Bafang m820
- Thread starter Vsoria
- Start date
There is no logic in that! But I might as well give it a try..I discharged the battery to 5% - according to the Bafang display. I charged the battery and it fixed itself - the engine starts again without any problem, every time. Check it out for yourself if it helps you too
That is weird, since the newer softwares seems to have less output current.
I don't think, there will be any higher current firmwares. IMO it was just marketing fluf, now that Bosch is increasing their values with the FW. And if you would ask them, they could just claim "different way of measurement" or some other bullshit.
That is just my personal take.
That is just my personal take.
raggertje
Member
Hi,
After I had my engine out and installed I suddenly get error 30. I have tried a new display and main cable but still get the error. With the BESST tool I can not read the engine. Is my controller broken?
After I had my engine out and installed I suddenly get error 30. I have tried a new display and main cable but still get the error. With the BESST tool I can not read the engine. Is my controller broken?
mike_kelly
E*POWAH Elite
from the bafang manual:
"30" - Communication failed
Error code Cause Result
30 Communicate failed. The display shows the error code 30
and the motor cannot work.
Component Description
The display provides battery voltage, speed display, riding status, lamp status, etc., and can
also display the fault conditions of various electrical components of the pedelec.
Component Location
The display is installed on the handlebar.
Conditions for Running the Diagnostics
After the system is turned on, the diagnosis runs continuously.
Error Phenomenon
The display shows the error code 30 and the motor cannot work.
Conditions for Clearing the Error Code
After the diagnosis runs and passes, the system works normally.
Troubleshooting
Step 1 Check all connectors on the pedelec.
Check the cables and the connectors for the following conditions:
Inspect the control harness and accelerator pedal connector pins for the following:
• Loose connector • Corroded pins • Bent or broken pins • Dirt or debris in or on the connector
pins • Wire insulation damage • Connector shell broke
"30" - Communication failed
Error code Cause Result
30 Communicate failed. The display shows the error code 30
and the motor cannot work.
Component Description
The display provides battery voltage, speed display, riding status, lamp status, etc., and can
also display the fault conditions of various electrical components of the pedelec.
Component Location
The display is installed on the handlebar.
Conditions for Running the Diagnostics
After the system is turned on, the diagnosis runs continuously.
Error Phenomenon
The display shows the error code 30 and the motor cannot work.
Conditions for Clearing the Error Code
After the diagnosis runs and passes, the system works normally.
Troubleshooting
Step 1 Check all connectors on the pedelec.
Check the cables and the connectors for the following conditions:
Inspect the control harness and accelerator pedal connector pins for the following:
• Loose connector • Corroded pins • Bent or broken pins • Dirt or debris in or on the connector
pins • Wire insulation damage • Connector shell broke
I've owned my m820 for a year and a half now, theres no way its 80nm.
Mine claims 580 watts top in B mode, and unless its cold out it will overheat and throttle down to 300 watts after 30 min. I can't keep up with full powered ebikes, even my friend on an EP 7 Marin in his 2nd highest mode.
The chinese manufacturer of my carbon frame sold me a claimed 700 wh battery, and the useable range is stil less than my friends with 600 wh batteries on full powered ebikes. They run in their middle settings and while I'm dying they are chatting my ear off because they are putting next to no effort into pedaling, with me in S+ mode averaging a reported 400 watts of assistance.
At an average of 400 watts (reported) I get around 90 min of climbing before hitting 17% and a forced eco mode, so the number seem to be correct on that 700wh battery. Others on a full powered, 600wh Shimano or Bosch putting out much less effort than me have 40-50% battery remaining for a comparable climb. Either Bafang & the independent Chinese frame/battery manufacturer are lying proportionally, or (as I suspect) when pushing above 300 watts the m820 becomes very inefficient and loses tons of watts to heat. This hypothesis requires that the reported wattage output of the Bafang m820 is the input, not the output at the crank.
Anyways, thats my review of the m820. Other than being under powered and inefficient, its been rock solid reliable for two seasons with 0 maintenance.
Mine claims 580 watts top in B mode, and unless its cold out it will overheat and throttle down to 300 watts after 30 min. I can't keep up with full powered ebikes, even my friend on an EP 7 Marin in his 2nd highest mode.
The chinese manufacturer of my carbon frame sold me a claimed 700 wh battery, and the useable range is stil less than my friends with 600 wh batteries on full powered ebikes. They run in their middle settings and while I'm dying they are chatting my ear off because they are putting next to no effort into pedaling, with me in S+ mode averaging a reported 400 watts of assistance.
At an average of 400 watts (reported) I get around 90 min of climbing before hitting 17% and a forced eco mode, so the number seem to be correct on that 700wh battery. Others on a full powered, 600wh Shimano or Bosch putting out much less effort than me have 40-50% battery remaining for a comparable climb. Either Bafang & the independent Chinese frame/battery manufacturer are lying proportionally, or (as I suspect) when pushing above 300 watts the m820 becomes very inefficient and loses tons of watts to heat. This hypothesis requires that the reported wattage output of the Bafang m820 is the input, not the output at the crank.
Anyways, thats my review of the m820. Other than being under powered and inefficient, its been rock solid reliable for two seasons with 0 maintenance.
How wheigt you are ? i'm 100 kg, mine M820 on boost have power variations quickly and i never use it, I have seeted S+ at 80% to have stable assist (few used). I have replaced my 700 Wh battery by an 400 because i never used more than 50% of the 700. With mine M820 i can 30km / 1500 D+, but less quickly than full EMTB. Fot me it's a perfect ebike to ride with my friends whitout assist.
Now my son use it, is wheight is 60 kg, With it it can ride with me with my full ebike and It can climb in boost long time whitout any power variations. rider wheight make a big différency to reach (or not) of the motor temp limith
Now my son use it, is wheight is 60 kg, With it it can ride with me with my full ebike and It can climb in boost long time whitout any power variations. rider wheight make a big différency to reach (or not) of the motor temp limith
Mine has been cracked since almost day 1
Waynemarlow
E*POWAH Elite
Patdam, can I ask you of the cadence of your son, I suspect he has a slower or higher cadence than yourself ? I ask because I think its not the temp setting thats limiting but the way the motor torque sensor is setup. I could repeatidly go into this so called temp problem on one long hill I have which flattens out a small amount about 1/2 way up. I've always blamed the long hill but that same over temp symptom always is on the flatter part.
What it coincides is with me running out of puff and not being able to put enough effort at higher cadences onto the pedals. My normal cadence is up in the high 90's climbing, running out of puff and slightly less torque on the pedals I seem to drop back to about low 90's. I think the torque sensors program curve is dropping back into another part of its torque curve which backs the power back to about that 300 - 350 W's rather than the temp sensor coming into play. I should just buy one of Dado's little gadgets and find out definately.
So how do we overcome this. Well the sensor is programable, I can definatively say that. Let me get a bit more knowledge and how the parameters of the sensor works and I will come back but at this stage on my motor I can change the way the torque sensor works. If anyone who is reasonable computer skilled and has a M820 motor and wants to join in this ride then please PM me.
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hi. i can only said my feeling, not "scientific". I used more RPM than him. But the most important differencies is in the rear sprocket position. He use less teeths than me (To the point i have replaced my 30 teeths front plate by an 32 for him). He feels that motor functioning better when it is under constraints. i had the same feeling when i used it, but on too short torque range. Raison why i use more short demultiplication and quick RPM. But with is low wheight (and young hearth), he can use it on more large torque range (without heating)Patdam, can I ask you of the cadence of your son, I suspect he has a slower or higher cadence than yourself ? I ask because I think its not the temp setting thats limiting but the way the motor torque sensor is setup. I could repeatidly go into this so called temp problem on one long hill I have which flattens out a small amount about 1/2 way up. I've always blamed the long hill but that same over temp symptom always is on the flatter part.
What it coincides is with me running out of puff and not being able to put enough effort at higher cadences onto the pedals. My normal cadence is up in the high 90's climbing, running out of puff and slightly less torque on the pedals I seem to drop back to about low 90's. I think the torque sensors program curve is dropping back into another part of its torque curve which backs the power back to about that 300 - 350 W's rather than the temp sensor coming into play. I should just buy one of Dado's little gadgets and find out definately.
So how do we overcome this. Well the sensor is programable, I can definatively say that. Let me get a bit more knowledge and how the parameters of the sensor works and I will come back but at this stage on my motor I can change the way the torque sensor works. If anyone who is reasonable computer skilled and has a M820 motor and wants to join in this ride then please PM me.
Waynemarlow
E*POWAH Elite
Patdam you and I seem to have similar weights and similar cadences with similar outcomes. I had predicted that you would have a high cadence if my theory is correct.
If I could ask if others using high cadences who are getting similar times where the power to the motor is cut back, if they could note that if they lower the cadence by say dropping a couple of gears and using more effort on the pedals, the motor watts is now back to more normal levels by checking on the watts on your display. Report back please.
If I could ask if others using high cadences who are getting similar times where the power to the motor is cut back, if they could note that if they lower the cadence by say dropping a couple of gears and using more effort on the pedals, the motor watts is now back to more normal levels by checking on the watts on your display. Report back please.
DiReCtX
Member
I also noticed what you are describing
I'm about 90kgs/195 pounds. In S+, averaging around a reported 400 watts of assistance, with a claimed 700wh battery, total bike weight about 44 pounds, Maxxis Minion DHR II + Assegai Exo+ tires, 3000 vertical feet of offroad climbing (around 900m) gets me to 17% battery remaining and dropped down to Eco mode.
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temon10
Well-known member
My XT30 ports is broken after some battery accident. Anyone have this part or have an idea to bypass it??
temon10
Well-known member
how remove the socket?
Hi all,
I have a weird issue with my M820 and original bafang 410Wh battery. I have C245 HMI, and when I am holding power button, it does not turn on. Weirdly, I can reliably turn it on, if i disconnect the HMI, push and hold the power button, and than connect it back. It reliably turns back on. If it is ON all three buttons work OK. Only odd thing was, that one time that I turned it on, CAN communication to the battery was not detected (no voltage reading per cell), and another time I recieved ERR 36.
It used to work OK, but I did wash it yesterday in a CAR wash, (i do it from time to time, and so far I nevere had issues). It worked fine the same day, but the next day it started to have this weird issue.
Any body else experienced something similar?
I have a weird issue with my M820 and original bafang 410Wh battery. I have C245 HMI, and when I am holding power button, it does not turn on. Weirdly, I can reliably turn it on, if i disconnect the HMI, push and hold the power button, and than connect it back. It reliably turns back on. If it is ON all three buttons work OK. Only odd thing was, that one time that I turned it on, CAN communication to the battery was not detected (no voltage reading per cell), and another time I recieved ERR 36.
It used to work OK, but I did wash it yesterday in a CAR wash, (i do it from time to time, and so far I nevere had issues). It worked fine the same day, but the next day it started to have this weird issue.
Any body else experienced something similar?
I installed new HMI DP C080.C display and everything works again as it should. Power ON and OFF is normal again without any ERR 36. It really looks like water damaged it...
It is a little unfortunate that small amount of water damaged C245(even though it has IP X6 rating). I might try to buy only new keypad, to see if it will fix the issue. I went with C080 because it was chipper and has the same functionality. But I still prefer the C245 form factor.
Funnily enough, C080 has IP X7, so it looks like Bafang did work on this.
It is a little unfortunate that small amount of water damaged C245(even though it has IP X6 rating). I might try to buy only new keypad, to see if it will fix the issue. I went with C080 because it was chipper and has the same functionality. But I still prefer the C245 form factor.
Funnily enough, C080 has IP X7, so it looks like Bafang did work on this.
Herculesridesebikes
Member
Hey did you end up finding a solution to this problem? I find that I have a he same issue with the motor cutting out briefly then coming back on. It's usually when I'm in boost mode but I've still had it occasionally happen in other modes.
