Terminology index - a list of bike part names and cycling concepts

  • This question and its answers list the names of bike parts and cycling concepts.

    Some Rules

    • Make sure you only put one term per answer!

    • Try to include an image if applicable

    • Include sources that contain detailed information

    • Add a link to the index in this question using edit.

    Also, I made this a community wiki, so that anyone will be able to edit it, and to stop rep-hoarding

    There's a handy reference at the Park Tool Co. website, a bike repair map; it's a diagram of a bike with all the parts labeled, and is very handy! At the moment, the diagram is up at parktool.com/blog/repair-help. (They've changed the URL in the past, so this link may break.)

    A road bike has the following parts (source):

    enter image description here

    A mountain bike has the following parts (source):
    enter image description here

    Edit: This page is meant to identify what things or concepts are (as per this thread in meta). If you want to recommend an accessory or a specific product you've found handy, please use the accessories page.

    One term per answer please - would be beneficial.

    Should we add an "Anything not mentioned here" link? (With a link to http://www.sheldonbrown.com/glossary.html, of course.)

    Is there a way to link to a specific answer, so that in future questions you can use one of these terms and link to it for reference?

    Kevin: Under the bulk of the answer, there is a 'Link' hyperlink, which will link to the answer (its right above comment)

    I started a discussion in meta about this thread and its twin: Glossary threads

    Whilst this is no doubt useful, it's not actually a question is it?

    @MarkIngram: useful things that aren't actually questions are what community wikis are for.

    This is great. I have opened a feature request on Meta.SO in a similar vein

    Is there any way to make a question 'sticky' so that a faq like this one is easier to find?

    It's already the top question in the 'faq' tab, on the questions page. Not sure if there's a way to 'feature' a question.

    @mgb: Not that I'm aware of, however if you click on Questions then faq this question is right at the top.

    @zigdon - If we just keep adding to this, it'll stay near the top of the questions list.

    This page could use some more love. Maybe if people keep linking to individual terms here, more people will know about this page.

    Consider adding Tubeless?

    @NeilFein That FAQ link now goes to the [tour] page, and it doesn't seem to a link back here. I haven't found a FAQ page, has it changed?

    @andy256 - Yeah, they changed how the help pages work some time back; will try and sort this.

    @andy256 Unfortunately the tour page isn't editable by mods. Probably best to just leave this be.

    @ow3n sure go ahead and add tubeless, and edit the index to point to it.

  • Bicycle-Shaped Object (BSO)

    A derogatory term for a very cheaply produced bike with very low quality components. The components can be hard to maintain due to poor tolerances. BSOs are often sold at non-specialty retail stores.

    The etymology of the term is uncertain. It appears in use in some parts of the English-speaking world. It may originate in the UK, as discussed at the link. Other languages may use terms equivalent to supermarket bike or department store bike. These terms are likely to be understood in English as well.

    example BSO

    For instance the BSO pictured is being sold in the UK by ASDA (owned by Walmart) for £75. These bikes tend to be mass produced and sold in flat pack boxes for self-assembly.

    Purchasers of lower-end bicycles tend to be less experienced cyclists who focus on price. Many BSOs carry features which are included for marketing purposes but are unnecessary for the typical end-user. Such features may include front and rear suspension, wide off-road style tyres and an excessive number of gear ratios. For cyclists who are riding on city streets or smooth trails, these features are unnecessary. Including these features reduces the budget available for better components elsewhere.

    It is more advisable to search for a cheap second-hand bike in a similar price range from a more experienced cyclist or on eBay than to go for one of these.

    I softened the language a bit. I agree with you about BSOs, but the situation isn't quite that clear -- and people do occasionally tour on them. (I'll try to dig up a link for that last.)

    "An impassioned guide on why not to buy a cheap Bike or BSO" http://www.southcoastbikes.co.uk/articles.asp?article=NO_BSO

    Suspension - it's not just that it's unnecessary for typical users, but that cheap suspension will add weight and absorb pedalling energy for little or no benefit. (An unpractised rider on pot-holed roads may well benefit from wide tyres though, if not knobbly ones). Also, the typical bike shaped object is heavy, being cheap steel tubes which are both large (to imitate the look of better aluminium frames) and thick-walled (to compensate for cheap steel with cheap welding being weaker). The one illustrated is far from the worst available.

  • Door Zone

    The area next to parked cars that a suddenly opened door would cover. A hazard that you should avoid.

    enter image description here

    Satirical portrayal of Santa Monica bike lane design; it illustrates the "door zone" concept well.

    Cycling in the Door Zone reduces your ability to react to hazards emerging from the space between parked vehicles. These may include unobservant pedestrians, inadequately restrained dogs (whose leads can reduce your options), sports equipment and children chasing sports equipment.

    Drivers entering the road from a driveway, forecourt or junction are less likely to observe a cyclist who is not occupying the space where oncoming motor vehicles are expected to be observed. This contributes to the SMIDSY(Sorry mate, I didn't see you) phenomenon.

    I've never seen this before in the UK. Interesting.

    @Amb100: you've never seen a bike lane that ran through the area doors would open into? The "DOOR LANE" thing isn't real, but the configuration of bike lane in door zone is common in the US.

    Oh I see. I thought it was a good idea.

    Also known as the death zone. As a rider goes slower, they're more likely to be riding closer to the kerb and parked cars. Faster riders tend to move out more and into the traffic lane.

  • LBS

    LBS is the acronym commonly used for Local Bike Shop. The term is usually used when comparing small, privately owned shops with large chains, big box stores, and internet shops.

    The best local bike shops usually have trained staff who have many years of experience in selling, maintaining, and repairing bicycles and have a well-equipped repair workshop. They can special order parts and let you know if a modification you want to make will work -- and how to make it work. As with all things, local bike shops vary in terms of their experience (and attitude) and it pays to shop around to find a LBS that matches your interests and orientation.

    Large department or chain stores, on the other hand, often sell BSOs that they assemble using staff who often have little to no background in bicycle mechanics. They cannot repair or maintain the BSOs they sell and your only recourse often is to just return the bicycle if it is still under warranty.


  • Presta Valve / Presta Tube

    aka Sclaverand valve (SV) or French valve

    alt text

    The Presta valve is a valve commonly found in high pressure road style and many mountain bicycle inner tubes. The air pressure in an inflated tire holds the inner valve body shut. A small screw and captive nut on the top of the valve body permits the valve to be screwed shut and ensure that it remains tightly closed. The nut must be unscrewed to permit airflow in either direction (this must be done before attaching a pump). The screw remains captive on the valve body even when unscrewed fully; it is tightened again after the tire is inflated and the pump removed.

    Presta valve
    photo credit

    Photo sequence of removing the dust cap then unscrewing the nut so the valve is ready to inflate.

    A Presta valve adapter can be used to fill a Presta tube with a normal Schrader-style air pump, although many pumps today come with a built-in adapter.

    For a video tutorial on the use of the adapter, check out this video at BicycleTutor.com

    More information: Presta valve (Wikipedia).

    Go to Schrader valve.

    Go to Dunlop valve.

  • Cadence

    Cadence is the number of revolutions of the crank per minute.

    Cyclists typically have a preferred cadence at which they feel most comfortable, and on bicycles with many gears it is possible to stick to a favourite cadence at a wide range of speeds. Recreational and utility cyclists typically cycle around 60–80 rpm; racing cyclists around 80–120 rpm and sprinters up to 170 rpm for short bursts. The professional racing cyclist and Tour de France champion Lance Armstrong is known for his technique of keeping up high cadences of around 110 rpm for hours on end to improve efficiency1

    1 http://en.wikipedia.org/wiki/Cadence_(cycling)

    If you are getting pain in your knees, it could be that your cadence is too low. A cadence between 80-100 will probably reduce knee pains, as stated in bicycling.com or more detailed at Cycling Performance Tips web site.

    EDIT by Ivor

    To answer a comment below on beginners and cadence...

    Cadence is critical to enjoying your cycling and if you become involved in cycle racing, winning. Cadence is something that is learned and once learned you promptly forget about it and move onto getting other things right :)

    For a beginner:

    1. Get to know your gears.

      • Drop it into a high gear (big chainring on the front, small cog on the back)

      • Feel how hard it is to push (Pay attention to where you feel the muscles working)

      • Drop it into a low gear (smallest chainring on the front, largest cog on the back)

      • Feel how free your legs spin (Pay attention to how you bounce in the saddle :) If you are bouncing, then you are spinning too much, i.e. your cadence is too high)

      • Find a combination of gears that allow you to spin your pedals without feeling undue pain in your muscles and doesn't make you feel out of breath. (Ignore the speed for the moment)

      • Get to know this "sweet spot", ride around in this gear for a while and adjust your gears to suit your speed so that you balance not being out of breath and over exertion. (Watch out for the bounce in the saddle :) )

    2. The next thing to take into account is how fast you want to go

      • Without a bike computer? - Your feeling of relative speed is good enough

      • With a bike computer? - Set a reasonable target, say 20 km/h

      • Using the gears you have selected for your sweet spot, try to hit your target speed.

      • Once you hit it, can you keep it going? For how long? - Set a reasonable target say 5 mins.

      • When you have finished this, where does it hurt?

      • In your chest? Out of breath big time? - You may have been spinning too much, i.e. your cadence was too high?

      • Muscles in the small of your back, quads, glutes, knees, calves groaning or hurting (not burning, burning isn't as bad as you think) - You may have been spinning too little i.e. your cadence was too low?

    3. There is an ideal cadence proposed by some sports physiologists that is somewhere between 80 to 100 turns of the pedal per minute (rpm)

      • The only way to know your cadence accurately is to have a cadence enabled bike computer and sensor.

      • The other way is to know your gear ratios (Check out BikeCalc.com)

      • For example, You are riding your bike, it has a wheel of size 700c/29 and a tyre that is 23 mm wide, with a front chainring of 34 teeth, a rear cog of 17 and you are pedalling at a speed of 20 km/h. You should then have a cadence of 79 rpm. Simples :) (Get the bike computer ;) )

    4. Get used to spinning your legs in that range of RPM, i.e. 80 to 100 rpm.

      • In all conditions, on any terrain, whatever the occasion.

      • It trains your heart and body to be cardio fit and with a stronger heart comes better stamina and greater strength.

      • Pick up the pace and work to get the legs spinning at the next level of speed.

      • Hard work and worth it.

    5. Go cycling with a group more experienced than you

      • Watch them as they cycle, see all of the different styles and high cadence

      • Listen to the experienced guys as they can advise on many many things.

    6. Enjoy it, you will have earned it :)

    We're really not here to copy and paste from Wikipedia. Are there recommended cadence rates for beginners? What users are generally concerned with cadence? Perhaps you could address concerns like these?

    I'm not sure that citing Lance Armstrong as an example is really useful, given that he achieved his performances through doping...

    @Ivor my reading of your edit is that it's not clear if bouncing on the saddle is good or not. Can you make that clear please?

    @andy256 I have taken your comments on board and modified the edit. Bouncing is definitely not good. The Quote I used to differentiate the text and have now removed it as the text is my own ramblings on cadence and I am the only one who would claim it :)

  • Clipless pedals a.k.a. clip-in or step-in pedals

    Clipless pedals require a special cleated cycling shoe that locks itself into the pedal's surface. To release a foot/shoe from a clipless pedal, the rider typically twists his/her foot outwards.

    The word "clipless" (a rather confusing term) refers to a pedal not having an older style toe clip straps.

    LOOK Pedals

    LOOK Pedals

    LOOK pedals came first and were inspired by ski bindings. LOOK pedals are commonly used on road bikes. A similar (but incompatible) pedal system is Shimano's SPD-SL system.

    SPD Pedals

    Shimano SPD

    Shimano Pedaling Dynamics or SPD pedals use a cleat that is recessed into the shoe. This allows the rider to walk normally, which is why this pedal is commonly used in mountain biking or similar disciplines, where a rider may need to walk for short distances over some obstacles. Note that Shimano's SPD-SL system is not compatible with SPD.

    Cleats used for these pedals have two holes for screws that go into a shoe.



    A type of clipless pedal, cleats and compatible shoes used mostly by road race cyclists.

    Compared to SPD, this system has bigger cleats which protrude from shoes, making walking in them awkward. Cleats for SPD-SL have three holes.

    SpeedPlay Pedals

    SpeedPlay Pedals

    Design proprietary to Speedplay products. The spring retention and release mechanism in this design is bolted to the shoe, rather than part of the pedal.

    Crank Brothers 'Eggbeaters' system

    Crank Brothers Eggbeaters

    A proprietary design that uses proprietary cleats. Used by Crankbrothers in all their clipless pedals. The most prominent example is the Eggbeaters model range looking very minimalistic.

    Toe Clips a.k.a "Rat trap"

    pedal with toe clip and strap

    Clipless pedals are called so, even though you do clip onto them — because one avoids the need for toe clips and straps.

    The word "clipless" (a rather confusing term) refers to a pedal not having these older style toe clip straps.

    This answer draws heavily from Clipless pedals (Wikipedia).

    Aren't TIME pedals kind of major? I see a lot of them (and I own a pair), but it might be some kind of local phenomenon...

    @domsterr: Feel free to edit this answer

    Added a link to clip+strap pedals, mainly to explain why clipless pedals have clips!

    Would platform pedals qualify as well, since they are 'clipless' too?

    I don't have the ability to edit (or the knowledge) but I'd encourage a bit of expansion here with shoes/cleats. See: http://bicycles.stackexchange.com/questions/20700/im-a-bit-confused-on-bike-shoe-terminology-particularly-regarding-look-keo-plu

    @DecSim good catch on the crankbrothers/spd compatibility

    Is "lollypop" as shorthand for the Speedplay pedals a common thing, or just in my circles?

  • Fixed Gear or Fixed Wheel

    AKA: Fixie

    A fixed-gear bicycle has the rear gear locked to the hub, which fixes the pedals rotation to the rear wheels rotation. In other words, you can't coast; the pedals are always in motion as long as the bike is. Track bikes are commonly fixed-gear.

    The sprocket is screwed directly onto a fixed hub. When the rear wheel turns, the pedals turn in the same direction. This allows a cyclist to stop without using a brake, by resisting the rotation of the cranks, and also to ride in reverse.

    Fixed-gear bikes are almost always single-speed (i.e. have only a single gear ratio), but internal-gear hubs without freewheels do exist.

    flip-flop hub on fixie setting

    The hub in the picture is a flip-flop hub.

    More information: http://en.wikipedia.org/wiki/Fixed_gear

    Compare with Single Speed.

    One should note that typically, horizontal dropouts are required to convert a bike from derailleur to fixed gear, since a pulley cannot be used as a chain tensioner (when you resist to brake, the pulley will be sheared off the bike). Vertical dropouts can be adopted in some cases using something like White Industries' Eccentric Rear Hub or an eccentric bottom bracket or something.

  • Schrader valve/Schrader tube

    aka "American valve" or "car valve" or "Auto valve" (AV)

    alt text

    The Schrader valve consists of a valve stem into which a valve core is threaded, and is used on virtually all automobile tires and most wider rimmed bicycle tires. The valve core is a poppet valve assisted by a spring.

    A valve cap is important on a Schrader valve because if one is not fitted, dirt and water can enter the outside of the valve, potentially jamming it or contaminating the sealing surfaces and causing a leak. Rock salt and other chemical deicers used in the winter are especially damaging for the brass components in the Schrader valve.

    Schrader valves are almost universal on car tires, meaning you can often (carefully) inflate your bike tires with the air machines at roadside garages.

    For an instruction video on patching and inflating a Schrader tube, check out this video on BicycleTutor.com.

    More information: http://en.wikipedia.org/wiki/Schrader_valve

    Go to Presta Valve.

    Go to Dunlop valve.

    I don't think it would hurt to combine this one with its sibling answer

    @Joe - Except that it makes linking to one valve or the other more difficult.

    In the UK at least this can also be referred to as the 'car type' since it's common to our car tyres. It's quite useful to use this type of valve because it means you can get your tires pumped up at petrol stations.

    What are the advantages/disadvantages of this type of valves? Do they loose more air with time? (compared to presta) Are they heavier? Easier to find pumps for it?

  • Pannier

    A pannier, pronounced pan-yer /ˈpanyər, ˈpanēər/ (US) or pan-i-er /ˈpanɪə/
    (UK) [1], is a bag designed to be mounted on the side of a bicycle rack. Bags can be made of nylon, canvas, or waterproof materials such as PVC. Panniers are most commonly carried on the rear, but smaller panniers intended for a front rack are also available.

    enter image description here

    Often erroneously called a saddlebag because a pannier on a motorcycle or horse is attached to the saddle. On a bicycle, the saddlebag mounts behind the rider from loops at the back of the saddle. The saddle bag goes athwartship – from side to side.

    Bikes that do not have rack mounts can often accept bags that strap under the handlebars, under the top tube, and behind the seatpost. Gravel bikes often do not have rack mounts, and these alternative bags are used instead. Potentially, these may affect a bike's handling more than a rack and panniers would, because the loads are carried higher on the bike.

    How do you pronounce this? pan-near, panny-air, pan-near?

    I pronounce it pan-yay, but I'm not sure how to *properly* say it.

    It's an English word that's commonly mistaken for being a french word. It's pronounced "PAN-yer", but many people say "PAN-yay".

    @freiheit - The link you put in allows for two pronunciations, I updated this entry.

    @JasonS - We should update the answer with these comments. Any idea how to phonetically represent those pronunciations? We should have Australian/NZ phonetics as well.

    @freiheit: It's an English word that *is also* a French word. That's like saying "Paris" is an English word that's commonly mistaken for a French word. In English, we pronounce "pannier" as "PAN-yer" and "Paris" as "PAIR-iss" but in French they are pronounced "Pan-YAY" and "Pa-REE."

    @R.Chung: Yes, but it means something somewhat different in French. A lot of English words originated as French words, due to that whole Norman invasion and conquest back around 1066... Pretty sure that Paris, Illinois is not pronounced "Paree", for instance.

  • Flip-Flop Hub

    Most often seen on fixed gear track (velodrome) bikes, a flip flop hub is hub that allows a cog to be attached to each side.

    This allows a rider of a fixed gear bike to effectively 'change' gears by taking the rear wheel off, flipping it around and reattaching the wheel.

    Track riders will use this to have a smaller (more teeth, fewer gear inches) warmup gear that allows them to spin at a higher cadence and a larger (fewer teeth, more gear inches) cog for racing or high speed efforts.

    Variations of flip-flop hubs might offer a freewheel in one direction and a fixed gear in the other, so a cyclist can convert the bike from a single-speed to a fixed gear bike by flipping the rear wheel around.

    The unused cog is an additional hazard. Many velodromes require unused cogs to be removed. A collision involving a bike carrying an unused cog at the 2013 North America Harcourt Bicycle Polo Championships led to an amendment of the NAH ruleset to explicitly identify exposed unused cogs as a prohibited hazard. Players are permitted to carry an unused cog if it is covered.

    For a fixed-gear road cyclist, a flip-flop hub often is used to allow one side as a fixed gear, and the other side to freewheel. This way, a tired fixie rider can switch to freewheeling (possibly with a different ratio) and get home.

    More information: http://en.wikipedia.org/wiki/Flip-flop_hub

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Content dated before 7/24/2021 11:53 AM