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Tire Rotation
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. Causes of uneven tire wear The differing weight placed on the tires by the front and rear axles causes uneven wear. With the majority of cars having the engine in front, the front tires typically bear more weight than the rear tires. Front-wheel drive vehicles have not only the engine but also the transaxle in front, adding to the weight difference. Moreover, additional stress is placed disproportionately on the front tires by braking and steering. Thus, tire rotation needs to occur more frequently for front-wheel drive vehicles. Turning the vehicle will cause uneven tire wear. The outside, front tire is worn disproportionately. In countries with right-hand traffic, for example, right turns are tighter than left turns and most cloverleaf interchanges a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wheel
A wheel is a circular component that is intended to rotate on an axle Bearing (mechanical), bearing. The wheel is one of the key components of the wheel and axle which is one of the Simple machine, six simple machines. Wheels, in conjunction with axles, allow heavy objects to be moved easily facilitating movement or transportation while supporting a load, or performing labor in machines. Wheels are also used for other purposes, such as a ship's wheel, steering wheel, potter's wheel, and flywheel. Common examples are found in transport applications. A wheel reduces friction by facilitating motion by rolling together with the use of Axle, axles. In order for wheels to rotate, a Moment (physics), moment needs to be applied to the wheel about its axis, either by way of gravity or by the application of another external force or torque. Using the wheel, Sumer, Sumerians invented a device that spins clay as a potter shapes it into the desired object. Terminology The English word '':wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Popular Mechanics
''Popular Mechanics'' (sometimes PM or PopMech) is a magazine of popular science and technology, featuring automotive, home, outdoor, electronics, science, do-it-yourself, and technology topics. Military topics, aviation and transportation of all types, space, tools and gadgets are commonly featured. It was founded in 1902 by Henry Haven Windsor, who was the editor and—as owner of the Popular Mechanics Company—the publisher. For decades, the tagline of the monthly magazine was "Written so you can understand it." In 1958, PM was purchased by the Hearst Corporation, now Hearst Communications. In 2013, the US edition changed from twelve to ten issues per year, and in 2014 the tagline was changed to "How your world works." The magazine added a podcast in recent years, including regular features ''Most Useful Podcast Ever'' and ''How Your World Works''. History ''Popular Mechanics'' was founded in Chicago by Henry Haven Windsor, with the first issue dated January 11, 1902. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motor Vehicle Maintenance
An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power generation), heat energy (e.g. geothermal), chemical energy, electric potential and nuclear energy (from nuclear fission or nuclear fusion). Many of these processes generate heat as an intermediate energy form, so heat engines have special importance. Some natural processes, such as atmospheric convection cells convert environmental heat into motion (e.g. in the form of rising air currents). Mechanical energy is of particular importance in transportation, but also plays a role in many industrial processes such as cutting, grinding, crushing, and mixing. Mechanical heat engines convert heat into work via various thermodynamic processes. The internal combustion engine is perhaps the most common example of a mechanical heat engine, in which hea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vehicle Rollover
A rollover is a type of vehicle collision, vehicle crash in which a vehicle tips over onto its side or roof. Rollovers have a higher fatality rate than other types of vehicle collisions. Dynamics Vehicle rollovers are divided into two categories: tripped and untripped. Tripped rollovers are caused by forces from an external object, such as a curb or a collision with another vehicle. Untripped rollovers are the result of steering input, speed, and friction with the ground. Trailers that are not roll-coupled (i.e. those that use a trailer coupling rather than a fifth wheel) are more prone to rolling as they do not have the tractor unit or prime mover for additional stability. Untripped rollovers Untripped rollovers occur when cornering forces destabilize the vehicle. As a vehicle rounds a corner, three forces act on it: tire forces (the centripetal force), inertial effects (the centrifugal force), and gravity. The cornering forces from the tire push the vehicle towards the center ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Globe And Mail
''The Globe and Mail'' is a Canadian newspaper printed in five cities in western and central Canada. With a weekly readership of approximately 2 million in 2015, it is Canada's most widely read newspaper on weekdays and Saturdays, although it falls slightly behind the ''Toronto Star'' in overall weekly circulation because the ''Star'' publishes a Sunday edition, whereas the ''Globe'' does not. ''The Globe and Mail'' is regarded by some as Canada's " newspaper of record". ''The Globe and Mail''s predecessors, '' The Globe'' and ''The Mail and Empire'' were both established in the 19th century. The former was established in 1844, while the latter was established in 1895 through a merger of ''The Toronto Mail'' and the ''Toronto Empire''. In 1936, ''The Globe'' and ''The Mail and Empire'' merged to form ''The Globe and Mail''. The newspaper was acquired by FP Publications in 1965, who later sold the paper to the Thomson Corporation in 1980. In 2001, the paper merged with broadcast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Understeer
Understeer and oversteer are vehicle dynamics terms used to describe the sensitivity of a vehicle to steering. Oversteer is what occurs when a car turns (steers) by more than the amount commanded by the driver. Conversely, understeer is what occurs when a car steers less than the amount commanded by the driver. Automotive engineers define understeer and oversteer based on changes in steering angle associated with changes in lateral acceleration over a sequence of steady-state circular turning tests. Car and motorsport enthusiasts often use the terminology more generally in magazines and blogs to describe vehicle response to steering in a variety of maneuvers. Vehicle dynamics terminology Standard terminology used to describe understeer and oversteer are defined by the Society of Automotive Engineers (SAE) in document J670SAE International Surface Vehicle Recommended Practice, "Vehicle Dynamics Terminology", SAE Standard J670, Rev. 2008-01-24 and by the International Organization ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oversteer
Understeer and oversteer are vehicle dynamics terms used to describe the sensitivity of a vehicle to steering. Oversteer is what occurs when a car turns (steers) by more than the amount commanded by the driver. Conversely, understeer is what occurs when a car steers less than the amount commanded by the driver. Automotive engineers define understeer and oversteer based on changes in steering angle associated with changes in lateral acceleration over a sequence of steady-state circular turning tests. Car and motorsport enthusiasts often use the terminology more generally in magazines and blogs to describe vehicle response to steering in a variety of maneuvers. Vehicle dynamics terminology Standard terminology used to describe understeer and oversteer are defined by the Society of Automotive Engineers (SAE) in document J670SAE International Surface Vehicle Recommended Practice, "Vehicle Dynamics Terminology", SAE Standard J670, Rev. 2008-01-24 and by the International Organization ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snow Tire
Snow tires, also known as winter tires, are tires designed for use on snow and ice. Snow tires have a tread design with larger gaps than those on conventional tires, increasing traction on snow and ice. Such tires that have passed a specific winter traction performance test are entitled to display a 3PMSF (Three-Peak Mountain Snow Flake) symbol on their sidewalls. Tires designed for winter conditions are optimized to drive at temperatures below . Some snow tires have metal or ceramic studs that protrude from the tire to increase traction on hard-packed snow or ice. Studs abrade dry pavement, causing dust and creating wear in the wheel path. Regulations that require the use of snow tires or permit the use of studs vary by country in Asia and Europe, and by state or province in North America. All-season tires have tread gaps that are smaller than snow tires and larger than conventional tires. They are quieter than winter tires on clear roads, but less capable on snow or ice. Roadw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tire
A tire (American English) or tyre (British English) is a ring-shaped component that surrounds a Rim (wheel), wheel's rim to transfer a vehicle's load from the axle through the wheel to the ground and to provide Traction (engineering), traction on the surface over which the wheel travels. Most tires, such as those for automobiles and bicycles, are pneumatically inflated structures, which also provide a flexible cushion that absorbs shock as the tire rolls over rough features on the surface. Tires provide a footprint, called a contact patch, that is designed to match the weight of the vehicle with the bearing strength of the surface that it rolls over by providing a bearing pressure that will not deform the surface excessively. The materials of modern pneumatic tires are synthetic rubber, natural rubber, fabric, and wire, along with carbon black and other chemical compounds. They consist of a tire tread, tread and a body. The tread provides Traction (engineering), traction ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wheel Alignment
Wheel alignment sometimes referred to as breaking, or tracking is part of standard automobile maintenance that consists of adjusting the angles of wheels to the car manufacturer specifications. The purpose of these adjustments is to reduce tire wear and to ensure that vehicle travel is straight and true (without "pulling" to one side). Alignment angles can also be altered beyond the maker's specifications to obtain a specific handling characteristic. Motorsport and off-road applications may call for angles to be adjusted well beyond normal, for a variety of reasons. Primary angles The primary angles are the basic angle alignment of the wheels relative to each other and to the car body. These adjustments are the camber, caster and toe. On some cars, not all of these can be adjusted on every wheel. These three parameters can be further categorized into front and rear (with no caster on the rear, typically not being steered wheels). In summary, the parameters are: * Front: Cast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cloverleaf Interchange
A cloverleaf interchange is a two-level interchange in which all turns are handled by slip roads. To go left (in right-hand traffic; reverse directions in left-driving regions), vehicles first continue as one road passes over or under the other, then exit right onto a one-way three-fourths loop ramp (270°) and merge onto the intersecting road. The objective of a cloverleaf is to allow two highways to cross without the need for any traffic to be stopped by traffic lights. The limiting factor in the capacity of a cloverleaf interchange is traffic weaving. Overview Cloverleaf interchanges, viewed from overhead or on maps, resemble the leaves of a four-leaf clover or less often a 3-leaf clover. In the United States, cloverleaf interchanges existed long before the Interstate system. They were originally created for busier interchanges that the original diamond interchange system could not handle. Their chief advantage was that they were free-flowing and did not require t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
