The chain is the main component of a bicycle transmission. It transmits torque to the rear wheel, passing through the drive sprockets. Thus, the bike is set in motion. As a result of the loads to which the chain is exposed during operation, it wears out.
On bicycles with the same speed, the chain usually lasts the entire service life, as it moves along the sprockets smoothly and directly. To remove this part on a speed bike is required much more often: due to the fact that there is no right angle between the front and rear sprockets. As a result of this, the load on the chain mechanism increases several times, which leads to wear.
Symptoms
First of all, you need to pay attention to chains on multi-speed bikes. Although the operating time of this element is formed from the mileage traveled, the value is very approximate, since the real time of use is determined by the nature of the ride, high-speed mode, and the quality of the roads.
Inaccurate gear changes and a strange clang are the first symptoms of a chain failure. To find out for sure, you can use the following method.
The chain bends away from the largest sprocket. If three or more teeth remain free, urgently need to remove the chain from the bicycle and replace it. The same method is suitable for single speeds.
In addition to the method described above, there is another one - measuring elongation:
- 304.8 mm - ideal chain length;
- 306.5 - 307.5 - acceptable wear, while you can ride;
- 308 mm - heavy wear of chains and sprockets;
- 308 mm or more - the transmission unit is badly damaged, the bike chain urgently needs to be replaced.
In the image below, the difference in length between the worn chain (above) and the newer (below) is clearly visible:
Bike chain with and without lock
It is no more difficult to remove the chain of a speed bike than to remove it from a regular two-wheeled "friend", since it all depends on whether the chain is equipped with a lock or not. If a part with a lock is installed on the bike, then removing it for replacement or cleaning will not be difficult. If the chain is not very dirty, the link with the lock can be found almost instantly. If the assembly could not be found, then the part is either solid or it needs to be thoroughly cleaned.
Bike chains with a lock are equipped with a special clamping mechanism. As for convenience, it is much easier to remove the chain with the lock from the bicycle than a structural element without constipation. But in fairness it’s worth saying that the clamp can loosen, and the link itself can come loose. At the same time, there is no such problem with continuous chains - if the chain is broken, then the whole problem is solely due to its quality.
Removing the bike lock
The process of assembling and disassembling the part is the same for single-speed and multi-speed bicycles. Before you remove the bicycle chain, you need to find the link with the lock. There is often the name of the manufacturer and there is a special clamp with which adjacent links are held.
Locks of various companies are not the same, but the process itself has minimal differences. It is necessary to connect adjacent axles and remove the clamp. Pry the lock with a slotted screwdriver or any other sharp object. At the same time, try not to damage or lose the clamp, otherwise the chain cannot be assembled again.
Solid chain removal
It is much more difficult to remove the chain of a bicycle without a lock. For this, a special device is useful - squeezing the chain.
Of course, you can do without it, for example, put a pin on the table and gently tap it. True, after this operation it will be incredibly difficult to push it back.
How to shoot a solid bike chain:
- Any link is selected, installed in the puller so that the axis is opposite the release axis.
- Then, slowly turning the screw, squeeze the pin. Here the bottom line is that you do not need to extrude the axis completely.
Thus, you can not only remove the chain from a high-speed bike, but also repair a regular one.
Defect correction
The most common type of wear is sagging. The critical values of the extension of the bicycle chain were analyzed above, at which its further operation is extremely undesirable. But it is not necessary to discard the chain at the slightest wear, you can try to repair it. With prolonged loads, the axles of the chain become loose, which results in longitudinal and transverse deformations. It is impossible to get rid of the last type of deformation, but you can fight the longitudinal one.
In order to get rid of the longitudinal expansion, it is enough to remove the extra links. They must be removed so that the chain moves along a large star without tension. With the help of squeezing, excess links are removed, and excess axle shafts are completely removed. It is important not to overdo it and not to pull out the excess.
If you need to go immediately, and there is no time to repair, you can use the so-called sedatives. So called devices that do not allow the chain to slide off when moving.
Chain installation
Before starting the installation, make sure that it fits the bike in length and width. If the chain is too wide or narrow, then it cannot be installed. In the case of length, everything is much simpler: just remove the extra links.
In order to install the chain on a speed bike, it is necessary to set the speed switches to the highest mark, and then lock them. When installing the bike chain, you need to correctly put it on the tensioner rollers. The chain should bypass the lower roller on the left side, and the upper one on the right. Then two extreme links are combined and a pin is set. After the chain is installed, the axis is inserted into the squeeze, fixed with a screw and a pin is pressed in. If the latter has caught up with the edges of the chain, then everything is done correctly.
After installation, check the chain travel. It should not have sagging, pedal scrolling should be free. If the pedal travel is tight or the chain sags, then using the same squeeze, using the second seat, we adjust the second axis.
Practical tips
There are times when it is urgently necessary to remove the chain from the bicycle, but there was no squeezing at hand. In this case, you can apply the old method - riveting.
When you remove the chain again, you should use different links, since the pinch pin loosens them.
If you regularly remove and install a solid bike chain, you should put a lock on it. This will greatly facilitate the process.