Crossbuck signs indicate: Do you currently have motorcycle insurance? Insurance is mandatory to drive in Montana Yes I have insurance. But please show me your best quotes. No, please help me find the best insurance. Question Crossbuck signs indicate: Answers Railroad crossings. School zones. No passing zones. Hospitals. Explanation A crossbuck sign tells road users to yield to any trains at an upcoming railroad crossing. Riders should never try to race a train.