We ride on the side of the road all time, that's how we get anywhere, busy highways too. She has no issues with semis, harleys or trucks blowing past us. I think the train hit his brakes or something because it made a aweful noise, worse than I'm used to hearing.
I could never get closer than I was as my dad has told me more horror stories than I ever needed to know. He smooshed too many things, animals, people, cars, that I am just terrified of trains up close. Too many things can come flying off and the smallest rock can cause a derailment. So trust me I will always try to leave an out for us.
My biggest concern is when the tracks are by a busy highway. She quite often turns off that self preservation button.