Motor-paced racing
Motor-paced racing and motor-paced cycling refer to cycling behind a pacer in a car or more usually on a motorcycle. The cyclist (or stayer in this case) follows as close as they can to benefit from the slipstream of their pacer. The first paced races were behind other cyclists, sometimes as many as five riders on the same tandem. Bordeaux-Paris and record attempts have been ridden behind cars. More usually races or training are behind motorcycles. Origins of pacing. Cyclists started to use tandem bicycles as pacers in the late 19th century. There could  be as many as five riders on the pacing machine. Because of the long distances covered when following a pacer, these cyclists were called stayers, a term used in long-distance horse racing. Companies such as Dunlop sponsored pacing teams, and "tens of thousands" turned out to watch. A south London rider, J. W. Stocks, set British record of in an hour behind a Dunlop quintuplet on 27 September 1897. The pacing tandems were ridden by professionals, of whom as many as 100 were under contract. Each competitor had six to eight pacing teams for races between . Speeds rose when  engines were added to pacing tandems. Arthur Chase and the Frenchman Émile Bouhours set English records behind powered tandems in 1898 and 1899. Chase used a motorcycle to pace him to in a private test at The Crystal Palace, south London, in July 1900 but riders in the USA and in Paris had already done better. Some races mixed pacing with solo bicycles, tandem and motorcycle, with the riders given different start points in compensation. Pacing by car. Bordeaux–Paris, a race of nearly from south-west France to the capital, was paced part of the way by cars in  1897, 1898 and 1899. So was Paris–Roubaix. The historian Pierre Chany said: "Cars made only a brief appearance in Paris–Roubaix. On the roads of the north, these noisy cars, high with wooden wheels with their tires nailed in place, raised huge clouds of dust. The drivers, wearing leathers, their eyes protected by huge goggles, were stepping into the unknown! The riders hidden in all this chaos could see absolutely nothing and risked their life at on the edge of a razor. The noise was infernal and the column advanced in the stink of exhaust pipes." Pacing by motorcycle . The first races were limited more by the speed a motorcycle could achieve than the ability of the rider to follow, with being a good average, according to the historian H. M. Ellis. The races became faster as the pacers became faster. Paced races kept audiences enthralled for many decades in Europe and, at one time, in North America. Tens of thousands watched, especially in Germany. The popularity of this form of pacing declined in the latter part of the 20th century. There were few rules. Pacing machines had small rollers set sideways behind the back wheel to avoid crashes  caused by the rider touching the back of the motorcycle, but there were few other regulations. Race distances extended to six days, although one-hour and contests were more common. Windshields were briefly allowed but abandoned after the world championship in 1904. Speeds rose and accidents became commonplace. An American, Harry Elkes, died of his injuries from a crash in front of 10 000 spectators at Boston, Massachusetts, USA. His rear tire exploded at and he was thrown under another rider's pacing machine, which "crushed the prostrate man in a dreadful manner." George Leander of Chicago said, "Only the  clumsy get themselves killed" before starting a race at the Parc des Princes in Paris. Leander was thrown into the air after , fell to the track, bounced into the seating and died 36 hours later. A crash in Berlin on 18 July 1909 killed nine when a motorcycle careered into the stands and exploded. The historian Peter Nye wrote: The biggest machines were built by the pacers, using parts from other motorcycles, with engines as large as . The largest had two riders, one crouched over the handlebars to steer and the other sitting upright above the back wheel to protect  the rider and to operate the engine. The pacers wore leathers, goggles and helmets but many riders wore a flat cap. The world governing body, the Union Cycliste Internationale, set regulations for pacing motorcycles in 1920. Until then standards had been set by the police, particularly in Germany, or by the track promoters. World championships were held annually, except during wars, for 100 years, often separately for amateurs and professionals. Carsten Podlesch, who won in 1994, is the last and reigning world champion. National championships continue in several European countries and European championships are conducted annually. Motorcycles now used include  the Triumph Tiger or BMW machines. The motorcycle for motor-pacing has a roller on a frame at the rear to create a uniform distance to the cyclist. Some riders objected when the UCI insisted on them in 1920. The pacer stands or sits upright to offer a maximum windbreak, and the handlebars are extended to facilitate the stance, in a standardized leather suit that allows for the same slipstream effect for any rider. Speeds of can be reached; the average is . The bicycles are steel, sturdy and have a smaller front wheel to let the stayer bend forward into  the slipstream. Pacing by Derny. A Derny is a light motorbike typically driven by a Zurcher two-stroke engine and by being pedaled through a fixed gear, typically of 70 teeth on the front chainring and 11 on the sprocket on the back wheel. The combination allows for smooth acceleration and slowing, important when the rider taking pace is centimetres from the pacer's shielded back wheel. A coupling between the motor and the back wheel ensures the machine will not stop dead if the motor seizes. The first Entraineur or Bordeaux–Paris models, with a petrol tank across the  handlebars, were built by Roger Derny et Fils of the avenue de St Mandé, Paris, France in 1938. That closed in 1957, though another company, Derny Service of rue de Picpus serviced and rebuilt machines into the 1970s. Derny also built a street adaptation called the Solo as well as tandems and mopeds. The name "derny" is now applied to all such vehicles, regardless of manufacturer. It is used by the Larousse dictionary as a generic term for a small pacing motorcycle used in cycle races. The machine has to be bump-started. It can then pace riders up to  , although races rarely exceed . Riders behind Derny-pacers ride conventional track bicycles. Bordeaux–Paris was paced by Dernys for part of its route from 1946 to 1985. Pacers. Cooperation between pacer and stayer includes the use of terms and signals understood internationally, because pacers and stayers may be of different nationalities. The stayer needs to be close to the roller to gain maximum profit from the slipstream; if he gets too close he may hit the roller and fall, if he falls too far behind it, he loses the slipstream effect and will quickly fall further back. The pacer then  has to slow down so he can catch up and then accelerate without again losing his rider. Races. Races are in velodromes or on other oval and steeply banked tracks to allow high-speed racing. After a flying start the cyclists link up with their pacers. Riding counterclockwise, passing can only be done on the right, a blue line separating the longer passing lane from the inner. Typically four to six couples compete in a race, covering up to or racing over a set time. Keirin. The keirin, a Japanese sprint with a paced start which has spread across the  world, is a variation of motor-paced racing. A group of cyclists use a single pacer to get to speed and then sprint to the finish on their own. Records. The first registered distance record behind pacers was by F. L. Dodds of Britain, who on a solid-tired bicycle rode close to in the grounds of Cambridge University in 1876. He was paced by relays of individual cyclists. A south London rider, J. W. Stocks, set an unbeaten British record of in an hour behind pacers on 27 September 1897. From 1893 to 1895, Hélène Dutrieu set several women 's paced hour records, ending with 39.190 km at Vélodrome Roubaisien. In 1896, Amélie le Gall set a new women's paced hour record of 43.461 at Vélodrome Buffalo. The first hour record behind a motorcycle was set at by Harry Elkes of the USA in 1898. He rode behind a motor-powered tandem. The first record behind a pure motorcycle was , by Tom Linton of Britain, at the Parc des Princes track in northwest Paris in 1902. The speed increased but records become more hazy because some were made under restrictions imposed by the Union Cycliste Internationale and others  with no rules at all. On 12 October 1950 Karl-Heinz Kramer set the world record for absolute speed behind a motorcycle with on the Grenzlandring. The Frenchman, José Meiffret, set a record behind a Mercedes-Benz 300 SL on the autobahn at Freiburg, Germany, on 16 July 1962. His bicycle had a 130-tooth chainring and wooden rims. Fred Rompelberg, using a dragster with a large shield as pacer, achieved on the Bonneville Salt Flats on 15 October 1995. The British absolute speed record is held by Neil Campbell who pedaling at a speed of on 25 April 2016  behind a modified VW Passat. He broke the previous record of set by Guy Martin in 2013 behind a modified racing truck. Denise Mueller-Korenek claimed a women's bicycle land speed record at at the Bonneville Salt Flats on 10 September 2016. Mueller was coached by former record holder John Howard. It is not clear which authority was supervising the record attempt. On 17 September 2018, again at Bonneville, she took the world record with a top speed of 183.93 mph (296 km/h) behind a converted rail dragster with a fairing.