Solid Rubber Tires
After the discovery of vulcanization tires were made out of solid rubber. These tires were strong, absorbed shocks and resisted cuts and abrasions. Although they were a vast improvement, these tires were very heavy and did not provide a smooth ride.
Today there are still types of tires made of solid rubber
The pneumatic rubber tire uses rubber and enclosed air to reduce vibration and improve traction. Robert W. Thomson, a Scottish engineer, first patented the air filled tire. Unfortunately the idea was too early for its time and was not a commercial success.
In 1888 John Boyd Dunlop of Belfast, Ireland became the second inventor of the pneumatic tire. Dunlop claimed to have no knowledge of Thomsons earlier invention.
The second time around the pneumatic tire caught the publics attention. The timing was perfect because bicycles were becoming extremely popular and the lighter tire provided a much better ride.
Bias Ply Tires
For the next fifty years vehicle tires were made up of an inner tube that contained compressed air and an outer casing. This casing protected the inner tube and provided the tire with traction.
Layers called plys reinforced the casing. The plys were made of rubberized fabric cords that were embedded in the rubber. These tires were known as bias-ply tires. They were named bias ply because the cords in a single ply run diagonally from the beads on one inner rim to the beads on the other. However, the orientation of the cords is reversed from ply to ply so that the cords crisscross each other.
Today you can still find bias-ply tires as authentic equipment for antique and collector cars, as well as for certain type of off-the-road tractor tires.
The first introduced steel-belted radial tires appeared in Europe in 1948. Radial tires are so named because the ply cords radiate at a 90 degree angle from the wheel rim, and the casing is strengthened by a belt of steel fabric that runs around the circumference of the tire.
Radial tire ply cords are made of nylon, rayon, or polyester. The advantages of radial tires include longer tread life, better steering and less rolling resistance, which increases gas mileage. On the other hand, radials have a harder riding quality, and are about twice as expensive to make.
The beauty of the radial design is that it separates the functions of the sidewall and crown of the tyre, allowing greater vertical flexibility whilst ensuring that there is still as much surface in contact with the road as possible. In classic radial tyres the sidewall has a one or two layers of textile cord giving good flexibility, and the tread is made rigid by combining the casing layer with two (or more) layers of steel cord bracing plies. Both these factors give the classic radial tyre excellent road holding capabilities and a longer life span when compared to vintage cross-ply tyres.
Performance tires tend to be designed for use at higher speeds. They often have a softer rubber compound for improved traction, especially on high speed cornering. The trade off of this softer rubber is a lower treadwear rating.
Performance tires are often called summer tires, because they sacrifice wet weather handling, by having shallower water channels, and tire life from softer rubber compounds, for dry weather performance. The ultimate variant of performance tires has no tread pattern at all and is called slick tire. Slick tires are not legal for use on public roads in most countries due to their extremely poor wet weather characteristics.
Winter tires are designed to provide improved performance under winter conditions compared to tires made for use in summer. The rubber compound used in the tread of the tire is usually softer than that used in tires for summer conditions, so providing better grip on ice and snow. Winter tires often have fine grooves and siping in the tread patterns that are designed to grip any unevenness on ice. Winter tires are usually removed for storage in the spring, because the rubber compound becomes too soft in warm weather resulting in a reduced tire life.
Dedicated winter tires will bear the "Mountain/Snowflake Pictograph" if designated as a winter/snow tire by the American Society for Testing & Materials. Winter tires will typically also carry the "M&S" (Mud and Snow) designation.
Many winter tires are designed to be studded for additional traction on icy roads. The studs also roughen the ice, so providing better friction between the ice and the soft rubber in winter tires. Use of studs is regulated in most countries, and even prohibited in some countries due to the increased road wear caused by studs.
These are an attempt to make a tire that will be a compromise between a tire developed for use on dry and wet roads during summer, and a tire developed for use under winter conditions, when there is snow and ice on the road. However, the type of rubber and the tread pattern best suited for use under summer conditions cannot, for technical reasons, give good performance on snow and ice. The all-season tire is therefore a poor compromise, and is neither a good summer tire, nor a good winter tire.
All-Season tires are marked M+S, i.e. the same as winter tires. However, due to the compromise with performance during summer, winter performance is usually not comparable with a winter tire.
All-terrain tires are typically used on SUVs and light trucks. These tires often have stiffer sidewalls for greater resistance against puncture when traveling off-road, the tread pattern offers wider spacing than all-season tires to evacuate mud from the tread.
Within the all-terrain category, many of the tires available are designed primarily for on-road use, particularly all-terrain tires that are originally sold with the vehicle.
Mud terrain tires are characterized by large, chunky tread patterns designed to bite into muddy surfaces and provide grip. The large open design also allows mud to clear more quickly from between the lugs.
Mud terrain tires also tend to be wider than other tires, to spread the weight of the vehicle over a greater contact patch to prevent the vehicle from sinking too deep into the mud.
Depending on the composition and tread pattern, many mud terrain tires are not well suited to on-road use. They can be noisy at highway speeds, and due to the open tread design, they have less of a contact area with the road, limiting traction. The large lugs on mud tires tend to tear and chip on roads, because they are made from hard rubber compounds that do not bend easily.
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