OTR Tires Worldwide
What constitutes an OTR tire?
Tires seem like very simple things, don’t they? Many people assume that a tire is just a basic round piece of rubber that is inflated by a tube. In the retail industry there are thousands of different variants of tire depending on the manufacturer and the use that it will be put to. Off-the-road tires or, OTR Tires are built to take a massive amount of weight and roll through conditions that would stop most cars dead. They all share 3 common types of construction:
Bias – A Bias tire means that it is of cross ply construction. It uses cords that stretch from bead to bead. A bead is a bunch of high tensile steel wire that ties the tire to the rim. The cords are laid in layers at opposing angles of approximately 35 degrees to form a crisscross pattern. The tread is then adhered over that pattern. The primary advantage of a tire with this construction is that it allows for the entire body of the tire to flex. This flexibility allows for a comfortable and smooth ride even on uneven or rough terrain. The down side of bias tires is that they have less traction and control at higher speeds.
Belted Bias – An OTR tire of this type starts out with similar construction to the bias. It will usually have two or more of the crisscross layers that we mentioned before but it then has corded or steel stabilizing belts that are attached underneath the tread. Those belts and crisscross layers are at differing angles similar to the Bias tire listed above. This construction really improves the tires performance when put up against non-belted bias tires. Belted Bias is an improvement on the bias because it retains the comfortable ride but the increased stiffness of the construction lessens the rolling resistance at high speeds.
Radial – A radial tire is in some ways the opposite of a bias tire and in others it is combination of Bias and Belted Bias. Radial utilizes cords that extend from the beads and across the tread but they are at right angles to the centerline of the tread. The cords are parallel to one another and stabilizer belts are put into place beneath the tread. All of those things come together to strengthen the tire and provide a long life for the tire, better control at high speeds and lower rolling resistance as well. The disadvantages are that the ride is much rougher at lower speeds and OTR tires will not see as much of a self-cleaning ability.
These categories only represent the basic construction of OTR tires. There are many more OTR tire varieties available that are designed for special environments and conditions.