A method of using an existing circuit. How to determine the length of a new chain

"Alkadienes" - Conjugated 1,3-butadiene (divinyl). 7.2.2-methylbutadiene (isoprene). 12. 9. LEBEDEV Sergey Vasilievich (25.VII.1874 - 2.V.1934). Nomenclature and isomerism. Structural features, reactivity and methods for the synthesis of alkadienes. Alcadienes. 5. 10. Chemical properties. Isolated pentadiene-1,4. eight.

"Alkanes" - To reveal the patterns of distribution of n-alkanes along the profile of peaty-podzolic-gleyic soils of virgin and aerotechnogenic landscapes of the taiga zone. Assess the contribution of "even" and "odd" n-alkanes in the total pool of saturated hydrocarbons accumulation in soils. CPI - carbon preference index - ratio of odd to even alkanes.

"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. Organic presentation. 1. The most typical reactions of saturated hydrocarbons are substitution reactions.

"Alkenes" - Addition reaction schemes. Polymerization reaction. What laboratory method can be used to obtain alkenes? Sinkwine. Combustion of alkenes example: 2c2n6 + 7o2 4co2 + 6n2o. Dehalogenation. Laboratory method of obtaining. Methods for obtaining alkenes. Dehydration of alcohols. The use of ethylene. Oxidation reactions. Dehydrogenation of alkanes.

"Esters chemistry" - The mechanism of the esterification reaction. Lesson topic: Nomenclature. Physical properties of esters. 1. To study the structure of esters. 2. To get acquainted with the mechanism of the esterification reaction. Esters. Lesson objectives: The main works are devoted to organic and analytical chemistry, biochemistry and thermochemistry. He was the first to synthesize fat-like substances, ethyl alcohol, by hydration of ethylene.

"Alkane" - The longest hydrocarbon chain gives the name to the whole compound. Free rotation around the C-C bond. Kerosene. 2,3-dimethylhexane. 1700C C14 - C20. Alcan. a) Fischer-Tropsch method (synthesis from carbon monoxide). c) Electrolysis of carboxylic acid salts (Kolbe's method (1849).

There are 14 presentations in total

After using the bike for a long time without maintenance, the chain often starts to sag. How to shorten your bike chain at home? What is required to determine the correct length? Let's look for answers to these and other questions in the presented material.

What factors affect bike chain lengthening?

A number of factors lead to wear on the axles, the so-called pins, of the bicycle chain. Firstly, deposits in the form of old oil accumulate between the structural elements, on which dust and small impurities adhere. In addition, stretching can cause undue stress on the chain when climbing steep climbs on the bike. Another reason is the end of the chain's service life, the destruction of its elements as a result of impacts, metal corrosion. To avoid discomfort during the operation of the bike, you need to figure out

How to determine the optimal length?

Before figuring out whether it is possible to shorten the chain on a bicycle with your own hands, you need to find out how long it should have for comfortable movement. To understand this issue, it is enough to throw the chain over the largest sprockets, both in the area of ​​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 overstressed during 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 wash, such as AB-80 or WD-40.

Tools

How to shorten the chain by speed bike or a mountain bike? Several tools can be used to sever links. First of all, you should pay attention to the special pomace. The latter is a simple device resembling a manual bed with a rod, which exerts pressure on the axles (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 pomace, then you will have to use the means at hand. We are talking here about a hammer and a metal bar, which will serve as a punch for extracting 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 squeeze?

To do the work, resorting to the operation of a special tool, you need to perform the following sequence of actions:

1. Set the squeeze to a position in which its pin will be in the center of the chain link axis.
2. Perform rotational movements with the tool until the axle is almost completely out of the link.
3. Disconnect the chain and, if necessary, carry out similar operations with its remaining sections.
4. Remove unnecessary links and connect the structure.

Once you've figured out how to shorten your bike chain, you need to figure out how to connect it. A narrow half-link must be inserted between the wide cheeks. Then the axle should fit completely into the bore of the hub. Next, you need to assess the mobility of the links. If it is insufficient at the joint, the hinge can be worked out with pliers.

How to shorten a bicycle chain without squeezing?

The lack of a dedicated tool for separating chain links is not critical. As mentioned above, a metal pin, nail, etc. can serve as an alternative to squeezing. You will also need a hammer here, 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, sloppy, too strong blows can lead to deformation of the link plates. To prevent this from happening, ordinary nuts must be placed under the chain elements in advance.

For those who are new to shortening a bicycle chain without using a special squeeze, it is recommended to practice first. For these purposes, it is worth using an old chain or separate, unnecessary links. Such work requires a certain skill. Therefore, before acting on a serviceable chain with a hammer and a punch, you need to perform the above steps several times and evaluate the result of your own labors.

Finally

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

Chain length:

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

Rear Derailleur Type:

The rear derailleur on your bike plays a huge role in adjusting the chain length and tension. The derailleur foot moves backward to maintain sufficient tension when you use the small chainring in the cassette, but it also compensates. However, it can also move forward when you switch to large stars to overcome the rise. Respectively rear derailleurs produced in 3 possible options: with short, medium and long foot / frame (depending on your preference and the possibilities of the bike). The basic principle when choosing a new derailleur is that the wider the gear range, the longer the tab should be. If we consider the classic layout bicycle drivetrain with 3 stars in the system, then a long leg will be most appropriate there. If we are talking about models with one star in the system, then the short presser foot is fine. For example, if you want to use a short rear derailleur on a bike with a wide gear range, then you will also need to install a chain that is too long (which will compensate for the insufficient derailleur length). And, unfortunately, there is no golden mean 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 fly off a lot and cause shifting problems; too short can rip your rear derailleur off. Can't wait to check the chain length on your bike?

Helpful hints:

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

On the modern bicycles with a 20-speed transmission (2 stars in the system and 10 in the cassette), you can use a combination of the largest diameter stars in the front and rear when driving. It is not recommended to do this on bicycles with a 3-star system. However, when choosing the length of the chain, you still need to put it on the largest stars in the cassette and system - you can accidentally switch to such a combination while riding, and you don't want it to lead to a breakdown.

Some professional cyclists keep the chain as short as possible to minimize the chance of it coming off even on the most difficult terrain. In this case, you must constantly be careful not to use the large chainring at the front and rear at the same time. But we do not recommend such experiments to you.

Many bicycles sent from the factory to shops and dealers in different countries the standard chain is too long. Therefore, it is recommended to additionally check it, even considering that the bike is completely new, out of the box.

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

Features of double suspensions

Setting the required chain length is not a difficult task, but everything becomes not so easy in the case of double suspensions. Why is this happening? Many bike manufacturers use suspension arrangements that improve pedaling efficiency. In this case, as the suspension is triggered, 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 in any case, this means that a longer chain must be installed on a full suspension, other things being equal, than on a hardtail.

Squeeze the suspension all the way, because it is in this position that you will be able to determine suitable length chains. If your bike has a rear air shock, simply bleed the air through valve(it looks like a "car" nipple), in parallel compressing the suspension with its weight. In the case of a spring-loaded shock absorber, you will first have to remove it from the frame, remove the spring, and then insert the shock absorber back.

Before you begin to manipulate the shock absorber, you need to shift the chain to the largest sprockets in the cassette and system. For convenience, you can fix the bike in repair rack, if any.

If the chain length is too short, you will immediately notice it from the position of the rear derailleur foot. The photo above shows the rear derailleur position when the suspension is fully depressed. We can say with confidence that such a chain length will, at best, cause a breakdown of 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 additional links, we have 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 photo on the left, then the length of the chain is matched almost perfectly. We see that the chain is tight enough, but at the same time the necessary free play is preserved, and there is also a margin for switching to larger stars. 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 stars.