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Inspection and maintenance of tires is about inspecting for wear and damage on tires so that adjustments or measures can be made to take better care of the tires so that they last longer, or to detect or predict if repairs or replacement of the tires becomes necessary. Tire maintenance for motor vehicles is based on several factors. The chief reason for tire replacement is friction from moving contact with road surfaces, causing the tread on the outer perimeter of tires to eventually wear away. When the tread depth becomes too shallow, like for example below 3.2 mm (4/32 in), the tire is worn out and should be replaced. The same rims can usually be used throughout the lifetime of the car. Other problems encountered in tire maintenance include:
Sometimes a pneumatic tire gets a hole or a leak through which the air inside leaks out resulting in a flat tire, a condition which must be fixed before the car can be driven safely.
Vehicles typically carry a spare tire, already mounted on a wheel rim, to be used in the event of a flat tire or blowout. Spare tires (sometimes called "doughnuts") for modern cars are smaller than regular tires (to save trunk space, weight and cost) and should not be used to drive very far before replacement with a full-size tire. A few vehicle models use conventional size spare tires. Jacks and lug wrenches for emergency replacement of a flat tire with a spare are included with a new car. Not included, but available separately, are hand or foot pumps (like a bicycle pump) for filling a tire with air by the vehicle owner. Cans of pressurized air can sometimes be bought separately for convenient emergency refill of a tire.
Some cars and trucks are equipped with run flat tires that may be driven with a puncture over a distance of 80 km to 100 km. This eliminates the need for an immediate stop and tire change or calling for roadside assistance.
On dry surfaces, tires have more traction when they are bald, because there is more surface area making contact with the road. The reason regular tires have treads is to avoid hydroplaning when the surface of the road is wet. Therefore racing cars competing in dry conditions characteristically use tires without treads, often known as slicks. For example stock cars driven on professionally maintained NASCAR tracks use tires without treads, and with a thicker layer of rubber.
Front tires, especially on front wheel drive vehicles, have a tendency to wear out more quickly than rear tires. Routine maintenance including tire rotation (exchanging the front and rear tires with each other) is often done periodically to facilitate uniform tire wear. [1]
There are simple hand-held tire-pressure gauges which can be temporarily attached to the valve stem to check a tire's interior air pressure. This measurement of tire inflation pressure should be made at least once a month. Since heat in the tires from driving can impact the temperature a lot, accurate readings can only be obtained when the tires are cold - that is at least three hours after the vehicle has been driven or driven less than 1 km (1/2 mi) since cold - tire pressures will not then be higher because of operating heat. [2] The recommended inflation pressure is found in the owner's manual and on the vehicle's tire placard. [3] [4] Because of slow air leaks, changes in the weather and ambient temperature or other conditions, tire pressure will occasionally have to be corrected via the valve stem with compressed air which is often available at service stations.
Under-inflation of tires can cause premature and uneven tire wear, excess fuel usage, and carries an increased risk of explosive failure (blowout) especially after prolonged high speed operation at high temperatures. Overall, these factors decrease the life of a tire by up to 20%. [5] Many vehicles have tire pressure monitoring systems; older cars are usually equipped with indirect monitoring systems while later cars are typically equipped with direct tire pressure monitoring systems.
It is extremely important for owners to have an understanding of what is safe and what is not when it comes to their tires. The three major areas to keep an eye on is the tread, sidewall, and air pressure of the tire. Having the correct air pressure in your vehicle's tires lets your vehicle perform in the most efficient way possible. When objects such as a screw or nail puncture a tire, it creates a small leak in the tire. This leads to under-inflation of the tire. When a tire is under-inflated, it causes the inside of the tire to heat up. This heat compromises the internal structure of the tire which can lead to a blowout. When a tire is over-inflated, it wears the tread down faster, and becomes more prone to catching nails or screws in the tire. The best way to check tire maintenance is to check the air pressure, because that will lead you to whatever problem your tire might have. There are several factors that may cause quicker tire wear, among them there are heavy braking and fast cornering, constant heavy cargo transportation and rough roads, improper pressure (under- or overinflation) as the tire with low pressure cause the tire wear from the tires edges while the tire with high pressure cause the tire wear from the central part of the tire.also improper maintenance like improper tire alignment and balance cause the tire wear from one side and wearing patches along the tire. all this diffenrent types of tire wearing are called uneven tire wear pattern [6] .[ clarification needed ] That's why for the older vehicles, that do not come equipped with TPMS sensors, it is highly recommended to check tire pressure at least once a month (National Highway Traffic Safety Administration recommendation). [7] After How Many Kilometers To Change Car Tyres (Must Know to avoid accident and incident).
A disc brake is a type of brake that uses the calipers to squeeze pairs of pads against a disc to create friction. There are two basic types of brake pad friction mechanisms: abrasive friction and adherent friction. This action slows the rotation of a shaft, such as a vehicle axle, either to reduce its rotational speed or to hold it stationary. The energy of motion is converted into heat, which must be dissipated to the environment.
A tire is a ring-shaped component that surrounds a wheel's rim to transfer a vehicle's load from the axle through the wheel to the ground and to provide traction on the surface over which the wheel travels. Most tires, such as those for automobiles and bicycles, are pneumatically inflated structures, providing a flexible cushion that absorbs shock as the tire rolls over rough features on the surface. Tires provide a footprint, called a contact patch, designed to match the vehicle's weight and the bearing on the surface that it rolls over by exerting a pressure that will avoid deforming the surface.
Camber angle is one of the angles made by the wheels of a vehicle; specifically, it is the angle between the vertical axis of a wheel and the vertical axis of the vehicle when viewed from the front or rear. It is used in the creation of steering and suspension. If the top of the wheel is further out than the bottom, it is called positive camber; if the bottom of the wheel is further out than the top, it is called negative camber.
An inflatable is an object that can be inflated with a gas, usually with air, but hydrogen, helium, and nitrogen are also used. One of several advantages of an inflatable is that it can be stored in a small space when not inflated, since inflatables depend on the presence of a gas to maintain their size and shape. Function fulfillment per mass used compared with non-inflatable strategies is a key advantage. Stadium cushions, impact guards, vehicle wheel inner tubes, emergency air bags, and inflatable space habitats employ the inflatable principle. Inflation occurs through several strategies: pumps, ram-air, blowing, and suction.
A racing slick or slick tyre is a type of tyre that has a smooth tread used mostly in auto racing. The first production slick tyre was developed by M&H Tires in the early 1950s for use in drag racing. By eliminating any grooves cut into the tread, such tyres provide the largest possible contact patch to the road, and maximize dry traction for any given tyre dimension. Slick tyres are used on race tracks and in road racing, where acceleration, steering and braking require maximum traction from each wheel. Slick tyres are typically used on only the driven (powered) wheels in drag racing, where the only concern is maximum traction to put power to the ground, and are not used in rallying.
Tire rotation is the practice of moving the wheels and tires of an automobile from one position to another, to ensure even tire wear. Even tire wear extends the useful life of a set of tires, but the value of this is disputed.
Aquaplaning or hydroplaning by the tires of a road vehicle, aircraft or other wheeled vehicle occurs when a layer of water builds between the wheels of the vehicle and the road surface, leading to a loss of traction that prevents the vehicle from responding to control inputs. If it occurs to all wheels simultaneously, the vehicle becomes, in effect, an uncontrolled sled. Aquaplaning is a different phenomenon from when water on the surface of the roadway merely acts as a lubricant. Traction is diminished on wet pavement even when aquaplaning is not occurring.
The Tweel is an airless tire design developed by the French tire company Michelin. Its significant advantage over pneumatic tires is that the Tweel does not use a bladder full of compressed air, and therefore cannot burst, leak pressure, or become flat. Instead, the Tweel's hub is connected to the rim via flexible polyurethane spokes which fulfil the shock-absorbing role provided by the compressed air in a traditional tire.
A tire-pressure gauge, or tyre-pressure gauge, is a pressure gauge used to measure the pressure of tires on a vehicle. Proper tire pressure is crucial for vehicle safety, fuel efficiency, and tire longevity. Tire gauges come in various types, including analog, digital, and dial gauges, each offering different features and accuracy levels. Tire-pressure gauges can be used both professionally and casually and come in many different sizes.
Cold inflation pressure is the inflation pressure of tires as measured before a car is driven and the tires (tyres) warmed up. Recommended cold inflation pressure is displayed in the owner's manual and on the Tire Information Placard attached to the vehicle door edge, pillar, glovebox door or fuel filler flap.
A beadlock or bead lock is a mechanical device that secures the bead of a tire to the wheel of a vehicle. Tires and wheels are designed so that when the tire is inflated, the tire pressure pushes the bead of the tire against the inside of the wheel rim so that the tire stays on the wheel and the two rotate together. In situations where tire pressure is insufficient to hold the bead of the tire in place, a beadlock is needed.
A run-flat tire is a pneumatic vehicle tire designed to resist the effects of deflation when punctured, allowing the vehicle to continue to be driven at reduced speeds for limited distances. First developed by tire manufacturer Michelin in the 1930s, run-flat tires were introduced to the public market in the 1980s. They have increased in popularity over time.
A tire-pressure monitoring system (TPMS) monitors the air pressure inside the pneumatic tires on vehicles. A TPMS reports real-time tire-pressure information to the driver, using either a gauge, a pictogram display, or a simple low-pressure warning light. TPMS can be divided into two different types – direct (dTPMS) and indirect (iTPMS).
A flat tire is a deflated pneumatic tire, which can cause the rim of the wheel to ride on the tire tread or the ground potentially resulting in loss of control of the vehicle or irreparable damage to the tire. The most common cause of a flat tire is the puncturing of the tire by a sharp object, such as a nail or pin, letting the air escape. Depending on the size of the blowout, the tire may deflate slowly or rapidly.
Tire balance, also called tire unbalance or tire imbalance, describes the distribution of mass within an automobile tire or the entire wheel on which it is mounted.
A spare tire is an additional tire carried in a motor vehicle as a replacement for one that goes flat, has a blowout, or has another emergency. Spare tire is generally a misnomer, as almost all vehicles actually carry an entire wheel with a tire mounted on it as a spare rather than just a tire, as fitting a tire to a wheel would require a motorist to carry additional, specialized equipment. However, some spare tires are not meant to be driven long distances. Space-savers have a maximum speed of around 50 mph (80 km/h).
A motor vehicle service or tune-up is a series of maintenance procedures carried out at a set time interval or after the vehicle has traveled a certain distance. The service intervals are specified by the vehicle manufacturer in a service schedule and some modern cars display the due date for the next service electronically on the instrument panel. A tune-up should not be confused with engine tuning, which is the modifying of an engine to perform better than the original specification, rather than using maintenance to keep the engine running as it should.
A bicycle tire is a tire that fits on the wheel of a bicycle or similar vehicle. These tires may also be used on tricycles, wheelchairs, and handcycles, frequently for racing. Bicycle tires provide an important source of suspension, generate the lateral forces necessary for balancing and turning, and generate the longitudinal forces necessary for propulsion and braking. Although the use of a pneumatic tire greatly reduces rolling resistance compared to the use of a rigid wheel or solid tire, the tires are still typically the second largest source, after wind resistance, of power consumption on a level road. The modern detachable pneumatic bicycle tire contributed to the popularity and eventual dominance of the safety bicycle.
The Michelin PAX is an automobile run-flat tire system that utilizes a special type of rim and tire to allow temporary use of a wheel if its tire is punctured. The core of Michelin's PAX system is the semi-rigid ring installed onto the rim using special equipment. It provides support to the tire and its sidewall to allow emergency operation at limited speed until such time as the tire can be replaced. Cars that use the system include supercars like the Bugatti Veyron EB 16.4, luxury cars like the Rolls-Royce Phantom, and more common vehicles like the Honda Odyssey and Nissan Quest.
A blowout is a rapid, explosive loss of inflation pressure of a pneumatic tire.