Sondors MSX throttle "sticking" power trickling.

[farmbike]

Hello
I have a Sondors MSX with the 48V 750 Bufang hub motor. Over 5000 miles.

Bike goes along nicely but an issue arose. When you release throttle a little power still goes to the motor. Bike wants to still move forward but planting your feet can hold it back. Apply brakes and motor powers off. Release brakes and bike wants to roll ahead again.

Buddy, who has more experience than myself, said to switch out throttle. We swapped out 2 different thumb throttles with a similar 3 pin connector. These throttles could not even get the motor to respond . These throttles were obviously not compatible with Sondors.

We are both stumped now.....is it motor, controller, sensors or do we need to find a Sondors compatible new throttle?

Where do you find an original Sondors 3 pin throttle?

Cheers Thx .

 

[Chalo]

Whatever the problem is, you can probably fix it by using a potentiometer throttle instead of a Hall effect throttle.

Hall throttles take a 5V input and return something in a range from a little under 1V to a little over 4V. Potentiometer throttles take the same 5V input and return a signal between 0V and 5V.

 

[99t4]

Does this ebike have PAS in addition to the throttle?

 

[afzal]

If throttle signal & ground is accessible, connecting a pull down resistor (say 10K) between them perhaps will help

 

[E-HP]

Buddy, who has more experience than myself, said to switch out throttle. We swapped out 2 different thumb throttles with a similar 3 pin connector. These throttles could not even get the motor to respond . These throttles were obviously not compatible with Sondors.

There are no wiring standards for Chinese parts. The throttle may have 3 conductors, but you’d be lucky if you just bought any old throttle that matches the stock one, so you may need to swap the conductors around. Can you post a pic of the controller’s throttle connector, and the new throttle connector?

 

[fechter]

Right. You should be able to make a generic throttle work, but the wire colors most likely won't match and you'd have to figure out what each of the wires does. There's a 5v supply, Ground, and the throttle signal.

You could possibly "fix" the existing throttle by putting a resistor from the signal line to ground. My guess would be around 10k ohms. Use the highest value that corrects the problem.

There may also be a way to fix the throttle by adjusting the position of the magnet or sensor inside. Some throttles come apart easy, some don't.