New Bafang Crank-Drives

[samsavvas]

My first test ride PAS worked fine, after removing and putting the batteries back in PAS stopped working. I might of changed a config item when i Checked the wheel size. Any ideas ? PAS level selected with the +- keys but nothing when pedaling. Throttle works fine

Notice any 'error signal' at the display? Are you getting a speed readout on the display when riding with the throttle? Have you tried the old PC trick - turning off and then on again to maybe 'reboot'

Savvas.

 

[LyonNightroad]

I am starting to get a grinding noise at high loads and I suspect it is the nylon gear stripping out. Are replacement nylon gears available for the bbs-02?

 

[teslanv]

I am starting to get a grinding noise at high loads and I suspect it is the nylon gear stripping out. Are replacement nylon gears available for the bbs-02?

Me too. Sent a video to lcrewse. Still waiting to hear back with diagnosis.

 

[jateureka]

Is it only the BBS02 versions that are having this gear stripping issue?

Is it because you are doing a lot of throttle only riding or carrying heavy loads?

 

[LyonNightroad]

I do run it hard but its only been 150 miles. That just tells me that it will start to wear out after 500 miles of lighter riding. I dont mind replacing parts but those parts need to be available. I'm going to tear it apart tonight and diagnose it.

 

[Rollodo]

I do run it hard but its only been 150 miles. That just tells me that it will start to wear out after 500 miles of lighter riding. I dont mind replacing parts but those parts need to be available. I'm going to tear it apart tonight and diagnose it.

By 'hard', do you mean pushing high amps in higher gears? If yes, you shouldn't be doing that, unless you're treating it as a test unit and you can afford to push it beyond its limit. What watts is it consuming?

 

[covert]

Notice any 'error signal' at the display? Are you getting a speed readout on the display when riding with the throttle? Have you tried the old PC trick - turning off and then on again to maybe 'reboot'

Savvas.

No error messages at all.
Speed reading works.
Power pack out of it last night to charge. Back in it today and still no PAS

 

[Kepler]

Try unplugging your throttle and see if the PAS works then. Might be that your throttle is slightly activated which in turn shuts down your PAS.

 

[neptronix]

I am starting to get a grinding noise at high loads and I suspect it is the nylon gear stripping out. Are replacement nylon gears available for the bbs-02?

I bet they did something stupid like use the same gears for the BBS01 and BBS02.
Do you get the motor unit warm at all when you were 'working it hard'?

When i get my 750w unit with the stock controller, i will run it a little below it's max rating and plan to rip the internal controller out in the future, replace it with an EB3, and run that at maximum amps it's designed for, but lower phase amps, to give the drive lower initial torque, which will extend the gear life dramatically if the stock controller is designed in such a way that it produces a shock of power as soon as you hit the throttle ( it's those shocks of high torque at low rpm that really munch on plastic gears - the early MAC and BMC motors suffered of this too due to poor controllers at the time... )

So i have a questions for you guys while i'm waiting on cell_man/em3ev to get back to me on my order... when you hit the throttle from a total stop, is the power band of the motor from 0rpm up to the maximum speed it will cruise at linear(flat), or does it accelerate strongly from a stall, but sort of tail off the higher the RPM as a hub motor does?

You can test this and perceive whether the power band is linear or stronger at 0rpm by engaging it at one of your higher speed gears to find out.

If bafang didn't add much in the way of phase:battery amplication, it should be a pretty linear powerband.

 

[covert]

Try unplugging your throttle and see if the PAS works then. Might be that your throttle is slightly activated which in turn shuts down your PAS.

Good idea, but didn't help. Throttle load hangout out and still no PAS.

 

[Kepler]

I think the next move is to open up the drive. There is a plug in the controller section of the drive that connects the PAS sensor to the controller. You need to have a look and check if hasn't come loose.

 

[LyonNightroad]

Great News, after tearing it apart the gears are in excellent condition. It ended up being the same issue someone else had in this thread a few dozen pages ago. The 5 screws connecting the freewheel to the final reduction gear were loose. Tightened them up and regreased the whole thing. Looks like at least one batch came with loose screws. Bad news is that it is a serious pain in the ass to get to the screws. You have to tear the whole thing apart and deal with a C clip from hell. Not to mention loose ball bearings. But after 2 hours work all is well. I expect many many more miles out of the gears, they look new. I ride 30mph for 10+ miles. Max 25amps the whole time.

 

[amigafan2003]

I confirm. I can read the parameters, change them and write them back and my unit is still working ...

Excellent.

One USB > TTL adapter on the way. Now to figure out what all the settings are.

 

[radoCol]

Great News, after tearing it apart the gears are in excellent condition. It ended up being the same issue someone else had in this thread a few dozen pages ago. The 5 screws connecting the freewheel to the final reduction gear were lose. Tightened them up and regreased the whole thing. Looks like at least one batch came with lose screws. Bad news is that it is a serious pain in the ass to get to the screws. You have to tear the whole thing apart and deal with a C clip from hell. Not to mention loose ball bearings. But after 2 hours work all is well. I expect many many more miles out of the gears, they look new. I ride 30mph for 10+ miles. Max 25amps the whole time.

Great! How to check this before riding? I mean kind of a quick check - pull/push from crank to the sideways or just rotating and try to hear/see loose part? It is a good practice to do some kind of test to see loosen parts before driving, right?

-rado

 

[LyonNightroad]

Great News, after tearing it apart the gears are in excellent condition. It ended up being the same issue someone else had in this thread a few dozen pages ago. The 5 screws connecting the freewheel to the final reduction gear were lose. Tightened them up and regreased the whole thing. Looks like at least one batch came with lose screws. Bad news is that it is a serious pain in the ass to get to the screws. You have to tear the whole thing apart and deal with a C clip from hell. Not to mention loose ball bearings. But after 2 hours work all is well. I expect many many more miles out of the gears, they look new. I ride 30mph for 10+ miles. Max 25amps the whole time.

Great! How to check this before riding? I mean kind of a quick check - pull/push from crank to the sideways or just rotating and try to hear/see loose part? It is a good practice to do some kind of test to see loosen parts before driving, right?

-rado

This is not an easy thing to check. You must entirely disassemble the motor to get to these screws. I would only check for these loose screws if your motor is vibrating/grinding under load

 

[borsuk]

In other words I should be able to drive over 50km with my 10Ah battery!

I think that even more. Look at the table with my results for BBS01 350W :

And here's my route profiles :
http://www.borsukk.evbox.pl/bbs01eng/track1.jpg
http://www.borsukk.evbox.pl/bbs01eng/track2.jpg
http://www.borsukk.evbox.pl/bbs01eng/track3.jpg
My bike:
http://www.borsukk.evbox.pl/bbs01eng/ebike1.jpg
http://www.borsukk.evbox.pl/bbs01eng/ebike2.jpg
borsuk

 

[Kepler]

Great News, after tearing it apart the gears are in excellent condition. It ended up being the same issue someone else had in this thread a few dozen pages ago. The 5 screws connecting the freewheel to the final reduction gear were lose. Tightened them up and regreased the whole thing. Looks like at least one batch came with lose screws. Bad news is that it is a serious pain in the ass to get to the screws. You have to tear the whole thing apart and deal with a C clip from hell. Not to mention loose ball bearings. But after 2 hours work all is well. I expect many many more miles out of the gears, they look new. I ride 30mph for 10+ miles. Max 25amps the whole time.

Great! How to check this before riding? I mean kind of a quick check - pull/push from crank to the sideways or just rotating and try to hear/see loose part? It is a good practice to do some kind of test to see loosen parts before driving, right?

-rado

This is not an easy thing to check. You must entirely disassemble the motor to get to these screws. I would only check for these loose screws if your motor is vibrating/grinding under load

Not quite necessary to pull the whole drive apart. Just need to disassemble the crank section of the drive. Need to be a bit careful of the thust bearings when pulling out the bottom bracket shaft though that's is for sure.
The C clip can be a bit tricky but with the correct tools, not too bad to remove.

When mine came loose, I could feel quite a bit of side to side play in the chainring.

 

[teslanv]

Great News, after tearing it apart the gears are in excellent condition. It ended up being the same issue someone else had in this thread a few dozen pages ago. The 5 screws connecting the freewheel to the final reduction gear were loose.

Any pics you can share?

 

[teslanv]

Riding home tonight, noticed a bit of unusual noise coming from the drive. When I got home, I took the chain off and ran the drive up. Sure enough, the unusual noise continued and sounded worse with the chain off, almost like a grinding noise. Next I checked for play both in the cranks and in the chain ring. there was a little bit of play in the cranks but quite a bit in the chain ring. Not good.

First thing first, removed the cranks and chain guard and checked the bolts holding the chain ring on. All tight. So further investigation required. Removed the drive from the bike and and checked the locking nuts that set the tension on the thrust bearings. These were on the loose side so I tightened these up and re checked. All the play was gone from the cranks but the chain ring still continued to have significant play.

Was getting a bit worried now thinking the worst like perhaps a worn shaft or failed bearing. Removed the main gear cover and thrust locking nuts then extracted the BB shaft. This comes out with the final gear and free wheel assembly. Next I removed the PAS sensor ring which is held in place with a C clip. Finally the culprit was found. The 5 countersunk screws that hold the final gear on to the free wheel assembly were all loose. Excellent, a simple fix after all. Removed the screws and added new loctite then re assembled making sure the screws were torqued down firmly. All play was now gone.



Took the opportunity to clean the final gear and re grease. Re assembled the drive and reinstalled on to the bike followed by a quick test run. All fixed and as quiet as the first day I installed the drive. Back to being a happy camper

I'd guess I have the same problem Kepler. Similar symptoms. What is the manufacture date of your drive? First size digits of the serial are 131127 (Nov. 27, 2013).

 

[Ken Taylor]

In other words I should be able to drive over 50km with my 10Ah battery!

I think that even more. Look at the table with my results for BBS01 350W :

Borsuk's numbers of 4.2-2.5 wh/km look lower than lots I see but they need to be expressed differently to be meaningful. The 2.8 wh/km I managed on this 90 km ride http://app.strava.com/activities/127316925/embed/933d1565bec0137dbe5beca7eb01fb6c5021bd8b last Sunday on a different motor is towards the lower end of the range. Does that make it good compared to the BBS02? Borsuk doesn't mention speed but

... and it so easy to maintain 25-28km/h speed!

This is a reasonable cycling speed and my 27.3 km/hr average was towards the upper end. However, the 12 people I was with did it on 0 wh/km.

I could have matched the 0 wh/km but without that 2.6 wh/km, I'd have been dropped on the hills. Based on heart rate measurements, in Strava's opinion I endured an Extreme Suffer Score. Reducing the suffering would require increasing the 2.6 wh/km figure.

 

[Tom L]

So does this mean we finally have programming cracked? If so this is milestone day for the Bafang mid drive thread. Well done to all that have contributed..

Seems so . In fact I just shared what I learned from other people on french cyclurba.fr forum.

Ben-B - can you please confirm that you are able to communicate with the controller and alter the program without forking the unit.

I confirm. I can read the parameters, change them and write them back and my unit is still working ...

What model of bafang do you have.

I have a 36V18A BBS01 bought in august 2013 from CNEbikes with a C950 display. Seems that Electorbikes with a more recent unit (colored connectors) is able to communicate with only the 3 communication wires (gnd,rx,tx) connected which I can't.

A link to purchase the convertor and or type used

http://cgi.ebay.fr/ws/eBayISAPI.dll...eName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649
I bought this one but I think any you can find by typing "USB to serial" or "USB to TTL" or "USB to FTDI" will do the job.

I've been away and missed all the fun! Good job guys.

Who would have thought the parameters were stored in the display not the controller?

My TTL interface arrived while I was away (no new controller yet though) so I'll have a go at putting together a how-to if I can get mine hooked up tomorrow night. I'm interested to see if a 3V logic interface board will work. If so they are only a couple of bucks on ebay.

 

[ErikDK]

Could someone please try to configure a lower voltage than 36V for a BBS-01 ?

My battery infrastructure is mostly 7s packs, so being able to use one for my son's bike would be convenient.

The other way around, I also have 2X 6S 8000mAh packs, which I would like to use as well, for longer trips.

 

[tomjasz]

Are replacement nylon gears available for the bbs-02?

Who has parts and support for these drives? Lectriccycles is the only USA option?
I'm just about ready to flip the coin and pick a setup. On top is the BBS01 350W. The idea that parts might be a problem and the small, but perhaps signifiant, number of problems with factory build has me concerned. Who has parts available? I REALLY want to make my purchase with cell_man, but do I have to learn to wait days for an answer to questions? Is this just the nature of the beast? Buy and cross fingers?

Do I need to just STFU and quit whining?

As an aside, I continue to be stunned by the lack of access to electric bicycles in the US.

One week and maybe I'm even more confused.


Tom

 

[Rollodo]

Are replacement nylon gears available for the bbs-02?

Who has parts and support for these drives? Lectriccycles is the only USA option?

Maybe Mwkeefer might help.
http://endless-sphere.com/forums/memberlist.php?mode=viewprofile&u=12847

 

[ben--b]

Who would have thought the parameters were stored in the display not the controller?

No, no, the parameters are stored in the controller. The display is disconnected when programming ... At least on my setup.