ETM upgrade for BBS01B 250W

[SkyMonkey]

I have the BBS01B 48v 250W mid drive installed on my road tourer and now am experiencing the same 'cadence wall' noticed by @Deere John in the thread linked below.
Assist tapers and cuts out at a cadence of 83 rpm according to the Bafang specs for the 48v model.
At my natural cadence I bounce in and out of the top of the 'assist' zone.

He installed a 500W BBS02B stator/rotor kit and seemed to solve the problem on his 36v build.
This made it effectively an Extra Torque Model, but without the 500W controller, keeping the fixed 15A (I think) controller.
That would hopefully raise the 48v 'cadence wall' to 118 rpm, way above my natural 90-ish cadence.
His thread is now over 5 years old.
Have any other Pedelecs members attempted a similar upgrade since?
How did it go? Should I get the controller too?

I can find the 48v stator/rotor kits around the UK internet, but the cheapest seems to be this one from Amazon UK.
Anyone used them? Are there many fake parts out there to avoid?

Cheers.

https://www.amazon.co.uk/gp/product/B0CF5FFS3Q/ref=ox_sc_saved_title_4?smid=A6XQPVRXUZ1KA&th=1

Bafang BBS01 changing RPM

Hi all, I have long been disturbed about the BBS01 low speed. Only rated 78 rpm at 36V/250W version. Personally I like riding at about 80-100 rpm or something like that. So the BBS01 cuts out just when beginning to reach the sweet spot. How to fix this? I guess you can't change this through...

www.pedelecs.co.uk

 

[Raboa]

I don't if this helps, ship to UK

Bafang 48V 750W 500W 36V 350W 250W BBS motor core for replacement -GreenBikeKit BBS, ebike batteries, Bafang M620, Bafang M600, Bafang M500, Bafang M510, KT controller with display-GreenBikeKit.com

Bafang 48V 750W 500W 36V 350W 250W BBS motor core for replacement ;

www.greenbikekit.com

I have the same problem, it's more money to spend though, Bafang should sort it out

 

[saneagle]

I have the BBS01B 48v 250W mid drive installed on my road tourer and now am experiencing the same 'cadence wall' noticed by @Deere John in the thread linked below.
Assist tapers and cuts out at a cadence of 83 rpm according to the Bafang specs for the 48v model.
At my natural cadence I bounce in and out of the top of the 'assist' zone.

He installed a 500W BBS02B stator/rotor kit and seemed to solve the problem on his 36v build.
This made it effectively an Extra Torque Model, but without the 500W controller, keeping the fixed 15A (I think) controller.
That would hopefully raise the 48v 'cadence wall' to 118 rpm, way above my natural 90-ish cadence.
His thread is now over 5 years old.
Have any other Pedelecs members attempted a similar upgrade since?
How did it go? Should I get the controller too?

I can find the 48v stator/rotor kits around the UK internet, but the cheapest seems to be this one from Amazon UK.
Anyone used them? Are there many fake parts out there to avoid?

Cheers.

https://www.amazon.co.uk/gp/product/B0CF5FFS3Q/ref=ox_sc_saved_title_4?smid=A6XQPVRXUZ1KA&th=1

Bafang BBS01 changing RPM

Hi all, I have long been disturbed about the BBS01 low speed. Only rated 78 rpm at 36V/250W version. Personally I like riding at about 80-100 rpm or something like that. So the BBS01 cuts out just when beginning to reach the sweet spot. How to fix this? I guess you can't change this through...

www.pedelecs.co.uk

That sounds back to front to me. It would make the motor run 30% slower, not faster. To make one go 30% faster, you need a 36v motor run at 48v. If you have a 48v one, you could get a small improvement (about 8% increase in speed) by running at 52v (14S). A36v one run at 12S would increase the 83 rpm to around 100 rpm. It would probably work with the 36v controller if you turned down the current a bit to say 12A.

 

[SkyMonkey]

I don't if this helps, ship to UK

Thanks @Raboa.
That does seem like a better deal, especially with the seals and gasket included.
I'm in no real hurry, so shipping from the US is no problem.

 

[SkyMonkey]

That sounds back to front to me. It would make the motor run 30% slower, not faster. To make one go 30% faster, you need a 36v motor run at 48v. If you have a 48v one, you could get a small improvement (about 8% increase in speed) by running at 52v (14S). A36v one run at 12S would increase the 83 rpm to around 100 rpm. It would probably work with the 36v controller if you turned down the current a bit to say 12A.

Well that's why I'm asking.
I only have the one instance of @Deere John doing the stator/rotor only upgrade, and he's not been seen since April.
He did the upgrade on a BBS01B 250W 36v system with a BBS02B 500W 36v stator/rotor kit.
He didn't change the controller (so amps still fixed at 15A).
He didn't change the battery (so still 36v).

His thread is worth a read.
Here is a quote from his assessment after installing (post #27):

"Ok, now I have two rides with the new BBS01.5.

Short summary: Hard to tell what I felt.

I think I start in the other end. I certainly know what I NOT felt.

No more motor cutting off on me when pedalling normal. No matter what cadence it assisted anyway. I had to pedal like a maniac to get it to cut off because then finally outrun motor rpm. So this huge issue is no more.

I just swapped rotor/stator. Same (250W) controller, same programming.

So, what did I feel? It felt great! It feels like the 36V BBS01 should have felt from beginning I think. This cadence issue was really frustrating. It was worth every penny to get it fixed. Biking experience is so much better now when I just can pedal at whatever cadence I want and still get the assist I want."

 

[Raboa]

You change the money to pounds at the bottom of the screen.

 

[saneagle]

Well that's why I'm asking.
I only have the one instance of @Deere John doing the stator/rotor only upgrade, and he's not been seen since April.
He did the upgrade on a BBS01B 250W 36v system with a BBS02B 500W 36v stator/rotor kit.
He didn't change the controller (so amps still fixed at 15A).
He didn't change the battery (so still 36v).

His thread is worth a read.
Here is a quote from his assessment after installing (post #27):

"Ok, now I have two rides with the new BBS01.5.

Short summary: Hard to tell what I felt.

I think I start in the other end. I certainly know what I NOT felt.

No more motor cutting off on me when pedalling normal. No matter what cadence it assisted anyway. I had to pedal like a maniac to get it to cut off because then finally outrun motor rpm. So this huge issue is no more.

I just swapped rotor/stator. Same (250W) controller, same programming.

So, what did I feel? It felt great! It feels like the 36V BBS01 should have felt from beginning I think. This cadence issue was really frustrating. It was worth every penny to get it fixed. Biking experience is so much better now when I just can pedal at whatever cadence I want and still get the assist I want."

I think you're either not explaining it well or you misunderstand what he did. The basic concept is that the more volts you give to a motor, the faster it will spin. If you want 30% more speed, you run a 36v motor at 48v. The sensible way to do it is simply to change the controller because it bolts on the side of the motor and is easy to replace. The alternative is to take a 48v motor that already has the 48v controller, and swap the rotor for a 36v one. That's much harder because you have to completely dismantle the motor. It only would make sense if you already have the 48v motor and are unhappy with it, which is your situation, so, yes you can swap the rotor, but it must be for a 36v one the same size as what you have.

 

[SkyMonkey]

I think you're either not explaining it well or you misunderstand what he did. The basic concept is that the more volts you give to a motor, the faster it will spin. If you want 30% more speed, you run a 36v motor at 48v. The sensible way to do it is simply to change the controller because it bolts on the side of the motor and is easy to replace. The alternative is to take a 48v motor that already has the 48v controller, and swap the rotor for a 36v one. That's much harder because you have to completely dismantle the motor. It only would make sense if you already have the 48v motor and are unhappy with it, which is your situation, so, yes you can swap the rotor, but it must be for a 36v one the same size as what you have.

Hi @saneagle.

I am not trying to explain anything.
I am referencing & quoting @Deere John, and asking questions to help my understanding.
Have you read the whole thread I linked in my first post?

I have just re-read the thread again, and he says he has done exactly as I quoted above.
I will re-state what he says he had done. for clarity of 'explanation'.

New 36v BBS02B 500W stator/rotor.
Same 36v BBS01B 250W Controller @15A.
Same 36v battery.
Result: higher Max rpm available before assist cuts out (i.e. from 78rpm, changed to 113rpm).

So, either it works, or @Deere John is a liar.

Can anyone else confirm or debunk (with actual experience, not just conjecture or a different procedure).

 

[SkyMonkey]

Well, I have searched the net for any advice and everything I find is slanted towards either:
Getting a BBS02B instead.
Adding more volts (as @saneagle recommended).
Using a 36v stator/rotor kit (also as @saneagle recommended).
Or turning the BBS01B effectively into a BBS02B with both a controller and stator/rotor change.

I really do wish @Deere John was still active (lord knows I've dropped his name enough times!).

I think I will go ahead and try just a new stator/rotor kit to begin with and report back.
If no joy, then try the BBS02B controller too.
As he pointed out, the casing is where the voltage and wattage are stamped (for apparent legality).
I'm not willing to mess around with voltage changes, so all will be at 48v.

 

[guerney]

@SkyMonkey - Is it possible you could recondition yourself to feel comfortable at a lower cadence? When I first started cycling decades ago on racing bikes (there was a decades long break until the pandemic), I was taught to "Twiddle", ie pedal at high cadence for efficiency. This became ingrained and felt natural. As time passed, very gradually I felt more comfortable pedalling at a lower RPM, and that became my comfortable naural cadence. When I resumed cycling, with my BBS01B conversion, it took a little while to adjust to a higher cadence again. Now I'm completely fine with it. Although I'm intrigued and look forward to seeing the results of your project, I'm wondering if you could save money and trouble by fiddling about with your gearing etc. and simply retraining yourself somehow?

 

[soundwave]

just fit a throttle

 

[SkyMonkey]

@SkyMonkey - Is it possible you could recondition yourself to feel comfortable at a lower cadence? When I first started cycling decades ago on racing bikes (there was a decades long break until the pandemic), I was taught to "Twiddle", ie pedal at high cadence for efiiciency. This became ingrained and felt natural. As time passed, very gradually I felt more comfortable pedalling at a lower RPM, and that became my comfortable naural cadence. When I resumed cycling, with my BBS01B conversion, it took a little while to adjust to a higher cadence again. Now I'm completely fine with it. Although I'm intrigued and look forward to seeing the results of your project, I'm wondering if you could save money and trouble by fiddling about with your gearing etc. and simply retraining yourself somehow?

Hi @guerney

That would be a cheap solution.
But I also ride an 'acoustic' carbon road bike, so the 'twiddle' is somewhat ingrained in me too.

The gearing is slanted to high torque/low(ish) speed, with a 42 chainring and 11-34 9-speed cassette.
I used to ride this bike a few years ago for fully loaded pannier touring with a triple chainring.

Anyway, economy and common sense go out of the window when 'perfection' may be attainable.
Plus, I am really enjoying this DIY E-Bike thing.
It has re-invigorated my lifelong love of bikes, and got me back on the other 'normal' bikes stowed away for so long in the cellar.
I'm a born tinkerer.

Not sure how a throttle would help in this situation @soundwave.
I have one installed but it is set as close to a 'walking' throttle as possible (and may go completely).
What I want is to 'cycle' naturally, not just push a button.

The problem is the BBS01B 'power band' is too low in the rpm range for me.
A BBS02B would really have been the best option, but I have to stay legal for my job.

My other hope for someone who had tried this was @Raboa, but judging by his earlier post he never took the plunge.

 

[saneagle]

Hi @guerney

That would be a cheap solution.
But I also ride an 'acoustic' carbon road bike, so the 'twiddle' is somewhat ingrained in me too.

The gearing is slanted to high torque/low(ish) speed, with a 42 chainring and 11-34 9-speed cassette.
I used to ride this bike a few years ago for fully loaded pannier touring with a triple chainring.

Anyway, economy and common sense go out of the window when 'perfection' may be attainable.
Plus, I am really enjoying this DIY E-Bike thing.
It has re-invigorated my lifelong love of bikes, and got me back on the other 'normal' bikes stowed away for so long in the cellar.
I'm a born tinkerer.

Not sure how a throttle would help in this situation @soundwave.
I have one installed but it is set as close to a 'walking' throttle as possible (and may go completely).
What I want is to 'cycle' naturally, not just push a button.

The problem is the BBS01B 'power band' is too low in the rpm range for me.
A BBS02B would really have been the best option, but I have to stay legal for my job.

My other hope for someone who had tried this was @Raboa, but judging by his earlier post he never took the plunge.

You're still misunderstanding something. All the BBS** motors have approximately the same maximum rpm when running them at their designated voltages. The BBS01B is the same as the BBS02B. If you want any of them to spin faster, you have to increase the voltage above the designated voltage, and the max rpm will increase in proportion.

Just a thought: Have you got your keep current programmed to something ridiculously low, which would give the symptoms you've described, or is it set to 100%?

 

[soundwave]

what rpm can u paddle at? my bosch motor gives max power at 120rpm.

tho i have a 20amp controller and no speed limit and at that rpm not 1 road bike has got past me in 10 years.

m8s bbshd has a 30amp controller tho you could use a 3rd party one and up the voltage and amps but the batt must be able to sustain the voltage and amps and if the stator gets to hot you can blow the windings or magnets.

Sabvoton 150A Controller UK

Sabvoton SVMC programmable sinewave motor controller works with high efficiency, less noise & lower energy consumption,which makes your electric vehicles or electric motorcycles more comfortable and easier to control. Our designed friendly interface for the programmable motor controller allows...

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put that on the washing machine

 

[guerney]

I twiddled for ages, then my legs became stronger, the bikes and inclines remained the same... so after some years I adopted a relaxed languid lower RPM cycling cadence with massive thick legs.

I tried the 42T and 48T before settling on the 52T, which is perfect for everything - hauls heavy trailers up steep hills, even with 15A, and is fast on the flats. Now that the controller is at 20A, I would probably try a 58T if I was certain the chainline would let me get away with a BCD spider adapter - I think there's enough power on 20" wheels.

then try the BBS02B controller too.

Does the BBS02B controller physically fit onto the BBS01B? I read somewhere the BBS02's doesn't. If it all fits, as you said opens up the prospect of an apparently legal 48V "500W" stealth 1200W BBS02B... (which I don't need, because of the magic mightiness of small wheels).

At my natural cadence I bounce in and out of the top of the 'assist' zone.

That would hopefully raise the 48v 'cadence wall' to 118 rpm, way above my natural 90-ish cadence.

I'd be curious to see your firmware settings, because judging by action camera video (the old one, which didn't have image stabilisation) my cadence is often about 90rpm, but I don't experience a reduction of assistance. Motor cuts out abruptly at 25kph because that's the way it's set up in firmware.

You've probably already seen all this:

Bafang central motor programming guide - Bafangers

Learn how to configure your Bafang motor to your liking and protect it from possible breakdowns with the appropriate USB cable and software.

www.bafangers.com

Bafang Programming - Learn how to improve your Bafang mid-drive ebike - Edrivenet

Learn how to improve your Bafang mid-drive ebike. Reprogramming your Bafang mid-drive system can improve the usability and performance of your ebike a lot.

edrivenet.com

My "Stop decay" is 0. "Current decay" is 8.

Current Decay (1-8): 8

The lower this setting, the faster the drive unit will decrease power as you pedal faster. You don’t want the power to cut down a lot if you pedal faster, so leave this to 8. This also is the default setting.

 

[SkyMonkey]

I am going off the published specs for the Bafang BBS series, as posted by Deere John:

 

[SkyMonkey]

I think I am going to go down the re-programming route this weekend.
Hopefully that will help with the problems I'm experiencing.
I did some tweaks when I first installed the motor, but having ridden for a month, there is definitely room for improvement.
And I'll screenshot this time so I know what I did.
I'll look at Keep Current for power at the top cadences (cheers @saneagle ).
Also, manoeuvring in slow traffic is quite jerky, so I'll be looking at the Pedal Assist tab 'Start' and 'Stop' settings (cheers @guerney).
100% speed all though the PAS levels now seems more logical to me now too.

But I've all but given up on setting the throttle to a legal 6 kph.
I would like it as an option for walking a fully loaded bike around easily.
Again, I can't remember how I tried to set it, but it's too fast and going up the gears ups the speed proportionately too.
Any advice on that would be welcome.

Cheers guys (and guy-esses?).

A full review and pics of the E-Sutra is coming soon BTW, I promise.

 

[sjpt]

But I've all but given up on setting the throttle to a legal 6 kph.
I would like it as an option for walking a fully loaded bike around easily.

Many controllers have a way of setting walk mode independently from any throttle.

The walk mode on my Lishui/XF07 is too fast though. It'd be fine on the flat (where I don't need it), but not going up steepish slippery chalk paths (where I do need it).

 

[SkyMonkey]

Many controllers have a way of setting walk mode independently from any throttle.

The walk mode on my Lishui/XF07 is too fast though. It'd be fine on the flat (where I don't need it), but not going up steepish slippery chalk paths (where I do need it).

The 500C controller does have the option to 'Walk' the bike at 6 kph by holding in the "-" button on the display.
But it requires quite a hard and continuous press on the button to keep it working.
My old and arthritic thumb can't maintain the pressure needed!
So it's pretty annoying that I know it can do it, but only by that method (so far).

 

[guerney]

But I've all but given up on setting the throttle to a legal 6 kph.
I would like it as an option for walking a fully loaded bike around easily.
Again, I can't remember how I tried to set it, but it's too fast and going up the gears ups the speed proportionately too.
Any advice on that would be welcome.

I wanted to see if a legal throttle was possible on the BBS01B - I managed that by setting my Level 0 for the throttle, and designating that level to the throttle. "Keep Current" 100%. Level 0 was set to some percentage of the 25kph speed limit, to limit the throttle's speed. Throttle Mode should be "Current" not speed. Despite my setting Level 0 to 40% of the speed limit (should really been 24% of 25kph = 6kph, can't recall if I tried that, haven't kept all of the screenshots) of the speed limit, in use it was about 4.2kph uphill. Much the same on level road. 6kph is the legal limit for independently operating throttles. No load speed with the wheel off the ground was higher. Can't recall the exact speed on level road, I really should have tilted the action camera on the helmet jawguard down to record speed on the display. I removed the throttle, but you might find some use for it set this way? After I broke the programming cable, I bought another and might do this again sometime.









In use uphill.