Motor change-out

[harryS]

Hub motors are pretty simple. Simple enough that more than a few production workers have probably walked off the floor of a motor shop with the plans in their heads, and set up a competitor across the street.

There's no electronics. Just three magnetic sensor chips. The motors have to be wound by hand because no one wants to build a robot to wrap them wires around. The machines needed to cut the metal were themselves copies of copies. Probably everyone and his sister can open a motor shop, but Bafang is the market leader.

How fast a motor can spin depends on how they wrap the windings. Its power will depend on the number of magnets as well as the size of the magnets. Big DD motors get their wattage ratings because they have more magnets plus more metal mass to dissipate waste heat. The winding construction is a trade-off. A motor that can spin faster has less torque for starting, and vice versa.

Geared motors are smaller, with the gears multiplying the lower torque. Typical gear ratios are 4:1, so they spin 4X faster. Some smaller geared motors are like 12:1.

 

[mjorg]

In any electric vehicle, the power and longevity are more than just changing a motor. It only uses what energy is sent to it through the controller and the programmed rate. A controller will burn up far easier than a motor. A programmable controller is what you need before a new motor.

The plug seems to be another issue. Lord knows what the controller electronics are when they are buried into the frame. I don't want to stick a box on it.

Hub motors are pretty simple. Simple enough that more than a few production workers have probably walked off the floor of a motor shop with the plans in their heads, and set up a competitor across the street.

There's no electronics. Just three magnetic sensor chips. The motors have to be wound by hand because no one wants to build a robot to wrap them wires around. The machines needed to cut the metal were themselves copies of copies. Probably everyone and his sister can open a motor shop, but Bafang is the market leader.

These bikes have been around for years now. They need to start standardizing parts, like the plugs and controllers. I would like a Bafang. But it's looking like it would be a $400-$500 gamble at this point. To me these motors are amazing technology that the Chinese should be proud they are producing so inexpensively. I can see electric cars based on these motors in a four wheel drive configuration. Imagine a $5,000 electric car.

 

[mjorg]

Hub motors are pretty simple. Simple enough that more than a few production workers have probably walked off the floor of a motor shop with the plans in their heads, and set up a competitor across the street.

There's no electronics. Just three magnetic sensor chips. The motors have to be wound by hand because no one wants to build a robot to wrap them wires around. The machines needed to cut the metal were themselves copies of copies. Probably everyone and his sister can open a motor shop, but Bafang is the market leader.

How fast a motor can spin depends on how they wrap the windings. Its power will depend on the number of magnets as well as the size of the magnets. Big DD motors get their wattage ratings because they have more magnets plus more metal mass to dissipate waste heat. The winding construction is a trade-off. A motor that can spin faster has less torque for starting, and vice versa.

Geared motors are smaller, with the gears multiplying the lower torque. Typical gear ratios are 4:1, so they spin 4X faster. Some smaller geared motors are like 12:1.

My motor must be DD. But it has better low end than speed. Actually the power band is perfect relative to a 20 mph limit. I wouldn't want a mid-drive.

 

[Off road all day]

My question is why you want to change out a working motor out for another one which seems just because of the name?
Yes i have fallen in love with the Bafang mid drive, but i'm going to build my ultimate E-bike over time, on a budget. Not by name

 

[erider_61]

The motors have to be wound by hand because no one wants to build a robot to wrap them wires around.

Robotic electric motor winders have been around for years

http://jenlor-samatic.com/

 

[harryS]

Not at the place where I got the motor for my first ebike conversion, The factory website pic shows a bunch of workers winding motors.

 

[mjorg]

My question is why you want to change out a working motor out for another one which seems just because of the name?
Yes i have fallen in love with the Bafang mid drive, but i'm going to build my ultimate E-bike over time, on a budget. Not by name

Just got into this hobby. I don't know what I have yet. If I find that I can get much better performance with a better motor, I want it.

 

[AHicks]

Still struggling with what it is you're trying to improve. How fast will you be going when you notice this "much better performance"?

These bikes are all about compromise. There's only so much power available from your battery and controller, and it sounds like change there is not on the table. So with that in mind, you need to make a decision to replace all that -OR- compromise with your performance expectations, and try to enhance what you have going on at relatively low speeds, or higher speeds. Because of your power limitations, you need to steal from one side to add to the other. You cannot improve both high and low speed performance, without more power.....

 

[mjorg]

I understand what you are saying. I wonder about the quality of this bike and if it performs as well as a more quality product. Bafang may just be a better motor and give me more run time. Battery life, miles per charge is the most important thing for me. I live in a huge metroplex which I want to explore. Many more miles that one battery charge will presently allow me. I'm purchasing a second battery and when the time comes I'll have my batteries rebuilt to a higher performance capability. After I upgrade the batteries I planned on looking hard at the motor, just because the cost of a motor is less than a battery rebuild. I just may keep this one. Thanks for educating me about the power characteristics of e-bikes.

 

[AHicks]

If I may, I'd suggest riding the heck out of what you have. Don't stress over the "quality" of this bike. After a while sore spots may become clear. At that point, go to work on those....

Meanwhile, keep reading and asking questions..... but don't change anything until you have a clearer picture of what you have now, and exactly what options you may have available.

Part of the bike's performance is about you. Your skill set regarding maximizing battery economy (by keeping the bike in the right gear and PAS level for the conditions you're riding in) will likely increase quite a bit in those first few hundred miles.

Noteworthy maybe, is the fact range and hill climbing power were my early e-bike concerns. Hill climbing power can never be good enough for a lot of us, but that range issue pretty much disappeared after realizing my butt's range was already less than the battery's....

 

[mjorg]

I am going to do exactly as you advise. Thank you for taking the time to advise me. I really appreciate it. Lots of others where here to help me too. I like this place. In just this one thread, I understand the technological big picture.

This bike is as good as I could ever expect it to be for the money. Maybe it's just hard to believe I got such a good deal. I love this thing. I'm into e-biking all the way.

 

[john peck]

In any electric vehicle, the power and longevity are more than just changing a motor. It only uses what energy is sent to it through the controller and the programmed rate. A controller will burn up far easier than a motor. A programmable controller is what you need before a new motor.

I'm wishing now there was a way to fit that 25 amp controller they sent into the CCS. I think it would be better suited to this wheel, & pre-programmed
for the display that came with it.( not that my display wasn't getting a bit wacky before the swap, moisture) I think I'd have better low speed
performance with the new controller.