A quad (to lat. Quadri- "quad") or ATV (all terrain vehicle) is a small motor vehicle for one to two people with four wheels or, more rarely, four tracks, often with thick balloon tires as an off-road vehicle.
Quads are sport vehicles, ATVs on the other hand are more like working machines and are intended for extreme off-road use (4×4). this distinction, which is common for germany, is not valid everywhere. in canada or the USA the designation quad or ATV is synonymous. The driver’s seat of the quad and most atvs is saddle-shaped, the steering is operated by a steering rod. In the side-by-side vehicles, which are derived from the atvs and are still rare, seats are installed similar to the car seat, and the steering is operated by a steering wheel. But it is also possible to ride the ATV and the side-by-side vehicle quite sporty. As a motor vehicle, these vehicles can serve as both a fun and a work tool. ATVs and side-by-side vehicles are also used for passenger transport by the military, for which these vehicles were originally developed.
Table of contents
the ur-quad was designed in germany in 1962 by the company faun for the german army. it was the power cart, called "KRAKA. However, no successor to this model was developed.
The forerunners of the quads of the recent past were three-wheeled motorcycles, originally developed by honda all-terrain (motor)cycles (ATC.). They were also called tri-Z. Sales market was the USA, where the vehicles appeared first. the three-wheelers were initially intended only as fun vehicles for the southern californian deserts.
the chassis geometry of these three-wheelers takes a lot of getting used to. The engine power is transmitted to a rigid rear axle without a swing arm, on which most of the rider’s weight is also borne. the front wheel is hardly loaded at all, in fact it is really relieved of load when the throttle is applied. controlled steering movements are therefore almost impossible. A chassis suspension was not installed. This task had to be performed exclusively by balloon tires. The consequences of this very simple and immature design were numerous serious accidents in the USA. Consumer advocates finally succeeded in getting a ban on the sale of these three-wheelers. However, as the market seemed to be too lucrative, the suzuki company made the vehicles less complex, added a fourth wheel and created the first quad, the suzuki LT 125. Over time, the structure of the vehicles, for example, the suspension or the engines, has been further improved. They were first used by farmers for work on their large pastures, then as a transport vehicle and later also as a sporting machine. In the sports sector, the quad continues to gain ground, and official quad championships are now held in many countries.
Quads usually have a rigid rear axle that is torsionally stiff relative to the frame and is guided by a swing arm. This type of construction has proven itself over the years. On the one hand, it provides a certain degree of cornering stability, but on the other hand, it prevents the use of a differential gear, as the inside rear wheel loses static friction with the road surface. This can even lead to a loss of contact between the road and the tire, with differential gears traction would be lost, the drive would only act on the free tire. Slippage on one rear wheel is necessary in this design, it allows the small four-wheelers to corner.
On the ATV, however, an independent suspension on double wishbones on the rear axle is slowly gaining acceptance, although a differential gear is usually not used here either. Due to the large balloon tires with low inflation pressure, the pressure of the tires on the ground is lower than the typical quad, which keeps the tire wear reasonably in check. The independent suspension allows for greater interlocking of the individual axles, which provides significant advantages over a rigid axle when working in heavy terrain or on an enduro trail. In motocross sport, this design (so far) does not bring any tangible advantages. In addition, an independent suspension is heavier and requires more maintenance than the swingarm design.
The front wheels of both the quad and the ATV are guided by double wishbones, known in the trade as A-arms. In the case of ATV all-wheel drives, a lockable differential gear is installed here.
For suspension damping in modern sportquads, high performance dampers are installed on the front and rear axles, which are fully adjustable in rebound and compression. Many shocks have a separate pressure reservoir, which, in addition to absorbing the displaced oil during compression, also serves to cool the shock oil. most premium brand sportquads have a die cast aluminum rear swingarm. This is lighter than forged or welded steel swingarms. Together with aluminum rims, this results in a significant reduction of the unsprung mass on the rear axle.
Yamaha offers in its model grizzly 700 as the first OEM (Ooriginal Eequipment Manufacturer) offers power steering. the advantages of electronic power steering are noticeable on this heavy ATV even in normal operation. If the ATV is equipped with a crawler chassis is the advantage very large, because without steering assistance by the high rolling resistance of the tracks high steering forces are to be applied by the driver.
Quads are stopped with disc brakes on the front and rear axles which are actuated hydraulically (via multi-piston brake calipers) or mechanically (via Bowden cable). High-quality machines also have steel-flex brake lines. The drum brake is no longer up to date and is only used on inferior machines. kawasaki has taken a special approach with an encapsulated oil-bath multi-disc brake on the rear axle of its atvs and the KFX700.
the frames of the premium sportquads are usually hybrid frames made of steel and aluminum with a high torsional stiffness. Kawasaki offers a complete frame in aluminum in its KFX-450. The DS 450 EFI from CAN-AM (new brand name for bombardier atvs and quads) also has an aluminum frame with an innovative pyramid design. The complete frame has no welds and is held together with aluminum bolts and screws so that the skeleton with fewer parts could be built more stable than conventional frames. the total weight of the frame is only 16.7 kg.
For racing purposes, additional nerv bars, a steering damper, a kill-switch (this is a breakaway line that stops the engine when the rider is separated from the vehicle), all kinds of engine tuning parts and widened front and rear axles can be installed. A track widening is also suitable, together with a lowering, to convert a quad to a good road vehicle. Of course, it is also recommended to change from the standard off-road tires to street tires. Over the last few years a good dealer network has developed in Germany, so that the acquisition of good components, compared to the beginning of the quad boom, is no longer a problem.
The motorization of the vehicles is currently between 50 cm³ and 800 cm³ (and about 50 kw). There are also some "extreme" special designs with up to 1150 cm³ displacement or additional turbochargers. The engines are usually four-stroke single cylinders. There are also models with four-stroke two-cylinder or two-stroke engines. probably the most famous quad with a two-stroke engine is the yamaha banshee (type designation YFZ 350), which was produced over 18 years and dominated the sports scene in the USA and europe for a long time.
In 2007, the manufacturer arctic cat launched an ATV with a diesel engine. Since polaris failed a few years ago with the attempt to establish a diesel ATV in the market, arctic cat is currently the only ATV OEM with a diesel aggregate.
In the area of mixture preparation, the changeover from classic carburetors to electronic injection systems is becoming apparent. This is mainly done to improve the performance and running culture of the engines, but also to reduce the pollutant emissions of the vehicles.
The power transmission to the drive axle of the quad is usually done by a chain, while especially on the ATV’s equipped with selectable all-wheel drive, a low-maintenance and low-wear cardan drive is mainly used. Changing the gear ratio of the cardan drive is only possible with a great deal of effort. In the case of chain drive, the ratio can be changed very easily by changing the sprockets.
Classically, quads are shifted by a manual foot shift, comparable to that of a motorcycle. the reverse gear, if available, is engaged by a separate switch or lever. In the entry-level segment, automatic shifting by means of belt variators (CVT) has become increasingly popular in recent years. this has been standard for atvs for years. As with automobiles, sport riders are very skeptical about automatic transmission, which is why the number of sport quads with CVT transmission is small.
For safety reasons, a thumb throttle is installed on the vehicles as well as on jet skis or snowmobiles. A throttle twist grip can be retrofitted, but this makes precise throttle control difficult due to the relatively high steering forces. When the rider’s weight shifts, the risk of accidental acceleration increases significantly. A rotary throttle therefore offers no advantages over the thumb throttle, apart from greater comfort on longer road trips.
 street legal
The vehicles are usually imported to europe as pure off-road vehicles and must be extensively tested by the importers or dealers for road registration. dealers can be retrofitted. During the conversion, the headlights, turn signals, brake lights, parking lights and speedometer are installed according to EC standards.
Mainly affected by these conversion measures are the high-displacement machines of the premium brands such as z. B. Yamaha, kawasaki, polaris or CAN-AM which, according to German law, can only be legally put on the road as agricultural tractors. Thus, in addition to the measures described above, a second main lighting system and a trailer hitch must be fitted to these sporting machines. But this type of homologation has an advantage. since quads usually have gasoline engines (with the exception of one machine from arctic cat), there is no need for an emissions test, since there are no limits for gasoline engines in this registration category.
Many machines in the entry-level class up to 300 cc, especially those from Taiwanese and Chinese manufacturers such as Kymco or SMC, are supplied as standard with COC papers (EU homologation) and attachments that comply with the EU standard. So a problem-free registration as a VKP is possible. The COP papers are valid throughout the EU, so that z. B. A machine with first registration in germany can also be registered there after a sale to another EU country. this is not possible with a tractor license.
Quads are by definition not "two-wheelers", so in germany the driving license class B (until 1998: class 3) as required for passenger cars. the minimum age to buy and drive on public roads is 18 years, regardless of the capacity or power of the vehicle. Due to the sharp rise in registration numbers, on 1. February 2005 the national EU driving license class S introduced, which also allows 16-year-olds to ride quads with a displacement of up to 50 cm³ (insurance license plate).
With the registration, depending on the importer or customer request at the dealer, a distinction is made in germany:
- tractor.(ZM) the advantage of the tractor registration is the registered full power of the machine. This is mostly done for high horsepower and high displacement machines.
- 4-wheeled vehicle for passenger transport (VKP). Here is a maximum registered power of 20 hp (15 KW) possible. an exhaust emission test must be carried out for the main inspection.
For the acceptance according to § 21 stvzo is only the technical inspection authority responsible. In principle, quads may only be driven on public roads. Driving on forestry roads requires prior approval. it is forbidden to drive motorized vehicles in the open countryside (§ 56 bnatschg, article 21, paragraph 2, article 23 baynatschg).
However, the tractor registration does not play a role in the vehicle tax. the classification of the tax seems to depend on the responsible tax office. most of the time a cubic capacity dependent taxation is applied for passenger cars.
According to the wording of annex 3, to the traffic bans according to § 40 abs. 1 of the federal immission control act  , tractor units (ZM) are exempt from the obligation to be registered in environmental zones.
Quads and atvs with a displacement of more than 50 cc are usually classified as passenger cars for insurance purposes, and not as motorcycles, as many people erroneously assume. the lowest insurance level is 100!
However, there are some insurers who offer a special (favorable) insurance class for quads. A price comparison is therefore advisable.
in austria and germany, quads with a displacement of up to 50 cm³ can be ridden as a moped with a red license plate from the age of 16 with a moped license; for all larger vehicles, a motorcycle or car license is required in austria. Therefore, they can also be classified according to the type of license plate (one or two lines) with motorcycle or register car on changeable license plate. If it is one that is still registered as a tractor, a class "F" driver’s license is also sufficient, and it can be driven from 16, it may then not drive faster than 50 km / h.
the quads are licensed as small motor vehicles of class A2 regardless of the engine size. Therefore, holders of a category B driver’s license (car) as well as category A (motorcycles over 11 kW power) or A1 (motorcycles up to and including 125 cm³ and 11 kW power) may drive quads.
Deviating from the other small motor vehicles of the class A2 exists since 1. February 2006 a helmet wearing obligation.
The brake lever on the handlebars is modified for swiss registration so that it acts on all four wheels, with a braking force distribution of 60 % on the front and 40 % on the rear.
in spain, quads up to 50 cm³ can be ridden from the age of 14 with a moped license. For all higher motorized quads a class B license is also sufficient. But here is absolute helmet obligation. The applicable EU law (helmet obligation only if it is entered in the vehicle registration document) is not of interest here. the penalty for quad driving without helmet is 63 euro.
on mallorca the registration numbers of quads are increasing rapidly. All manufacturers are represented, whereby it is noticeable that strongly motorized machines (400-750 cm³) are on the advance. The quad is a very suitable means of transport on mallorca with about 300 sunny days a year.
 helmet compulsory
Since 21. december 2005 the german Bundesrat passed a resolution at short notice making helmets compulsory in germany. "Anyone driving motorcycles or open-top three- or multi-wheeled motor vehicles with a maximum design speed of more than 20 km/h, or riding on or in them, must wear a suitable safety helmet while driving." so far the 40. Regulation amending the road traffic regulations from 21. December 2005, which comes into force immediately. This puts the riders of quads and ATVs on an equal footing with scooter and motorcycle riders.
In austria, since october 2002, all four-wheeled motor vehicles with a design speed of more than 25 km/h, which have the characteristics of a motorcycle, in particular due to the handlebars, control and display elements and the bench seat, so helmets are compulsory for all quads and atvs regardless of engine size, analogous to trikes and sidecars.
From the 1. January 2006 applies in germany, from 1. february 2006 in switzerland a general helmet obligation for quads and atvs. Everybody has to wear a helmet when riding, no matter if it is written in the vehicle registration or not.
In addition to the compulsory use of helmets, an approved first-aid kit and a warning triangle must also be carried on the vehicle. These are now easily available from the major mail order companies, usually adapted to the special space conditions of quads and atvs. The non-carrying leads just like the non-wearing of a helmet at controls to a chargeable warning.
 riding behavior
quads and especially atvs are usually designed as offroad vehicles and have a rather high center of gravity due to the ground clearance needed for offroad driving. this high center of gravity, together with incorrect posture of the rider, can cause the vehicle to tip over when cornering quickly or riding across a slope. In the meantime, however, quads have been developed to be more "roadworthy" in order to reduce such risks. This development naturally has less impact on atvs as work machines. As before, during sudden strong acceleration, the front axle is partially unloaded to the point of losing contact with the ground, the vehicle is then temporarily no longer steerable. This can be avoided by applying the throttle in a controlled manner.
Quads and atvs have a driving behavior all their own. It is not to be compared with that of a car or a motorcycle. Many accidents are due to overestimation and a lack of knowledge about the driving characteristics of quads and atvs. Since – as with most motorcycles – the protective bodywork is missing, the consequences of an accident are similarly severe. In addition to a good safety helmet, it is therefore essential to wear other personal protective equipment: body protection (corresponding to motorcycle clothing), protective gloves that do not chafe or even melt when dragging on the road, and sturdy footwear. but in the meantime there are also hardtops for atvs that can be retrofitted. Since the 90s of the last century, there are alternatively the so-called side-by-side vehicles like the tomcar or the yamaha rhino. this ATV-family mostly has a roof or a roll bar.
because of the special riding behavior of atvs and quads, participation in a rider training course is recommended. In these training sessions, the rider is taught.A. The correct basic body postures for different riding situations such as e.B. Starting, cornering, going uphill/downhill or crossing a slope shown. A posture adapted to the riding situation is very important. Quads have a tare weight of between 142 and 220 kilograms. An average driver with a body weight of 85 kilos makes approx. The rider accounts for one third of the total vehicle weight and can have a considerable influence on the vehicle’s center of gravity and thus on the riding behavior of the quad with his or her posture.
These training courses are available from various organizers at different stages of development. In the categories of beginner, advanced, etc., the traditional dealership will become less important. As well as the specials like enduro or jump training, every quad rider will find the right thing for him to improve his riding skills.
 competitions and events
In germany, a very active community of quad riders has developed which comes together for various events and motorsport events. In motorsport, there are the following categories and series: