Staying is cycling behind a pacer (bicycle, car and later motorcycle) the bicycle follows as closely as possible to be in the slipstream of the pacer. Following too closely is dangerous, staying too far behind eliminates the slipstream advantage. In Belgium-Flanders staying was usually called half fond or demi-fond rides like Bordeaux-Paris (600km race) were called course de fond in France. First this was ridden with pacers on tandem bikes, later behind cars and finally special motorcycles were built for this sport discipline. The first heavy stayer motorcycles were made just after World War I by Anzani after he put 2 cylinders of an airplane star engine on a crankcase to make a large 2000cc engine. The motorcycle had no gearbox and was driven by a 10 cm wide leather belt. The handlebars were extended so that the pacer, also called an entraineur could stand straight to make maximum slipstream, also called an abri. A roll bar was placed at the back of the motorcycle so that the cyclist could follow to within a few inches and not cause an accident should he hit the motorcycle. The throttle of the motorcycle had a special ratchet system so that throttle could be given and held evenly. These heavy motorcycles could accelerate from walking speed to more like 100 km/h without any problem. In 1925 came an improved engine block like this one with OHV operation and now 2400cc. In1938 these heavy engine blocks went out of production and no more heavy stayers were built. As a result, the stayers had to maintain and repair their own machine. When these were banned by the UCI in 1973 there were still 86 heavy stayers active.Gangmakers have also existed since 1938 (after heavy engine construction stopped) with a 98cc engine, this was called Derny after the maker Roger Derny in France. These were faded away in 2015 with electric-powered Derny's.

In 1924, Belgian Leon Vanderstruyft broke the world endurance record on the Monthléry bowl course in France. This record had stood since 1909 in the name of the Frenchman Guignard. The new record now stood at 115km/h, a shame for France thought Leon Lauthier. France was humiliated by a Belgian and even then on French territory. He immediately started building a stayer motorcycle and 3 months later it was ready, fully equipped with an aerodynamic aluminum cladding. The motorcycle was ready but then there was the next problem, finding someone crazy enough to dare to ride behind this projectile. That's how Lauthier got to national champion Jean Brunier, a professional road rider who only rode for the money. On November 1, 1925, it would happen and yes Léon Lauthier and Jean Brunier broke the world record and now set it at 120km/h.

Attached you can see a photo by Roger Violet where this motorcycle is riding together with a 2nd in 1947 with world champion Jean-Jacques Lamboley behind it.

This Stayer is of the brand Léon Lauthier and has frame number 25.

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