The head tube is the part of a cycle's tubular frame within which the front fork steerer tube is mounted. [1] On a motorcycle, the "head tube" is normally called the steering head. On bicycles the manufacturer's brand located on the head tube is known as a head badge.
The head tube holds the bearings which allow the front fork steerer tube to pivot freely.
The steering axis angle, also called caster angle, is the angle that the head tube and hence the steering axis makes with the horizontal or vertical, depending on convention. The steering axis is the axis about which the steering mechanism (fork, handlebars, front wheel, etc.) pivots.
Head tubes can use one of several size standards
The head tube of a bicycle is sometimes designated by the fork steerer column it accepts. This can lead to confusion, since head tube inside diameters are dependent on the headset standard. For example, frames that take 25.4 mm (1 in) steerer columns can have three different inside diameters for threaded and threadless headsets (not including integrated-type headsets). The wide variety of integrated and non-standard, proprietary headsets that some frame manufacturers have created (and abandoned in some cases) makes listing all current and past head tube dimensions problematic. The following table includes the most common sizes; nominal head tube diameters are assuming a 0.1-0.2 mm interference fit, which is what most head tube reaming cutters are designed to bore. Adequate press fits are typically between 0.1 and 0.25 mm of interference.
| Steerer column nominal OD | Headset standard | Head tube nominal ID |
|---|---|---|
| 25.4 mm (1″) | 1″ JIS | 28.8 mm |
| 1″ ISO | 30.0 mm | |
| 1″ BMX/OPC | 32.5 mm | |
| 28.6 mm (11⁄8″) | 11⁄8″ standard, threaded and threadless | 33.8 mm |
| IS 11⁄8″ integrated 45°×36° | 41.1 mm | |
| Campagnolo "Hiddenset" 45°×45° | 41.9 mm | |
| Zero Stack/ Internal | 43.9 mm | |
| 31.75 mm (11⁄4″) | 11⁄4″ standard | 36.8 mm |
| 38.1 mm (1.5″) | 38.1 mm standard | 49.6 mm |
Standard motorcycle head tubes and headsets are sized for a 25.4 mm (1 in) diameter fork steerer tube.
A bicycle frame is the main component of a bicycle, onto which wheels and other components are fitted. The modern and most common frame design for an upright bicycle is based on the safety bicycle, and consists of two triangles: a main triangle and a paired rear triangle. This is known as the diamond frame. Frames are required to be strong, stiff and light, which they do by combining different materials and shapes.
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.
The Cannondale Bicycle Corporation is an American division of Dutch conglomerate Pon Holdings that supplies bicycles. Its headquarters are in Wilton, Connecticut, with engineering offices in Freiburg, Germany. Frames are manufactured in Taiwan.
A caster is an undriven wheel that is designed to be attached to the bottom of a larger object to enable that object to be moved.
The headset is the set of components on a bicycle that provides a rotatable interface between the bicycle fork and the head tube of a bicycle frame. The tube through which the steerer of the fork passes is called the head tube. A typical headset consists of two cups that are pressed into the top and bottom of the headtube. Inside the two cups are bearings which provide a low friction contact between the bearing cup and the steerer.
A bicycle fork is the part of a bicycle that holds the front wheel.
The caster angle or castor angle is the angular displacement of the steering axis from the vertical axis of a steered wheel in a car, motorcycle, bicycle, other vehicle or a vessel, as seen from the side of the vehicle. The steering axis in a car with dual ball joint suspension is an imaginary line that runs through the center of the upper ball joint to the center of the lower ball joint, or through the center of the kingpin for vehicles having a kingpin.
A swingarm, or "swinging arm" (UK), originally known as a swing fork or pivoted fork, is a single or double sided mechanical device which attaches the rear wheel of a motorcycle to its body, allowing it to pivot vertically. The main component of the rear suspension of most modern motorbikes and ATVs, it holds the rear axle firmly, while pivoting to absorb bumps and suspension loads induced by the rider, acceleration, and braking.
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.
The Yamaha XS650 is a mid-size motorcycle made by Yamaha Motor Company. The standard model was introduced in October 1969,and produced through 1979. The "Special" cruiser model was introduced in 1978 and produced through 1985. The XS650 began with the 1955 Hosk SOHC 500 twin. After about 10 years of producing 500 twin, Hosk engineers designed a 650 cc twin. Later the Hosk company was acquired by Showa Corporation, and in 1960 Yamaha had bought Showa with Hosk's early design of 650 cc twin.
Bicycle and motorcycle dynamics is the science of the motion of bicycles and motorcycles and their components, due to the forces acting on them. Dynamics falls under a branch of physics known as classical mechanics. Bike motions of interest include balancing, steering, braking, accelerating, suspension activation, and vibration. The study of these motions began in the late 19th century and continues today.
A motorcycle's suspension serves a dual purpose: contributing to the vehicle's handling and braking, and providing safety and comfort by keeping the vehicle's passengers comfortably isolated from road noise, bumps and vibrations.
A downhill bike is a full suspension bicycle designed for downhill cycling on particularly steep, technical trails. Unlike a typical mountain bike, durability and stability are the most important design features, compared to lighter, more versatile cross-country bikes. Downhill bikes are primarily intended for high-speed descent, and downhill riders will usually push, or shuttle via chairlifts or motorized vehicles, to the trailhead. Downhill bikes share similarities with freeride bikes due to their large strong frames and increased travel.
A motorcycle fork connects a motorcycle's front wheel and axle to its frame, typically via a yoke, also known as a triple clamp, which consists of an upper yoke joined to a lower yoke via a steering stem, a shaft that runs through the steering head, creating the steering axis. Most forks incorporate the front suspension and front brake, and allow the front wheel to rotate about the steering axis so that the bike may be steered. Most handlebars attach to the top clamp in various ways, while clip-on handlebars clamp to the fork tubes, either just above or just below the upper triple clamp.
A rake is an angle of slope measured from horizontal, or in some contexts from a vertical line 90° perpendicular to horizontal.
Bicycle and motorcycle geometry is the collection of key measurements that define a particular bike configuration. Primary among these are wheelbase, steering axis angle, fork offset, and trail. These parameters have a major influence on how a bike handles.
A motorcycle frame is a motorcycle's core structure. It supports the engine, provides a location for the steering and rear suspension, and supports the rider and any passenger or luggage. Also attached to the frame are the fuel tank and battery. At the front of the frame is found the steering head tube that holds the pivoting front fork, while at the rear there is a pivot point for the swingarm suspension motion. Some motorcycles include the engine as a load-bearing stressed member; while some other bikes do not use a single frame, but instead have a front and a rear subframe attached to the engine.
The stem is the component on a bicycle that connects the handlebars to the steerer tube of the bicycle fork. Sometimes called a goose neck, a stem's design belongs to either a quill or threadless system, and each system is compatible with respective headset and fork designs:
BMW Motorrad is the motorcycle brand and division of German automotive manufacturer, BMW. It has produced motorcycles since 1923, and achieved record sales for the fifth year in succession in 2015. With a total of 136,963 vehicles sold in 2015, BMW registered a growth of 10.9% in sales in comparison with 2014. In May 2011, the 2,000,000th motorcycle produced by BMW Motorrad was an R1200GS.
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|---|---|---|
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| Drivetrain | ||
| Cabling | ||
| Peripherals | ||