When i have my finger on"S" (because it seems pushing it once or twice in a row wont keep it moving backwards) and I'm slowwwly rolling backwards and pivot turn...when my finger leave "S" it lunges forward. I don't understand why tapping "S" once won't start a reverse motion and hold it, and maybe pressing it twice in a row won't send it full reverse speed.I think Shift S or something will do that but,, if you hard pivot and it comes to a stop, it'll lunge forward.