No, you do not as the computer does it, provided you install the correct one.
check for a faulty speed buffer module
You would fix it by replacing the instrument cluster. The speedometer itself may not be faulty, it is more likely to be a problem with the speed sensor.
check the fuse panel
you replaced speedo, so try replacing speed sensor
To accurately calibrate the speedometer on your road bike for optimal performance, you can use a GPS device to measure your speed and compare it to the reading on your speedometer. Adjust the settings on your speedometer accordingly to ensure accurate readings.
Speed sensor
There is no speedometer cable. MPH is calibrated using a speed sensor. If your speedometer is not working, you have a bad speed sensor module.
The speed sensor is located in the speedometer assembly, at the back of where the speedometer needle connects.
To accurately calibrate the speedometer on your bike, you can use a GPS device to measure your speed and compare it to the readings on the speedometer. Adjust the settings on the speedometer accordingly to ensure precise readings during your rides.
The vehicle speed sensor which is an integral part of the speedometer
controls speedometer
the speed sensor, trans. sensor , or the speedometer cable