Quick release skewer
Encyclopedia
Bicycle wheel
A bicycle wheel is a wheel, most commonly a wire wheel, designed for bicycle. A pair is often called a wheelset, especially in the context of ready built "off the shelf" performance-oriented wheels....
to a bicycle
Bicycle
A bicycle, also known as a bike, pushbike or cycle, is a human-powered, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A person who rides a bicycle is called a cyclist, or bicyclist....
. It consists of a rod threaded on one end and with a lever operated cam
Cam
A cam is a rotating or sliding piece in a mechanical linkage used especially in transforming rotary motion into linear motion or vice-versa. It is often a part of a rotating wheel or shaft that strikes a lever at one or more points on its circular path...
assembly on the other. The rod is inserted into the hollow axle
Axle
An axle 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 its surroundings, with the wheels rotating around the axle. In the former case, bearings or bushings are provided at the mounting points where the axle...
of the wheel, a 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
Bicycle frame
A bicycle frame is the main component of a bicycle, on to 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...
and replaced without using tools by opening and closing the cam lever, thus more quickly than wheels with solid axles and hex nuts. On the negative side, a quick-release hub renders a wheel more vulnerable to theft. Also, care must be taken to ensure that the mechanism is properly tightened.
Similar quick-release mechanisms are also used to operate seatpost
Seatpost
A bicycle seatpost, seatpin, saddlepole, saddle pillar, or saddle pin is a tube that extends upwards from the bicycle frame to the saddle. The amount that it extends out of the frame can usually be adjusted, and there is usually a mark that indicates the minimum insertion...
clamps, and the collapsing stem of folding bicycle
Folding bicycle
A folding bicycle is a bicycle designed to fold into a compact form, facilitating transport and storage. When folded, the bikes can be more easily carried into buildings and workplaces or onto public transportation or more easily stored in compact living quarters or aboard a car, boat or plane...
s and kick scooter
Kick scooter
A kick scooter or push scooter, originally scooter, is a human-powered vehicle with a handlebar, deck and wheels that is propelled by a rider pushing off the ground. The most common scooters today have two hard small wheels, are made primarily of aluminium and fold for convenience...
s.
History
The mechanism was invented in 1927 by Tullio CampagnoloTullio Campagnolo
Gentullio Campagnolo was an Italian racing cyclist and inventor. He patented the quick release skewer and founded the Campagnolo bicycle component company....
, an Italian
Italy
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...
bicycle racer. He was frustrated when he needed to repair a flat tire during a race. The weather had turned cold, and his hands were numb, so he could not operate the wingnuts which retained the wheel. He had been well-placed prior to the puncture, but lost valuable time. Another Campagnolo invention that made use of the quick-release mechanism was the Cambio Corsa, a multi-gear changing system consisting of a rear wheel quick-release lever with a mechanical extension that placed the lever itself near the bicycle's saddle, combined with a fork that served as a primitive version of a rear derailleur (without idler pulleys to take up slack), that also had a control lever near the bicycle saddle. This innovation enabled bicycle riders quickly to change gears while in motion by releasing the axle, moving the rear wheel slightly forward by applying tension to the chain, actuating the fork to change to a larger sprocket, and tightening the quick release again; or else releasing the axle, actuating the fork to change to a smaller sprocket, moving the wheel slightly rearward by braking, and tightening the quick release again. The quick-release mechanism, along with other innovations and high standards of manufacture, enabled Campagnolo
Campagnolo
Campagnolo is an Italian manufacturer of high-end bicycle components with headquarters in Vicenza, Italy. The components are organised as groupsets and are a near-complete collection of a bicycle's mechanical parts. Campagnolo's flagship components are the Super Record, Record, and Chorus...
to become a leading road cycling
Road bicycle racing
Road bicycle racing is a bicycle racing sport held on roads, using racing bicycles. The term "road racing" is usually applied to events where competing riders start simultaneously with the winner being the first to the line at the end of the course .Historically, the most...
and track cycling
Track cycling
Track cycling is a bicycle racing sport usually held on specially built banked tracks or velodromes using track bicycles....
component manufacturer.
Usage
Quick releases tend not to be used on certain types of bicycles, such as utility bicycles (with a single speed or hub gears) or track bicycleTrack bicycle
A track bicycle or track bike is a bicycle optimized for racing at a velodrome or outdoor track. Unlike road bicycles, the track bike is a fixed-gear bicycle and so has a single gear and neither freewheel nor brakes. Tires are narrow and inflated to high pressure to reduce rolling resistance...
s, partly because of tradition and partly because there is less need for quick removal of wheels without using tools.
Quick releases are sometimes recommended against with the use of disk brakes because of the need for the axle attachment to withstand braking forces.
Over the years quick release mechanisms have been adopted as the primary wheel release devices by the average rider. However, as Sheldon Brown (bicycle mechanic)
Sheldon Brown (bicycle mechanic)
Sheldon Brown was an American bicycle mechanic and technical authority on bicycles. He contributed to numerous print and online sources related to bicycling, bicycle mechanics and maintenance, including his own website — and received numerous awards for his contributions.-Biography:Brown...
notes this change has come with some difficulty:
"Because some bicycle users are competent enough to remove their front wheels but not competent enough to secure them properly when they reinstall them, virtually all new bike purchasers have been deprived of the handy function of quick-release front wheels.
This has been done by encumbering fork ends with extra hardware, ridges or lumps that keep the wheel sort-of attached even if it has been installed by someone who doesn't know what he or she is doing. Unfortunately, this means that the quick-release mechanism must be re-adjusted each time it is used, seriously slowing down the operation.
Since this extra stuff was installed as a defense against frivolous lawsuits by ambulance-chasing shysters, the extra bumps are sometimes known as "lawyer lips" or "lawyer tabs."
As "lawyer lips" have become the norm, they have gradually become more important than they originally were, for two reasons:
* The prevalence of these secondary rentention systems in front, and vertical dropouts in the rear has caused the proliferation of inferior skewer designs that are cheaper to manufacture, but much less secure than traditional skewers.
See my Article on Quick Release Skewers.
* The introduction of disc brakes has caused increased vulnerability of the front axle and skewer, due to the disc brake applying an ejection force that tends to pull the axle out of the fork."
The debate over quick release use as illustrated by Brown, has become a national issue due to several lawsuits brought on by various people including a group of mothers who claim their children were injured due to innocently incorrect use of quick releases.
The quick-release levers are usually on the left side of the bike, though some prefer to have them on the right if a disc brake is on the left.
Mountain bikers often prefer to point the lever aft, lest it catch on undergrowth and be pulled open.
Variations
External links
- Article on Quick release skewers by Sheldon BrownSheldon Brown (bicycle mechanic)Sheldon Brown was an American bicycle mechanic and technical authority on bicycles. He contributed to numerous print and online sources related to bicycling, bicycle mechanics and maintenance, including his own website — and received numerous awards for his contributions.-Biography:Brown...