A tyre is the rubber covering around a wheel's rim that resembles a ring in shape. The main functions of a tyre are to protect the wheel's rim, enhance the vehicle's performance, and create a smoother ride. It does these things by providing traction between the surface of the road and the vehicle and cushioning and absorbing the impact and shock from the wheels travelling over the road. Beyond the rubber that most people think of when they think of tyres, they are made of several other materials. Some common materials include natural and synthetic rubber, carbon black, fabric, wire, and other chemical compounds. Broadly speaking, tyres consist of tread and a body. The tread provides traction while the body provides containment for the compressed air that serves as cushioning.
General knowledge of the types of tyres and their components is necessary to choosing a set of good, reliable tyres for a vehicle. Tyres are available at numerous tyre stores, as well as at some auto parts stores and discount stores. eBay, along with other online retailers, also features a large collection of tyres in a number of sizes and brands.
Components of a Tyre
A tyre is made up of several parts and different materials that are used in varying proportions according to the specifications of different manufacturers. The basic know-how of these components helps a buyer in purchasing the right tyre.
Tread is the part of a tyre that comes in contact with the road surface and features a pattern on the rubber surface of the tyre. 'Contact patch' is a term that is often used for the portion of the tyre that is in contact with the road at any particular instance. The tread is a thick rubber that provides traction that resists wear for long periods of time. The pattern is characterised by the shape of lugs, voids, grooves, and sipes.
Specific parts of tread design that come in contact with the road surface
Spaces between lugs are known as voids
Allow lugs to bend and evacuate water
Channel the water away and run across the circumference of the tyre
Valleys cut perpendicular to grooves and across the tyre
Prevent hydroplaning by allowing the water to escape sideways
In order to minimise the noise level, tread patterns feature asymmetrical lug sizes. Keeping the void ratios low enhances the performance of tyres as it provides more rubber in contact with the road and increases traction. Mud and snow (M&S) tyres have comparatively higher void ratios. They provide enhanced gripping performance and channel away mud and rain. Specialised or custom tyres generally perform better than all purpose/all weather tyres in specified conditions.
Tread lugs come in contact with the road surface and provide traction. They are compressed as they enter the road contact area. On rotation, tread lugs deform for some moments and restore to their original form on leaving the road contact area. The tyre exerts variable forces on the vehicle during the recovery and deforming cycle.
Tread voids provide the lugs the opportunity to bend and deform while entering or leaving the contact area. They also provide channels for mud, snow, and rainwater to be channelled away from the contact area. Void ratio is defined as the void area divided by the total tread area. Void areas that are low have comparatively high contact area and high traction on dry, clean pavement.
Rain groove is a design element of the tread pattern that has the specific purpose of guiding the water or mud away from the contact area. In some cases, rain grooves are circular, and in other high performance tyres, they are angled from the centre towards the sides of the tyres. Some tread patterns are designed to throw the water out from beneath the tyre so that the tread flexing action results in a smooth ride in differing weather conditions.
Sipes are valleys that are cut perpendicular to rain grooves across the entire tyre. They prevent hydroplaning by allowing the water to escape sideways. Sipes improve the flexibility of the lugs to compress and deform and cause a reduction in the shear stress and heat build up. For greater traction, many enthusiasts have been siping their off-road tyres. Many manufacturers are now offering manufactured siped off-road tyres.
Also known as wear indicators, wear bars are an indicator of whether a tyre has reached its wear limit or not. Mostly they are located at the base of tread grooves and are raised features. When wear bars connect across the lugs, it is time to change the tyre.
The component of a tyre that joins at the rim on the wheel is known as the bead. Generally, it is reinforced with steel wire and compounded of rubber that is of low flexibility and high strength. Beads ensure that the air does not leak from a tubeless tyre by seating firmly against the two rims on the wheel. The rim should support a tyre's profile and it's width for proper handling of a vehicle.
The sidewall bridges the tread and bead. A sidewall is largely rubber and is often reinforced with steel cords or fabric for increased flexibility and strength. Whitewalls are decorative elements that are moulded into some sidewalls.
Inextensible cords embedded in the rubber in the form of layers are known as plies. They are put in place to maintain the shape of the rubber and prevent it from stretching as a consequence of the inside pressure and heat. The orientation of plies plays a significant role in the overall performance of a tyre. It is also a recognised way of classifying tyres.
Types of Tyres
There are several ways in which tyres can be classified, and there can be several types of tyres in each of those categories. A popular way to classify tyres is by the user experience or user preferences. Several considerations using this method include the way a user drives the car, where a user lives, and the ride of the car.
Performance or Summer Tyres
As the name suggests, performance tyres are designed for buyers who intend to use their vehicles for fast, hard drives. Performance and grip, rather than longevity, are the main preferences for such tyres and a softer rubber compound is used in their making. Gripping in most cases is given preference over pumping the water out of the way on performance tyres. Warm climate and little to no rain are ideal conditions for their use. Slicks, which are extreme performance tyres, have no tread at all and are often used in motor racing.
All-season tyres are the ones mostly found on average vehicles that come out of the production units of a factory. They give equal importance to longevity, performance, grip, noise, and safety in wet weather. A harder rubber compound is often used to increase the lifespan of the tyre, but this compromises performance and grip to an extent.
Often used on trucks and SUVs, all-terrain tyres are large in size with comparatively bigger tread block patterns (noisy on normal roads) and stiffer sidewalls. The rubber compound used in these tyres is neither too soft nor too hard.
Mud tyres are at the far end of the all-terrain tyre classification. They have gigantic tread blocks that are super chunky. The only place mud tyres should be used is on loose mud and dirt. The treads look like paddles built into the tyre.
How to Buy Tyres on eBay
Tyres of various types can be purchased on eBay by using the search bar on the eBay homepage, an easy way to start the hunt. You can enter relevant queries in the search bar to see the results. For some queries, eBay proposes a few related searches, as well, that are often helpful in getting down to the right product. You can always shortlist the results based on your own preferences by selecting various filters. Possible queries for tyres might include 'tyre', 'all weather tyres', 'performance tyres', et cetera.
A recommended practice is to go through the user reviews and seller history on eBay before making a purchasing decision in order to have a better feel for the seller. Another common practice is to look for products in your vicinity first. This saves you money on the delivery charges if you are lucky enough to find the desired product locally. To do this, you need to enter your postcode as a filter in the search results. You can then pick up your tyres at an agreed upon time once the sale is complete.
A tyre fits around a wheel's rim on a vehicle with the primary functions of taking care of the wheel's rim and enhancing the overall performance and comfort of the vehicle. It also provides traction between the road surface and the vehicle and acts as a shock absorbing cushion. Tyres are made of different materials that are used in variable proportions. Manufacturers play with design properties to develop different tyres suited to different types of driving, and buyers purchase them according to their preferences. Popular materials used for manufacturing tyres include carbon black, natural and synthetic rubber, wire, fabric, and other chemical compounds. The major components of tyres include treads, lugs, grooves, voids, sipes, wear bars, plies, beads, and sidewalls. Some popular types of tyres include summer tyres, all-season tyres, all-terrain tyres, and mud tyres.
General knowledge of the various types and components of tyres is very helpful when the time comes to buy a new set of tyres. They can be purchased from specialty tyre stores and some automotive and discount stores as well as online. eBay features a very large collection of tyres in a number of styles and price ranges for various needs.