Please confirm if I understand your setup/wiring correctly.
@Amirmkr It is not clear what your PWM = 255 means. I guess you are using Adruino/Teensy4 PWM 255 on top of the AccelStep which would make the control signal a bit completed.
I usually test by hand, manually, use PWM signal from a PWM/square wave sign gen (See my chat records for more details) So I would put away the MPU Arduino/Rpi, and use 8kHz (ie, 8000 steps per second) to the step input of driver, and dc 0V/5V direction signal, ...
You question is on how to find torque constant, but our discussion so far only talks about torque, not torque constant. For a particular DC motor product, its torque constant is a constant, a fixed value, a ratio based on the architecture of the particular motor.
On the other hand, torque (not torque constant) is a variable, depending on a couple of things. In other words it is a (dependent) variable depending on other (independent) variables. The following graph shows the independence.
Discussion on question by Amirmkr: Ho…
