I use 28 speed steps, with a top speed scale of 56 MPH. I set up each locomotive, so speed step one is 1 scale MPH, speed step 2 is 2 scale MPH, I do this up to speed step 10. Speed steps 11 through 19, increase by 2 scale MPH, and speed steps 20 through 28, increase by 3 scale MPH. This way...