70% throttle deadband

Hi guys
Just got a junked 36v brushless scooter working by replacing a hall sensor in the hub motor. Appears to be working fine, although There’s like 70+ % dead band, and then the throttle kicks in with very little gradation. The effect is almost as bad as an on off switch, jolty . Any idea how to fix this? Also, would the controllers self learning wire be useful here?

The first thing I would do is check all the connectors to make sure that they are all properly connected. No connectors backed away from the pins etc. If that is not it, then I would check the throttle for consistency. If the throttle is not working right, it might have a bad hall sensor. After that I would make sure your e-break levers are not engaging due to poorly adjusted break tension.

Let us know.

I got a hunch it’s something to do with the hall sensors in the throttle. It looks like it’s been dropped a couple times, and the throttle mechanism got a good knock. I’m hoping I’m lucky and they just misaligned a bit.
I want to rule out the controller, hub motor, etc. poorly or misconnected parts in here would not create this kind of a consistent effect, would it?

Try checking the voltage that the throttle currently puts out. Most controllers read a range from 1.2v to 4v. The voltage should increase as you twist the throttle further down, and it should be atleast somewhat linear. If it doesn't do this, then you know its the throttle and you probably would want to replace it. If it's fine, then it's probably the motor controller.

Testing the throttle could help you discern if the throttle is faulty. Be careful not to over volt it. When I test my throttles I generely use a depleted 9v battery that is under 6v. If you can find one that is 5v even better. Connect the positive to the red wire. The negative to the black (or dark wire...maybe it is dark blue.) With your multi meter pin the ground wire and the return wire and twist the throttle to see if it has a sticking point.

Or, you can test it when it is hooked up to your controller if you do it this way.

https://www.ebikes.ca/documents/ThrottleTesting.pdf

Red and blue wires show 40v. White is about 3.55v, green at 4.2.
Got the cover off. Everything looks good. Tried cajoling the hall/magnet etc in various combos - no difference of any kind. Doesn’t kick in until past half the magnet sweep.
all other led screen functions, menues etc etc appear to work well.
What scenario would I use the selflearning in on the controller?

Jonny333 said:

Red and blue wires show 40v. White is about 3.55v, green at 4.2.
Got the cover off. Everything looks good. Tried cajoling the hall/magnet etc in various combos - no difference of any kind. Doesn’t kick in until past half the magnet sweep.
all other led screen functions, menues etc etc appear to work well.
What scenario would I use the selflearning in on the controller?

Click to expand...

The self learning controller is for your phase wires not the throttle. If your phase wires are out of sequence or you don't know the sequence, use the self learn.

Also, that throttle wiring sounds weird to me. If your red and blue are showing 40v, that would be the charge on your battery pack. Normally the red is the positive voltage from the controller. Usually 5v. The green at 4.2 might be the controller voltage, but it still sounds strange to me. If the white is 3.55, then that is the return voltage and it should be about 1v (perhaps a bit under 1v) when the motor is powered up but the throttle is not being used (The wheel not spinning) and around 4.6v to 4.8v at full throttle.

I believe that your wiring should be like this: Red = 5v+ Blue = Ground, White = Voltage return, Green = Battery voltage.

Post some pictures of what you have been doing. It might help us out. Make sure the pictures are in good focus and the file size is under 512k so you can post it. (640 x 480 aka VGA works will)

This is what controllers do when they cannot handle the eRPM of the motor. They act as an on/off switch.
The effect gets worse, the higher the voltage goes.

If this controller came off a bike with a hub motor, it would be surprising that the motor would even run at all.

My old MAC motor ( 16 poles x 5:1 reduction ) used to perform like garbage on most controllers until i found a controller that can handle how fast it was spinning.

Thanks guys. I tried testing the values again, and they don’t seem to vary much at all. I’m a little worried of doing too much poking around with my rudimentary equipment and conditions – I don’t want to short-circuit something again.
I replaced a hall sensor in the hub motor, not sure if that would contribute to the anomaly?

“This is what controllers do when they cannot handle the eRPM of the motor. They act as an on/off switch.
The effect gets worse, the higher the voltage goes.”
Sorry, I’m not familiar with eRpm, etc. Could you elaborate? It sounds like the answer would be to replace the controller? Or would a new controller quickly burn out in a similar fashion? If this is the problem, the power output is the same, it’s just the throttle gradation that is affected?
This link is exactly the same throttle, although I’m not sure if the controller is compatible. For example, A customer feedback photo shows it has low brake, whereas mine is labeled ”brakes:high level”. I tried tracking down the original serial number, but the company website doesn’t appear to be selling exactly the same controller anymore.
Ebike Brushless Controller Electric Bicycle 24V 36V 48V 250W/350W Brushless Controller With LCD Display with Shift Switch
https://s.click.aliexpress.com/e/3VWNtFS

Edit: Tried posting pictures, but they get rejected. Sorry, no idea how to make them 512 K or whatever.