|
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] |
Shimano
, originally and later , is a Japanese multinational manufacturing company for cycling components, fishing tackles and rowing equipment, who also produced golf supplies until 2005 and snowboarding gear until 2008. Named after founder Shozaburo Shimano (, 1894–1958) and headquartered in Sakai, Osaka Prefecture, the company has 32 consolidated and 11 unconsolidated subsidiaries, with the primary manufacturing plants based in Kunshan (China), Malaysia and Singapore. In 2017, Shimano had net sales of US $3.2 billion, 38% in Europe, 35% in Asia, and 11% in North America. Bicycle components represented 80%, fishing tackle 19%, and other products 0.1%. The company is publicly traded, with 93 million shares of common stock outstanding. They are also the official neutral support for most of the UCI World Tour. Cycling Shimano sales constitute an estimated 70–80% of the global bicycle component market by value. Its products include drivetrain, brake, wheel and pedal components ... [...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] |
Birmingham Small Arms Company
The Birmingham Small Arms Company Limited (BSA) was a major British industrial combine, a group of businesses manufacturing military and sporting firearms; bicycles; motorcycles; cars; buses and bodies; steel; iron castings; hand tool, hand, power tool, power, and machine tool, machine tools; coal cleaning and handling plants; sintered metals; and hard chrome process. After the Second World War, BSA did not manage its business well, and a government-organised rescue operation in 1973 led to a takeover of such operations as it still owned. Those few that survived this process disappeared into the ownership of other businesses. History of the BSA industrial group Machine-made guns BSA began in June 1861 in the Gun Quarter, Birmingham, England. It was formed by a group of fourteen gunsmith members of the Birmingham Small Arms Trade Association specifically to manufacture guns by machinery. They were encouraged to do this by the War Office which gave the BSA gunsmiths free access ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nabe 01 KMJ
''Nabemono'' (鍋物, なべ物, ''nabe'' "cooking pot" + ''mono'' "thing"), or simply ''nabe'', is a variety of Japanese hot pot dishes, also known as one pot dishes and "things in a pot". Description Nabemono are stews and soups containing many types of ingredients that are served while still boiling. Because of that, Nabe is typically enjoyed in cold days or the winter. In modern Japan, nabemono are kept hot at the dining table by portable stoves. The dish is frequently cooked at the table, and the diners can pick the cooked ingredients they want from the pot. It is either eaten with the broth or with a dip. Further ingredients can also be successively added to the pot. There are two types of nabemono in Japan: lightly flavored stock (mostly with kombu) types such as ''yudōfu'' (湯豆腐) and ''mizutaki'' (水炊き), eaten with a dipping sauce ('' tare'') to enjoy the taste of the ingredients themselves; and strongly flavored stock, typically with miso, soy sauce, dashi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torque
In physics and mechanics, torque is the rotational equivalent of linear force. It is also referred to as the moment of force (also abbreviated to moment). It represents the capability of a force to produce change in the rotational motion of the body. The concept originated with the studies by Archimedes of the usage of levers, which is reflected in his famous quote: "''Give me a lever and a place to stand and I will move the Earth''". Just as a linear force is a push or a pull, a torque can be thought of as a twist to an object around a specific axis. Torque is defined as the product of the magnitude of the perpendicular component of the force and the distance of the line of action of a force from the point around which it is being determined. The law of conservation of energy can also be used to understand torque. The symbol for torque is typically \boldsymbol\tau, the lowercase Greek letter ''tau''. When being referred to as moment of force, it is commonly denoted by . In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
San Francisco, CA
San Francisco (; Spanish for " Saint Francis"), officially the City and County of San Francisco, is the commercial, financial, and cultural center of Northern California. The city proper is the fourth most populous in California and 17th most populous in the United States, with 815,201 residents as of 2021. It covers a land area of , at the end of the San Francisco Peninsula, making it the second most densely populated large U.S. city after New York City, and the fifth most densely populated U.S. county, behind only four of the five New York City boroughs. Among the 91 U.S. cities proper with over 250,000 residents, San Francisco was ranked first by per capita income (at $160,749) and sixth by aggregate income as of 2021. Colloquial nicknames for San Francisco include ''SF'', ''San Fran'', ''The '', ''Frisco'', and ''Baghdad by the Bay''. San Francisco and the surrounding San Francisco Bay Area are a global center of economic activity and the arts and sciences, spurred ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interference Fit
An interference fit, also known as a pressed fit or friction fit is a form of fastening between two ''tight'' fitting mating parts that produces a joint which is held together by friction after the parts are pushed together. Depending on the amount of interference, parts may be joined using a tap from a hammer or ''pressed'' together using a hydraulic ram. Critical components that must not sustain damage during joining may also be cooled significantly below room temperature to shrink one of the components before fitting. This method allows the components to be joined without force and producing a shrink fit interference when the component returns to normal temperature. Interference fits are commonly used with aircraft fasteners to improve the fatigue life of a joint. Introducing interference between parts These fits, though applicable to shaft and hole assembly, are more often used for bearing-housing or bearing-shaft assembly. Tightness of fit The tightness of fit is con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ratchet (device)
A ratchet (occasionally spelled rachet) is a mechanical device that allows continuous linear or rotary motion in only one direction while preventing motion in the opposite direction. Ratchets are widely used in machinery and tools. The word ''ratchet'' is also used informally to refer to a ratcheting socket wrench. __TOC__ Theory of operation A ratchet consists of a round gear or a linear rack with teeth, and a pivoting, spring-loaded finger called a '' pawl'' (or ''click'', in clocks and watches) that engages the teeth. The teeth are uniform but are usually asymmetrical, with each tooth having a moderate slope on one edge and a much steeper slope on the other edge. When the teeth are moving in the unrestricted (i.e. forward) direction, the pawl easily slides up and over the gently sloped edges of the teeth, with a spring forcing it (often with an audible 'click') into the depression between the teeth as it passes the tip of each tooth. When the teeth move in the opposite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bending Moment
In solid mechanics, a bending moment is the reaction induced in a structural element when an external force or moment is applied to the element, causing the element to bend. The most common or simplest structural element subjected to bending moments is the beam. The diagram shows a beam which is simply supported (free to rotate and therefore lacking bending moments) at both ends; the ends can only react to the shear loads. Other beams can have both ends fixed (known as encastre beam); therefore each end support has both bending moments and shear reaction loads. Beams can also have one end fixed and one end simply supported. The simplest type of beam is the cantilever, which is fixed at one end and is free at the other end (neither simple or fixed). In reality, beam supports are usually neither absolutely fixed nor absolutely rotating freely. The internal reaction loads in a cross-section of the structural element can be resolved into a resultant force and a resultant couple. F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dropout (bicycle Part)
A fork end, fork-end, or forkend is a slot in a bicycle frame or bicycle fork where the axle of a bicycle wheel is attached. A dropout is a type of fork end that allows the rear wheel to be removed without first derailing the chain. Track bicycle frames have track fork ends, on which the opening faces rearwards. Because they do not have dropouts, the chain must be derailed from the sprocket before the rear wheel can be removed from a typical track bike. Some single-speed bicycles intended for street or trail use are also equipped with track fork ends instead of dropouts. On bicycles that do not have a derailleur or other chain tensioning device, rear ''horizontal dropouts'' allow adjustment of chain tension, and can accommodate a range of chain lengths or cog sizes. They were standard on most older derailleur bicycles from before the 1990s. An older derailleur-equipped bicycle with horizontal dropouts can be readily converted into singlespeed, fixed gear or to use an internally ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hex Key
Hex keys of various sizes Socket head screws of various sizes A hex key (also, hex wrench, Allen key and Allen wrench) is a simple driver for bolts or screws that have heads with ''internal'' hexagonal recesses (sockets). Hex keys are formed from a single piece of hard hexagonal steel rod, having blunt ends that fit snugly into similarly-shaped screw sockets. The rods are bent to 90º, forming two arms of unequal length resembling an "L". The tool is usually held and twisted by its long arm, creating a relatively large torque at the tip of the short arm; it can also be held by its short arm to access screws in difficult-to-reach locations and to turn screws faster at the expense of torque. Hex keys are designated with a socket size and are manufactured with tight tolerances. As such, they are commonly sold in kits that include a variety of sizes. Key length typically increases with size, but not necessarily proportionally so. Variants on this design have the short end inse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bicycle Pedal
The pedal is the part of a bicycle that the rider pushes with their foot to propel the vehicle. It provides the connection between the cyclist's foot or shoe and the crank allowing the leg to turn the bottom bracket spindle and propel the bicycle's wheels. A pedal usually consists of a spindle that threads into the end of the crank, and a body on which the foot rest is attached, that is free to rotate on bearings with respect to the spindle. Pedals were initially attached to cranks connecting directly to the driven (usually front) wheel. The safety bicycle, as it is known today, came into being when the pedals were attached to a crank driving a sprocket that transmitted power to the driven wheel by means of a roller chain. Types Just as bicycles come in many varieties, there are different types of pedals to support different types of cycling. Flat and platform Traditionally, platform pedals were pedals with a relatively large flat area for the foot to rest on, in contrast t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Shimano"){kind=spacer}
