Knobby Tires are mainly used on off-road vehicles. They are the most common tire on Motocross bikes, and ATVs. Their versatility is one of the main reasons for their popularity. Small rubber “Knobs” on the surface potion of the tire that comes in contact with the ground provide substantially more traction than street tires. Similarly to Sports Cleats, the weight of the bike and rider causes them to dig into the surface. Knobby tires are generally not suitable for long distances on roads or paved surfaces, because they wear down the knobs and ruin the tires for off road use.