Just tested my Raspberry Pi robot car with the motors.
I run through the following sequence
Fast left (left motor reverse, right motor forward)
Fast right (opposite of above)
Slow right (left motor stop, right motor forward)
Slow left (opposite if above)
At the moment the command are sent via an input() statement, i.e. I have to press return after each command.
I’m going to see if I can get a web page to control it which would be self hosted by the Pi. That way it could be controlled by any wifi connected device with a web browser.