YZ85 QS138 V3 Battery selection

[72V]

Hello, I am new to electric bikes. However, I just started a build using a YZ85 frame. I have purchased the qs138 V3 70h, and the 72530 fardriver controller. My questions is what battery should I go with? From what I have read the 72530 can handle a max of 330amp input. So I was looking at batteries from Amroge with 72v 200amp - 350amp continuous and around 40ah - 50ah. I want to get the most power and range battery that will fit the bike. However, I do not want to purchase a higher amp output battery than the rest of my system (controller and motor) can handle. Any feedback would be greatly appreciated!

below is a links to the battery options I am considering. If you select the battery it will show all 3 options
40AH/ 2880WH/ 250AMP(350AMP PEAK))42AH/ 3024WH/ 350AMP(450AMP PEAK))50AH/ 3600WH/ 300AMP(400AMP PEAK))

Amorge 72v 40ah 250amp 42ah 350amp 50ah 300amp Lithium Battery Pack With Ant Bluetooth Bms - Buy 72v 40ah 250amp 42ah 350amp 50ah 300amp Lithium Battery 72v 40ah 250amp 42ah 350amp 50ah 300amp Lithium Battery Pack With Ant Bluetooth Bms 72v 40ah 250a

Amorge 72v 40ah 250amp 42ah 350amp 50ah 300amp Lithium Battery Pack With Ant Bluetooth Bms - Buy 72v 40ah 250amp 42ah 350amp 50ah 300amp Lithium Battery 72v 40ah 250amp 42ah 350amp 50ah 300amp Lithium Battery Pack With Ant Bluetooth Bms 72v 40ah 250amp 42ah 350amp 50ah 300amp Lithium Battery...

www.alibaba.com

 

[72V]

So I ended up purchasing a battery from Amorge, "42AH/ 3024WH/ 350AMP(450AMP PEAK))" and now after I ordered it I'm wondering if maybe I bought a battery that's too powerful for the controller I have (fardriver 72530). Does anyone know if this will be too much power? Or can I dial back the voltage with the BMS? Any help would be appreciated. Thanks

 

[j bjork]

The battery can never be "too powerful" it can only be too weak to deliver the amps the controller wants, or powerful enough.
The bms cant affect what voltage or amperage flows in the system, it can only let it flow or cut.
You set the amps you want in the controller, and the battery is 72v for a 72v controller. So it looks like a good match to me.

 

[72V]

The battery can never be "too powerful" it can only be too weak to deliver the amps the controller wants, or powerful enough.
The bms cant affect what voltage or amperage flows in the system, it can only let it flow or cut.
You set the amps you want in the controller, and the battery is 72v for a 72v controller. So it looks like a good match to me.

Thanks for the help. I have another question.

I bought the qs138 just because I saw a lot of people using them online, and they have the gear reduction. However, now im starting to wonder if I should have went with the qs165.

Would my controller and battery be sufficient to run with the 165? If so im thinking maybe I buy 165 and keep the 138 for another project.

 

[72V]

The battery can never be "too powerful" it can only be too weak to deliver the amps the controller wants, or powerful enough.
The bms cant affect what voltage or amperage flows in the system, it can only let it flow or cut.
You set the amps you want in the controller, and the battery is 72v for a 72v controller. So it looks like a good match to me.

Or the QS180

 

[j bjork]

Would my controller and battery be sufficient to run with the 165? If so im thinking maybe I buy 165 and keep the 138 for another project.

What do you mean with sufficient?
It is probably not powerful enough to get max out of any of the motors you mentioned, possibly the qs 165. If that is the narrow, surron like motor you mean?
Then it is the question about position sensors, I suppose the controller is for hall sensors? (as far as I know the qs 138 still has hall)
I think you can choose hall or encoder on the qs 165, in that case you can drive it.

Qs 180? I dont see the point to put one in an 85cc dirtbike chassi, unless it is for dragracing or something. Even if you could drive it with your controller, what would be the point? (If you get an early model with hall sensors you can). I wouldnt bother with Qs180 under 1000 phase amps unless it is for something heavy to pull, like in a boat or something. It is a big motor for big power.

If you are after more power I would keep the qs 138 and get a more powerful controller.

 

[72V]

My goal is to build something crazy fast. However, I've never even rode an e-bike before let alone something mid-drive with a big motor and high-output controller, so I have no idea what to expect. (other than what I've saw online) The closest thing I have ridden thats electric would be hilboy scooter lol. I guess I should have done a little more research before buying shit willy-nilly. The day I decided I wanted to build this bike I watched youtube for about 2 hours and then started ordering shit. Nearly all the build videos with 85cc or 250cc frames were using the 138 so that's what I ordered. Unlike most people who ease into a hobby and maybe start with something slower or more cost-effective, I have a habit of taking shit to the extreme right from the jump. However since Ive already ordered all this stuff and due to the long lead times, I'll probably just build the bike with what I ordered and if it doesn't scare the shit out of me, then I'll sell it, and build another bike with a larger frame that can fit larger motor and battery.

 

[72V]

Do you have any experience with the 138 v3? I was looking at it today and noticed a gap between the outer cover and the motor housing. I read that they have changed these motors a few times over the years with one change having something to do with better ventilation for that area. Do you know if this is by design, or perhaps is missing part of the gasket?

 

[72V]

Few more pics. I finally got the motor and controller. Mt 12" supermoto wheels and tires should get delivered tomorrow along with all new plastics. The only thing Ill be waiting on after tomorrow is the battery.

 

[72V]

Got the mini motos, 250mm big break kit, and plastics delivered today. Still waiting on the new black gas tank, seat cover, and battery.

 

[72V]

What do you mean with sufficient?
It is probably not powerful enough to get max out of any of the motors you mentioned, possibly the qs 165. If that is the narrow, surron like motor you mean?
Then it is the question about position sensors, I suppose the controller is for hall sensors? (as far as I know the qs 138 still has hall)
I think you can choose hall or encoder on the qs 165, in that case you can drive it.

Qs 180? I dont see the point to put one in an 85cc dirtbike chassi, unless it is for dragracing or something. Even if you could drive it with your controller, what would be the point? (If you get an early model with hall sensors you can). I wouldnt bother with Qs180 under 1000 phase amps unless it is for something heavy to pull, like in a boat or something. It is a big motor for big power.

If you are after more power I would keep the qs 138 and get a more powerful controller.

What's the difference between hall sensor and encoder in terms of performance? Doesn't that just give feedback regarding throttle position. I use stepper motors with encoders on my CNC machine to ensure accuracy and to make sure they don't miss any steps. But I guess I don't understand why that would be necessary for this application. If I do upgrade the controller, what controller would you recommend to get the most out of the 138 and the 72v 350a / 450a battery?

 

[Hummina Shadeeba]

Got the mini motos, 250mm big break kit, and plastics delivered today. Still waiting on the new black gas tank, seat cover, and battery.

That gap you show of the motor is how it’s supposed to be with the new version of that motor.
The motor has more than enough power/torque. Ur more so limited by ur controller, then the battery. The motor will do more amps and voltage than the controller or battery will put out. I like the 3shul cl700. It’ll put out pretty much the max current and voltage the motor can do

I’m keeping it in the backyard till I get my license.

 

[72V]

That gap you show of the motor is how it’s supposed to be with the new version of that motor.
The motor has more than enough power/torque. Ur more so limited by ur controller, then the battery. The motor will do more amps and voltage than the controller or battery will put out. I like the 3shul cl700. It’ll put out pretty much the max current and voltage the motor can do

I’m keeping it in the backyard till I get my license.

Nice build, curious what the doner bike is, and what motor and controller are you using? What kind of performance are you getting out of it? Thanks for the info!

 

[Hummina Shadeeba]

Tao db27 bike. 3shul cl1000.

It has way more torque n speed than I’m comfortable using and I don’t go full throttle or full speed. The 3shul cl700 is pretty close and I have another clone bike with it. 126v full charge.
(Selling the clone for 2400$).

 

[72V]

You have any videos of it ?

Did you build the battery yourself?

Looks like a great option for a doner bike, lots of room for a battery

 

[Hummina Shadeeba]

You have any videos of it ?

Did you build the battery yourself?

Looks like a great option for a doner bike, lots of room for a battery

No video. No video and now it sits in the yard till I get my license n the cops pulled me over. It could’ve been really bad but “the system was down” and they were unable to tow and impound.
I built the battery with batteryhookup cells. It’s 4.5 watthours with ion cells and 2.5 with lifepo4

I bought the bike new and stripped it.

 

[j bjork]

What's the difference between hall sensor and encoder in terms of performance? Doesn't that just give feedback regarding throttle position. I use stepper motors with encoders on my CNC machine to ensure accuracy and to make sure they don't miss any steps. But I guess I don't understand why that would be necessary for this application. If I do upgrade the controller, what controller would you recommend to get the most out of the 138 and the 72v 350a / 450a battery?

The difference is the number of pulses per revolution. In your motor with 5 pole pairs and 3 hall sensors you get 15pulses.
There are different encoders, but they have a few 1000 pulses per revolution.
The result is better precision in the timing at low rpm, so it should give better torque and smoother start. I cant say by how much.

I think your motor can take 700-800 phase A before it saturates too much, so I would go with a controller that can do that.
And if your battery can provide 400 A, the controller should handle that as well.
I am thinking something like 3shul c/cl1000 or fardriver 72/96850. The lover voltage options will probably have better efficiency, but if you want more power it can be nice to be able to go with higher voltage.

Personally I think it will be plenty of power in a 85cc chassis anyway if any of these options is set up properly.

 

[72V]

The difference is the number of pulses per revolution. In your motor with 5 pole pairs and 3 hall sensors you get 15pulses.
There are different encoders, but they have a few 1000 pulses per revolution.
The result is better precision in the timing at low rpm, so it should give better torque and smoother start. I cant say by how much.

I think your motor can take 700-800 phase A before it saturates too much, so I would go with a controller that can do that.
And if your battery can provide 400 A, the controller should handle that as well.
I am thinking something like 3shul c/cl1000 or fardriver 72/96850. The lover voltage options will probably have better efficiency, but if you want more power it can be nice to be able to go with higher voltage.

Personally I think it will be plenty of power in a 85cc chassis anyway if any of these options is set up properly.

So the controller I ordered is the 72530, I read that it has a max line amps of 350. Does this mean that the battery I ordered with a 450a peak discharge could damage the controller? Or is there a way to program the controller so that it only accepts the 350a that its rated for, or perhaps this could be achieved with the BMS? The BMS is supposed to have Bluetooth and an app you can download, I just don't know what kind of functionality it has. Or should I just go ahead and order one of the larger controllers that you mentioned? I already welded mounting brackets for the 72530, and it was a pretty tight fit. I looked up the other controllers you mentioned and they are even larger than the 72530, so if I can use the 72530 without damaging it, I want to at least give it a try. However, if this isn't safe or would for sure damage the controller I'll go ahead and get a new one ordered so can figure out the mounting before my battery arrives.

 

[j bjork]

You should probably take it a little easy and not try to get the max out of everything, instead try to get a basic understanding of how things work and take it from there. No, the battery wont damage the controller.. There must be hundreds of these threads, I answered the same thing a few days ago.

 

[Hummina Shadeeba]

So the controller I ordered is the 72530, I read that it has a max line amps of 350. Does this mean that the battery I ordered with a 450a peak discharge could damage the controller? Or is there a way to program the controller so that it only accepts the 350a that its rated for, or perhaps this could be achieved with the BMS? The BMS is supposed to have Bluetooth and an app you can download, I just don't know what kind of functionality it has. Or should I just go ahead and order one of the larger controllers that you mentioned? I already welded mounting brackets for the 72530, and it was a pretty tight fit. I looked up the other controllers you mentioned and they are even larger than the 72530, so if I can use the 72530 without damaging it, I want to at least give it a try. However, if this isn't safe or would for sure damage the controller I'll go ahead and get a new one ordered so can figure out the mounting before my battery arrives.

What bms you using? If you’re not using a bms for discharge it’s worth adding a fuse between battery and controller and sometimes controllers fail and become a short.

 

[Hummina Shadeeba]

The lover voltage options will probably have better efficiency

What adjustments can be made to make the motor as efficient as possible?
I read the data out of the Vesc isn’t accurate so I got a clamping amp meter and was planning to adjust some settings and just see the current draw at full speed. That’s the extent of my guesses.

 

[72V]

My bad, I forgot I already asked that question. I've been reading and watching a ton of videos trying to get an understanding on how everything works together. All the information can be overwhelming. On top of that it seems that I keeping coming across a lot of conflicting information.

 

[72V]

What adjustments can be made to make the motor as efficient as possible?
I read the data out of the Vesc isn’t accurate so I got a clamping amp meter and was planning to adjust some settings and just see the current draw at full speed. That’s the extent of my guesses.

Honestly, i have no idea what BMS comes with the batter. I ordered it from Amorge. The only information they have on the listing for the battery is that the BMS has Bluetooth. But I like the idea of adding a fuse!

 

[72V]

No video. No video and now it sits in the yard till I get my license n the cops pulled me over. It could’ve been really bad but “the system was down” and they were unable to tow and impound.
I built the battery with batteryhookup cells. It’s 4.5 watthours with ion cells and 2.5 with lifepo4

I bought the bike new and stripped it.

What cells did you use? 18650, 21700? I saw some prismatic cells on battery hookup that I considered buying originally. However, to get the voltage and Ah that I wanted the pack would have been too large. They were a great price tho. Im still considering buying some to build a battery for a go-kart where I have more space to work with. They are 3.7v cells X2 with 16ah and 200a sustained and they also sell these cell divders that just bolt together with all-thread. Looks super easy to build.

 

[j bjork]

What adjustments can be made to make the motor as efficient as possible?
I read the data out of the Vesc isn’t accurate so I got a clamping amp meter and was planning to adjust some settings and just see the current draw at full speed. That’s the extent of my guesses.

No, I meant the lower voltage controllers will probably be more efficient than the higher voltage ones, when they are both ran on the same voltage. I dont know nearly enough about vesc tuning to answer that.