Fixed-gear bicycle

In Australia (and for some in the United States), "fixed-wheel" is the normal term for the subject of this article, meaning the opposite of freewheel, and "fixed-gear" refers to a single-speed bicycle.

A fixed-gear bicycle (or fixed-wheel bicycle, commonly known as a fixie) is a bicycle that has a drivetrain with no freewheel mechanism. The freewheel was developed early in the history of bicycle design but the fixed-gear bicycle remained the standard track racing design. More recently the "fixie" has become a popular alternative among mainly urban cyclists, offering the advantages of simplicity compared with the standard multi-geared bicycle.

Most bicycles incorporate a freewheel to allow the pedals to remain stationary while the bicycle is in motion, so that the rider can coast, i.e., ride without pedalling using the forward or downhill energy of the bike and rider. A fixed-gear drivetrain has the drive sprocket (or cog) threaded or bolted directly to the hub of the back wheel, so that the rider cannot stop pedalling. When the rear wheel turns, the pedals turn in the same direction.^[1] This allows a cyclist to apply a braking force with the legs and bodyweight, by resisting the rotation of the cranks. It also makes it possible to ride backwards although learning to do so is much more difficult than riding forward. 

As a general rule, fixed-gear bicycles are single-speed. A derailleur cannot be fitted because the chain cannot have any slack, but hub gearing can, for example a Sturmey-Archer fixed-gear 3-speed hub, in which case is a fixed-gear multi-speed arrangement. Most fixed-gear bicycles only have a front brake, and some have no brakes at all.^[2]

Uses

The track bicycle is a form of fixed-gear bicycle used for track cycling in a velodrome. But since a fixed-gear bicycle is just a bicycle without a freewheel, a fixed-gear bicycle can be almost any type of bicycle.^[3]

Some road racing and club cyclists used a fixed-gear bicycle for training during the winter months, generally using a relatively low gear ratio, believed to help develop a good pedalling style.^[4] In the UK until the 1950s it was common for riders to use fixed-gear bicycles for time trials. The 1959 British 25 mile time trial championship was won by Alf Engers with a competition record of 55 minutes 11 seconds, riding an 84 inch fixed-gear bicycle.^[5][6][7][8] The fixed-gear was also commonly used, and continues to be used in the end of season hill climb races in the autumn.^[9][10] A typical club men's fixed-gear machine would have been a "road/path" or "road/track" cycle. In the era when most riders only had one cycle, the same bike when stripped down and fitted with racing wheels was used for road time trials and track racing, and when fitted with mudguards (fenders) and a bag, it was used for club runs, touring and winter training.^{[11][12][13][14]} By the 1960s, multi-gear derailleurs had become the norm and riding fixed-gear on the road declined over the next few decades.^[15] Recent years have seen renewed interest and increased popularity of fixed-gear cycling.^[16]

In urban North America and similar areas in other English-speaking cities, fixed-gear bicycles have achieved significant popularity, with the rise of discernible regional aesthetic preferences for finish and design details.^[17]

Dedicated fixed-gear road bicycles are being produced in greater numbers by established bicycle manufacturers. They are generally low in price^[18] and characterized by relaxed road geometry, as opposed to the steep geometry of track bicycles.^[19]

Fixed-gear bicycles are also used in cycle ball, bike polo and artistic cycling. Bike messengers frequently use fixies due to their durability, low maintenance, simplicity and ease.

A fixed-gear bicycle is particularly well suited for track stands, a manoeuvre in which the bicycle can be held stationary, balanced upright with the rider's feet on the pedals.^[20]

Advantages and disadvantages

One of the perceived main attractions of a fixed gear bicycle is low weight. Without the added parts required for a fully geared drive train—derailleurs, shifters, cables, cable carriers, multiple chain rings, freewheel hub, brazed-on mounting lugs—a fixed gear bicycle weighs less than its geared equivalent. The chain itself is subject to less sideways force and will not wear out as fast as on a derailleur system.^[21] Also, a fixed gear drivetrain is more mechanically efficient than any other bicycle drivetrain, with the most direct power transfer from rider to the wheels. Thus, a fixed gear requires less energy in any given gear to move than a geared bike in the same gear.^[2]

In slippery conditions some riders prefer to ride fixed because they believe the transmission provides increased feedback on back tire grip. However, there is also an increased risk of loss of control in such conditions. Especially when taking into account the large number of riders who ride brakeless, which entails the rider to braking by stopping the motion of the pedals in mid-rotation, causing the rear wheel to lock in place, allowing the bicycle to skid and slow down from kinetic friction (see below).^[22]

Descending any significant gradient is more difficult as the rider must spin the cranks at high speed (sometimes at 170 rpm or more), or use the brakes to slow down. Some consider that the enforced fast spin when descending increases suppleness or flexibility, which is said to improve pedalling performance on any type of bicycle; however the performance boost is negligible compared to the benefits of riding a free wheel.^[23]

Riding fixed is considered by some to encourage a more effective pedaling style, which it is claimed translates into greater efficiency and power when used on a bicycle fitted with a freewheel. It allows for the rider to engage in and practice proper cadence, which is the balanced and rhythmic flow of pedaling, enhancing performance for both cyclist and bicycle.^[24]

When first riding a fixed gear, a cyclist used to a freewheel may try to freewheel, or coast, particularly when approaching corners or obstacles. Since coasting is not possible this can lead to a "kick" to the trailing leg, and even to loss of control of the bicycle. Riding at high speed around corners can be difficult on a fixed-gear bicycle, as the pedals can strike the road, resulting in loss of control.

Brakeless

Many urban fixed-gear riders think brakes are not strictly necessary, and brakeless fixed riding has a cult status in some areas.^[25] Brakes and their cables are said to add extra bulk to the simple appearance of a fixed gear bicycle, and they prevent trick manoeuvres that involve spinning the front wheel in a full circle.

Other riders dismiss riding on roads without brakes as an affectation, based on image rather than practicality.^[26] Riding brakeless can be dangerous, is prohibited by law in many jurisdictions, and may jeopardize the chances of a claim in the event of an accident.^[27]

Technique

It is possible to slow down or stop a fixed-gear bike by resisting the turning cranks, and a rider can also lock the rear wheel and skid to slow down or stop on a fixed-gear bicycle. Such a move is initiated by unweighting the rear wheel while in motion by shifting the rider's weight slightly forward and pulling up on the pedals using clipless pedals or toe clips and straps. The rider then stops turning the cranks, thus stopping the drivetrain and rear wheel, while applying body weight in opposition to the rotation of the cranks. This causes the rear wheel to skid, and slow the bike. The skid can be held until the bicycle stops or until the rider desires to continue pedalling again at a slower speed. The technique requires a little practice and using it while cornering is generally considered dangerous.^[28][29] A wet surface further reduces the effectiveness of this method.

On any bike with only rear wheel braking, the maximum deceleration is significantly lower than on a bike equipped with a front brake.^[30] As a vehicle brakes, weight is transferred towards the front wheel and away from the rear wheel, decreasing the amount of grip the rear wheel has. Transferring the rider's weight back increases rear wheel braking efficiency, but a front wheel fitted with an ordinary brake might provide 70% or more of the braking power when braking hard (see Weight transfer).

Legality

Australia – Bicycles are regarded as vehicles under the Road Rules in every state. A bike is required by law to have at least one functioning brake.^[31]

Belgium – All bicycles are required to have easy-to-hear bells and working brakes on both wheels. Lights and reflectors are not required on race, mountain, and children's bikes when not used after dark. Other (normal) bikes need reflectors and lights. These lights may be attached to your body and may blink.^[32]

Canada – Laws vary by province, and are controlled by highway and traffic acts.^[33] In both Ontario and Quebec a rear brake is required, and not having one may subject you to a fine.^[34]

Denmark – All bicycles are required to have working brakes on both wheels, reflectors, and bells.^{[citation needed]}

France – A bike must have 2 brakes, 2 lights, numerous reflectors, and a ringer to be approved for road traffic. The laws are rarely enforced, however, and the sight of all kinds of non-officially-approved bikes is common.^[35]

Germany – All bicycles are required to have working brakes on both wheels, reflectors, and bells.^[36] A local court in Bonn accepted that the fixed-gear mechanism was a suitable back brake,^[36] but high-profile crackdowns specifically targeted fixed-gear bicycles in Berlin in an attempt to control what police described as a "dangerous trend"^[37][38]

Netherlands – All bicycles are required to have an adequate brake system.^[39]

New Zealand – By law all bicycles must have a minimum of "...a good rear brake..."–and those made since 1 January 1988 must also have "...a good front brake..."^[40]

Spain – All bicycles are required to have an adequate brake system on front and rear wheels, plus a bell.^[41]

United Kingdom – The Pedal Cycles Construction and Use Regulations 1983 require pedal cycles "with a saddle height over 635 mm to have two independent braking systems, with one acting on the front wheel(s) and one on the rear". It is commonly thought that a front brake and a fixed rear wheel satisfies this requirement .^[42]

United States – The use of any bike without brakes on public roads is illegal in many places, but the wording is often similar to "...must be equipped with a brake that will enable the person operating the cycle to make the braked wheels skid on dry, level and clean pavement..."^[43] which some have argued allows the use of the legs and gears.^[44] The retail sale of bikes without brakes is banned by the U.S. Consumer Product Safety Commission^[45] – but with an exception for the "track bicycle" (...a bicycle designed and intended for sale as a competitive machine having tubular tires, single crank-to-wheel ratio, and no free-wheeling feature between the rear wheel and the crank...).^[46]

Conversion

Many companies sell bicycle frames designed specifically for use with fixed-gear hubs. A fixed-gear or track-bike hub includes special threads for a lockring that tightens in the opposite (counter-clockwise) direction compared with the cog. This ensures that the cog cannot unscrew when the rider "backpedals" while braking.^[47]

For a variety of reasons, many cyclists choose to convert freewheel bicycles to fixed gear. Frames with horizontal dropouts are straightforward to convert, frames with vertical dropouts less so.^[48] One method is to simply replace the rear wheel with a wheel that has a track/fixed hub. Another is to use a hub designed for use with a threaded multi-speed freewheel. Such a hub only has the normal right-handed threads for the cog and not the reverse threads for the lockrings used on track/fixed hubs. The sprocket on a hub without a lockring may unscrew while back pedalling. Even if a bottom bracket lockring is threaded onto the hub, along with a track sprocket, because the bottom-bracket lockring is not reverse threaded, the possibility still exists that both the sprocket and locknut can unscrew. Therefore it is recommended to have both front and rear brakes on a fixed-gear bicycle using a converted freewheel hub in case the cog unscrews while back pedaling. It is also advisable to use a thread sealer for the cog and bottom bracket locking. The rotafix (or "frame whipping") method may be helpful to securely install the sprocket.

Bicycles with vertical dropouts and no derailleur require some way to adjust chain tension. Most bicycles with horizontal dropouts can be tensioned by moving the wheel forward or backward in the dropouts. Bicycles with vertical dropouts can also be converted with some additional hardware. Possibilities include:

• An eccentric hub or bottom bracket allows the off center axle or bottom bracket spindle to pivot and change the chain tension.
• A Ghost or floating chainring is an additional chainring in the drive train between the driving chainring and sprocket. The top of the chain moves it forward at the same speed that the bottom of the chain moves it backwards, giving the appearance that it is floating in the chain.
• A magic gear—the right math can calculate a gearing ratio to fit a taut chain between the rear dropout and bottom bracket. Also, using a chain half link and slightly filing the dropouts to increase the width of the slot increases the chances of finding a magic gear. It is worth noting that the magic gear setup is controversial, due to inevitable chain stretch and subsequent slippage that can lead to serious injury.

Separate chain tensioning devices, such as the type that attaches to the dropout gear hanger (commonly used on single speed mountain bikes) cannot be used because they are damaged as soon as the lower part of the chain becomes tight.

Additional adjustments or modification may be needed to ensure a good chainline. The chain should run straight from the chainring to the sprocket, therefore both must be the same distance away from the bicycle's centerline. Matched groupsets of track components are normally designed to give a chainline of 42 mm, but conversions using road or mountain bike cranksets often use more chainline. Some hubs, such as White Industries' ENO, or the British Goldtec track hub, are better suited to this task as they have a chainline greater than standard. Failure to achieve good chainline, at best, leads to a noisy chain and increased wear, and at worst can throw the chain off the sprocket. This can result in rear wheel lockup and a wrecked frame if the chain falls between the rear sprocket and the spokes. Chainline can be adjusted in a number of ways, which may be used in combination with each other:

• Obtaining a bottom bracket with a different spindle length, to move the chainring inboard or outboard
• Choosing a bottom bracket with two lockrings, which gives fine adjustment of chainring position
• Respacing and redishing the rear wheel, where permitted by the hub design
• Placing thin spacers under the bottom bracket's right-hand cup (Sturmey-Archer make a suitable 1/16" spacer) to move the chainring outboard
• Placing thin spacers between the chainring and its stack bolts to move it inboard (if the chainring is on the inside of the crank spider) or outboard (if the ring is on the outside of the spider)
• Placing thin spacers between the hub shoulder and the cog. This is recommended in the case of a freewheel-threaded hub, which has sufficiently deep threads for this operation.

Usually, the rear hub is the best component on which you can operate chainline adjustments, especially on threaded hubs. If you have a track hub, it’s better to operate on the bottom bracket or - for minor shifts - on the crankset. The same occurs if you have a flip-flop hub, because the chainline should be the same in both sides (freewheel and fixed gear).^[49]

Competition

There are many forms of competition using a fixed gear bike, most of the competitions being track races. Bike messengers and other urban riders may ride fixed gear bicycles in alleycat races, including New York City's famous fixed-gear-only race Monstertrack alleycat.

There are also events based on messenger racing, such as Mixpression, which has been held nine times in Tokyo. Trick demonstrations have been held since the late 1800s in the US and Europe;^[50] while they continued into a competitive form in Europe (Artistic Cycling), subsequent to the recent widespread popularity and advancement of fixed gear bikes, trick competitions have also now established themselves at venues in the US and Asia.^[51] European competitions include solo and team balletic movements on a controlled, flat surface; US and Asian competitions often include "park" and "flatland" styles and venues, a la BMX. Other competitions include games of "foot down" and bike polo.

In 2006, Adventures for the Cure made a documentary film on riding across the United States on fixed gears; they repeated this feat as a 4-man team at the 2008 Race Across America.

Fixed gear riders sharing the specific philosophy are also seen at the Single Speed World Championships.

Maintenance and upkeep

Maintaining a fixed gear is relatively easy because it has fewer parts than a geared bicycle. The sprocket should be checked regularly to make sure there is no damage to any teeth and that no object is grinding it as it turns with the rear wheel. The chainring should be checked similarly for any damage. There is an advantage to selecting a number of chainring teeth that is not a round multiple of the number of sprocket teeth (e.g. 3) because this avoids coincidence of the same chainring and sprocket teeth, and tyre contact patch, on each of the rider's power strokes. For riders who perform brakeless skid-stops, it is best to select prime-numbered chainrings (e.g. 41, 43 or 47 teeth) to guarantee that rear tyre wear is spread evenly.

It is imperative (for road riding, at least) that the chain is sufficiently tight that it is impossible for it to derail from either the chainring or sprocket. This generally equates to "no visible slack". A derailed chain can cause a variety of undesirable consequences, such as a locked rear wheel or, worst of all, destruction of the frame if the chain becomes caught around the crank arm and pulls the rear triangle forwards. On a fixed-gear bicycle without hand brakes, even a relatively benign derailment means a total loss of braking ability. Tensioning aside, a chain is significantly less likely to derail if the chainline is accurate and the chain is a traditional "full bushing" type with limited lateral flexibility. Because the difference between a tight and a slack chain equates to only very minor elongation of the links, chain tension should be visually checked at least weekly, especially if the bicycle is ridden in wet or dirty conditions.

As with any other bicycle, the chain should be checked making sure the master link is securely latched. The chain can be lubricated monthly for smooth riding.^[52] Also, as needed, the brakes should be tightened as they wear and tire condition observed for possible puncture locations. Air pressure in the tires, tire alignment, brake handle placement, and rust should be monitored on a daily basis because they can change very easily during a jarring ride.

Subculture

Australia

Australian retail is typically 4 years behind trends from the United Kingdom and United States.^[53] Until recently, the Australian Fixie culture has been small. However, with the strong Australian dollar and cost effective manufacturing and importing from China, Australia has seen many new online stores capitalise on the cheap, steel frames commonly imported to the UK and US. Online stores in Australia ship partly assembled bikes from warehouses direct to the consumer's door, undercutting typical brick and mortar stores considerably.^[54]

Sweden

Community

The fixed-gear movement is growing in Sweden. A cornerstone of the Swedish fixed-gear society is the Internet based forum Fixedgear.se, with over 2300 registered members . This makes up for the main meeting ground and discussion forum for Swedish fixed-gear riders and enthusiasts.^{[citation needed]}

There are also several bicycle clubs throughout Sweden with a fixed-gear niche. Komet Club Rouler is a club based in Gothenburg, annually arranging Svart Katt and other fixed-gear oriented activities. Svart Katt has been internationally recognized and is considered Sweden’s largest alley cat by number of participators, according to Cog Magazine.^[55] KCR’s equivalent in Malmö is called Pista Malmø,^[56] arranging ”Thursday's rides” every Thursday, for all bikes and riders. Stockholm also has its own informal fixed gear bicycle club, called Fista Sthlm.

Popularity factors

Several factors contribute to the recent rise in popularity of fixed-gear bicycle. A rider from Stockholm interviewed for an article about the phenomenon notes that riding a bike imparts a feeling of freedom to the rider. You are free to go wherever you want, whenever you want. A sense of belonging is also important; as the rider says, "all who cycle are my friends". Riders unknown to each other commonly greet each other when on bikes. As in many subcultures, this feeling of belonging is a key factor in recruiting and retaining participants.^[57]

The fact that many fixie riders ride brakeless in defiance of local law could also be viewed as a contributing factor to its popularity; it provides an outlet for minor rebellion.^[58]

Russia

Fixed Gear Moscow

During the year 2007, a few activists started assembling and riding fixed gear bikes in Moscow.^[59] There had been people riding fixed gear bikes on the street in Moscow prior that time, but it had never developed into any feasible subculture. And in 2007 that situation started to change, since fixed gear bicycles started appear more and more in foreign media, attracting more people to its concept.

The group of riders used to communicate with each other and share ideas for rides in a blog system Live Journal under a Fixed Gear Moscow community. As interest and the number of people willing to join in grew, the community was separated from Live Journal and a separate web site was created to host the blog and the forum.

Up till 2012 Fixed Gear Moscow organized numerous alleycat races, tournaments and other events to keep community growing. Several side projects were initiated by members of Fixed Gear Moscow and are still in development.

China

Around 2012, throughout China, fixed gear bikes have become a popular trend among teenagers. The bikes are typically painted in two or three fluorescent colours. They normally cost approximately $160 to $320 USD.

Circus bikes

A fixed gear bike is also used in the circus arts. When the saddle and handlebars are at the same height, an acrobat can stand on the handlebars and saddle and perform acrobatic exercises, sometimes involving multiple people, while continuing to circle the circus ring.

In media

The 2012 film Premium Rush uses a "fixie" as a running plot device. Wilee, the lead character played by Joseph Gordon-Levitt, works as a bike messenger in Manhattan, and his fellow riders rib him about his enthusiasm for his fixed-gear steel-frame bike with no brakes. He avoids one confrontation by pedaling the bicycle backwards, and he successfully weaves through dangerous traffic, but he also gets into accidents because the fixed-gear style abets his avidity for speed. Wilee says, "I like to ride. Fixed gear. No brakes. Can't stop. Don't want to, either."^[60]

See also

Media related to Fixed-gear bicycles at Wikimedia Commons

• Artistic cycling
• Flip-flop hub
• List of bicycle parts
• List of cycling topics
• Track bicycle

References

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