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Cogset
On a bicycle, the cassette or cluster is the set of multiple sprockets that attaches to the hub on the rear wheel. A cogset works with a rear derailleur to provide multiple gear ratios to the rider. Cassettes come in two varieties, freewheels or cassettes, of which cassettes are a newer development. Although cassettes and freewheels perform the same function and look almost the same when installed, they have important mechanical differences and are not interchangeable. Freewheels A freewheel (also known as a block) consists of either a single sprocket or a set of sprockets mounted on a body which contains an internal ratcheting mechanism and mounts on a threaded hub. Threaded rear hubs were available in different thread patterns depending on the country of manufacture, French and British threads being the most common. British C.E.I. (Cycle Engineers Institute) thread was adopted as the international standard and is now known as B.S.C. (British Standard Cycle). It is a standar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freehub
A freehub is a type of bicycle hub that incorporates a ratcheting mechanism. A set of sprockets (called a "cassette") is mounted onto a splined shaft of the freehub to engage the chain. The ratcheting mechanism is a part of the hub, in contrast to a freewheel, an older technology, which contains both the sprockets and a ratcheting mechanism in a single unit separate from the hub. In many high-end and midrange bicycles, freehubs have replaced freewheel systems. A freewheel mechanism allows a rider to stop pedalling whilst the cycle is still in forward motion. On a cycle without a freewheel mechanism, the rider has to keep pedalling whenever the cycle is moving. Comparison to freewheels The freehub concept answers several drawbacks encountered with the freewheel design: * Freewheels are threaded onto an axle hub, using conventional right-hand threads. As the bicycle rider pedals, the freewheel is continuously kept tight, as chain torque is in the right-hand direction. This be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freewheel
Freewheel mechanism In mechanical or automotive engineering, a freewheel or overrunning clutch is a device in a transmission that disengages the driveshaft from the driven shaft when the driven shaft rotates faster than the driveshaft. An overdrive is sometimes mistakenly called a freewheel, but is otherwise unrelated. The condition of a driven shaft spinning faster than its driveshaft exists in most bicycles when the rider stops pedaling. In a fixed-gear bicycle, without a freewheel, the rear wheel drives the pedals around. An analogous condition exists in an automobile with a manual transmission going downhill, or any situation where the driver takes their foot off the gas pedal, closing the throttle: the wheels drive the engine, possibly at a higher RPM. In a two-stroke engine, this can be catastrophic—as many two stroke engines depend on a fuel/oil mixture for lubrication, a shortage of fuel to the engine starves oil from the cylinders, and the pistons can soon seize, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bicycle Wheel
A bicycle wheel is a wheel, most commonly a wire wheel, designed for a bicycle. A pair is often called a wheelset, especially in the context of ready built "off the shelf" performance-oriented wheels. Bicycle wheels are typically designed to fit into the bicycle frame, frame and bicycle fork, fork via Dropout (bicycle part), dropouts, and hold bicycle tires. Invention The first wheel to use the tension in wire wheel, metal spokes was invented by George Cayley, Sir George Cayley to achieve lightness in his 1853 glider. Construction The first bicycle wheels followed the traditions of carriage building: a wooden hub, a fixed steel axle (the bearings were located in the fork ends), wooden spokes and a shrink fitted iron tire. A typical modern wheel has a metal hub, wire tension spokes and a metal or carbon fiber rim which holds a pneumatic rubber tire. Hub A hub is the center part of a bicycle wheel. It consists of an axle, bearing (mechanical), bearings and a hub shell. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Derailleur Gears
Shimano 600 front derailleur (1980) A derailleur is a variable-ratio bicycle gearing system consisting of a chain, multiple sprockets of different sizes, and a mechanism to move the chain from one sprocket to another. Modern front and rear derailleurs typically consist of a moveable chain-guide that is operated remotely by a Bowden cable attached to a shifter mounted on the down tube, handlebar stem, or handlebar. When a rider operates the lever while pedalling, the change in cable tension moves the chain-guide from side to side, "derailing" the chain onto different sprockets. Etymology ''Dérailleur'' is a French word, derived from the derailment of a train from its tracks. Its first recorded use was 1930. History A modern road bicycle drivetrain with front and rear derailleurs Various derailleur systems were designed and built in the late 19th century. One example is the Protean two-speed derailleur available on the Whippet safety bicycle. The French bicycle to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bicycle
A bicycle, also called a pedal cycle, bike or cycle, is a human-powered or motor-powered assisted, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A is called a cyclist, or bicyclist. Bicycles were introduced in the 19th century in Europe. By the early 21st century, more than 1 billion were in existence. These numbers far exceed the number of cars, both in total and ranked by the number of individual models produced. They are the principal means of transportation in many regions. They also provide a popular form of recreation, and have been adapted for use as children's toys, general fitness, military and police applications, courier services, bicycle racing, and bicycle stunts. The basic shape and configuration of a typical upright or "safety bicycle", has changed little since the first chain-driven model was developed around 1885. However, many details have been improved, especially since the advent of modern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bicycle Gearing
Bicycle gearing is the aspect of a bicycle drivetrain that determines the relation between the cadence, the rate at which the rider pedals, and the rate at which the drive wheel turns. On some bicycles there is only one gear and, therefore, the gear ratio is fixed, but most modern bicycles have multiple gears and thus multiple gear ratios. A shifting mechanism allows selection of the appropriate gear ratio for efficiency or comfort under the prevailing circumstances: for example, it may be comfortable to use a high gear when cycling downhill, a medium gear when cycling on a flat road, and a low gear when cycling uphill. Different gear ratios and gear ranges are appropriate for different people and styles of cycling. A cyclist's legs produce power optimally within a narrow pedalling speed range, or cadence. Gearing can be optimized to use this narrow range as efficiently as possible. As in other types of transmissions, the gear ratio is closely related to the mechanical ad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sprocket
A sprocket, sprocket-wheel or chainwheel is a profiled wheel with teeth that mesh with a chain, track or other perforated or indented material. The name 'sprocket' applies generally to any wheel upon which radial projections engage a chain passing over it. It is distinguished from a gear in that sprockets are never meshed together directly, and differs from a pulley in that sprockets have teeth and pulleys are smooth except for timing pulleys used with toothed belts. Sprockets are used in bicycles, motorcycles, tracked vehicles, and other machinery either to transmit rotary motion between two shafts where gears are unsuitable or to impart linear motion to a track, tape etc. Perhaps the most common form of sprocket may be found in the bicycle, in which the pedal shaft carries a large sprocket-wheel, which drives a chain, which, in turn, drives a small sprocket on the axle of the rear wheel. Early automobiles were also largely driven by sprocket and chain mechanism, a practice la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bicycle Wheel
A bicycle wheel is a wheel, most commonly a wire wheel, designed for a bicycle. A pair is often called a wheelset, especially in the context of ready built "off the shelf" performance-oriented wheels. Bicycle wheels are typically designed to fit into the bicycle frame, frame and bicycle fork, fork via Dropout (bicycle part), dropouts, and hold bicycle tires. Invention The first wheel to use the tension in wire wheel, metal spokes was invented by George Cayley, Sir George Cayley to achieve lightness in his 1853 glider. Construction The first bicycle wheels followed the traditions of carriage building: a wooden hub, a fixed steel axle (the bearings were located in the fork ends), wooden spokes and a shrink fitted iron tire. A typical modern wheel has a metal hub, wire tension spokes and a metal or carbon fiber rim which holds a pneumatic rubber tire. Hub A hub is the center part of a bicycle wheel. It consists of an axle, bearing (mechanical), bearings and a hub shell. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Derailleur
Shimano 600 front derailleur (1980) A derailleur is a variable-ratio bicycle gearing system consisting of a chain, multiple sprockets of different sizes, and a mechanism to move the chain from one sprocket to another. Modern front and rear derailleurs typically consist of a moveable chain-guide that is operated remotely by a Bowden cable attached to a shifter mounted on the down tube, handlebar stem, or handlebar. When a rider operates the lever while pedalling, the change in cable tension moves the chain-guide from side to side, "derailing" the chain onto different sprockets. Etymology ''Dérailleur'' is a French word, derived from the derailment of a train from its tracks. Its first recorded use was 1930. History A modern road bicycle drivetrain with front and rear derailleurs Various derailleur systems were designed and built in the late 19th century. One example is the Protean two-speed derailleur available on the Whippet safety bicycle. The French bicycle tou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing military alliances: the Allies and the Axis powers. World War II was a total war that directly involved more than 100 million personnel from more than 30 countries. The major participants in the war threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. Aircraft played a major role in the conflict, enabling the strategic bombing of population centres and deploying the only two nuclear weapons ever used in war. World War II was by far the deadliest conflict in human history; it resulted in 70 to 85 million fatalities, mostly among civilians. Tens of millions died due to genocides (including the Holocaust), starvation, ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SRAM (bicycles)
SRAM LLC is a privately owned bicycle component manufacturer based in Chicago, Illinois, United States, founded in 1987. SRAM is an acronym comprising the names of its founders, Scott, Ray, and Sam, (where Ray is the middle name of the company's first CEO, Stan Day). The company is known for producing cycling components, including some internally developed, such as Grip Shift, EAGLE (1x12), DoubleTap, dedicated 1x11 mountain and their range of AXS drivetrains. The company grew organically and through acquisitions to become a cycling component brand, selling under the brands SRAM, Avid, RockShox, Truvativ, Quarq, Zipp, TIME Sport pedals, Hammerhead cycling computers, and Velocio cycling apparel. Their components are manufactured primarily in-house, in factories located in Portugal, Taiwan, China, and the U.S., and distributed and sold as Original equipment manufacturer (OEM) equipment and aftermarket components in markets globally. History As a start-up company, SRAM introduced t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperglide
Hyperglide is the name given by cycling component manufacturer Shimano to a sprocket design in their bicycle derailleur tooth cassette systems. It varies gear tooth profiles, and/or pins along the faces of freewheel (bicycle part), freewheel or cassette (bicycle part), cassette sprockets, or between the chainrings in a crankset, to ease shifting between them. Development The design, developed by Shimano, improves on their earlier Uniglide design (which used beveled/twisted gear teeth instead of ramps), and was introduced as part of a commercially viable shifter (bicycle part)#Index shifting, index shifting system. The Hyperglide ramps, along with laterally floating derailleur Jockey_wheel_(bicycle), jockey wheels, allows for enough "slop" in the system to make indexed shifting reliable, despite variations in shift cable adjustment and manufacturing or assembly tolerances. A Hyperglide freewheel or cassette on a bike with shifter (bicycle part)#Friction gear changing, friction ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
