If i tell a moter to rotate 75% with one buttton press and -75% with another the positive will work fine but ithe negitive will be like half the speed and be verry jumpy and jittery. idk what to do is it eletric and if so how do i check?
It’s almost certainly a code issue where you set the motor multiple times.
It sounds like it is switching rapidly from -.75 to +.75.
If you can post your code, we can help fix it.