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The "All-Terrain Vehicle" or ATV in North America (quad-bike or quad elsewhere) is used in a general sense to describe any of a number of small open motorized buggies and tricycles designed for off-road use. However, the American National Standards Institute (ANSI) defines an ATV as a vehicle that travels on low pressure tires, with a seat that is straddled by the operator, and with handlebars for steering control. By the current ANSI definition it is intended for use by a single operator, although a change to include 2-seaters (in tandem) is under consideration.[1]
The rider sits on and operates these vehicles like a motorcycle, but the extra wheels give more stability at slow speeds. Although typically equipped with three or four wheels, six-wheel models exist for specialized applications. Engine sizes of ATVs currently for sale in the United States (as of 2008 products) range from 49 cc to 950 cc.
Contents [hide]
1 Development
1.1 Early days
1.2 Three wheelers
1.3 Four wheelers
1.4 Racing models
2 Criticisms of ATVs
2.1 Safety Issues in U.S.
2.2 U.S. EPA Concerns
2.2.1 Emissions
2.3 Land Usage
3 Major Manufacturers of ATVs
4 See also
5 References
6 External links
[edit] Development
[edit] Early days
ATVs were made in the United States a decade before 3- and 4-wheeled vehicles were introduced by Honda and other Japanese companies. During the 1930s numerous manufacturers offered similar small off-road vehicles that were designed to float and were capable of traversing low walls, ponds and streams as well as dry land. Typically constructed from a hard plastic or fiberglass "tub", they usually had six wheels—all driven—with low pressure (around 3 PSI) balloon tires, no suspension (other than what the tires offered) and skid-steer steering. These early amphibious models were the original all-terrain vehicles—or ATVs. Contrary to today's ANSI definition of an ATV, they were intended for multiple riders, sitting inside, and would usually have steering wheels or control sticks rather than motorcycle-type handle bars as stipulated in the current definition.
Since the advent of three- and four-wheeled, straddled ATVs, these have more or less 'taken over' the term, leaving the 6x6 and 8x8 floating variety now mostly known as AATVs (Amphibious All-Terrain Vehicles). Current brands of these machines include Argo and MAX. Though not as fast as other ATVs, they can be operated with precision at slow speeds and, of course, have the ability to float. The spinning action of the tires is enough to propel the vehicle through the water, albeit slowly. Outboard motors can be added for extended water use.
[edit] Three wheelers
Honda made the first three-wheeled ATVs in 1970, which were famously portrayed in the James Bond movie, Diamonds Are Forever. Dubbed the US90 and later—when Honda acquired the trademark on the term[2]—the ATC90, it was designed purely for recreational use. Clearly influenced by earlier ATVs, it featured large balloon tires instead of a mechanical suspension.[3]
By the early 1980s, suspension and lower-profile tires were introduced. The 1982 Honda ATC200E Big Red was a landmark model. It featured both suspension and racks, making it the first utility three-wheeled ATV. The ability to go anywhere on terrain that most other vehicles could not cross soon made them popular with US and Canadian hunters, and those just looking for a good trail ride. Soon other manufacturers introduced their own models.
Sport models were also developed by Honda, which had a virtual monopoly in the market due to effective patents on design and engine placement. The 1981 ATC250R was the first high-performance three-wheeler, featuring full suspension, a 248 cc two-stroke motor, a five-speed transmission with manual clutch and a front disc brake. For the sporting trail rider, the 1983 ATC200X was another landmark machine. It has an easy-to-handle 192 cc four-stroke that was ideal for new participants in the sport.
Over the next few years all manufacturers, except Suzuki, developed high performance two-stroke engined machines to compete against Honda's monopoly, in the market, but did not sell as many due to the reputation already secured by Honda. These models were the Yamaha Tri-Z YTZ250 with a 246 cc two-stroke engine a manual clutch and 5- or 6-speed gearbox, and the Kawasaki Tecate KXT250 with a 249 cc two-stroke with 5-speed gearbox and a manual clutch. Other smaller or lesser known companies such as Tiger ATV, Can Am, Franks and Cagiva produced racing three wheelers, but in much smaller numbers. Few of these machines are known to exist today and are highly sought by collectors.
[edit] Four wheelers
Suzuki was a leader in the development of 4-wheeled ATVs. It sold the first ATV, the 1982 QuadRunner LT125, which was a recreational machine for beginners.
In 1985 Suzuki introduced to the industry the first high-performance 4-wheel ATV, the Suzuki LT250R QuadRacer. This machine was in production for the 1985-1992 model years. During its production run it underwent three major engineering makeovers. However, the core features were retained. These were: a sophisticated long-travel suspension, a liquid-cooled two-stroke motor and a fully manual 5-speed transmission for 85–86 models and a 6-speed transmission for the 87–92 models. It was a machine exclusively designed for racing by highly skilled riders.
Honda responded a year later with the FourTrax TRX250R—a machine that has not been replicated. Kawasaki responded with its Tecate-4 250.
In 1987, Yamaha introduced a different type of high-performance machine, the Banshee 350, which featured a twin-cylinder liquid-cooled two-stroke motor from the RD350LC street motorcycle. Heavier and more difficult to ride in the dirt than the 250s, the Banshee became a popular machine with sand dune riders thanks to its unique power delivery. The Banshee remains hugely popular, but 2006 is the last year it will be available in the U.S. (due to EPA emissions regulations).
In Canada, however, the Banshee will be back for the 2007 model year, still featuring the same parallel-twin, 350 cc, two-stroke engine that made the machine famous.
Shortly after the introduction of the Banshee in 1987, Suzuki unleashed a bombshell of its own with the release of the LT500R QuadRacer. This unique quad was powered by a 500 cc liquid cooled two stroke engine with a 5-speed transmission. This ATV earned the nickname "Quadzilla" with its remarkable amount of speed and size. While there are claims of 100+ mph stock Quadzillas, it was officially recorded by 3&4 Wheel Action magazine as reaching a top speed of over 79 mph (127 km/h) in a high speed shootout in its 1988 June issue, making it the fastest production ATV ever produced to this day. Suzuki discontinued the production of the LT500R in 1990 after just 4 years. By doing so, the rare Quadzilla is a common topic of ATV folklore and legend.
At the same time, development of utility ATVs was rapidly escalating. The 1986 Honda FourTrax TRX350 4x4 ushered in the era of four-wheel drive ATVs. Other manufacturers quickly followed suit, and 4x4s have remained the most popular type of ATV ever since. These machines are popular with hunters, farmers, ranchers and workers at construction sites.
Safety issues with 3-wheel ATVs caused all manufacturers to switch to 4-wheeled models in the late '80s, and 3-wheel models ended production in 1987, due to consent decrees between the major manufacturers and the Consumer Product Safety Commission—the result of legal battles over safety issues among consumer groups, the manufacturers and CPSC. The lighter weight of the 3-wheel models made them popular with some expert riders. Cornering is more challenging than with a 4-wheeled machine because leaning into the turn is even more important. Operators may roll over if caution isn't used. The front end of 3-wheelers obviously has a single wheel, making it lighter, and flipping backwards is a potential hazard, especially when climbing hills. Rollovers may also occur when traveling down a steep incline. The consent decrees expired in 1997, allowing manufacturers to, once again, make and market 3-wheel models, though there are very few marketed today.
Models continue, today, to be divided into the sport and utility markets. Sport models are generally small, light, two wheel drive vehicles that accelerate quickly, have a manual transmission and run at speeds up to 90 miles per hour (145 km/h). Utility models are generally bigger four-wheel drive vehicles with a maximum speed of up to 72.5 miles per hour (104 km/h). They have the ability to haul small loads on attached racks or small dump beds. They may also tow small trailers. Due to the different weights, each has advantages on different types of terrain.
It has been surprising to the manufacturers the ingenuity of many people in adapting their quads to farming needs.
Six wheel models often have a small dump bed, with an extra set of wheels at the back to increase the payload capacity. They can be either 4-wheel drive (back wheels driving only), or 6-wheel drive.
ATV racing on a motocross trackATV also refers as Quad or Four-wheelers or All-terrain-vehicle.
[edit] Racing models
Sport models are built with performance, rather than utility, in mind. To be successful at fast trail riding, an ATV must have light weight, high power, good suspension and a low center of gravity. These machines can be modified for such racing disciplines as motocross, woods racing (also known as cross country), desert racing (also known as Hare Scrambles), hill climbing, ice racing, speedway, Tourist Trophy (TT), flat track, drag racing and others. Examples of high-performance models(racing) include the Yamaha YFZ450, Honda TRX450R. ,Suzuki QuadRacer R450, Kawasaki KFX450R, Can-Am DS450,Polaris Outlaw 525 S,Outlaw 450 MXR and the no longer produced Honda TRX250R. ATVs designed for fast trail riding include the Yamaha Raptor 700R/660R,Suzuki QuadSport Z400, Yamaha Raptor 350, Kawasaki Mojave 250, Kawasaki Lakota Sport 300, Honda Sportrax 400EX, Kawasaki KFX400,Bombardier/Can-Am DS650, Can-Am DS-450,Arctic Cat DVX400, Polaris Scrambler 500, Polaris Outlaw 500, Polaris Outlaw 525 (independent rear suspention IRS), Kawasaki KFX700, Polaris Predator 500 and Can-Am Renagade 800. Three wheeled performance models included the Honda ATC250R (1981-1986), Yamaha YTZ250 Tri-Z (1985-1986), Kawasaki KXT250 Tecate (1984-1987), and the Tiger 250 and 500 (mid 1980's). Three Wheelers designed for fast trail riding include the Honda ATC350X and the Honda ATC200X.
[edit] Criticisms of ATVs
Since the late 1980s, ATVs have been associated with illegal youth activity such as underage drinking. This has led to greater conflict between ATV users and child-safety advocates, rural landowners, fellow outdoor recreationalists and environmentalists.
[edit] Safety Issues in U.S.
Since the expiration of the consent decrees between the major manufacturers and CPSC in April of 1998, the manufacturers have entered into "voluntary action plans" that mimic the previously mandatory consent decrees. However, despite the move from 3-wheel to 4-wheel models and the action plans, some deaths and injuries still occur. Statistics released by CPSC show that in 2005, there were an estimated 136,700 injuries associated with ATVs treated in US hospital emergency rooms. In 2004, the latest year for which estimates are available, 767 people died in ATV-associated incidents. According to statistics released by CPSC, the risk of injury in 2005 was 171.5 injuries per 10,000 four-wheel ATVs in use. The risk of death in 2004 was 1.1 deaths per 10,000 four-wheelers in use.[4]
Focus has shifted since the consent decrees ended to attention to machine size balanced with the usage of ATVs on state run land categorized by age ranges and engine displacements—in line with the consent decrees. ATVs are mandated to be labeled from the manufacturer that the use of machines greater than 90 cc by riders under the age of 12 is prohibited.
Critics point out that blanket policies concerning age are not sufficient and often use, as example, that early-teen male children are physically larger and stronger than many adult women riders. Some Locations have either banned minors (typically those under 12 years of age) from using ATVs or are considering such legislation. Advocates of ATVs argue that starting younger improves safety. They recommend that children can develop the necessary expertise by starting at as young as 6 years of age instead of waiting until age 18. The U.S. Consumer Product Safety Commission approved the sale of sub-50cc ATVs for use by youngsters as young as age 6.
In 1988, the All-terrain Vehicle Safety Institute (ASI) was formed to provide training and education for ATV riders. The cost of attending the training is minimal and is free for purchasers of new machines. Successful completion of training such as provided here is in many states a minimum requirement for minor-age children to be granted permission to ride on state land.
According to the New York Times September 2, 2007, the Consumer Product Safety Commission met in March 2005 to discuss the dangers of ATVs. Data from 2004 showed 44,000 children under 16 injured while riding ATVs, 150 of them fatally.[5] Says the Times, "National associations of pediatricians, consumer advocates and emergency room doctors were urging the commission to ban sales of adult-size A.T.V.’s for use by children under 16 because the machines were too big and fast for young drivers to control. But when it came time to consider such a step, a staff member whose name did not appear on the meeting agenda unexpectedly weighed in."
That staff member was John Gibson Mullan, "the agency’s director of compliance and a former lawyer for the A.T.V. industry" - the Times bases the claim on a recording of the meeting. He said that the existing system of warnings and voluntary compliance was working.
The agency's hazard statistician, Robin Ingle, was not allowed to present a rebuttal. She told the Times in an interview, "“He had hijacked the presentation. He was distorting the numbers in order to benefit industry and defeat the petition. It was almost like he still worked for them, not us.”
[edit] U.S. EPA Concerns
[edit] Emissions
Due to the lack of emission controlling hardware and software, for year 2000 all recreational spark-ignited (SI) non-road vehicles (of which ATVs are a subset) contributed 8% of HC, .16% of NOx, 5% of CO and .8% of PM emissions for the entire non-road US EPA family. The entire range of non-road emissions accounted for 49% of engine produced emissions of all types.[6] While recreational SI vehicles produce an aggregate of <4% of all HC emissions in the US, based on the relatively small population of ATVs (<1.2M) and small annual usage (<350 hrs), EPA emission regulations now include such engines, starting with model year 2006.[7]
In Minnesota alone it is projected there will be more than 1 million registered ATVs by 2010. There are about 300,000 in the state now.
[edit] Land Usage
Some countries where fencing is not common, such as the US, Canada and Australia, ATV riders knowingly cross privately owned property in rural areas and travel over public/private properties where their use is explicitly limited to trails. Subsequently, environmentalists criticize ATV riding as a sport for excessive use in areas environmental-movement-friendly biologists consider to be sensitive, especially wetlands and sand dunes; and in much of inland Australia.
While the deep treads on some ATV tires are effective for navigating rocky, muddy and root covered terrain, these treads also dig channels that may drain boggy areas, increase sedimentation in streams at crossings and damage groomed snowmobile trails. Studies have also shown that ATVs may help in the spread of invasive species such as knapweed and Lantana. Despite some limited studies showing the impacts of unregulated ORV use, the vast majority of ORV use on public lands is regulated. Moreover, running counter to the popular misconception that ATV and ORV use is a leading cause of damage to the landscape and sensitive habitats in general, the overwhelming evidence of human growth patterns upon the landscape indicates damage to the sensitive habitats is caused by unmitigated growth of single-family housing planning and extractive industries.
Bank erosion started by four wheeler All-terrain vehicles, Yauhanna, South Carolina.ATV advocacy groups have been organized to purchase property or obtain permission of landowners, or both. Many US states pay the clubs to build and maintain trails suitable for ATV riding and educate ATV riders about responsible riding. Many have also formed separate governing bodies that license ATVs separately than other ORVs. The monies from gas taxes and registrations are used to create more trails to ride and to perform grooming and maintenance.
Self-regulation has proven particularly difficult. One public complaint against ATVs is excessive noise. Although the majority of ATVs comply with noise regulations, there are those whose intentional violation can disturb the activities of other recreational users for miles across open landscapes. Tampering with an ATVs exhaust silencer and spark arrestor is illegal on all US federal lands and most state lands. However, enforcement is spotty. It is also possible to install after-market exhaust systems that do not have spark arrestors.
Further, off-road vehicles, including ATVs, frequently go off designated trails, thus creating new spur trails. This process is called trail proliferation. In areas where the vehicles are confined to designated trails, enforcement is fairly straightforward, however some states have laws that permit use on vaguely defined, undesignated trails.
Fellow outdoor recreationalists who have expressed concern about irresponsible ATV use include snowmobile users who resent improper use of exclusive snowmobile trails, ATV trail-riders whose trails have been damaged by improper use, and hunters whose game has been driven off by those riding during prime hunting times.
Nationally, the US Forest Service considers managed ATV use to be a legitimate activity in national forests, yet it also lists their unregulated use as one of the four greatest threats to long-term forest management. The US Forest Service recently released a national travel management plan designed to minimize the negative environmental impacts of ATVs while providing a safe, sustainable and enjoyable opportunity for ATV users.
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