Bafang 750w mid motor power issue

Maybe M@ can tell us how this one looks.
The actual link was easy to find:


Samsung/LG 21700 cells which means one or the other. What they are saying in the specs doesn't add up. They list "Peak current" as 80a, which is quite a lot. But then they also list "Max constant discharge current" as only 30a. Thats mighty unusual. An 80a peak BMS is a premium performer. Thats a high performance number. Continuous limit underneath an 80a peak should be around 60a. But they say its waaaaaay down at 30a. That ain't right. One number or the other is bogus. Probably the peak current but who knows when you catch them BS'ing like that?

Also they say the charge cycles are 1600 and we know that is flat out BS. You can fudge battery cycling test methodology to get a number of 1600 but its not an industry standard measure when you do that by any means. 1600 cycles would be achievable (roughly) with a 30% Depth of Discharge, so you charge only to 80% and drain it down only to 50%. That should get you about 1500-1600 cycles. Its total crap to be selling a battery and pretending that it has special "extended cycle life" cells when there is no such thing. So if they are lying about this what else did they put over on you thats not so obvious?


As far as I am concerned everything on AliExpress looks bad. It is a venue where the seller is effectively unaccountable for quality. Pretty much just as bad as Amazon. I buy lots of stuff on Ali, as well as Amazon, but never batteries. The seller can say anything they want. I have seen buyers who were told to ship a battery back to China at their expense for an evaluation, only to be told by the seller (who was UPP) that the pack is fine and then shipped it back to them.

I have also personally bought a pack where I specified Samsung 25R cells, but thats not what was actually provided inside. Counterfeits are commonplace.
  • UPP (Unit Pack Power) is loved by many for their low prices but their quality was so horrific they were banned from sale by the UK government, and the US CPSC recommended a stop-use and disposal for anyone who owned one. CPSC also noted UPP refused to do a recall.
  • EM3EV is a source in China with a well-deserved good reputation. I don't buy from them personally but they are the standout.
  • I do my battery buying these days from Bicycle Motorworks in Pennsylvania. USA built. A 52v 20ah battery costs $664, which is not expensive for a safe, well built battery pack. Puts the $220 battery prices in perspective.
 
  • I do my battery buying these days from Bicycle Motorworks in Pennsylvania. USA built. A 52v 20ah battery costs $664, which is not expensive for a safe, well built battery pack. Puts the $220 battery prices in perspective.
Back in my motoredbike days i used to buy alot of stuff from Matt.

I'll have to remember he makes batteries now :)
 
I did a full how-to here. The article includes links to the tools that let you get into the rich settings interface that is available for BBSxx motors.


This is actually an update to an article I first wrote in 2021. As such I let all the descriptions of what every setting is reside in the original article. So while the article I am linking shows very refined, kinder/gentler settings, and those are the ones I would use as examples of what to do, the full explainer is the original article.

And while I point to the BBSHD in the title, the 'HD is the same as the '02 insofar as these settings are concerned. So these settings and methods apply to you just as they do for a BBSHD.

To answer your specific question, you want to go to the Basic Screen and set the Current Limit down from its default (which is probably 25a) to 10a. I say 10a because that is a number so low it is likely to be underneath your battery BMS' Continuous current limit. Probably well underneath it. If your battery has a 30a peak, I would expect the continuous limit is 15a, or if you are lucky its 20. I would try 10 and if the bike is reliable, go to 11, then 12 and so on until the problem reoccurs and you know where the upper limit is.

Unfortunately, reducing the current limit reduces the usefulness of the motor. The amps translate to torque on the drivetrain. The more amps, the more oomph you have accelerating from a stop. Take that away and the motor is gutless. But what we're trying to do here is just figure out the problem. I think long term if you want proper performance you will need a proper battery with a 30a continuous current limit (you don't want to match at 25 because there can still be some overlap that pops the bms if you don't allow for a little fudge in your bms' rating).
What I have is definitely a battery issue because I can simulate the failure by starting out with a fully charged battery, and then attach a 200-Watt light bulb and the BMS shut down at the same voltage every time.

I would like to thank everyone for their input.
 
Back in my motoredbike days i used to buy alot of stuff from Matt.

I'll have to remember he makes batteries now :)
He's a good guy. I worked with him directly to make both of my custom Bullitt packs, and he built them to some pretty tight size specs. Unfortunately he no longer does custom packs. But with any luck I won't need a replacement for a lonnnnng time.

The packs he sells off the shelf, he doesn't build until he gets an order. So always fresh stuff.
 
What I have is definitely a battery issue because I can simulate the failure by starting out with a fully charged battery, and then attach a 200-Watt light bulb and the BMS shut down at the same voltage every time.

I would like to thank everyone for their input.
What I have is definitely a battery issue because I can simulate the failure by starting out with a fully charged battery, and then attach a 200-Watt light bulb and the BMS shut down at the same voltage every time.

I would like to thank everyone for their input.
I cannot find any setting in my DPC 18 display that allows me to change amperage.
 
I did a full how-to here. The article includes links to the tools that let you get into the rich settings interface that is available for BBSxx motors.


This is actually an update to an article I first wrote in 2021. As such I let all the descriptions of what every setting is reside in the original article. So while the article I am linking shows very refined, kinder/gentler settings, and those are the ones I would use as examples of what to do, the full explainer is the original article.

And while I point to the BBSHD in the title, the 'HD is the same as the '02 insofar as these settings are concerned. So these settings and methods apply to you just as they do for a BBSHD.

To answer your specific question, you want to go to the Basic Screen and set the Current Limit down from its default (which is probably 25a) to 10a. I say 10a because that is a number so low it is likely to be underneath your battery BMS' Continuous current limit. Probably well underneath it. If your battery has a 30a peak, I would expect the continuous limit is 15a, or if you are lucky its 20. I would try 10 and if the bike is reliable, go to 11, then 12 and so on until the problem reoccurs and you know where the upper limit is.

Unfortunately, reducing the current limit reduces the usefulness of the motor. The amps translate to torque on the drivetrain. The more amps, the more oomph you have accelerating from a stop. Take that away and the motor is gutless. But what we're trying to do here is just figure out the problem. I think long term if you want proper performance you will need a proper battery with a 30a continuous current limit (you don't want to match at 25 because there can still be some overlap that pops the bms if you don't allow for a little fudge in your bms' rating).
Your talesontwowheels comes up as a dangerous website, so I cannot read your article.

I looked through the settings on my DPC 18 display and cannot find any place to change the amps.
 
Your talesontwowheels comes up as a dangerous website, so I cannot read your article.

I looked through the settings on my DPC 18 display and cannot find any place to change the amps.
Thats the first time I have heard that from anyone. It gets hundreds of visits per day and is a generic Wordpress site. I give links to the various pages all the time and never hear that about it. What are you using for security software?


That setting is housed within the motor controller. At a lower level than you can get at with the display. You have to use software meant to give you access to the settings interface. You COULD buy an Eggrider v2 display and get to them that way, but I would very much recommend against that. ER's have never lost their occasional bugginess and they charge about US$100 to give you something that is free otherwise.
 
I did a full how-to here. The article includes links to the tools that let you get into the rich settings interface that is available for BBSxx motors.


This is actually an update to an article I first wrote in 2021. As such I let all the descriptions of what every setting is reside in the original article. So while the article I am linking shows very refined, kinder/gentler settings, and those are the ones I would use as examples of what to do, the full explainer is the original article.

And while I point to the BBSHD in the title, the 'HD is the same as the '02 insofar as these settings are concerned. So these settings and methods apply to you just as they do for a BBSHD.

To answer your specific question, you want to go to the Basic Screen and set the Current Limit down from its default (which is probably 25a) to 10a. I say 10a because that is a number so low it is likely to be underneath your battery BMS' Continuous current limit. Probably well underneath it. If your battery has a 30a peak, I would expect the continuous limit is 15a, or if you are lucky its 20. I would try 10 and if the bike is reliable, go to 11, then 12 and so on until the problem reoccurs and you know where the upper limit is.

Unfortunately, reducing the current limit reduces the usefulness of the motor. The amps translate to torque on the drivetrain. The more amps, the more oomph you have accelerating from a stop. Take that away and the motor is gutless. But what we're trying to do here is just figure out the problem. I think long term if you want proper performance you will need a proper battery with a 30a continuous current limit (you don't want to match at 25 because there can still be some overlap that pops the bms if you don't allow for a little fudge in your bms' rating).
Your talesontwowheels link comes up as a dangerous website and I cannot enter it.

When I look in the settings on my DPC 18 display there is no changing amps anywhere in there.
Thats the first time I have heard that from anyone. It gets hundreds of visits per day and is a generic Wordpress site. I give links to the various pages all the time and never hear that about it. What are you using for security software?


That setting is housed within the motor controller. At a lower level than you can get at with the display. You have to use software meant to give you access to the settings interface. You COULD buy an Eggrider v2 display and get to them that way, but I would very much recommend against that. ER's have never lost their occasional bugginess and they charge about US$100 to give you something that is free otherwise.
I tried opening that link in both Chrome and Microsoft Edge. Both browsers prevent me from entering the talesontwowheels site. I get this ERR_SSL_PROTOCOL_ERROR
 
I already mentioned why your DPC18 doesn't show anything in my previous post.

An ssl protocol error usually means an outdated browser that is still trying to use ssl. You used to see this a lot a couple of years ago when SSL was retired and replaced by TLS. If your browser is trying to use SSL as a secure protocol that could be the problem. I examined the secure certificate and it only lists TLS protocols so that would point to your browser wanting the old SSL and not supporting TLS.


I was able to test my site on SSLSoft and got 96 site reputation tests. 94 of which came up green, one undetermined and one (GridInSoft) said I was an adult content site distributing malware. I went to their site, got a reputation report on my site and that report had a link for me to file an appeal. I did, and amazingly I got this within the hour. Looks like it was written by a human:

Dear Matt,

I sincerely apologize for the inconvenience caused by the article regarding talesontwowheels.com

We manually reviewed your site and updated its classification accordingly.
If you have any questions, please do not hesitate to contact us.

--
Sincerely,
<contact info redacted>

And... they are in Ukraine so its the middle of the night over there.

This forked totally off-topic but if you hadn't had these problems I never would have known this one source had made this mistake. So thanks for that :-)
 
I already mentioned why your DPC18 doesn't show anything in my previous post.

An ssl protocol error usually means an outdated browser that is still trying to use ssl. You used to see this a lot a couple of years ago when SSL was retired and replaced by TLS. If your browser is trying to use SSL as a secure protocol that could be the problem. I examined the secure certificate and it only lists TLS protocols so that would point to your browser wanting the old SSL and not supporting TLS.


I was able to test my site on SSLSoft and got 96 site reputation tests. 94 of which came up green, one undetermined and one (GridInSoft) said I was an adult content site distributing malware. I went to their site, got a reputation report on my site and that report had a link for me to file an appeal. I did, and amazingly I got this within the hour. Looks like it was written by a human:

Dear Matt,

I sincerely apologize for the inconvenience caused by the article regarding talesontwowheels.com
We manually reviewed your site and updated its classification accordingly.
If you have any questions, please do not hesitate to contact us.
--
Sincerely,
<contact info redacted>

And... they are in Ukraine so its the middle of the night over there.

This forked totally off-topic but if you hadn't had these problems I never would have known this one source had made this mistake. So thanks for that :-)
I have tried Thunderbird, Microsoft Edge, Google Chrome and Sea Monkey. I get the same SSL error in all of them. They are all the most current versions of each browser.
 
I already mentioned why your DPC18 doesn't show anything in my previous post.

An ssl protocol error usually means an outdated browser that is still trying to use ssl. You used to see this a lot a couple of years ago when SSL was retired and replaced by TLS. If your browser is trying to use SSL as a secure protocol that could be the problem. I examined the secure certificate and it only lists TLS protocols so that would point to your browser wanting the old SSL and not supporting TLS.


I was able to test my site on SSLSoft and got 96 site reputation tests. 94 of which came up green, one undetermined and one (GridInSoft) said I was an adult content site distributing malware. I went to their site, got a reputation report on my site and that report had a link for me to file an appeal. I did, and amazingly I got this within the hour. Looks like it was written by a human:

Dear Matt,

I sincerely apologize for the inconvenience caused by the article regarding talesontwowheels.com
We manually reviewed your site and updated its classification accordingly.
If you have any questions, please do not hesitate to contact us.
--
Sincerely,
<contact info redacted>

And... they are in Ukraine so its the middle of the night over there.

This forked totally off-topic but if you hadn't had these problems I never would have known this one source had made this mistake. So thanks for that :-)
The resolution of the problem has allowed me to log into the site now.

So, it worked out for both of us and who knows possibly many other future people trying to click on that link.

Thank you for going through those extra steps to clear up the link.
 
Back
Top