What size tire goes on 18 inch dirt bike rim?

For an 18-inch dirt bike rim, the appropriate tire size typically falls within the range of 100/100-18 to 110/90-18, depending on the bike's specifications and intended use. It's important to consult the owner's manual or the manufacturer's recommendations for the specific model to ensure proper fit and performance. Additionally, factors like terrain and riding style may influence the choice of tire size.