Need advice on what to do.

[JR69]

Okay, I've read a lot of posts here and other places and seems like the best way to solve my problem is to replace the controller and display however, I'm new to this and never posted so I figured I'd ask the experts here.

I have a new 20in fat tire ebike, generic chinese brand but quality. It has a Bafang G062 750W motor, 48v/20ah battery, 22amp controller and NC-81f display. Out of the box, with the wheel off the ground it's give me 19mph. It does peak for a second at 21 but slows. I went into the menu and the top speed was set at 65. All of the other parameters seemed "normal", 48v, 22ah controller, 22inch wheels etc. I changed the wheel size and it was the same speed. Obviously, there is a speed limiter and I'm assuming it's the controller. The attached photo is basically what the controller looks like.

So back to the title of my post, should I just replace the controller? Is that is what is limiting the motor? I know a 22ah controller can do more than 19mph, so what gives?

Thanks all for any advice, thoughts.

 

[amberwolf]

Is it exactly the same speed offground as when riding? If so, it's limited in the controller hardware from the factory. The display may let you set a speed limit but the controller disregards this due to the factory limit.

You'd probably have to replace the controlelr/display set with a new non-limited one to fix that.


If it is slower onground than off (usually by around 10-20%), then probably the motor is wound so that at the voltage of the system it's just not capable of going any faster. In a larger wheel it would go faster, proportionally, as long as the power required for that speed with the squishier higher-rolling-resistance tires is available, and the battery can supply that power without sagging in voltage (which will reduce the speed of the motor). .


Side note: A(mps) and Ah(amphours) are two completely different things. The first one is current, and the second is capacity. Just so you use the right terms to get the info you want across, and understand what they mean when you see them.

 

[JR69]

Is it exactly the same speed offground as when riding? If so, it's limited in the controller hardware from the factory. The display may let you set a speed limit but the controller disregards this due to the factory limit.

You'd probably have to replace the controlelr/display set with a new non-limited one to fix that.


If it is slower onground than off (usually by around 10-20%), then probably the motor is wound so that at the voltage of the system it's just not capable of going any faster. In a larger wheel it would go faster, proportionally, as long as the power required for that speed with the squishier higher-rolling-resistance tires is available, and the battery can supply that power without sagging in voltage (which will reduce the speed of the motor). .


Side note: A(mps) and Ah(amphours) are two completely different things. The first one is current, and the second is capacity. Just so you use the right terms to get the info you want across, and understand what they mean when you see them.

Yes, it's the same speed. I suspected that the controller is limiting it based on the motor ramps up quickly and they you can hear it back down. I wouldn't think the motor is wound any differently than any other Bafang G062 750w motor, which I've read can peak at 1200w.

As for Ah and A, yes I know the difference, it was just a typo, but thank you for pointing that out.

Attached is my current controller.

 

[glennb]

If your controller model number ended in an “F” you’d definitely be able to reprogram it with new firmware, but I’m not sure about ones ending in “E”. Still worth checking out. “high stance cola” wrote the code and should be able to help you. Otherwise you’re looking at a hundred bucks for a new Lishui controller.

 

[JR69]

If your controller model number ended in an “F” you’d definitely be able to reprogram it with new firmware, but I’m not sure about ones ending in “E”. Still worth checking out. “high stance cola” wrote the code and should be able to help you. Otherwise you’re looking at a hundred bucks for a new Lishui controller.

Wow, no kidding? I assume "high stance cola" is a member here? Thank you.

 

[glennb]

Yep, username “stancecoke”.

Lishui also have a free programming tool you can download. But you’ll be unable to use it if your controller’s locked.

The controllers ending in “F” are unlocked, as far as I know, but others might also be. I’ve never had one in my hands with an “F” to try it out, and there was little point bothering to try it with the ones I’ve had access to, because they needed to be restricted to 25km/h.

 

[stancecoke]

The controllers ending in “F” are unlocked

The F on the label stands for FOC (field orientation control) in the old Lishui FOC controller generation. It has nothing to do with "locked" or "unlocked". Lishui has cheap square wave controllers also (e.g. in the Yose-Power sets), the EBiCS firmware is only suitable for the FOC controllers.

You can flash the EBiCS firmware to your controller to get rid of the speedlimit. Two concerns. First: Check, if your motor connector has 9 pins. With less pins the motor is "sensorless" and the sensorless branch of EBiCS has not the maturity to give a full recommandation to use it. Second; I don't know the display NC-81f, so I don't know, if it uses a protocol that is supported by EBiCS.

Home

Free FOC firmware for Lishui E-Bike-Controllers. Contribute to EBiCS/EBiCS_Firmware development by creating an account on GitHub.

github.com

regards
stancecoke

 

[glennb]

Thanks for the clarification.

So, no F, no EBiCS.

And there’s no clues in model numbers as to whether programming via the lishui tool is possible?

Program Downloader

This page includes an instruction video and a RAR file for customizing your controller program.The program is designed to be used by brand owners, bike manufacturers for development and research only.

www.lsdzs.com

 

[stancecoke]

So, no F, no EBiCS.

not that easy The new generation (with green labels) are mostly FOC controllers.
The photo of @JR69 seems to show a square wave controller with a STM32F031 processor.
There is a brand new project for them:

GitHub - stancecoke/Lishui9FET

Contribute to stancecoke/Lishui9FET development by creating an account on GitHub.

github.com

In this project I provide a compiled hex file in the releases that can be flashed to the controller by a STLink-V2. The setup of the individual system is done by the display.
It's just annoying that the controllers are potted, so you have to do some digging to get access to the SWD-port.

regards
stancecoke

 

[glennb]

That sounds excellent, like all your projects.

I’ll try it next time a lishui lands in my lap.

Hopefully one day lishui will provide better access to their products by developing retail channels.

LR69, are you going to try it out?

 

[JR69]

The F on the label stands for FOC (field orientation control) in the old Lishui FOC controller generation. It has nothing to do with "locked" or "unlocked". Lishui has cheap square wave controllers also (e.g. in the Yose-Power sets), the EBiCS firmware is only suitable for the FOC controllers.

You can flash the EBiCS firmware to your controller to get rid of the speedlimit. Two concerns. First: Check, if your motor connector has 9 pins. With less pins the motor is "sensorless" and the sensorless branch of EBiCS has not the maturity to give a full recommandation to use it. Second; I don't know the display NC-81f, so I don't know, if it uses a protocol that is supported by EBiCS.

Home

Free FOC firmware for Lishui E-Bike-Controllers. Contribute to EBiCS/EBiCS_Firmware development by creating an account on GitHub.

github.com

regards
stancecoke

That's great, thank you, I appreciate all of that information you provided. The NC-81f is a great "looking" display but the menu is cumbersome. What I will do @glennb is replace the controller and display, as I hate square wave controllers, too jerky. I'm new to this but I did purchase a controller (that I hope will work with my Bafang motor) and give it a try. I do see many controllers that are labeled specific to Bafang G062 motors. It looks like those consolidate the wire harnesses together, much like the one I have, like the one in my first post. Any advice will be appreciated.

But I love to tinker so what I might do is to use this info to play around with the Lishui I pull.

 

[JR69]

I have another question. Here are my connectors. Is the blue 4pin for the lights? The controllers I've been looking at don't have the blue one, they all seem to have the two 6v connectors for the lights.

 

[JR69]

The Red motor connector is a 11pin L1121

 

[JR69]

Well, I ordered a 30A unlocked controller and it didn't work. I had an issue with the signal connector but finally got it to fit. I opened up the Lishui controller and wow, it's totally potted, I mean, it's filled with potting material. Is that normal??? So unless I destroy it I'm stuck with the original controller and speed at 20.

I'm new to ebikes but what I've learned is that there is absolutely NO stardardization, not even when it comes to the types of cable connectors used. AND if they are the same, some have male connectors, some have female connectors for the devices. etc. pretty crazy and totally frustrating.

 

[Chalo]

So unless I destroy it I'm stuck with the original controller and speed at 20.

Well, what I'd do is replace everything that's standing in the way of what I wish to do with my own bike. Motors don't care, throttles and sensors don't care. Display and controller should be enough swaps to accomplish what you want.

This is why I recommend DIY conversions over complete e-bikes. Imagine the pushback if car and motorcycle manufacturers got this deep into limiting what folks could physically do with their own vehicles. And those bigger vehicles actually pose a threat to public safety, whereas bikes really don't.

So I am in favor of unrestricted e-bikes (with mass and power limitations), but motor vehicles that are geofenced and electronically governed to the local speed limit.

 

[JR69]

Yeah, it's pretty crazy. And I don't even want go 40mph, I just don't want to be limited to 20 throttle only and even PAS is max 26. What's the point of putting a 750W or 1000W motor in the bike?

I don't have a choice other than to leave it as I've already spent $$$ on things that are not usable.

 

[LewTwo]

... Imagine the pushback if car and motorcycle manufacturers got this deep into limiting what folks could physically do with their own vehicles. And those bigger vehicles actually pose a threat to public safety, whereas bikes really don't. ....

They would likely charge extra for those 'safety features' as well

 

[Chalo]

Yeah, it's pretty crazy. And I don't even want go 40mph, I just don't want to be limited to 20 throttle only and even PAS is max 26. What's the point of putting a 750W or 1000W motor in the bike?

Well, they understand marketing (more=better), and they probably know a thing or two about their buyers. At my highest body weight, it probably would have taken a 1000W (actual at the wheel) motor to hold 26mph on flat pavement. Still, that didn't make my kinetic energy a public safety issue.

I just rehabbed a Class 3, 28 mph e-bike at the community bike shop where I work. It is only a 350W nominal motor, so it would take some committed pedaling to actually get to 28.

 

[JR69]

Funny, but I get your point. Other than flashing the firmware on the controller (I thought about it but worried I'd brick it), I'd have to rewire the whole bike which I'm not prepared to do yet.

 

[nicobie]

If you pay attention to what wire goes where, it's not all that hard to do. Just need a cheap soldering iron and some connectors from HobbyKing. Give it a go. It's fun.

 

[JR69]

If you pay attention to what wire goes where, it's not all that hard to do. Just need a cheap soldering iron and some connectors from HobbyKing. Give it a go. It's fun.

Yeah, I'm not shy about doing that and can solder, that's not the issue, it's finding the connectors just in case I screw up, I'd like to have another one and I can't find them.

 

[glennb]

So …

You have a lishui with correct connectors, but it’s speed restricted and you’re concerned about bricking it while installing new firmware?

And you have a new non-restricted controller with incorrect connectors?

If so, you could try stancecoke’s firmware.

If the firmware goes well, problem solved.

If the firmware goes badly, you can cut the connectors off the lishui to splice onto the new controller.

If the splicing goes well, problem solved.

If the splicing goes badly, you can redo all the connectors on both sides.

Even if you mess that up, you can buy another controller, ideally an unrestricted lishui with matching connectors.

I’d be surprised if it comes to that. Plenty of people have had to remove potting to install new firmware, and all seemed to succeed at it.