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26-582: The first wheelie was reportedly performed by trick bicyclist Daniel J. Canary in 1890, shortly after modern bicycles became popular. Writing in 2009, Mike Seate related to the U.S. Army motorized cavalry training in 1943, pictured in Life magazine. Seate described "vaulting trenches and beach obstacles" and interpreted this technique as "High speed wheelies, naturally". Daredevil Evel Knievel performed motorcycle acrobatics including wheelies in his shows. Doug "The Wheelie King" Domokos has accomplished such feats as

52-418: A x {\displaystyle a_{x}} is horizontal acceleration, v x {\displaystyle v_{x}} is horizontal velocity, θ {\displaystyle \theta } is angle of vehicle from horizontal, ω {\displaystyle \omega } is angular velocity of vehicle rotation, and α {\displaystyle \alpha }

78-418: A 145-mile (233 km) wheelie. Types of wheelie can be divided into two broad categories: Wheelies are a common stunt in artistic cycling and freestyle BMX . The bicycle is balanced by the rider's weight and sometimes use of the rear brake. A style of bicycle, the wheelie bike , has a seating position, and thus center of mass , nearly over the rear wheel that facilitates performing wheelies. A wheelie

104-520: A body near the surface of the Earth is due to the combined effects of gravity and centrifugal acceleration from the rotation of the Earth (but the latter is small enough to be negligible for most purposes); the total (the apparent gravity) is about 0.5% greater at the poles than at the Equator . Although the symbol ɡ is sometimes used for standard gravity, ɡ (without a suffix) can also mean

130-544: A column of mercury of 760 mm. But since that weight depends on the local gravity, they now also needed a standard gravity. The 1887 CIPM meeting decided as follows: The value of this standard acceleration due to gravity is equal to the acceleration due to gravity at the International Bureau (alongside the Pavillon de Breteuil ) divided by 1.0003322, the theoretical coefficient required to convert to

156-673: A latitude of 45° at sea level. All that was needed to obtain a numerical value for standard gravity was now to measure the gravitational strength at the International Bureau . This task was given to Gilbert Étienne Defforges of the Geographic Service of the French Army. The value he found, based on measurements taken in March and April 1888, was 9.80991(5) m⋅s . This result formed the basis for determining

182-474: A monster truck jumps in such a way that the truck is vertical in the air, with the front end of the truck pointing upwards. Wheelies are possible with some snowmobiles , whereby it is the skis that are lifted off the ground. Some wheelchair users can learn to balance their chair on its rear wheels and do a wheelie. This enables them to climb and descend curbs and maneuver over small obstacles. Occasionally wheelchair dancers perform wheelies. In an airplane,

208-399: A wheel, neglecting air drag can be shown to be: where m {\displaystyle m} is vehicle with mass, k {\displaystyle k} is the vehicle radius of gyration , x 2 {\displaystyle x_{2}} and y 1 {\displaystyle y_{1}} are distance from rear wheel contact patch to center of mass,

234-558: A wheelie is performed by conducting a soft-field landing or take-off procedure. The pilot increases the elevator backpressure so the nose wheel of the landing gear has minimal contact with the ground. On 14 February 2020, the Guinness World Record for the longest-distance wheelie in an airplane was set in a Cessna 172 at Southern California Logistics Airport in Victorville, California on runway 17. The pilot kept

260-559: Is a motorcycle journalist, TV producer and presenter from Pittsburgh, Pennsylvania . In addition to newspaper columns, Seate has authored books and is the founder of Café Racer magazine. Café Racer (2008 to date) Velocity ( Discovery HD Theater ) This motorcycle, scooter or moped-related article is a stub . You can help Misplaced Pages by expanding it . Standard gravity The standard acceleration of gravity or standard acceleration of free fall , often called simply standard gravity and denoted by ɡ 0 or ɡ n ,

286-434: Is also a common motorcycle stunt . The principles is the same as the bicycle wheelie, but the throttle and rear brakes are used to control the wheelie while a rider uses body weight and the steering to control the direction the inertia of the spinning front wheel acting as a balance. The world's fastest motorcycle wheelie record is 307.86 km/h (191.30 mph) by Patrik Fürstenhoff . April 18, 1999. The world record for

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312-402: Is angular acceleration of vehicle rotation. This can be separated into components necessary only for horizontal acceleration and components necessary only for raising and rotating the vehicle A factor M can be calculated as the ratio of the power required to raise and rotate the vehicle and the power required only for horizontal acceleration. Mike Seate Mike Seate (born in 1965)

338-416: Is equivalent to mass times acceleration, then the minimum power required for a wheelie can be expressed as the product of mass, velocity, and the minimum acceleration required for a wheelie: Thus the minimum power required is directly proportional to the mass of the vehicle and to its velocity. The slower a vehicle is moving, the less power is required to perform a wheelie, and that is without even considering

364-426: Is illegal to perform these kinds of stunts. If someone is caught performing these acts, the rider can have their motorcycle impounded and potentially face jail time. Wheelies are common in auto- or motorcycle drag racing , where they represent torque wasted lifting the front end, rather than moving the vehicle forward. They also usually result in raising the center of mass, which limits the maximum acceleration. In

390-445: Is the horizontal distance from the rear axle to the center of mass, and h {\displaystyle h} is the vertical distance from the ground to the center of mass. Thus the minimum acceleration required is directly proportional to how far forward the center of mass is located and inversely proportional to how high it is located. Since mechanical power can be defined as force times velocity, in one dimension, and force

416-486: Is the nominal gravitational acceleration of an object in a vacuum near the surface of the Earth . It is a constant defined by standard as 9.806 65  m/s (about 32.174 05  ft/s ). This value was established by the third General Conference on Weights and Measures (1901, CR 70) and used to define the standard weight of an object as the product of its mass and this nominal acceleration . The acceleration of

442-415: Is the wheelbase, and m {\displaystyle m} is the total vehicle mass. An equivalent expression, which does not require knowing the load borne by the front wheels nor the total vehicle mass, is for the minimum longitudinal acceleration required for a wheelie: where g {\displaystyle g} is the acceleration due to gravity , b {\displaystyle b}

468-534: The newton , two units of force . Already in the early days of its existence, the International Committee for Weights and Measures (CIPM) proceeded to define a standard thermometric scale, using the boiling point of water. Since the boiling point varies with the atmospheric pressure , the CIPM needed to define a standard atmospheric pressure. The definition they chose was based on the weight of

494-399: The absence of wheelie bars, this effect is quantified in the physics section below. If wheelie bars are present then a wheelie results in a reduction of load on the rear driving wheels, along with a corresponding reduction in friction . Monster trucks often perform wheelies during shows. Monster trucks have performed power wheelies, slap wheelies, and sky wheelies. To perform a sky wheelie,

520-416: The acceleration of a body in free fall at sea level at a geodetic latitude of 45°. Although the actual acceleration of free fall on Earth varies according to location, the above standard figure is always used for metrological purposes. In particular, since it is the ratio of the kilogram-force and the kilogram , its numeric value when expressed in coherent SI units is the ratio of the kilogram-force and

546-555: The fast wheelie over 1 km (0.6 mi) is 343.388 km/h (213.371 mph), set by Egbert van Popta at Elvington airfield in Yorkshire , England. In some countries, such as the United Kingdom and USA, motorcyclists performing a wheelie on a public road may be prosecuted for dangerous driving , an offense which can carry a large fine and a ban of a year or more. In Pakistan, India, and some other countries, it

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572-453: The local acceleration due to local gravity and centrifugal acceleration, which varies depending on one's position on Earth (see Earth's gravity ). The symbol ɡ should not be confused with G , the gravitational constant , or g, the symbol for gram . The ɡ is also used as a unit for any form of acceleration, with the value defined as above. The value of ɡ 0 defined above is a nominal midrange value on Earth, originally based on

598-460: The plane's nose wheel from touching the runway for a distance of 14,319 feet. A wheelie bar helps prevent a vehicle's front end from raising too high or flipping over. A bar is required for some tractor and truck pull events. Wham-O developed and sold an add-on wheelie bar for wheelie bikes . A wheelie is imminent when the acceleration is sufficient to reduce the load borne by the front axle to zero. The conditions for this can be calculated with

624-489: The power required to overcome air drag , which increases with the cube of velocity. Therefore, the least amount of power required is when the vehicle begins accelerating from rest. In the case of tractor and truck pulling, the force to the pull the load is applied above the ground, and so it also acts to lift the front wheels and thus reduces the forward acceleration necessary to lift the front wheels. The total power P {\displaystyle P} required during

650-429: The so-called "weight transfer equation": where Δ W e i g h t f r o n t {\displaystyle \Delta Weight_{front}} is the change in load borne by the front wheels, a {\displaystyle a} is the longitudinal acceleration, h {\displaystyle h} is the center of mass height, w {\displaystyle w}

676-502: The value still used today for standard gravity. The third General Conference on Weights and Measures , held in 1901, adopted a resolution declaring as follows: The value adopted in the International Service of Weights and Measures for the standard acceleration due to Earth's gravity is 980.665 cm/s , value already stated in the laws of some countries. The numeric value adopted for ɡ 0 was, in accordance with

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