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Wheelbuilding is the process of assembling wire wheels (generally a bicycle wheel, but including wheelchairs, and some cars). The components of a wire wheel are the rim, spokes, nipples, and hub.
The wheelwright must ensure that the wheel is true in two ways: lateral (sideways wobble) and radial (roundness/hop). The wheel also needs to be properly dished if applicable (the left and right sides of the rear wheel differ, the drive-side spokes requiring higher tension). Spokes should have no residual twist (windup) from tightening the nipples. The spokes may be "stress relieved", i.e. subjected to a greater tension during building than they are ever likely to encounter in use - usually by squeezing pairs of spokes together very hard. This 'yields' the spokes (and/or the hub) into a permanent shape where they bend around the hub flanges and each other.
Spoking patterns may be radial or semi-tangential. For a normal wheel size and spoke count, only the latter is suitable for a wheel that has to transmit torque from the hub to the rim, as with rear wheels or hub brakes. This rule is occasionally broken where a very large number of spokes is used or the wheel is unusually small in diameter, either of which reduces the amount of increased tensile stress on each radial spoke to an acceptable degree; some BMX bicycles and low-riders use radial spoking for both wheels. Rear wheels may also incorporate radial spoking on the non-drive side and semi-tangential spoking on the drive side. At least one example, the Mavic Ksyrium, has radial spoking on the drive side of the rear wheel.
The most common spoking pattern is "three-cross" where each spoke crosses three others on the same flange of the hub before meeting the rim. The last cross is normally "interlaced" by wrapping the spoke around the one from the other side of the flange. Radial-spoked wheels, where the spokes do not cross each other, saves roughly the weight of two spokes (because the spokes are shorter) compared to a three-cross wheel but run an increased risk of cracking at the hub flange, unless the hub is specifically designed for this pattern. Two-cross is sometimes used for hubs with large-diameter flanges (such as generator/dynamo hubs or large flange hubs), as it gives a more perpendicular spoke/rim angle, and four-cross is standard for spoke counts of 40 and above.
Most conventional bicycle wheels now use 32 or 36 spokes front and rear, although the asymmetry of the rear wheel (to allow for the cluster of sprockets), and the additional weight it carries, means it benefits from having more spokes than the front. Commonly used models vary from 18 spokes for racing bikes to 36 for cross-country touring bikes to 48 spokes on tandems and heavily abused BMX bikes. The minimum number of spokes allowed for competition is 12. [1] Some lowrider bicycles use as many as 144 brightly chromed spokes per wheel, although these are not meant for serious riding.
Wheels can be built by machine instead of by hand. However, machine-built wheels are rarely as satisfactory as handbuilt wheels, partly because it is uneconomical to allow the machine to spend long enough on each wheel for a perfect result but also because most machines leave spokes with some residual twist. Machine-built wheels can be identified by their lacing pattern (if it is not radial), as the spokes are laced the same on each side, rather than mirrored as on hand-built wheels.[ citation needed ] More modern "factory built" wheels such as Mavic's Ksyrium series are of quite different construction from that of a conventional wheel, trading a deeper and stronger rim for fewer spokes. They are popular, and quite light (in the more expensive models) but not as durable, readily repairable or maintainable as a conventional wheel.
Stainless steel is the most common material for spokes, although most mass-produced budget wheels use galvanized steel spokes. Other materials such as titanium or aluminum are often used to reduce weight. Some wheels are designed around carbon fiber spokes, which are often completely integrated with the hub and rim and bladed in shape. Non-steel spokes are normally reserved for racing bikes and other specialist applications where weight, aerodynamics and performance are valued over durability and cost.
Rims were traditionally made of steel but currently aluminum is by far most common and best choice due to its light weight, high durability and stiffness. Wood is also used. Composite materials such as carbon fiber are sometimes used, typically for racing competitions such as time trial, triathlon and track cycling, although carbon fiber is becoming more common for recreational uses such as road cycling or mountain biking due to its looks, strength and feel.
Motorcycle wire wheels typically use 36 or 40 spokes, of much heavier gauge than those on a bicycle. They are never "interlaced" in the manner described above, nor are "radial" builds recommended (only wheels without brakes). Motorcycle rims are dimpled toward the hub at each spoke location, and the holes for the spokes are drilled into the dimples at an angle. This angle is a function of the cross-pattern used to lace the wheel, the diameter of the hub flanges, and the width of the hub at the flanges. Conical-hub wheels have a different angle drilled into one side of the rim when compared with the other side. Adequate spoke tension is very important with motorcycle wheels, because of the greater torque applied to the wheel by an engine or disc brake. Loose spokes on a wheel fatigue rapidly and break, usually at the bend where they attach to the hub. When this happens, the wheel must be rebuilt using all new spokes, because even unbroken spokes in such a wheel are fatigued, and will usually break when tightened during the truing operation.
The correct length of spokes required can be calculated using rim diameter, hub flange diameter, hub width, lacing pattern, and number of spokes. See [2] and. [3] [ self-published source ] These calculations can be done either by hand (the old-fashioned way - with a pen, paper and calculator) or by using a computer. There are many programs available and they range in complexity from simple Excel spreadsheets to stand alone desktop applications and web based calculators. An alternative method is to refer to a table which has the spoke lengths for a number of common hub and rim combinations.
A good wheelbuilder will ensure that the valve hole lies between two nearly parallel spokes to ease attachment of a pump head. This does not affect the structural integrity of the wheel, and this rule is usually observed.
If the hub has a maker's label on its barrel, it is convention for the label to face (and be readable through) the valve hole.[ citation needed ] The rim labels should be readable from the right-hand side (drive side) of the bicycle. The hub labels should face in the same direction front and rear (generally so they are readable from the seat), this means that even an undished, symmetrical front wheel has to be laced to the rim the "proper" way round, if perfection is the aim.
A tandem bicycle or twin is a form of bicycle designed to be ridden by more than one person. The term tandem refers to the seating arrangement, not the number of riders. Patents related to tandem bicycles date from the mid 1880s. Tandems can reach higher speeds than the same riders on single bicycles, and tandem bicycle racing exists. As with bicycles for single riders, there are many variations that have been developed over the years.
A mountain bike (MTB) or mountain bicycle is a bicycle designed for off-road cycling. Mountain bikes share some similarities with other bicycles, but incorporate features designed to enhance durability and performance in rough terrain, which makes them heavier, more complex and less efficient on smooth surfaces. These typically include a suspension fork, large knobby tires, more durable wheels, more powerful brakes, straight, extra wide handlebars to improve balance and comfort over rough terrain, and wide-ratio gearing optimised for topography and application. Rear suspension is ubiquitous in heavier-duty bikes and now common even in lighter bikes. Dropper posts can be installed to allow the rider to quickly adjust the seat height.
An axle or axletree is a central shaft for a rotating wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to the vehicle, with the wheels rotating around the axle. In the former case, bearings or bushings are provided at the mounting points where the axle is supported. In the latter case, a bearing or bushing sits inside a central hole in the wheel to allow the wheel or gear to rotate around the axle. Sometimes, especially on bicycles, the latter type axle is referred to as a spindle.
A spoke is one of some number of rods radiating from the center of a wheel, connecting the hub with the round traction surface.
A bicycle brake reduces the speed of a bicycle or prevents it from moving. The three main types are: rim brakes, disc brakes, and drum brakes.
A spoke wrench or spoke key is a small wrench or tool used to adjust the tension in the spokes of a tension-spoked wheel. A spoke wrench is sometimes called a nipple wrench, as it is the spoke nipple – not the spoke – that is turned in the process of changing the tension of a spoke.
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.
A touring bicycle is a bicycle designed or modified to handle bicycle touring. To make the bikes sufficiently robust, comfortable and capable of carrying heavy loads, special features may include a long wheelbase, frame materials that favor flexibility over rigidity, heavy duty wheels, and multiple mounting points.
A racing bicycle, also known as a road bike is a bicycle designed for competitive road cycling, a sport governed by and according to the rules of the Union Cycliste Internationale (UCI).
29ers or two-niners are mountain bikes and hybrid bikes that are built to use 700c or 622 mm ISO wheels, commonly called 29" wheels. Most mountain bikes once used ISO 559 mm wheels, commonly called 26" wheels. The ISO 622 mm wheel is typically also used for road-racing, trekking, cyclo-cross, touring and hybrid bicycles. In some countries, mainly in Continental Europe, ISO 622 mm wheels are commonly called 28" wheels or "28 Incher".
Zipp is an American company that is best known for designing, manufacturing, and marketing carbon-composite bicycle wheels for road cycling, triathlons, track racing, and mountain biking. The company's product range also includes handlebars, stems, seat posts, tires, inner tubes, handlebar tape, and bags.
The rim is the "outer edge of a wheel, holding the tire". It makes up the outer circular design of the wheel on which the inside edge of the tire is mounted on vehicles such as automobiles. For example, on a bicycle wheel the rim is a large hoop attached to the outer ends of the spokes of the wheel that holds the tire and tube. In cross-section, the rim is deep in the center and shallow at the outer edges, thus forming a "U" shape that supports the bead of the tire casing.
A wheel truing stand is a specialized tool for "truing" (straightening) bicycle wheels. Individual models differ slightly, but all consist of an axle stand on which the wheel can rotate and calipers, to measure slight deviations of the wheel's rim from ideal alignment. Proper wheel alignment includes lateral, radial and dish/centering trues which keep the wheel straight and strong. The stand is used in conjunction with an appropriately sized spoke wrench to loosen or tighten the spokes that connect the wheel's hub to the rim.
Wire wheels, wire-spoked wheels, tension-spoked wheels, or "suspension" wheels are wheels whose rims connect to their hubs by wire spokes. Although these wires are generally stiffer than a typical wire rope, they function mechanically the same as tensioned flexible wires, keeping the rim true while supporting applied loads. The term suspension wheel should not be confused with vehicle suspension.
A centreless wheel is a wheel where the force is delivered in the perimeter of the wheel rather than in the centre; there are a variety of centreless wheels with their own characteristics including the hubless wheel, spokeless wheel, orbital wheel and rim-rider.
A bicycle tire is a tire that fits on the wheel of a bicycle or similar vehicle. These tires may also be used on tricycles, wheelchairs, and handcycles, frequently for racing. Bicycle tires provide an important source of suspension, generate the lateral forces necessary for balancing and turning, and generate the longitudinal forces necessary for propulsion and braking. Although the use of a pneumatic tire greatly reduces rolling resistance compared to the use of a rigid wheel or solid tire, the tires are still typically, the second largest source, after wind resistance, of power consumption on a level road. The modern detachable pneumatic bicycle tire contributed to the popularity and eventual dominance of the safety bicycle.
Motorcycle tyres are the outer part of motorcycle wheels, attached to the rims, providing traction, resisting wear, absorbing surface irregularities, and allowing the motorcycle to turn via countersteering. The two tyres' contact patches are the motorcycle's connection to the ground, and so are fundamental to the motorcycle's suspension behaviour, and critically affect safety, braking, fuel economy, noise, and rider comfort.
Mountain bike trials, also known as observed trials, is a discipline of mountain biking in which the rider attempts to pass through an obstacle course without setting foot to ground. Derived from motorcycle trials, it originated in Catalonia, Spain as trialsín and is said to have been invented by Pere Pi, the father of Ot Pi, a world champion motorcycle trials rider. Pi's father had wanted his son to learn motorcycle trials by practicing on an ordinary bicycle.