80nM of great power - UNTIL-

[Genetics]

I picked up the Black Max - cascade cruiser last year and initially the bike almost pulled my hands from the grips on takeoff (pedal assist). After riding hard for the first 500 miles I noticed a major lag in power , I was riding long range , top speed runs on pedal assist and the watt meter on my LCD was pegged at 999w for upwards 10 to 15 min at a time. The motor is a Bafang RMG06, the ESC (see pic). The battery is a 48v 14.5 ah (Samsung I think) ..

It just seems like I got on it one day and the power is literally cut in half , the battery still tops out at 54v, the resting v is 48v and a used battery v is 45v at resting.…..
‘everything works IE no glitches, no cutting out, Etc, it just feels weak and nobody seems to have an answer. What can I do ? A new ESC perhaps ?

Any input welcome , I searched the threads for an answer but couldn’t find a scenario that matched mine.


Thank you, Darren

 

[Art Deco]

Have you tried some contact cleaner on the connection from battery to controller? After a year that could gum up.

 

[harryS]

No longer getting 999 watts on the LCD? Battery getting tired? I know it still charges to 54.6V, but perhaps it cannot sustain 20+A any more.

 

[Genetics]

Have you tried some contact cleaner on the connection from battery to controller? After a year that could gum up.

Yes sir, I did clean… thank you

 

[Genetics]

No longer getting 999 watts on the LCD? Battery getting tired? I know it still charges to 54.6V, but perhaps it cannot sustain 20+A any more.

I am still getting max watts, I’m sure the 999 is the cutoff for the ESC but yes, I don’t know how to tell if my battery is getting tired, it has less than 50 charges and is fairly new and I’ve never discharged it to a dangerous level and it’s just very slow getting up to speed, it’s definitely lost torque and isn’t anywhere near 80 nM. How do I tell if my battery is getting tired ? I can look this up but I’m wondering if a component in the ESC might of given up the ghost, I read a lot of reviews that talk about these cheap ESC’s the Chinese use in their mass produced e-bikes, something about FETs going out and such , the ESC still functions without any weird glitching , Etc but at a lower lever. Is this something that sounds familiar ?

 

[Lord Zene]

I am still getting max watts, I’m sure the 999 is the cutoff for the ESC but yes, I don’t know how to tell if my battery is getting tired, it has less than 50 charges and is fairly new and I’ve never discharged it to a dangerous level and it’s just very slow getting up to speed, it’s definitely lost torque and isn’t anywhere near 80 nM. How do I tell if my battery is getting tired ? I can look this up but I’m wondering if a component in the ESC might of given up the ghost, I read a lot of reviews that talk about these cheap ESC’s the Chinese use in their mass produced e-bikes, something about FETs going out and such , the ESC still functions without any weird glitching , Etc but at a lower lever. Is this something that sounds familiar ?

I personally wouldn’t put it past them. I’m here kinda looking for the same. I blew up another cheap Chinese no name. I can’t keep them long enough to get that far like you but I don’t use any display and I am constantly switching things redoing other s research I’m sure But it entertains me. My super capacitor/battery combos can get a bit unruly and my blatant disregard or fear of electricity has me keep in covered connections at Times. The last blow up was the hall lines that re 5 v max droooed onto the roughly 64v section of a super cap and basically turned it into one big spot weld. Another $30 in the trash but a good laugh. They are s*it. Period they manipulate the numbers to let’s say 48v 2000 amps. Quick math says 40 amps. But they out on there 2000 w 48-72v. Well you end up at 30 amos and at 48volts it sucks. All the programs that you guys use I’m starting to play with next week. But these 30 dollar controllers are garbage. My suggestion is go big and spend a few bucks. I just bought a 120 amp for 90 and didn’t feel that was bad. If it’s qjLity k don’t know but has to be better than the other. Found some limit busters that are called too. It’s an add on to what you have but gets rid of it tricks the sensors. Warning signs all over it. I ramble I apologize. They were on eBay after torturing all the 2000 watt guys about amps. Finally fell into a little different section. There are guys here that are so much more knowledge able in the rest of it I’m good with the crude sucks part. I’ll find a link to the section on eBay I found today.

 

[Lord Zene]

 

[Lord Zene]

I personally wouldn’t put it past them. I’m here kinda looking for the same. I blew up another cheap Chinese no name. I can’t keep them long enough to get that far like you but I don’t use any display and I am constantly switching things redoing other s research I’m sure But it entertains me. My super capacitor/battery combos can get a bit unruly and my blatant disregard or fear of electricity has me keep in covered connections at Times. The last blow up was the hall lines that re 5 v max droooed onto the roughly 64v section of a super cap and basically turned it into one big spot weld. Another $30 in the trash but a good laugh. They are s*it. Period they manipulate the numbers to let’s say 48v 2000 amps. Quick math says 40 amps. But they out on there 2000 w 48-72v. Well you end up at 30 amos and at 48volts it sucks. All the programs that you guys use I’m starting to play with next week. But these 30 dollar controllers are garbage. My suggestion is go big and spend a few bucks. I just bought a 120 amp for 90 and didn’t feel that was bad. If it’s qjLity k don’t know but has to be better than the other. Found some limit busters that are called too. It’s an add on to what you have but gets rid of it tricks the sensors. Warning signs all over it. I ramble I apologize. They were on eBay after torturing all the 2000 watt guys about amps. Finally fell into a little different section. There are guys here that are so much more knowledge able in the rest of it I’m good with the crude sucks part. I’ll find a link to the section on eBay I found today.

This is a 50 amp and should work fine but how good it is I don’t know.

 

[Haystacks]

The lithium grease has possibly become dry, it goes like crusty toothpaste and hinders the motor. If you are half handy with tools it's fairly easy to diagnose and remedy. I had this with a brand new G060, which i only discovered after they sent a new motor The replacement had what looked like mobilgrease 28 on it, i cleaned the first one up and put mobilgrease 28 on it and it ran - and still does, perfectly.

 

[Genetics]

The lithium grease has possibly become dry, it goes like crusty toothpaste and hinders the motor. If you are half handy with tools it's fairly easy to diagnose and remedy. I had this with a brand new G060, which i only discovered after they sent a new motor The replacement had what looked like mobilgrease 28 on it, i cleaned the first one up and put mobilgrease 28 on it and it ran - and still does, perfectly.

Lithium grease on the motor ? Hmmmm- well I did have the rear hub off for a tube change so while I was in there I pulled the hub from the motor just to take a look and everything looks brand new and nicely lubed. Thank you for the response tho.

 

[ElevenAD]

Maybe constantly running the motor at peak output for 15mins at a time has done some damage? .....also check tire pressure.

 

[harryS]

I've heard about gearless direct drive motors getting so hot that the heat partially demagnetized the motor's magnets. We're talking solder melting off the windings too. and I don't think a G06 will get that hot. Anyway, you a;ready looked inside.

 

[theemartymac]

Maybe constantly running the motor at peak output for 15mins at a time has done some damage? .....also check tire pressure.

The motor should fault out if it overheats as it has a thermistor inside to protect it. Some controllers have one as well, and de-rate power to protect themselves. If you were regularly running high-assist, low-speeds (i.e. hill climbing), I'd suspect the motor first as it can't manage that type of heat for more than a few minutes. If you keep the speed up however, the motor can run fine at high speed for extended periods. I commuted 20km each way with my Bafang 750 hub all last summer (for well over 1000kms) at high assist and high speed. No problems at all unless/until I let my speed fall off too much on the steeper hills and I'd inevitably hit the complete thermal cutout after 5 minutes or so. It resets after several minutes, but might remain de-rated until it cools thoroughly. Different bike of course, but seems like the Bafang family of hardware has quite similar tendencies.

If I kept my speed up relative to the PAS level, it would rip along happily until the battery was dead, but the controller location in the frame and battery case could get very warm/hot. If you were just running running high assist and flat out all the time but keeping a good speed up, I'd lean towards the controller first, as a cheap controller moving a lot of power will definitely be a furnace if contained in the frame. I have not noticed any significant change in my battery performance over the first 18 months, and have completed at least 50-80 charge cycles on each one, and run both of them fast and hard for the majority of cycles.

If you can pop the controller housing cover off, it might be worth looking to see if there is any discoloration or texture change on the wires as they leave the box, as that might indicate a chronic overheating issue? Also, have a good run and then feel the controller directly to see if it's more than uncomfortably warm.

Other than that, it's tough to test anything properly without a motor tester or spare controller.

 

[Genetics]

The motor should fault out if it overheats as it has a thermistor inside to protect it. Some controllers have one as well, and de-rate power to protect themselves. If you were regularly running high-assist, low-speeds (i.e. hill climbing), I'd suspect the motor first as it can't manage that type of heat for more than a few minutes. If you keep the speed up however, the motor can run fine at high speed for extended periods. I commuted 20km each way with my Bafang 750 hub all last summer (for well over 1000kms) at high assist and high speed. No problems at all unless/until I let my speed fall off too much on the steeper hills and I'd inevitably hit the complete thermal cutout after 5 minutes or so. It resets after several minutes, but might remain de-rated until it cools thoroughly. Different bike of course, but seems like the Bafang family of hardware has quite similar tendencies.

If I kept my speed up relative to the PAS level, it would rip along happily until the battery was dead, but the controller location in the frame and battery case could get very warm/hot. If you were just running running high assist and flat out all the time but keeping a good speed up, I'd lean towards the controller first, as a cheap controller moving a lot of power will definitely be a furnace if contained in the frame. I have not noticed any significant change in my battery performance over the first 18 months, and have completed at least 50-80 charge cycles on each one, and run both of them fast and hard for the majority of cycles.

If you can pop the controller housing cover off, it might be worth looking to see if there is any discoloration or texture change on the wires as they leave the box, as that might indicate a chronic overheating issue? Also, have a good run and then feel the controller directly to see if it's more than uncomfortably warm.

Other than that, it's tough to test anything properly without a motor tester or spare controller.

WOW- good stuff ! Ok, yeah I’ve got a couple things going through my mind, #1 after a few weeks of riding it I’ve just gotten used to it and all of this is in my head. When I first bought the bike i was actually a little nervous it had so much power ! I guess initially I didn’t expect electric to have that kind of power. #2 the Esc is defective and I need to do as you’ve suggested and get another ESC and install it to see if there’s any difference . They are fairly cheap but are they all pretty much the same ? I’ve looked for a name on the ESC and can’t find a name or manufacturer, I’ve even searched the controller number and to no avail.

So- bottom line if everything checks out good I’ll just purchase a new pack and go from 48v to 52v and get a little extra power that way, any suggestions for cheap upgrade ?
thank you

 

[Genetics]

I've heard about gearless direct drive motors getting so hot that the heat partially demagnetized the motor's magnets. We're talking solder melting off the windings too. and I don't think a G06 will get that hot. Anyway, you a;ready looked inside.

Yes, thank you for your post, I did have the motor out and everything looks pristine , no discoloration of magnets, no indication of overheating, Etc. I fly RC and am quite familiar with the issues associated with overheating brushless motors, I’ve overpropped a motor or two in my day and YES- they do deteriorate. Anyhow- thanks again for your suggestions .

 

[Genetics]

The motor should fault out if it overheats as it has a thermistor inside to protect it. Some controllers have one as well, and de-rate power to protect themselves. If you were regularly running high-assist, low-speeds (i.e. hill climbing), I'd suspect the motor first as it can't manage that type of heat for more than a few minutes. If you keep the speed up however, the motor can run fine at high speed for extended periods. I commuted 20km each way with my Bafang 750 hub all last summer (for well over 1000kms) at high assist and high speed. No problems at all unless/until I let my speed fall off too much on the steeper hills and I'd inevitably hit the complete thermal cutout after 5 minutes or so. It resets after several minutes, but might remain de-rated until it cools thoroughly. Different bike of course, but seems like the Bafang family of hardware has quite similar tendencies.

If I kept my speed up relative to the PAS level, it would rip along happily until the battery was dead, but the controller location in the frame and battery case could get very warm/hot. If you were just running running high assist and flat out all the time but keeping a good speed up, I'd lean towards the controller first, as a cheap controller moving a lot of power will definitely be a furnace if contained in the frame. I have not noticed any significant change in my battery performance over the first 18 months, and have completed at least 50-80 charge cycles on each one, and run both of them fast and hard for the majority of cycles.

If you can pop the controller housing cover off, it might be worth looking to see if there is any discoloration or texture change on the wires as they leave the box, as that might indicate a chronic overheating issue? Also, have a good run and then feel the controller directly to see if it's more than uncomfortably warm.

Other than that, it's tough to test anything properly without a motor tester or spare controller.

Hello again.
I just wanted to thank you for your input and I did as you suggested and removed the cover plate to the esc and took it for a hard ride, the esc barely made warm to the touch and everything else appears to be in order, my guess is that I have gotten used to the power….. It reminds me of an old hot rod I bough about 35 years ago, when I first bought it I was terrified of the raw horsepower (about 350 horses) and that was a lot for a 20 year old kid, needless to say that power was nothing after the first 6 months of being my daily driver.. bottom line is I’m going to need to hop the bike up, my thoughts are a 52 v battery instead of the stock 48 v, hopefully that gives me the little extra umph I’d like to have….. thanks again

 

[theemartymac]

A 52V battery by itself likely won't make a noticeable difference. It's not like the jump from 36v to 48v which is a boost of 25%. Your only slightly notching your way up by just over 10%, and the controller may still be a bottleneck anyway. The big reasons for 52V systems is that they remain above 48 volts for longer, so you don't notice a decline in power output around the 50% charge point like you can with a 48V battery.

It's just a reality that the 750 Bafang Hubs are not monsters. Functional power for sure, and plenty fast enough for most users, but they are seldom described as overly "powerful". They have known weaknesses in hard climbing, and simply pale in comparison next to a nice mid-drive. Add 20" wheels and depending on the windings used, you could be very speed limited. There are also the versions that actually use 500W motor cores (see Boltons videos on the Rad 500w Series), and simply try and overvolt the controller. That only helps a little, as he shows in his comparison testing.

You may be able to modify the hidden controller settings through the display, or Bafang programming software for a bit more punch, and you could certainly buy an upgraded controller to push the motor up to or even over 1500w and 30+ amps. There have been a number of folks who have done that - with the increased risk of premature failure of course. I'd try and demo a new 750 hub bafang bike at your local bike shop and see if it really is that different, or if you truly have just acclimated to the power.

 

[retiredNH]

Note that hub drives must work over a much broader RPM range than a mid drive. This means they're inherently less efficient, not in power use, but in having optimal specs, including torque, over the broad RPM range.

 

[Genetics]

A 52V battery by itself likely won't make a noticeable difference. It's not like the jump from 36v to 48v which is a boost of 25%. Your only slightly notching your way up by just over 10%, and the controller may still be a bottleneck anyway. The big reasons for 52V systems is that they remain above 48 volts for longer, so you don't notice a decline in power output around the 50% charge point like you can with a 48V battery.

It's just a reality that the 750 Bafang Hubs are not monsters. Functional power for sure, and plenty fast enough for most users, but they are seldom described as overly "powerful". They have known weaknesses in hard climbing, and simply pale in comparison next to a nice mid-drive. Add 20" wheels and depending on the windings used, you could be very speed limited. There are also the versions that actually use 500W motor cores (see Boltons videos on the Rad 500w Series), and simply try and overvolt the controller. That only helps a little, as he shows in his comparison testing.

You may be able to modify the hidden controller settings through the display, or Bafang programming software for a bit more punch, and you could certainly buy an upgraded controller to push the motor up to or even over 1500w and 30+ amps. There have been a number of folks who have done that - with the increased risk of premature failure of course. I'd try and demo a new 750 hub bafang bike at your local bike shop and see if it really is that different, or if you truly have just acclimated to the power.

Thank you for the info sir, you have given me all I need to know …. I think I’ll close this thread and just deal with the bike the way it is, she rides nice, she’s plenty fast at 25 mph I don’t feel the need for more speed, it’s really the torque I wanted but I might have to save up and ether make myself a mid drive or just spend 3,000$ for one of those 3,000w bikes from alibaba. BTW- What fo you ride ?

 

[theemartymac]

Thank you for the info sir, you have given me all I need to know …. I think I’ll close this thread and just deal with the bike the way it is, she rides nice, she’s plenty fast at 25 mph I don’t feel the need for more speed, it’s really the torque I wanted but I might have to save up and ether make myself a mid drive or just spend 3,000$ for one of those 3,000w bikes from alibaba. BTW- What fo you ride ?

I have 2 right now. A Rize X - 750w Hub, and a Rize RX Pro - 1000w Ultra Mid-drive. I love the hub, but it just doesn't climb well enough for my west coast riding (I'm a big guy, and carry lots to work) so the Ultra is my main commuter. Gobs of power and the benefits of that mid-drive gearing. If I could get that kind of power out of a hub though (without going too custom), I'd be all over it. The hub is just so easy to ride, and it's my preferred ride in the city for errands and casual cruising.