The Disadvantages of Dirt Bikes & Off-Road Tread on Roads

Dirt bikes are great fun on-road if you make them road-legal. Kits are available to help with this, but many people buy an already road-legal dirt bike or trail bike. Whichever you choose, tires are always an issue, as no tire is perfect for both off-road and on-road use. You might imagine you will change your tires every time you want to swap from one terrain to the other but in reality this is impractical.

  1. Legality

    • Some off-road tires, known as "knobbies," are not legal to use on-road. Check your state regulations and look at the details on the tire's sidewall. It may say whether or not it can be used on-road. Otherwise a DOT code may identify the tire as road-legal. These tires are known as "DOT knobbies."

    Traction

    • Knobby tires are ideal for off-road use as the knobbiness of the tire causes it to dig into dirt, grass, mud and gravelly surfaces, causing more traction. However, it is this feature that makes them less effective on-road. If you opt for very knobby tires, remember that your traction on tarmac is not going to be good, especially if the road is wet. This is because so little rubber will be in contact with the smooth, hard road surface.

    Wear

    • As knobby tires have so little rubber in contact with the road, what there is wears away faster than on other tires. Consequently they will be quite expensive to use as they will need replacing frequently.

    Compromise

    • Town and Country tires are somewhere in between slicks and knobbies and can perform adequately both on-road and off. However, "adequate" performance is about as good as it gets. There's more traction on-road as the shorter knobby bits with wider ends allow more rubber to meet the tarmac. This, of course, means the tires dig in less well on off-road surfaces. In some states you may have no option but to use Town and Country tires, however, if all full-on knobbies are banned.

    Safety

    • Safety-conscious bikers sometimes fit their dirt bike with slicks for the road. Slick tires with virtually no tread are perfect for on-road use as the more rubber surface, the better, to stick to the flat tarmac. However, slicks are useless off-road. You will slide all over the place, especially on grass and mud. Using this option would mean you have to change to knobbies every time you take the bike off-road.

    Conversion Issues

    • To make a dirt bike road-legal it has to conform to state regulations. The conversion usually involves adding lighting and mirrors and ensuring that its lights, tires and fuel tanks are approved by the U.S. Department of Transportation. Laws differ from state to state, but conversion kits simplify the process a little. Serious off-roaders usually keep a bike specifically for that purpose. Consequently road-conversions aren't done very often. Less frequent off-road riders tend to opt for a dual-purpose machine instead.