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I thought this was a simple question but apparently there is some confusion - and it's good to have a basic question to refer people to.

How many "links" are in these short bits of chain:

Image A (the original image for this question):

enter image description here


Image B:

Some people thought the bit of chain was too short and was missing a set of rollers, or wasn't in a loop. Here's a longer length of chain -- exactly twice as long as Image A, in fact.

enter image description here

In your responses, try to make it clear whether you're referring to Image A or Image B.

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The question of how I count links is almost irrelevant, there's an industry standard way. So the question becomes "do I count links the right way". – Móż Feb 16 at 21:42
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Yeah, if you look at any of the chain manufacturer pages they say "114 links" or whatever, and it's unlikely they're selling chain in 114 x 2.5cm = more than 2m chunks. If you think about it in terms of chain pitch it might be easier - most bikes use 1/2" pitch, Shitmano for a while sold 10mm pitch, and in both cases they're talking about the gap between pins (or teeth on the matching sprockets). – Móż Feb 16 at 23:03
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F.Y.I. motorcycle chains count each pin as a link so for example a standard chain length for a motorcycle (street bike) is 120 links (5/8" pitch typically) and then it can be shortened to some even length such as 118, 116, 114.... The easy answer to this question is the # of links of the chain can be determined by counting each pin. Therefore a 120 link bike chain (with 1/2" pitch) will be 60" (which is 5 feet) long. – David Feb 18 at 3:08
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On my motorcycle, I just used the master link as a reference point then just spun the rear tire so I could count up the links. I imagine a similar thing can be done with a bicycle. You could even mark one pin with a sharpie marker for easy reference. Oh and RoboKaren, if my answer helped you, why no upvote on it? – David Feb 18 at 18:24
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I suspect the Law Of Bigger Numbers applied to sales means that chains that could be called 61 "full links" (an inner and outer pair) will be described as "112 links" purely because your packaging has "twice as many" even though each link is half as long. – Criggie Feb 19 at 2:34

Each set of "inner plates" is a link. Each set of "outer plates" is a "link."

In the photo below you can see two whole links.

enter image description here

Thus to answer the question, Image A in the question above has 4 links. Image B has 8 links.

When you buy this box of chain and it has 120 links and is standard 1/2" pitch, you should expect to get 60 inner links, 60 outer links, for a total of 120 links and it should measure 60" long:

Sram PC1071 - 120 Links

Another way of thinking about links is that a "link" as a "place where a tooth goes" - thus if a chain wrapped completely around a 44 tooth chainring - it would have 44 links -- with 22 outer-plate-links and 22 inner-plate-links.


Another way to analogize is with a standard chain:

enter image description here

Everyone would agree that the standard chain image above has six links - each link creating one "hole".


Please note that there is a small but vocal group of people (including Sheldon Brown) who count a "complete link" as "one inner and one outer half-link". Counting "complete" links has the effect of halving the number of links (thus Image A would have 2 complete links, Image B would have 4 complete links, and that five foot length of SRAM chain would have 60 complete links).
Counting "complete" and "half" links as Sheldon does is non-standard at least as far as the industry is concerned. If someone starts talking about "complete" and "half" links when talking about chain length, you should clarify with them what they are talking about as you may end up with half or double the number of links you might otherwise expect.

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Comments are not for extended discussion; this conversation has been moved to chat; additional comments no longer relevant to the edited post have also been deleted. – Gary.Ray Feb 17 at 2:11

But is is not as easy as counting links on an open chain.

The links must connect. With inner and outer you must have an equal number of inner and outer. The total must be even.

Let's say one link was removed from that chain. You would have to remove another to make it two links to connect and at two folded back on itself and I am not sure you could even call it a two link chain.

And then there is the connector thing. Connector is typically outer so you want the raw chain to end on inner both ends and you need to add one for the connector. Some times on a new chain the connector is on the chain and some times it is packaged separately. You have pin type one time connectors and reusable connector links.

You can use a 1/2 link connector to get an odd number of links. 1/2 link is used by the wider SS and fixie where you may need a more exact length. I don't think it is used in the narrow chains designed for derailleur.
1/2 link

enter image description here HL is also a style of chain but it is pretty much limited to SS, fixie, and BMX as far as I know.

Below is a SRAM with a reusable PowerLock on the left. The picture is 14 links. This chain is packaged as 114 links. You will typically cut the chain down and save the spare links for repair. Rather than count I just lay the old chain down next to the new. There is going to be some stretch so you may need to adjust to match up links (or pins/rollers). enter image description here

It is not like you go the shop and buy a specific size so I have never found a need to know the number of lengths in my chain. 114 and 116 seem to be common packaging. If you have a touring with a long chain stay or tandem then you would have some custom length chains. I suspect they just buy multiple packages and some extra connectors. You can buy spools of raw chain.

Every manufacturer seems to count chain length the same in chain packages. Here is a safe definition if you want to remove the possible confusion of plate, half, or full.

On the connected (or a configuration that will connect) chain count the number of rollers

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Not really important for most of us, but its worth noting with the new Wide/Narrow chainrings a 1/2 link cannot be used. – mattnz Feb 17 at 0:30
    
@mattnz That would really mess with the narrow wide harmony – Paparazzi Feb 17 at 1:30
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This does not answer the question of how many links there are in Image A (the original image) -- or amended, Image B. – RoboKaren Feb 17 at 2:15
    
@RoboKaren So, is this a poll? First, is not even a valid chain. – Paparazzi Feb 17 at 6:02
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When you have an odd bike, like a recumbent or a tandem, you may need to buy a chain where you have to ask for the number of links you need, having counted yourself. – Willeke Feb 20 at 18:03

Count the number of pins/rollers that would be present if you closed the chain, in this case Image A would be classified as having four "links" - answer (c), but really (e) because I don't think description quite matches the counting procedure. This is why I always hated multiple choice!!!

By the way - I am not clear on what you imply counting inner and outer "links" - inner and outer plates are involved in each junction/link.

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Sorry, fixed my question, I meant plates not links. Thx. – RoboKaren Feb 16 at 19:33
    
@RoboKaren - I am still not clear on your description, there are 4 inner and 4 outer plates in the example. "Count both the number of inner and outer plates" would give you 8! – Rider_X Feb 16 at 19:35
    
Ah, that was what I was trying to avoid - both tautology and confusion. Maybe "set of plates" would be clearer? – RoboKaren Feb 16 at 19:36
    
Got rid of multiple choice. :-) – RoboKaren Feb 16 at 19:42
    
Getting there @RoboKaren but not any clearer for me, set of plates could still be mis-interpreted because you don't get an inner plate without a corresponding outer plate in a 'regular' chain that's complete – Bent Spoke Cycle Repair Feb 17 at 17:20

I didn't really see this point of view yet, so I'll add it.

The key here is in the word itself. A link is not the flat bit of metal with two holes for pins, it is the "link" between two of these pieces. In other words, a 120 link chain has 120 connections between bits of metal. Counting the pins works, as does counting the holes between pins. This means that the open chain in image A in the question only has three links, while the closed chain in image B has eight.

However, general parlance does not always follow this. If you take a single loop from a typical chain, you might call that a "chain link", even though there is no actual "link". So this might be a bit of etymology more than anything else.

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Uh, count the number of rollers is link in bold print in my answer – Paparazzi Feb 22 at 3:38
    
And what is a roller supposed to be? Sounds like some sort of wheel to me, but chains have no wheels. Do you mean pin? – FighterJet Feb 22 at 4:06
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Uh, roller chain en.wikipedia.org/wiki/Bicycle_chain If those round contact points did not roll it would be very inefficient and things would wear out rapidly. – Paparazzi Feb 22 at 6:24
    
I get that now, but you're missing the point of my answer, which has to do with the actual meaning of the work link. – FighterJet Feb 22 at 16:26
    
And you are missing my point. A roller also removers the possible confusion of the word link from the count. You stated you had not seen the point of view yet. – Paparazzi Feb 22 at 16:33

I think perhaps there is some confusion in the term "link." Here are a couple of definitions that seem to be in use:

  1. A place where two things connect
  2. An independent section of chain
  3. The smallest section of chain that can be removed or added to an existing chain and the chain could still be rejoined.

Under the both the first and second definitions, chain A in your example has four links and chain B has eight links.

The venerable Sheldon Brown seems to subscribe to the third definition. He refers to a single set of inner or outer plates as a half link. A set of inner and outer plates constitutes a full link. This is because (barring non-standard equipment like half link connectors) it is impossible to join two ends of the chain if they both consist of inner or outer plates. You must have inner plates on one end and outer plates on the other. By this definition, chain A in your image has two full links or four half links and chain B has four full links and eight half links.

Personally, I prefer the third definition because it is the smallest functional piece of chain.

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