Derailleur gears battery pack and to a small electric motor that drives the derailleur. Although expensive, an electronic system could save a racing cyclist time when changing gears. Derailleur gears Derailleur gears are a variable-ratio transmission system commonly used on bicycles, consisting of a chain, multiple sprockets of different sizes, and a mechanism to move the chain from one sprocket to another. Although referred to as "gears" in the bike world, these bicycle "gears" are technically "sprockets" since they drive or are driven by a chain, and are not driven by one another. Modern front and rear derailleurs typically consist of a
Units of measurement in France before the French Revolution (league) had a number of variations, particularly the "aune" (which was used to measure cloth The "loi du 19 frimaire an VIII" (Law of 10 December 1799) states that one decimal metre is exactly 443.296 French lines, or "3 pieds 11.296 lignes de la "Toise du Pérou"". Thus the French royal foot is exactly 9000/27,706 metres (about 0.3248 m). In Quebec, the surveys in French units were converted using the relationship 1 "pied" (of the French variety, the same word being used for English feet as well) = 12.789 English inches. This makes the Quebec "pied" very slightly smaller (about