All street-legal motorcycles in Utah must display a Utah license plate to ensure the vehicle is legally registered with the state. This decal is proof of registration, verifying that the motorcycle complies with state laws and regulations for road use. Displaying a registration decal is a common requirement as it is necessary for identification purposes and to confirm that the motorcycle is up-to-date with registration fees and inspections. This requirement helps in the enforcement of vehicle regulations and in maintaining road safety and legal compliance throughout Utah.