problem sounded to me like a motor that was getting insufficient current to fire up and get moving, hence my suggestion that you check all the peripherals for correct function and connections. But your reporting of a damaged/bare wire inside suggests that input from someone familiar with the electronics may be worthwhile. In any case it seems likely (to me) to be a warranty/replacement issue rather than a repair.

Savvas.[/quote]

I sent a PM to Kepler just in case he didn't read my posting.

I wish I could blame the wire damage on the manufacture but to be honest I think I may have cased it while disassembling. After getting the back half of the motor off I can see I must have stressed the wire causing the insulation to tear. I think it will be ok if I put some shrink tubing on it though.

Now that I know there's no mechanical damage I think the best thing is to repair the wire and put the motor back together. Then as you say try to find a problem in the peripherals. As we know there are 3 ways to activate to motor; 1) peddle and let the pas kick in, 2) the throttle and 3) hold the "-". I know the motor gives one click when using the throttle and the "-" but haven't tried the pas. I could be wrong but to me this is an indication that the wiring, throttle and button set are all good. It's making me think the problem is in the controller. It's getting the signal but not doing anything with it. Again, I have the 48v, 750w 20a controller. Not to sure how much the warranty is going to do for me because of the seller I bought from. EBay with a 14 day return policy. But I did contact him and he said he would "try" to get any parts I need. I could try to put in a claim with EBay I guess.

Bob

DamagedWire_zpsb26d2396.jpg


gearampDamagedwire_zpsd2af1212.jpg
 
If that phase wire has shorted to the casing, you would most likely have blown controller FET. Hopefully that's not the case so insulate the wires and re assemble and see what it does.

If it still does the same thing, I think you may need to replace the controller.
 
Kepler said:
If that phase wire has shorted to the casing, you would most likely have blown controller FET. Hopefully that's not the case so insulate the wires and re assemble and see what it does.

If it still does the same thing, I think you may need to replace the controller.
Click to expand...

Thanks, I'll be reassembling the motor this weekend and reinstall on the bike and update what happens.

Bob
 
With a bit of luck, the grommet where the wire goes through would have protected the phase from going down to Gnd. Also the wire strands should be individually insulated being the tails from the windings. Perhaps the phase plug was not securely connected. There is still hope. :)
 
speedmd said:
After only a short ride last night mine stopped working. Display is still working but no motor at all and no error messages. Easy riding in slightly wet grass. Lots to learn. Handle switch failure/ troubleshooting/ throttle/ controller reprogram/ reset/ replacement?
Click to expand...

Exactly the same problem I'm having. Totally dead motor and no faults on the screen. See if you can hear a very slight click from the motor when you activate the throttle or press the "-" bottom. That's what mine did. I took mind apart (the wrong way) and am now reassembling it so I can do further testing. I know the brake handles are working because I don't get the click if I have a brake on when I hit the throttle. So my guess right now is a bad signal from the throttle or a bad controller. My vote is a bad controller. BTW, I've got the 750w with a 20a controller.

Bob
 
UPDATE: OK, so I took the motor apart and fond nothing mechanically wrong with it. The only electrical problem I found are the damaged wires as showed in my posting above. However, I sincerely believe I caused that damage while disassembling the motor. Should anyone decide to disassemble their motor do not take off the "8FUN" side first. The wires are not long enough allow the motor to completely open because they are glued in place on the other side of the motor. This silicon adhesive must be removed first. By doing it the way I did I strained the wiring and caused the silicon insulation to tear.

Bottom line I repaired the wiring damage and put the motor back together. I just tested it on the bench and it's exactly the way it was. When activating the throttle the motor gives a slight click. It also does this with the "-" bottom. And if you hold the throttle on and press the brake on and off the motor clicks each time you release the brake.

A few times the motor did turn slightly. Maybe 10 degrees of rotation and then stopped. It does this once out of every 20 or so times you activate the throttle. BTW, the screen never gives any fault indication.

So my friends any good ideas where to go from here? I guess I should try checking the voltage going to and from the throttle. Checking it going in is easy but with those plugs how can you check it coming out of the throttle?

Bob

PS...Anyone know where I can buy a new 10a or 25a controller for this thing? And maybe a new throttle. At this point I'm guessing it's one or the other.
 
speedmd said:
Mine is giving a very faint click inside the motor also. Very faint. Nothing else. Has to be a open circuit somewhere. Did not like the stock controller programs so may not be a all bad thing. Not sure best ways to rule things down quickly at this point.
Click to expand...

I agree there's likely an open circuit but it's likely in the controller....and now where to get a controller? Most systems (I think including this one) will work without the brake switches working it you just unplug them. But I am confident my brake switches are working because there's no click if your holding a brake. So that leaves the throttle and controller. It could be the throttle but then why the click? That's why I am jumping straight to the controller. I'd be happy to buy a new controller if only I knew where to get one.

BTW, what model do you have?

PS..As I mention in last post......every now and then the motor will turn slightly and stop. Then nothing again for maybe 20 tries. Then it turns a few degrees again. If I knew more electronics (any) I'd try to go with a stand alone controller. That's the same thing that everyone did with the Cyclone motors with the built in controller.
 
I don't think is is a faulty throttle. The walking pace activation would still work if the throttle was faulty.

You are confident the hall wire plug inside the drive is well seated and that a contact hasn't just pushed out?

Measure the resistance of each phase wire to ground (power in ground and battery disconnected). If any show dead short, the controller is stuffed.

Controllers should be available. TomL got a 750W controller sent to him after he damaged his when working out how the program them. Sound like you need to start pushing your supplier.
 
A faint click on startup attempt sounds like a shorted phase. Most common reson is shorted mosfet, most likely low side. That is easy to check:
1. Take a multimeter and switch it to diode (-<|-) mode.
2. Connect red wire to B-.
3. Connect black wire to each phase. You should see redings around 300-700. If you see something like 002, then you have a blown mosfet. Replace it or bring the unit to electronics workshop to do the job.
4. Repeat steps 2 and 3, but with B+ and switch black with red.
 
I've experienced that when dis-/assembling the motor, there is a white 5 or 6-pin connector inside the housing and it is only hold in place with some elastic glue or sealant. This connection is prone to fail when assembling the motor, it is possible to secure correct connectivity with a wood stick from behind when assembling the house.

Sorry I have no pictures myself, this one is from this thread.
2014-04-09060350_zps1b777312.jpg


/Philip
 
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