Which motor vehicle operator is prohibited from changing gears while crossing the tracks at an uncontrolled railroad grade crossing?

The prohibition on changing gears while crossing tracks at an uncontrolled railroad grade crossing is specifically relevant to motor buses due to their size, weight, and the potential for significant passenger safety risks. Motor buses are typically larger vehicles that may require more time to accelerate and decelerate. Changing gears while traversing these crossings can lead to vehicle instability or stalling, which can be particularly dangerous in situations where quick reactions are necessary due to approaching trains.

In contrast, smaller vehicles like bicycles, pickup trucks, and motorcycles can usually change gears more easily without the same level of risk. These vehicles have different dynamics and engine responses that allow for more agile handling at crossings. The rules are designed to ensure the safety of both the operator and passengers, reflecting the unique characteristics and challenges that come with driving a motor bus in environments where rail crossings are present.