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Stealth Bomber clone disappointment

AndrewZ

New here
Joined
Feb 10, 2026
Messages
23
Location
EU
Hello everyone.

I am by all means a noob.

I have wanted a stealth bomber bike ever since I saw one online and I bought one from a company from Alibaba that supposedly had stock in Europe (Poland).

They promised me a 72v40ah 12000w bike with a QS273 and a Sabvoton 180a controller.
The bike can slowly get to 40km/h and it will keep accelerating slowly to 60 and even more if I keep at it but the real problem is it is gutless down low and cannot climb a minor hill. I will attach pictures of the motor controller and battery.
I am sure the controller is NOT a sabvoton and the motor itself does not look like a QS.
I don't know if the seller will take it back but I have opened a claim and I want to look at my options here. Maybe I get to keep the bike with a refund of half of its value so I can actually buy the better parts to make it faster? Or it would be better to send it all back?
I know that you get what you pay for but that wasn't actually cheap..
Any help or insight is appreciated.
 

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Hello everyone.

I am by all means a noob.

I have wanted a stealth bomber bike ever since I saw one online and I bought one from a company from Alibaba that supposedly had stock in Europe (Poland).

They promised me a 72v40ah 12000w bike with a QS273 and a Sabvoton 180a controller.
The bike can slowly get to 40km/h and it will keep accelerating slowly to 60 and even more if I keep at it but the real problem is it is gutless down low and cannot climb a minor hill. I will attach pictures of the motor controller and battery.
I am sure the controller is NOT a sabvoton and the motor itself does not look like a QS.
I don't know if the seller will take it back but I have opened a claim and I want to look at my options here. Maybe I get to keep the bike with a refund of half of its value so I can actually buy the better parts to make it faster? Or it would be better to send it all back?
I know that you get what you pay for but that wasn't actually cheap..
Any help or insight is appreciated.
I would put together the cost of the replacing the motor, controller and battery, so you can make an informed decision. This assumes you have the knowledge, skills, and tools to do the work.
 
I would put together the cost of the replacing the motor, controller and battery, so you can make an informed decision. This assumes you have the knowledge, skills, and tools to do the work.
Yeah that's why I joined this forum. I know how to do basic electrical work and soldering etc so if I have proper instructions I'm sure I'll figure it out. What scares me most is programming controllers etc. With that said what I hope to find out here is the following:
1) What parts are those in the photo? Like what did the bike come with exactly?
2) Cost and availability in EU or ship to EU for the parts I will need to make this bike what it was supposed to be.
 
Yeah that's why I joined this forum. I know how to do basic electrical work and soldering etc so if I have proper instructions I'm sure I'll figure it out. What scares me most is programming controllers etc. With that said what I hope to find out here is the following:
1) What parts are those in the photo? Like what did the bike come with exactly?
2) Cost and availability in EU or ship to EU for the parts I will need to make this bike what it was supposed to be.
Not based on those pics. Might help if you provided the original listing.
I would ask for a full refund. Not sure what identifying the existing fake components would be. Might be worth noting the battery has 35Ah, not 40Ah stamped right on it. If they won’t refund, ask for $2k back for replacing the fake stuff.

Ps. I’ve never seen a battery that come with its insurance policy stamped on the side. Not sure what to make of that. Good thing to have the pic, in case it burns up.
 
Yeah I have already asked for a full refund on my dispute with loads of evidence that the hardware provided is not what was promised by the seller nor what was in the listing. I don't have the listing handy right now but it wasn't anything particular there. Just said 12kw stealth bomber 72v40ah 180a. In my messages with the seller (to which I gave access to the dispute team so that they can see them) the seller said that I would be getting a QS273 12kw, 72v40ah and sabvoton 180a. None of these happened. So I think I make a pretty good case. We'll see.
 
Yeah I have already asked for a full refund on my dispute with loads of evidence that the hardware provided is not what was promised by the seller nor what was in the listing. I don't have the listing handy right now but it wasn't anything particular there. Just said 12kw stealth bomber 72v40ah 180a. In my messages with the seller (to which I gave access to the dispute team so that they can see them) the seller said that I would be getting a QS273 12kw, 72v40ah and sabvoton 180a. None of these happened. So I think I make a pretty good case. We'll see.
Remember if they side with the seller and you paid with a credit card, call up your credit card company and ask to file a chargeback for product not as described or counterfeit, I would say counterfeit. Idk how it works in Poland but it seems pretty standard.
 
Remember if they side with the seller and you paid with a credit card, call up your credit card company and ask to file a chargeback for product not as described or counterfeit, I would say counterfeit. Idk how it works in Poland but it seems pretty standard.
I read a lot stories online about this and while yes some people say they side with the seller there were not a few stories of people getting refunds. I paid via paypal with a revolut card so I have many safety layers. I will first wait it out with Alibaba to see what they decide before I make chargeback.
 
Ah you are having a typical new ebike buyer's experience:
Buy a cheap completed bike and find out shortly after that it's crap.

Programming a controller is not too difficult once you understand the basics. People here can help you figure it out.
Here is an intro to controllers article i'm working on:
Knowledgebase
 
Ah you are having a typical new ebike buyer's experience:
Buy a cheap completed bike and find out shortly after that it's crap.

Programming a controller is not too difficult once you understand the basics. People here can help you figure it out.
Here is an intro to controllers article i'm working on:
Knowledgebase
Thanks for the input. I'm new when it comes to e-bikes yes. I had 2 powerful e-scooters bought from Banggood but never Alibaba. I started reading about phase amps. It seems this one is set up with a 80 phase amp current rate limit. I could raise it from the display but I really don't know what the BMS and battery can actually hold or if even the controller can output more than 80. Until the fate of this bike is decided I can't damage it in any way.
 
80A phase is quite low for a supposedly bigger motor.
Do you have a realtime voltage readout of the battery, or just some bars?

We could take a pretty good guess at how much the battery can tolerate.
I don't want to see more than 4 volts sag on a 72v pack because this is where we gotta start worrying about thermal limits.
If you see 2 volts then you are golden to start upping the power.
 
80A phase is quite low for a supposedly bigger motor.
Do you have a realtime voltage readout of the battery, or just some bars?

We could take a pretty good guess at how much the battery can tolerate.
I don't want to see more than 4 volts sag on a 72v pack because this is where we gotta start worrying about thermal limits.
If you see 2 volts then you are golden to start upping the power.
It has the UKS6 display and I think there is an option to see voltage instead of battery percentage. I can test it tomorrow. Does it have to be fully charged?
 
It has the UKS6 display and I think there is an option to see voltage instead of battery percentage. I can test it tomorrow. Does it have to be fully charged?
I actually tested it now. Please tell me if my test counts. I climbed on the bike in the garage and put the wheel against the wall and floored the gas. Voltage was at 80-81v and dropped to 78-79v no matter how long I held it. Then I went into the display menu and tried raising the amps from 80 to 100 and tried the same test, same results.
 
I actually tested it now. Please tell me if my test counts. I climbed on the bike in the garage and put the wheel against the wall and floored the gas. Voltage was at 80-81v and dropped to 78-79v no matter how long I held it. Then I went into the display menu and tried raising the amps from 80 to 100 and tried the same test, same results.
That's pretty nuts. Hopefully the motor didn't sustain permanent damage. Do you have a temp sensor in the motor?
 
That's pretty nuts. Hopefully the motor didn't sustain permanent damage. Do you have a temp sensor in the motor?
I didn't hold it for more than a second or two each time. Maybe I'm an idiot but no damage at all thankfully. This bike has a lot of shortcomings to even have a temp sensor. So probably not. I'll take it out and test it tomorrow with some real RPMs.
 
Nice test!

I'm thinking you can get away with 120a.
I would try it and periodically put your hands on the motor after heavy loads.
If you cannot keep your bare hands on it for more than 5 seconds it is too hot.

The same test applies to controllers.

I would keep an eye on battery temps if possible using the same technique. But the metric is different. 'i can barely detect any warmth' is where you want to be. 'it's kind of warm' is where you want to stop. Why? we have to think about the cells in the center of the pack. If outside is notably warm, inside is 2-3x hotter.

To do good measurements requires a laser thermometer or cheap FLIR. But if you follow the caveman-level procedures above, you should be safe.

We don't know why this setup was so derated and you are about to find out which part is the weakest link as you tune the power upwards.
If you are lucky then they detuned it for risk aversion reasons.

I've tuned many a bike this way :)
 
Nice test!

I'm thinking you can get away with 120a.
I would try it and periodically put your hands on the motor after heavy loads.
If you cannot keep your bare hands on it for more than 5 seconds it is too hot.

The same test applies to controllers.

I would keep an eye on battery temps if possible using the same technique. But the metric is different. 'i can barely detect any warmth' is where you want to be. 'it's kind of warm' is where you want to stop. Why? we have to think about the cells in the center of the pack. If outside is notably warm, inside is 2-3x hotter.

To do good measurements requires a laser thermometer or cheap FLIR. But if you follow the caveman-level procedures above, you should be safe.

We don't know why this setup was so derated and you are about to find out which part is the weakest link as you tune the power upwards.

I've tuned many a bike this way :)
Thanks! So I'm thinking take the side panels off tomorrow morning, get it out and test at 100a if there is any heat in the motor battery or controller, if not raise to 120a and check for heat again? Could it be that no matter what I set the amps to from the display, the controller itself is limited to say 80a and won't give out any more?
 
I didn't hold it for more than a second or two each time. Maybe I'm an idiot but no damage at all thankfully. This bike has a lot of shortcomings to even have a temp sensor. So probably not. I'll take it out and test it tomorrow with some real RPMs.
My harbor freight heat gun puts out 1500W. Stalling your motor mean 12kW is being converted directly to heat, since there is no mechanical movement. That's 8 heat guns worth of heat. That will never make it to the case cover in a couple of seconds, and without statorade, there's no path for the heat; it's all being applied to the stator. I'd let it cool 20 minutes between tests, and never hold more than 1 second. If you have a temp sensor, you'll see how quickly the stator temp rises when stalled, or even when spinning very slowly.
 
Nice test!

I'm thinking you can get away with 120a.
I would try it and periodically put your hands on the motor after heavy loads.
If you cannot keep your bare hands on it for more than 5 seconds it is too hot.

The same test applies to controllers.

I would keep an eye on battery temps if possible using the same technique. But the metric is different. 'i can barely detect any warmth' is where you want to be. 'it's kind of warm' is where you want to stop. Why? we have to think about the cells in the center of the pack. If outside is notably warm, inside is 2-3x hotter.

To do good measurements requires a laser thermometer or cheap FLIR. But if you follow the caveman-level procedures above, you should be safe.

We don't know why this setup was so derated and you are about to find out which part is the weakest link as you tune the power upwards.
If you are lucky then they detuned it for risk aversion reasons.

I've tuned many a bike this way :)
So I tried the test at 80a and then 100a. Same behavior. Voltage started around 81-82 and dropped to 79-78 max when driven at 20km/h speeds. The problem is at 100a I didn't notice any improvement. It's still as slow as it was at 80a.
 
Please ask the question in the forum. It's the only way others can learn from the answer.
My availability is extremely sporadic
 
I figured I'd message you directly since you've been the most eager person to help with this.
Anyway, I tried raising the phase amps from the UKS6 display. First 80 then 100, then even 120. I did not notice any serious improvement that could pass as anything more than a "tailwind". With all those tests the battery voltage went from like 81-82 to 79-78. One time it went to 77 but climbed back to 78 without me letting go of the throttle.
Also, I put the bike on a stand and with the rear wheel in the air the speedo wrote 115km/h with the voltage again not dropping lower than 78.
I don't know if that tells us anything but as soon as I ride it (200lbs) it is totally gutless. I then tried to remove the battery and controller to have a better look at them. Unfortunately I can't open the battery (at least not until the dispute with ali is done) because the top part has rivnuts on and I would have to drill them out. It doesn't say any BMS info on the label. The controller on the other hand looks like trash. Only marking I could get from it was "JX-1". No other stickers, nothing.
I also uploaded a photo of the charger that came with it, maybe could tell you something about the battery's amp capability?

I also thought I'd give some more info on how the motor behaves. From a stop at full throttle it feels like it's giving a few singular pushes or pulses until it all syncs up as rpms rise. Also while riding I thought that around 30km/h something vibrates and goes away unless I keep that speed steady. After a good 10 minute ride testing Phase amps at 80 and 100 I returned home and the motor was warm but I could keep my hand on it for more than 5 seconds, battery and controller the same.
 

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I figured I'd message you directly since you've been the most eager person to help with this.
Anyway, I tried raising the phase amps from the UKS6 display. First 80 then 100, then even 120. I did not notice any serious improvement that could pass as anything more than a "tailwind". With all those tests the battery voltage went from like 81-82 to 79-78. One time it went to 77 but climbed back to 78 without me letting go of the throttle.
That seems very low if your controller is rated at 180A (line current). 360A to 500A seems more inline with that size controller. 120A phase would be something a good 40A controller could output, so you're starving your motor. As neptronix asked earlier, what are your battery amps set to?
The motor's windings may also be a factor, since your original description of taking forever to get to top speed (but still achieving it), sounds like a faster winding (so it's trading off acceleration for speed).
 
That seems very low if your controller is rated at 180A (line current). 360A to 500A seems more inline with that size controller. 120A phase would be something a good 40A controller could output, so you're starving your motor. As neptronix asked earlier, what are your battery amps set to?
The motor's windings may also be a factor, since your original description of taking forever to get to top speed (but still achieving it), sounds like a faster winding (so it's trading off acceleration for speed).
If you read again and look at the photos I posted earlier there is NO way this controller that came with the bike is anywhere close to 180 (like it was described in the listing). All of the hardware is a joke compared to what was described in the listing. Like I said I can't open the battery to look at the BMS specs until the dispute with ali is finished. The controller looks like a generic china crap, the motor is big physically and wide but has no markings so definitely not a QS, the battery only says 72v 35ah on it and nothing more.
 
If you read again and look at the photos I posted earlier there is NO way this controller that came with the bike is anywhere close to 180 (like it was described in the listing). All of the hardware is a joke compared to what was described in the listing. Like I said I can't open th battery to look at the BMS specs until the dispute with ali is finished. The controller looks like a generic china crap, the motor is big physically and wide but has no markings so definitely not a QS, the battery only says 72v 35ah on it and nothing more.
I believe just by the size that it's bigger than a 40A controller, so the question still stands, what is your battery current limit set to in your controller parameters?

PS, I'm using a cheap as crap dumb $70 "80A" controller, but it still provides 7kW off the line at 72V.
 
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