You need a chain tool and five minutes
Taking a bicycle chain apart means breaking the chain at one link so you can remove it, clean it, or replace it. You do this with a chain tool — a small metal device that pushes the pin out of a link. Most chains break at any link, though some modern chains have a special master link that comes apart by hand. A basic chain tool costs $8 to $15 and works on nearly every chain you will encounter.
The process itself is straightforward: position the chain in the tool, align the pin, turn the handle, and push the pin out until the chain separates. The whole job takes about five minutes once you have the right tool. The hardest part is not pushing the pin all the way out — you want to push it just far enough that the chain comes apart, but not so far that the pin falls out and gets lost.
Key Takeaways
- A chain tool is the only tool you need, and it costs less than $15 at any bike shop or online retailer.
- Most chains break at any link, but some bikes have a master link that you can open by hand without a tool.
- Push the pin out slowly and stop as soon as the chain separates — do not push it all the way through.
- Mark which direction the chain was facing before you take it apart so you can put it back on the same way.
Check what kind of chain you have
Before you reach for a chain tool, look at your chain closely. Some modern chains have a master link — a special link that looks slightly different from the others, usually with a small clip or collar holding it together. If your chain has one, you can open it by hand or with pliers, and you do not need a chain tool at all.
Most chains do not have a master link. These are standard chains, and they break at any link using a chain tool. Look at the side of the chain: you will see small metal pins running through the links. Any of those pins can be pushed out to separate the chain. If you are not sure whether your chain has a master link, spin the chain slowly and look for a link that looks different — it will usually have a slightly raised or colored appearance.
Get the right chain tool for your chain width
Chain tools come in different sizes because chains come in different widths. A single-speed chain (found on fixed-gear bikes, cruisers, and some older bikes) is wider than a multi-speed chain (found on bikes with derailleurs). Most chain tools work on both, but some budget tools only fit one or the other.
When you buy a chain tool, check the package to see what chain widths it handles. A tool that says "6, 7, 8, 9, 10, 11, 12-speed" will work on almost any chain you own. If you already have a chain tool at home, test it on your chain before you start — the chain should slide into the tool's slot without forcing it. If it does not fit, you need a different tool.
Position the chain in the tool and align the pin
Lay the chain flat on a work surface or hold it in your non-dominant hand. Open the chain tool and slide the chain into the slot so that one of the pins lines up directly with the tool's center hole. The pin should be pointing straight at you. Close the tool's clamp gently so the chain does not move, but do not tighten it yet.
Look through the small window or opening on the tool to make sure the pin is centered. If it is off to one side, open the clamp, shift the chain slightly, and close it again. Getting this right the first time saves you from pushing the pin at an angle, which can damage the link or bend the pin. Once the pin is centered, you are ready to turn the handle.
Push the pin out slowly until the chain separates
Turn the handle of the chain tool clockwise (or in the direction the tool is designed for) slowly and steadily. You will feel resistance as the pin starts to move. Keep turning until the pin pushes out far enough that the chain link loosens and you can pull the two ends apart by hand. This usually happens when the pin is about halfway out.
Stop turning as soon as the chain separates. Do not push the pin all the way through — if the pin falls out completely, it is straightforward to lose, and you will have a harder time putting the chain back together. Once the chain is loose, remove it from the tool and set the tool aside. The pin will still be partially in the link, which is fine. You can now clean the chain, inspect it, or remove it completely from the bike.
Put the chain back together if you are reusing it
If you took the chain apart to clean it or to remove it temporarily, you will need to push the pin back in to rejoin the chain. Slide the two ends of the chain back together so the pin lines up with the hole in the other link. Place the chain back in the tool, center the pin, and turn the handle in the opposite direction (counterclockwise) to push the pin back in.
Push the pin in until it is flush with the link — you should not see it sticking out on either side. Turn the handle a little past flush to make sure the pin is seated firmly. Then remove the chain from the tool and flex the link gently by hand to make sure it moves freely. If the link feels stiff, put the chain back in the tool and push the pin in a tiny bit more. A stiff link will wear out faster and can cause shifting problems.
What to do if the pin breaks or gets stuck
If the pin breaks while you are pushing it out, the chain is no longer usable — you will need to replace it. This usually happens if you push the pin at an angle or if the chain is very old and brittle. To avoid this, always center the pin in the tool before you turn the handle, and turn slowly so you can feel if something is wrong.
If the pin gets stuck and will not move, stop turning the handle when ready. Forcing it can break the pin or damage the tool. Instead, back the handle up slightly to release pressure, check that the pin is centered, and try again with slow, steady turns. If it still will not move, the chain may be too dirty or corroded. Spray the pin with penetrating oil (like WD-40), wait a few minutes, and try again.
Frequently Asked Questions
Can I take a chain apart without a chain tool?
Not easily. You could try to tap a pin out with a hammer and punch, but you risk bending the pin or damaging the link. A chain tool is designed to push the pin straight and evenly, and it costs less than $15. If your chain has a master link, you can open it by hand or with pliers.
Will taking the chain apart damage it?
No, if you do it correctly. Pushing the pin out and back in does not harm the chain. The only risk is if you push the pin all the way out and lose it, or if you push it at an angle and bend it. Take your time, center the pin, and turn the handle slowly.
How do I know which way the chain was facing?
Mark the chain with a piece of tape or a marker before you take it apart. Most chains work the same way in either direction, but some modern chains are directional and have an arrow stamped on the links. If your chain has an arrow, make sure it points in the same direction when you put it back on.
What if I lose the pin when I take the chain apart?
You will need a new chain or a replacement pin. Some chain tools come with spare pins, and you can also buy them separately at a bike shop. If you cannot find a replacement pin, the easiest fix is to buy a new chain — they are inexpensive and come with all the pins you need.
Can I use the same chain tool on different bikes?
Yes, as long as the tool fits your chain width. A universal chain tool that handles 6 through 12-speed chains will work on almost any bike you own. Keep the tool in your repair kit so you have it when you need it.