What tools are needed? How to shorten a bicycle chain using a wringer

The chain is a key element of the transmission unit of a bicycle. Consistently passing through the teeth of the drive stars, it transmits torque to the rear wheel, thanks to which the bicycle moves. During movement, the chain mechanism is subjected to dynamic loads, which eventually leads to its wear.

On singlespeed, as a rule, the chain is designed for its entire service life: when moving along the stars, it runs smoothly and straight, without deviations. The situation is more complicated with chains on multi-speed bicycles: there is no right angle between the front and rear sprockets, which is why it is always located at an angle relative to the frame. The impact on the chain mechanism increases several times compared to parallel transmission, which leads to periodic wear. To avoid damage to the entire transmission unit caused by chain wear, it must be replaced in a timely manner.

Not only “high-speed” chains require removal; quite often they are also removed from single-speed bikes for periodic repairs or cleaning. We will tell you how to remove a chain from a bicycle and put it back in this article.

Symptoms of a problem

First of all, you should pay attention to chain malfunctions on multi-speed bikes. Traditionally, riding time is determined by mileage, but these values are too approximate, because everything depends on the conditions of cycling: the quality of the roads, the selection of gears, speed, the load on the pedals and, accordingly, on the front sprockets.

The first signs of a bicycle chain failure are inaccurate gear shifting and suspicious sounds (provided that the chain has not lost its lubrication). The following method will certainly help you determine the malfunction: bend it away from the largest sprocket and look at the number of free teeth. If the chain moves freely from three or more teeth, replacement is required urgently. Two teeth “warn” that wear is just around the corner, but you can still ride.

Using the same method, you can see if the chain is loose on a single-speed bicycle: bend it away from the front sprocket and look at the number of teeth.

Determination of the degree of attenuation

Another way to determine wear is to measure the length:

304.8 mm is the optimal chain length.
306.5 – 307.5 – average wear, suitability for repair. You can still drive.
308 mm – high degree of wear of both chain and sprockets.
More than 308 mm – damage to the entire transmission.

Measuring elongation requires removing the chain completely from the bike.

Lock and solid chains

The locking chain is equipped with a special clamping device. It is not difficult to unhook and put it on - you just need to disconnect the lock. To find it, carefully examine the chain on both sides and find a split link. In principle, it will not be difficult to find it on a clean chain: there is a plier on top that fixes the link and does not allow it to move apart. Also, the manufacturer's inscription is usually stamped on the lock link. If you can’t find the lock for a long time, then either the chain is dirty, or it is lockless, or solid.

Bicycle chain with lock

You can’t just disconnect a bicycle chain without a lock: all the links on it look the same, however, they are also interlocked. This causes great inconvenience during cleaning; for example, it is necessary to carry out “general cleaning” in a solvent. In the case of the keyhole, everything is simple - steal it and put it in kerosene. A solid bicycle chain, even removed from the sprockets, will remain hanging on the frame.

In terms of removal, a chain with a lock is certainly more convenient than its counterpart. However, for some reason the fastening may become loose: the pincer may fly off, and the link itself may come loose. On bicycle chains without such locks weak points no, and if it is torn, then the matter is solely in its quality.

Opening the lock and squeezing the link axis

Opening the lock is quite simple: use a screwdriver or other object (for example, a knitting needle) to pry up the pincer clamp. The main thing here is not to damage it, and even better, not to lose it, otherwise you won’t be able to fix the chain later. Next, we uncouple the entire link. That’s it, you can remove the chain and do whatever you want with it: clean it, throw it away or shorten it. However, we'll talk about this a little later.

Lock in disassembled condition

You can disconnect a continuous chain only with a special tool - a squeezer. With its help, you can easily disassemble the link without damage. The procedure is simple, but there is no need to rush:

First, select a link for disassembly.
We insert the chain into the position of pressing out and pressing in the pin (link axis).
We tighten the screw with a handle and pull out the axle. The direction of extrusion is towards the squeeze screw, that is, towards yourself.

You should not remove the pin completely, as it will not be easy to return it to its place later.

Hall chain release device

Squeezing loosens the axle a little, so when disengaging again, you should select a different link.
Pressing the axle into a link is carried out in the opposite order: connect adjacent links and press the pin with a screw.

Elimination of defects

A common type of wear is sagging of the chain when its length increases relative to the original. Previously, critical values of the length of a bicycle chain were considered at which it cannot be used. Everything is true, but the chain does not have to be thrown away immediately, but can be repaired. Under prolonged loads, the axles become loose, which causes longitudinal and transverse expansion. It is impossible to eliminate the transverse one, but it is quite possible to tinker with the longitudinal one.

The extra links must be removed in such a way that the chain runs smoothly and without tension along the large sprocket. Using a squeezer, excess links are removed, and the axle shafts are completely pulled out from the elements being removed. The main thing here is not to make a mistake and not pull out too many links.

If you have to drive with a stretched chain, then in order to prevent it from falling off, you can install so-called parts that prevent the chain from flying off when driving. There are several types of such devices:

Roller with two locks.
With wide casters.
Frame (or rollerless).

This is what dampers look like on a bike

Using dampers as protection is, of course, good, but it would be better to think about changing the chain.

Installing a chain on a bicycle

To install a chain on a singlespeed, you just need to hang it on both sprockets, press in a pin or snap the lock. With high-speed bikes it will be a little more difficult:

Fix the derailleurs on the small chainrings.
Taking into account the location of the tension rollers, put the chain on the sprockets.
Combine the links.
Clamp the chain and press in the axle. If the bicycle chain has a lock, we do without squeezing it.

After the installation is completed, you need to check the chain movement: spin the pedals several times. If there is no sagging or difficulty during torsion, then the chain has the optimal length and is installed correctly.

Every owner of a two-wheeled horse can cope with the removal and installation of a bicycle chain. A simple and simple procedure will not take much time, but it will be a great help on future trips!

If you ride a bicycle for many kilometers, the spare parts will sooner or later wear out. After a long mileage, the bicycle chain will “stretch” and will need to be replaced.
Technically the chain does not stretch, but the pins that connect the links wear out, increasing the length of the chain.

Stretched chain accelerates the wear of the cassette and chain rings on the sprocket, so get a new chain when the stretching is already noticeable - good idea. It is recommended to replace the chain every 1000-1500 kilometers. By the way, replacing a chain is much cheaper than replacing cassettes or chain rings on a sprocket.

The chain repair and shortening information below will be very helpful.

Bicycle chain parts and necessary tools

Chain wear indicator: A typical chain wear indicator hooks onto a pin in the chain while the other end is inserted between two pins or rollers. The numbers on the tool will show how worn the chain is and whether it is time to change it.

New chain: The type of chain depends on the number of speeds of the bike. So, for example, if the bike is 9-speed, you need to buy a 9-speed chain. More advanced chains include a special coating that will delay the appearance of rust, or they are already made of stainless steel.

Replacing pins or connecting link: New chains immediately come with a new pin or special link called a connecting link that connects the 2 ends of the chain together.

If you are repairing an existing chain, you will need to buy replacement pins or connecting links separately - they must be compatible with the chain speed and brand.

Squeeze: If you have a standard link chain, you will need a compatible puller that will allow you to easily remove the old pin and install the new one when disconnecting and joining the chain.

Pliers: If you have a chain that connects to a connecting link, you will need pliers to make the process of disconnecting and connecting the connecting link easier.

How to check a bicycle chain

To check the chain for significant stretch, use. Hook one end onto a roller or pin in the chain. The other end will either go to the drive wheel itself, or you can place it in the gap between the two rollers. If it falls out of this gap, the chain is so stretched that it needs to be replaced.

The chain wear indicator has numbers that indicate how worn the chain is. A value between 0.5 and 0.75 indicates that the chain needs to be replaced. A value of 0.75 or higher means that it is necessary not only to replace it, but also to check the condition of the cassette and drive sprockets, since stretching the chain could cause significant damage to the cassette and drive sprockets.

You can check the chain in another way - measure the chain with a ruler or tape measure. On an unworn or new chain, 12 full links (measured from pin to pin) should equal 12 inches (30.48 cm). If the 12 links are 31 cm or longer in length, the chain needs to be replaced.

How to remove a chain from a bicycle

To remove the chain from the bicycle, you will need to disconnect it (break it). There are several ways to do this, depending on whether the chain has a connecting link or not.

Before you begin, move the chain to the smallest sprocket and smallest cog.

It will be even better if you remove the chain from the front sprocket or remove the rear wheel from the bike. Both of these methods will remove tension from the chain.

If you have a standard chain without a connecting link: Install the squeezer so that the squeezer pin aligns with the pin in the chain. Turn the release handle until you pull the pin out far enough to break the chain.

If you have a chain with a connecting link: To find a connecting link, look for a link that is noticeably different from the others.

This is the place where you can break the chain.

The connecting link has a pin on one side inserted into a notch on the other side.

Using pliers, squeeze the connecting link on both sides until it opens.

How to determine the length of the new chain?

Usually the new chain is too long, so it will have to be shortened by removing links. There are several ways to do this. The easiest and best way to determine the length of a new chain– attach it to the old chain. Then you just need to shorten it to match the old one (to be sure, you should count the number of links).

Another variant. Thread the chain through the front derailer and drape it over the large sprocket at the front and over the large cog at the rear. Do not run the chain through the rear derailleur yet. Connect the two ends of the chain tightly. If the chain connects and there are still 2 whole links left on the overlap (the half of the link will still remain at the end - the place where you connect the chain), the chain length is correct.

Note: Many full suspension mountain bikes use a design that moves the rear axle further away from the bottom bracket while the bike is riding, through the suspension; it is called " chain growth" To accommodate the chain growth, you will need to compress the rear suspension a lot when using the method above.

Before removing unnecessary links, make sure that the two ends of the chain will connect. The circuit can only connect if outer side link will connect to inside connecting link. Then disconnect the remaining links.

Bicycle Chain Installation

It's time to thread the chain through the rear derailleur and connect it. Pay attention and make sure the chain fits exactly through the drive wheel on the rear derailleur.

Using pins: If the chain does not have a connecting link, then use a squeezer to connect the chain to the pin that is already in the new chain.
If you are repairing an old chain, always use a new pin instead of the old one. The new pin must be compatible with the chain, its speed and brand. The new pin must be inserted halfway using a squeezer, then pulled out on the other side using pliers.

Using connecting links: If you are connecting a chain with a connecting link, place each half of it on each end of the chain, connect the ends of the chain, assemble the connecting link with a tool to put it in place.

It is also possible to connect the connecting link without tools. Connect it and pull the chain in different directions to lock the connecting link as much as possible. Then loosen the derailer clutch, if equipped, and rotate the pedals so that the connecting link is at the top of the drive chain. Using the brakes, step firmly on one pedal, tension will be applied to the chain and it will snap into place.

How to replace a chain on a bicycle - video

It happens that you need to remove a bicycle chain - for example, to clean it, replace it or adjust the length (the latter is done if your new cassette has a different number of teeth, and you need to change the length of the chain accordingly by adding or removing a certain number of links) .

How to remove a chain with a lock

Inspect the chain: if you find a link that is different from all the others, then you are lucky - you have a chain with a lock. In order to separate it, move the pins (pins, axles) on each half-link (cheek). The circuit will open. The whole operation will take literally a minute. You don't need any special equipment: if you suddenly can't move the pins by hand, use pliers. Assembly is also done without any tricks, in reverse order.

How to remove a chain without a lock

If you have a chain without a lock, then you will need a special tool - a chain squeezer. It is inexpensive and takes up little space, so we recommend that you always carry it with you, along with a set of hexagons and a repair kit for cameras. Anything can happen on the road - if the chain suddenly breaks, you can easily remove the damaged links using a squeezer and connect the chain again.

How to remove a chain without squeezing? And is it worth doing?

How to remove a chain without squeezing is a pressing question. But no matter how often it is asked, it is better to remember one life rule. For good repair and maintenance, it is better to use a specialized tool! In this case it is chain squeezing.

There are two types of squeezers, most have two seats. One of them is for assembling and disassembling the chain, the second is for adjusting the position of the axle in the chain link bushing. If your squeeze is just like this, with two seats, then insert the chain link so that it is on the side closest to the adjusting screw. If you place the chain in the wrong place, you may accidentally break off the partitions between the squeeze seats during operation or crush the cheeks of the link.

Let's assume that the chain was laid correctly. Now carefully rotate the handle. You may have to apply significant force, so try to work carefully so that the link in the squeezer does not become distorted, otherwise it may be damaged. Make sure that the tip of the squeezer presses exactly on the pin. There is no need to turn the screw quickly; you should stop at the moment when the pin is squeezed out of the entire link, but remains on the far cheek. If you push it all the way out, believe me, it will be very difficult for you to put it back in. Also be careful not to accidentally knock the pin out of the cheek: this could cause it to roll away in an unknown direction and get lost.

When assembling, you will not need anything other than the same squeeze. I remind you again: be careful, don’t get carried away, so as not to squeeze the pin out of the link.

Two important notes:

If your chain is equipped with a lock, you should not disassemble it by squeezing it.
If you have to disassemble the same chain many times, then choose a new link each time: if you squeeze out the same pin over and over again, this will deteriorate the strength of the chain

After using a bicycle for a long time without maintenance, the chain often begins to sag. How to shorten a bicycle chain at home? What is required to determine it correct length? We will look for answers to these and other questions in the presented material.

What factors affect the elongation of a bicycle chain?

To the wear of the axes, the so-called pins, bicycle chain brings up a number of points. Firstly, deposits in the form of old oil accumulate between structural elements, onto which dust and small contaminants stick. Additionally, stretching can put undue stress on the chain when cycling up steep inclines. Another reason is the end of the chain’s service life, the destruction of its elements as a result of impacts and metal corrosion. To avoid discomfort while operating the bike, you need to understand

How to determine the optimal length?

Before you figure out whether you can shorten the chain on a bicycle with your own hands, you need to find out how long it should be for comfortable movement. To understand this issue, it is enough to throw the chain onto the largest sprockets in both the rear and front chassis of the bike. Next, you need to open one of the links. Finally, tighten the chain as much as possible. It is enough to add a couple of centimeters to the resulting length so that the chain is not under excessive strain while driving.

Preparation for dismantling

To make it easier to work with the chain, it is worth cleaning it first. The simplest way- wipe it with a regular piece of material soaked in kerosene. You can also use a special remover, in particular AB-80 or WD-40 liquid.

Tools

How to shorten the chain on a speed bike or mountain bike? There are several tools you can use to separate the links. First of all, you should pay attention to the special squeeze. The latter is a simple device that resembles a manual stand with a rod that applies pressure to the axes (pins) of the links. You can buy such a tool at any point of sale. sports equipment. Its purchase will cost from 500 to 1000 rubles.

If it is not possible to buy a squeeze, then you will have to use improvised means. We are talking here about a hammer and a metal rod, which will serve as a punch for removing the axes of the links. You will also need a couple of nuts that will fit under the chain links.

How to shorten a bicycle chain using a wringer?

To do the job using a special tool, you need to perform the following sequence of actions:

Place the squeezer in a position where its rod is centered on the axis of the chain link.
Perform rotational movements with the tool until the axle is almost completely out of the link.
Disconnect the circuit and, if necessary, perform similar operations with its remaining sections.
Remove unnecessary links and connect the structure.

Having figured out how to shorten a chain on a bicycle, you need to figure out how to connect it. A narrow half-link must be inserted between the cheeks of a wide one. The axle should then fit completely into the hub hole. Next, it is necessary to evaluate the mobility of the links. If it is insufficient at the joint, the hinge can be developed using pliers.

How to shorten a chain on a bicycle without squeezing?

The absence of a specialized tool designed to separate chain links is not a critical point. As mentioned above, an alternative to squeezing can be a metal pin, nail, etc. Also here you will need a hammer, with which the axles will be knocked out of the links.

With this approach to business, the main thing is to be careful. After all, they are too sloppy strong blows may lead to deformation of the link plates. To prevent this from happening, regular nuts must be placed under the chain elements in advance.

Those who are trying to shorten a bicycle chain for the first time without using a special squeezer are recommended to practice beforehand. For these purposes, it is worth using an old chain or separate, unnecessary links. This kind of work requires some skill. Therefore, before influencing a working chain with a hammer and a punch, you need to perform the above steps several times and evaluate the result of your own work.

Finally

So we figured out how to shorten a bicycle chain. As you can see, you can cope with such a task not only with the help of a special squeeze. To get the job done, sometimes it is enough to use available tools that can be found in every home.

What could be better than a day spent cycling in the countryside! However, the pleasure can be overshadowed by an unexpected chain breakdown. If domestic bicycles mostly consist of detachable chain sections, the locks between which can be separated without much difficulty, then the chains are often one-piece. Today we will talk about how to remove the chain and what devices exist for this.

When is the chain removed from a bicycle?

Experienced cyclists remove the chain regularly. For example, in the case when replacing the system or just the cassette entails a change in the number of teeth, the chain will have to be shortened by removing teeth, or lengthened by adding additional ones. In addition, the chain is removed in order to:

wash;
boil in grease;
replace (if repair is no longer possible).

Instructions for replacing a chain with a squeezer yourself

Removing the chain by squeezing.

Usually, to remove the chain from the bike, an auxiliary tool is used - a squeezer. It makes it easy to remove even a permanent chain. The sequence of work is as follows:

Decide on the section of the chain to be disassembled. In case of repeated disassembly of the chain, it is preferable to take a section of the chain that cannot be repaired.
Insert the chain into the squeeze so that the pin is opposite the clamping axis.
Secure the chain with a knurled screw.
Turn the handle, squeezing the pin out.
Remove unnecessary links using a squeezer, pressing out the entire pin.
Connect the chain links. In this case, the pin located in the cheek should look outward towards you. First you need to run the chain through the rear and front derailleurs. Then place the chain links one on top of the other so that the pin aligns with the bushing.
Unclench the “cheeks” with pliers. Once the ends of the chain are in place, the pin coming out will prevent the links from coming apart.
Insert the squeeze into the link so that the axes of the pin and rod match perfectly, and rotate the funnel, pressing the pin into the hole.
Check the symmetry of the position of the pin and the “cheeks” of the links. Adjust their position if necessary.
Check the links for mobility relative to each other. If necessary, increase the mobility with pliers.

Important! On a high-speed bicycle, the chain is installed along the switch rollers at the rear in accordance with the pulling diagram. To be able to replace the chain multiple times in the future, it is best to lock the chain.

Sequence of actions for removing a chain from a bicycle without squeezing it yourself

The squeezer is a useful device. However, it is not always at hand. What to do then? The prospect of being left in the middle of pristine nature somewhere many kilometers from the city does not look attractive. You can remove the chain from the bike without squeezing it. Doing this on your own will not be easy, but it is quite possible. Let us consider in detail the options for disassembling a chain with and without a lock.

Model with lock

How to check if a chain has a lock? As easy as pie! A quick inspection to see if the chain has a link that is different from its neighbors. This is the castle. You can disconnect it by moving the pins on each of the links with your hands or pliers. To assemble the chain, you need to do the same steps in reverse order.

Model without lock

In this case, it will be difficult without squeezing. And the result will be unpredictable. But, if there are no other options, choose the lesser of 2 evils. So, we remove the chain without a lock from the bicycle using improvised means in this order.

Screw an ordinary vice to the table.
Secure the chain in a vice by placing a nut on one side, the hole of which corresponds to the pin.
Attach a small screw with a head on the other side.
While holding the vise, push the pin into the nut hole with the ball.

Important! In order to open the circuit, freeing one side is not enough. You need to move the link and remove the chain or add another ball and continue trying.

Summing up, we can confidently say that the squeeze is an indispensable thing on the road for every cyclist. And if a broken chain with a lock can still be removed from the bicycle without this device, then as for a chain without a lock, it will be difficult to do without it. However, in case of form major circumstances, you can use the instructions given above.

Chain length:

Chain length is a parameter that many people overlook when assembling a bicycle from scratch from a kit of components, or when replacing a worn chain. In fact, it is also worth remembering that many new bicycles sold in stores due to oversight or manufacturer error may have too long a chain, which will inevitably worsen shifting accuracy. In addition, she will also jump off stars more often on technical terrain, roots and rocks. But if a long chain can simply give you an unpleasant surprise several times during your trip, then the consequences of installing an overly short chain can be catastrophic. At best, you simply won't be able to switch to big stars of the system And cassette from high tension. At worst, the rear derailleur may come off and break (at the same time knocking out several spokes from rear wheel), the chain itself will break. It's safe to say that an incorrectly selected bicycle chain length is a direct path to a quick repair.

Rear derailleur type:

The rear derailleur on your bike plays a huge role in adjusting chain length and tension. The derailleur tab, moving back, maintains enough tension when you use a small chainring in the cassette, but it also compensates. However, it can also move forward when you shift to larger chainrings to climb a hill. Respectively rear derailleurs are issued in 3 possible options: with short, medium and long leg/frame (depending on your preferences and the capabilities of the bike). The basic principle when choosing a new derailleur is: the wider the gear range, the longer the claw should be. If we consider the classic layout bicycle transmission with 3 stars in the system, then a long foot would be most appropriate. If we are talking about models with one star in the system, then a short claw is quite suitable. For example, if you want to use a short rear derailleur on a bike with a long range of gears, then you will also need to install an overlong chain (which will compensate for the lack of derailleur length). And, unfortunately, there is no middle ground here. An incorrectly sized rear derailleur will prevent you from getting the correct chain length and avoiding damage.

A chain that is too long will often fly off and cause shifting problems, while a chain that is too short will rip your rear derailleur off. Are you eager to check the chain length on your bike?

Helpful Tips:

It is important to remember that you need to determine the length of the chain on a double-weight bike (a bicycle with front and rear shock absorbers) at the moment when the rear shock absorber is pressed through its entire stroke (i.e. under load). In this case, the chain must be installed on the largest diameter sprockets in the cassette and system.

On modern bicycles with a 20-speed transmission (2 sprockets in the system and 10 in the cassette), you can use a combination of the largest diameter sprockets at the front and rear when driving. This is not recommended for bikes that have 3 stars in the system. However, when choosing the length of the chain, you still need to put it on the largest sprockets in the cassette and system - after all, you can accidentally switch to this combination while riding, and you don’t want this to lead to damage.

Some professional cyclists set the chain to the shortest possible length to minimize the possibility of it coming off even on the most difficult terrain. In this case, you must constantly ensure that you do not use a large star at the front and rear at the same time. But we do not recommend such experiments to you.

On many bikes shipped from the factory to stores and dealers in different countries, the standard chain is too long. Therefore, it is recommended to check it further, even considering that the bike is completely new, out of the box.

Length of the rear derailleur foot Sram And Shimano different. The same can be said about switches of the same series from the same manufacturer, but different model years. This means that after replacing the rear derailleur, checking the chain length is included in the list of mandatory service activities.

Features of dual suspensions

Setting the required chain length is not a difficult task, but everything becomes not so simple in the case of double suspensions. Why is this happening? Many bicycle manufacturers use suspension layouts that improve pedaling efficiency. At the same time, as the suspension is activated, the distance between the carriage and the rear wheel axle increases. This displacement can occur throughout the entire suspension travel, or only within a certain range. But this in any case means that, all other things being equal, it is necessary to install a longer chain on a double suspension than on a hardtail.

Push the suspension to full travel, because... it is in this position that you will be able to determine suitable length chains. If your bike has an air rear shock absorber, simply bleed the air through valve(looks like a “car” nipple), simultaneously compressing the suspension with its weight. With a coil shock, you will first have to remove it from the frame, remove the spring, and then put the shock back in.

Before you begin manipulating the shock absorber, you need to switch the chain to the largest sprockets in the cassette and system. For convenience, you can secure your bike in repair counter, if there is one.

If the chain length is too short, you will immediately notice this by the position of the rear derailleur tab. The photo above shows the position of the rear derailleur with the suspension fully compressed. We can say with confidence that such a chain length will, at best, cause damage to the cock and the rear derailleur itself. Accordingly, you need to add several links, or choose a longer chain.

The photo above shows the position of the rear derailleur with the correct chain length. By adding just two extra links, we saved ourselves a lot of potential problems.

Shift the chain to the smallest sprocket in the cassette and system. If you see a picture similar to the left photo, then the chain length is chosen almost perfectly. We see that the chain is sufficiently tensioned, but at the same time the necessary free play is maintained, and there is also a reserve for switching to larger sprockets. The right photo shows a chain that is too long, which, as we have already found out, can lead to serious damage to your bike, as well as regular chain jumping off the sprockets.

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“Chemistry Saturated hydrocarbons” - chemistry on the topic: “Alkanes”. Sources of saturated hydrocarbons are oil and natural gas. 5. Hydrogenation (addition of hydrogen) of alkenes. 1.Decarboxylation of sodium salts of carboxylic acids. Presentation on organic. 1. The most characteristic reactions of saturated hydrocarbons are substitution reactions.

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After using a bicycle for a long time without maintenance, the chain often begins to sag. How to shorten a bicycle chain at home? What is required to determine the correct length? We will look for answers to these and other questions in the presented material.

What factors affect the elongation of a bicycle chain?

A number of factors lead to wear of the axles, the so-called pins, of a bicycle chain. Firstly, deposits in the form of old oil accumulate between structural elements, onto which dust and small contaminants stick. Additionally, stretching can put undue stress on the chain when cycling up steep inclines. Another reason is the end of the chain’s service life, the destruction of its elements as a result of impacts and metal corrosion. To avoid discomfort while operating the bike, you need to understand

How to determine the optimal length?

Preparation for dismantling

To make it easier to work with the chain, it is worth cleaning it first. The simplest way is to wipe it with a regular piece of material soaked in kerosene. You can also use a special remover, in particular AB-80 or WD-40 liquid.

Tools

How to shorten the chain on a speed bike or mountain bike? There are several tools you can use to separate the links. First of all, you should pay attention to the special squeeze. The latter is a simple device that resembles a manual stand with a rod that applies pressure to the axes (pins) of the links. You can buy such a tool at any point that sells sports equipment. Its purchase will cost from 500 to 1000 rubles.

How to shorten a bicycle chain using a wringer?

To do the job using a special tool, you need to perform the following sequence of actions:

Place the squeezer in a position where its rod is centered on the axis of the chain link.
Perform rotational movements with the tool until the axle is almost completely out of the link.
Disconnect the circuit and, if necessary, perform similar operations with its remaining sections.
Remove unnecessary links and connect the structure.

How to shorten a chain on a bicycle without squeezing?

With this approach to business, the main thing is to be careful. After all, inaccurate, too strong blows can lead to deformation of the link plates. To prevent this from happening, regular nuts must be placed under the chain elements in advance.

Finally

In this article, we will discuss how to select chain length for a derailleur bike.

What tools are needed?

Chains for derailleur bikes must be a certain length. A chain that is too long or too short can cause problems when shifting and driving. However, the rear derailleur tab must be long enough to tighten the loose chain as it moves between different gear combinations. All this relates to the topic " general power” and is discussed below.

This article describes three ways in which you can select the required chain length. All three methods allow you to achieve this. In addition, there is no need to use all three methods, just choose one that you like and suits the situation. The first method can be denoted as USING AN ALREADY EXISTING CIRCUIT. It implies that the bicycle already has a chain installed. The second method is called: THE BIGGEST SPROCKET IS THE BIGGEST CHAIN RING, and it does not assume the presence of an old circuit. The last way is METHOD OF MATHEMATICAL CALCULATION chain length.

REAR SUSPENSION REMINDER: If the bike has a rear suspension linkage, then it is necessary to calculate the movement of the rear hub from the bottom bracket. If the rear hub moves away from the bottom bracket, the chain is in its longest position. If in doubt, check with the manufacturer for the correct chain length.

SWITCH CAPACITY: The term "Shifter Capacity" refers to its ability to lift the tab when changing gears. Some bikes have sprocket combinations that prevent the derailleur from lifting the chain tab. In this case, the gears on the bike exceed the derailleur capacity. If the derailleur capacitance does not match the bike's gear dimensions, the chain will fail the "too long" or "too short" test. It is impossible to select a chain length that would satisfy both parameters. In this case, it is better to leave the chain longer than shorter. Both methods: and method using already existing chain, and the mathematical calculation method described below will determine the safe circuit length if the switch capacitance is compromised. Perhaps, in this case, it is worth avoiding those speed combinations that lead to problems when moving on a bicycle.

Method of using an existing circuit

Before you remove the old chain, check what length of chain you need. Cut off new chain, equal in length to the old one. Shift the bike's speed so that the chain is on the smallest front sprocket and the smallest rear sprocket. Carefully inspect the area of the chain between the lower derailleur and the smallest sprocket. There should be no noticeable chain slack in this area. Also check that Bottom part the chain did not touch the pulley. It is normal for the chain to have a little slack in this position, but it should not flex too much. Excessive slack is an indication that the chain is too long.

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If the chain is too long, find the rivet that is hitting the sprocket and mark the sprocket at that location. Count two rivets towards the derailleur, lift this link and move it to the mark on the sprocket. The chain is now much shorter. Check the sag again. Repeat the action, counting two rivets, and moving the chain to the mark. The number of chain links being reduced should be (2, 4, 6, etc.). Repeat until there is no visible sagging left.

To determine if the chain is too short, move it to the largest sprocket in front and the second largest sprocket in the rear. The chain will tighten in this position. Look closely at the S-shaped section of the chain, as this is where the chain goes through the pulley. Slowly and carefully begin turning the largest rear sprocket. If the chain is too tight, it is too short. If the chain moves but there is no double bend as the chain passes the wheels of the pulley, again it is too short. You need to add two links of the new chain compared to the old one. Attention: Do not try to lengthen an old chain by adding new links.

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If the chain length passes one of the tests listed above but fails the other, then the derailleur's capability is likely to be inconsistent with the transmission. Determine the length of the chain so that it goes through the largest front sprocket to the largest rear sprocket. After this, all responsibility for shifting combinations when shifting gears will lie with the owner of the bicycle.

If you want to install a new chain, but the old one is the correct length, you can measure the new chain to the length of the old one before installation. First, remove the old chain and place it on a flat, flat surface with the rollers positioned vertically. Align the chain. Place the new chain next to the old one in the same way. Check that the ends of the two chains match (either both chains must have rivets at one end, or both chains must have no rivets). The new chain will appear shorter, so move the links of the old chain so they line up with the new chain. Match the rivets on the new chain with the rivets on the old one. Add or remove links as necessary based on the checks above and cut the chain at this point.

Method: the largest sprocket - the largest ring of the chain

An alternative method of measuring the length of a new chain is to use the largest sprockets on the bike. This is the most easy way measure the circuit without passing it through the switch. After determining the length of the chain, remove it and cut it. Then feed the circuit through the switch and connect.

Pay attention to the main link: If the chain has a main link, then it is necessary to count from it along one side of the chain. Measure the chain and cut off any excess links.

Determination of chain length by mathematical calculation

Bicycle chains are made up of inner and outer plates. The only possible way to connect them is to connect the outer plate to the inner one, so chains can be connected if there are whole links. For example, the chains of some speed bikes can have a length of 51, 52, 53 inches. The chain cannot be cut to 52-1/4", 53-1/8", or even 52-1/2".

It is possible to determine the length of the chain using the industrial railway equation, and cut it before installing it on the bike. Start by counting the number of teeth on the largest front and rear sprockets. This information is often written directly on them. The next step is to measure the distance between the center of the crank bolt and the rear axle. This will be the length of the chain, a multiple of 1/8", and convert it to the form decimal. The table below will help you with this.

1/8" = 0.125"
1/4" = 0.25"
3/8" = 0.375"
1/2" = 0.5"
5/8" = 0.625"
3/4" = 0.75"
7/8" = 0.875"

For most bicycles, a relatively simple chain length equation can be used. For bikes with larger differences in sprocket and short chain sizes, a more complex equation can be used. It is described later in the article.

Simple equation: L = 2 (C) + (F/4 + R/4 + 1)

L = Chain length in inches. Rounded integer.
C = Distance between center of crank bolt to rear axle in inches, measured in 1/8" multiples. Use the conversion table above common fraction to a decimal fraction.
F= Number of teeth on the largest front sprocket. R= Number of teeth on the largest rear sprocket.

Example: The bike has 42-32-22 front sprockets. To calculate, you need a 42 sprocket. The largest rear sprocket installed has 32 teeth. The distance between the center of the crank bolt and the rear axle is 16-3/8", which is 16.375 inches.

L = 2 (16.375) + (42/4 + 32/4 + 1)

From the example above, the equation is 32.75 + 10.5 + 8 + 1 = 52.25 inches. Chains cannot be connected at a length of 52.25 inches, so the number is rounded up to 52 inches.

According to this system, the number can be rounded to 0.5. For example, a calculated chain length of 55.5 would need to be rounded to 56 inches.

To measure a new chain, place it on a flat surface with the rollers and plates vertical. Pull both ends to align the chain. Measure it starting from either end. Remember, you can only shorten the chain by multiples of one inch. If the main link is marked on the chain, use it as a starting point for measurement.

Strict equation

An example of bicycles that require an accurate equation would be road bikes with large front sprockets (perhaps 55 teeth) and small rear sprockets (11 teeth). Also, if the bike has a very short crank bolt to rear axle distance (15 inches or less), then again a strict equation will need to be applied. Since the front and rear sprockets are different in size, the chain should diverge, representing a triangle. The chain length of the resulting triangle can be added by adding the hypotenuse. Again this applies in very exceptional cases.

As an example of applying the strict equation, let's say the chain length of a single speed bicycle is 15 inches, the front sprocket has 58 teeth and the rear has 11 teeth. The bike does not have a derailleur installed, so the length does not need to be increased by 1 inch. This inch should only be added on derailleur bikes.

Calculating the length of the chain road bike using the shortened equation, the answer is 47.25 inches. We round this result to 47 inches. Applying a strict equation, we get a result of 48.17 inches, which we round up to 48 inches. Again, the example shown does not add an inch of chain because there is no derailleur. When calculated using the simplified equation, the chain will be an inch shorter. But this is not a typical situation. Typically, even in the single speed bicycle example, if the sprocket is reduced to 55 teeth, the two equations will show the same result.

What tools are needed? How to shorten a bicycle chain using a wringer

Symptoms of a problem

Lock and solid chains

Opening the lock and squeezing the link axis

Elimination of defects

Installing a chain on a bicycle

Bicycle chain parts and necessary tools

How to check a bicycle chain

How to remove a chain from a bicycle

How to determine the length of the new chain?

Bicycle Chain Installation

How to replace a chain on a bicycle - video

What factors affect the elongation of a bicycle chain?

How to determine the optimal length?

Preparation for dismantling

Tools

How to shorten a bicycle chain using a wringer?

How to shorten a chain on a bicycle without squeezing?

Finally

When is the chain removed from a bicycle?

Instructions for replacing a chain with a squeezer yourself

Sequence of actions for removing a chain from a bicycle without squeezing it yourself

Model with lock

Model without lock

What factors affect the elongation of a bicycle chain?

How to determine the optimal length?

Preparation for dismantling

Tools

How to shorten a bicycle chain using a wringer?

How to shorten a chain on a bicycle without squeezing?

Finally

What tools are needed?

Method of using an existing circuit

Method: the largest sprocket - the largest ring of the chain

Determination of chain length by mathematical calculation

Strict equation

How to determine the optimal length of a bicycle chain - video