Controller Throttle Problems

I need a hand with a controller throttle problem.
Sabvoton 72150, the problem is the bike slows down a little with max throttle, or when the bike is up to some speed rolling back the throttle will increase the power and speed...
Full throttle is showing 5v in the app or PC program, and changing it from 4.8v-5v in the software makes little difference.

I'm open to suggestions. Link below.


https://drive.google.com/drive/folders/1WIlWNIiIfFt9DIaXNAt6-GArQq1kYI5X?usp=sharing

You didn't say which throttle it is. Hall sensor throttles normally give out around 1.2v at no twist and 4.2v at full twist. The voltages are dependent on the magnetic field produced by a pair of magnets. With no magnetic field, you get 2.5v (half throttle). To get the 1.2v, a south facing magnet must be immediately adjacent to the hall sensor, and to get 4.2v, the north facing one has to be against it.

What can happen in plastic throttles is that the end-stop gets damaged, so the north magnet can go past the hall sensor. As it gets further away again, the voltage drops the same as if you were releasing the throttle. This problem happens mainly on full width ones, when you're holding full throttle and hit a bump. Though it can happen on any plastic throttle, thumb throttles don't get it so much because the bump goes through the grip and up your arm rather than through your thumb.

Throttles are therefore not failsafe. Many people have dropped their bikes and smashed their throttles, whereupon the motor spins up to half maximum speed because there are no magnets to pull the signal down.

It would almost have to be the throttle itself. You could test by using a voltmeter on the throttle signal line.

You could replace the throttle or if you are cheap like me, take it apart and put something in there to stop the travel at the maximum speed point.

This is what I first thought it was the throttle, but I have changed it for another cheap hall throttle and it is the same, also the voltage moves up and down when turning the throttle. Ie, closed 1.10v up to full 5v, that's why I have tried setting the max needed volts down from 5v to 4.8v in the settings but it is still the same. So you can see the voltage in the app or PC software moving like it is meant too from 1.10v to 5v...

It is hard to explain but to give it full power you need to give it full throttle like normal... but then when you get up to speed rolling back to around 90% down to 50% will increase the speed even more. So when so are trying to slow down it will speed up.
I'm thinking the throttle voltages are not staying the same when ridding like they are with the wheels off the ground?
Apart from that, I'm stumped, I'm going to try my other throttle off my own bike and see if that helps tomorrow.

Something doesn't sound right. A throttle hall sensor (SS49) supplied with 5v can only output about 4.2v on the signal wire. Did you measure your 5v supply? Is the battery in your meter run down? Maybe time for a new one.

Hardergamer said:

It is hard to explain but to give it full power you need to give it full throttle like normal... but then when you get up to speed rolling back to around 90% down to 50% will increase the speed even more.

Click to expand...

backing down from 90% to 50%, is the speed affected proportionally?

That's very strange.

One possibility is something is pulling down the 5v supply going to the throttle. Could be any number of things including the MCU in the controller, the motor halls, or a bad voltage regulator. If you had a way to measure the 5v line while running the motor you could test for this.
I sort of remember somebody else having a similar problem and they fixed it by making a separate 5v supply for the throttle.

Thanks for the feedback. And yes E-HP as you roll back from 90% down to about half or 50% throttle you gain speed and power.
I couldn't get the time to look at it yesterday, but hopefully, I can tonight and tomorrow...
If changing the throttle does not help I have to start measuring the real voltages with my Fluke.

One more thing d8evh said about a Hall throttle should not give out 5v on the signal? Well, this one is showing 5v full throttle in the app and windows 10, but both programs show battery about 0.8v to high as well, so I betting they are all off...
Maybe if I put a resistor on the signal return?