Classification | Bicycle tools |
---|
A chain tool is a small mechanical device used to "break" a bicycle chain in such a way that it can be mended with the same tool. A bicycle chain has links and plates that are pinned together; these pins can be pushed out with the chain tool. Because the pins are pushed out gradually with a screw, they can be partially removed or fully removed, depending upon the intention of the user.
The chain tool has two positions where a chain can be inserted perpendicular to the tool, one close to the movable screw portion, and one lower down just above the fixed end. In each position, there are a pair of protruding tabs; one fits into the center of one link of the chain, the other fits into the center of the next link. With the chain properly in place, the pin is held in the center of the tool, so that the tip of the movable screw can press on the end of the pin. The end of the screw is slightly narrower than the pin, so that it can press the pin through the link. Often the end of the screw is a removable piece which can be replaced when worn.
Most chain tools are designed for chains where the links have flat plates. For chains with complicated shaped plates designed to facilitate smooth shifting, specific chain tools are available which are identical in design and operation, but have the ears protruding into the chain shaped in cross section to fit the links of the particular chain in question precisely, so as to hold the pin in the all-important vertical alignment with the screw of the tool.
Some chain tools are better at removing pins than they are at inserting them. Once completely removed, chain pins are often very difficult to insert with a tool unless it has been specifically designed to do so. Users may overcome this limitation of some tools by never completely removing a pin that they intend to replace. They push the pin so that the chain can be broken, to shorten it for example, but so that it is firmly retained in the farthest plate. This way, even simple chain tools can press the pin back into place.
While a chain tool is required to shorten simple chains on a bicycle, and as described above, can often be used to reconnect them, there are fast-release chain links that allow repeated making and breaking of a chain. They are connected by hand pressure but often need a pair of needle-nosed pliers for removal. These links invariably replace a pair of outside plates on a chain, so joining two sets of inside plates. Bicycles with a single front chainring and rear sprocket (for example bicycles with hub gears or coaster brake hubs) may have a master link on the chain which holds the pin in place with an easily removable c-clip. Some master links are bevelled on top, and can interfere with the smooth operation of a derailleur system. Some derailleur suppliers have produced a chain with a fast-release link, made with straight plates to suit their derailleur products.
A chain tool is usually needed to shorten a chain, even when a fast-release link is being used, unless the combined number of links plus the connection link just happens to be the length required. Consider the following example.
Assume that an old derailleur chain is to be replaced with a new chain containing a suitable fast release link, supplied with it. The old chain is broken with a chain tool to remove it, and counting the links it is noted that there were 112 in total. The new chain should have the same length, but counting its links concludes that including the fast-release link there are 116 of them. (The chain link count on a new chain will not necessarily agree with the number given on its packaging.) A chain of this type is provided with inner plates at both ends for this purpose. Bearing in mind that the chain must end up with two sets of inner plate ends after the shortening, then the chain tool can be used to completely remove four links. The fast-release link plates are installed by hand as if they were a set of outer plates, and can be fixed in place by hand pressure alone. There are variations of the method in use, but in each case a chain tool will usually be needed.
Components of an electrical circuit are electrically connected if an electric current can run between them through an electrical conductor. An electrical connector is an electromechanical device used to create an electrical connection between parts of an electrical circuit, or between different electrical circuits, thereby joining them into a larger circuit.
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.
The crankset or chainset is the component of a bicycle drivetrain that converts the reciprocating motion of the rider's legs into rotational motion used to drive the chain or belt, which in turn drives the rear wheel. It consists of one or more sprockets, also called chainrings or chainwheels attached to the cranks, arms, or crankarms to which the pedals attach. It is connected to the rider by the pedals, to the bicycle frame by the bottom bracket, and to the rear sprocket, cassette or freewheel via the chain.
A bicycle chain is a roller chain that transfers power from the pedals to the drive-wheel of a bicycle, thus propelling it. Most bicycle chains are made from plain carbon or alloy steel, but some are nickel-plated to prevent rust, or simply for aesthetics.
The bottom bracket on a bicycle connects the crankset (chainset) to the bicycle and allows the crankset to rotate freely. It contains a spindle to which the crankset attaches, and the bearings that allow the spindle and crankset to rotate. The chainrings and pedals attach to the cranks. Bottom bracket bearings fit inside the bottom bracket shell, which connects the seat tube, down tube and chain stays as part of the bicycle frame.
Torx is a trademark for a type of screw drive characterized by a 6-point star-shaped pattern, developed in 1967 by Camcar Textron. A popular generic name for the drive is star, as in star screwdriver or star bits. The official generic name, standardized by the International Organization for Standardization as ISO 10664, is hexalobular internal. This is sometimes abbreviated in databases and catalogs as 6lobe. Torx Plus,Torx Paralobe and Torx ttap are improved head profiles.
Roller chain or bush roller chain is the type of chain drive most commonly used for transmission of mechanical power on many kinds of domestic, industrial and agricultural machinery, including conveyors, wire- and tube-drawing machines, printing presses, cars, motorcycles, and bicycles. It consists of a series of short cylindrical rollers held together by side links. It is driven by a toothed wheel called a sprocket. It is a simple, reliable, and efficient means of power transmission.
A single-speed bicycle is a type of bicycle with a single gear ratio. These bicycles are without derailleur gears, hub gearing or other methods for varying the gear ratio of the bicycle.
A coupling or coupler is a mechanism, typically located at each end of a rail vehicle, that connects them together to form a train. The equipment that connects the couplers to the vehicles is the draft gear or draw gear, which must absorb the stresses of the coupling and the acceleration of the train.
The term bicycle tools usually refers to specialty tools only used on bicycles, as opposed to general purpose mechanical tools such as spanners and hex wrenches. Various bicycle tools have evolved over the years into specialized tools for working on a bicycle. Modern bicycle shops will stock a large number of tools for working on different bicycle parts. This work can be performed by a trained bicycle mechanic, or for simple tasks, by the bicycle owner.
A chuck is a specialized type of clamp used to hold an object with radial symmetry, especially a cylinder. In a drill, a mill and a transmission, a chuck holds the rotating tool; in a lathe, it holds the rotating workpiece.
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.
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.
The Club is the trademark version of a popular automotive steering-wheel lock, produced by Sharon, Pennsylvania-based Winner International. The company was formed in 1986 for the purpose of marketing the device. The inventor, James E. Winner Jr., derived the idea for the device from his service in the Korean War, where he and his fellow soldiers were instructed to secure the steering wheels of their vehicles with metal chains.
A freehub is a type of bicycle hub that incorporates a ratcheting mechanism.
A screw terminal is a type of electrical connection where a wire is held by the tightening of a screw.
The saw chain, or cutting chain, is a key component of a chainsaw. It consists of steel links held together by rivets, and superficially resembles the bicycle-style roller chain, although it is closer in design to a leaf chain. Its key differences are sharp cutting teeth on the outside of the chain loop, and flat drive links on the inside, to retain the chain on the saw's bar and allow propulsion by the engine or motor.
A quick release skewer is a mechanism for attaching a wheel to a bicycle. It consists of a rod threaded on one end and with a lever operated cam assembly on the other. The rod is inserted into the hollow axle of the wheel, a special nut is threaded on, and the lever is closed to tighten the cam and secure the wheel to the fork. Wheels equipped with quick release mechanisms can be removed from the bicycle frame and replaced without using tools by opening and closing the cam lever, thus more quickly than wheels with solid axles and nuts. On the negative side, a quick-release hub renders a wheel more vulnerable to theft and care must be taken to ensure that the mechanism is properly tightened.
A master link or quick-release link is a roller chain accessory that allows convenient connection and disconnection of a chain without the need for a chain tool. It acts as a set of the chain's outer plates, so joining two sets of the chain's inner plate ends. Such master links may or may not be re-usable. A chain tool is nonetheless needed to adjust a chain's length, for example to shorten a new chain before connecting its ends. They are used on bicycles and motorcycles.