Rear bike cassette: description, features of repair and replacement

In order to independently repair and maintain the bicycle, it is advisable to have a good understanding of the structure of its basic running elements. One of the defining nodes in the system is a cassette of a bicycle. Let's figure out what the mechanism is, and we'll figure out how to dismantle and install it.

What is the rear cassette of a bicycle?

The mechanism is made in the form of a set of rear stars connected to the free wheel of the rear hub. Elements of the functional unit are fixed with a lock nut. The latter contains teeth that prevent unscrewing of the mount during the ride.

The rear bicycle cassette serves as a system for converting the transmission range of a two-wheeled vehicle transmission. The use of stars of different diameters with a separate number of teeth makes it easier to move in difficult conditions and promotes the development of increased speed during driving on flat tracks.

Materials of manufacture

The bicycle cassette can be made of the following materials:

1. Aluminum - is low in weight and has the lowest density among all metals. A bicycle cassette made of alloys of this material is a rather expensive option. The mechanisms of such a plan are in great demand among experienced amateurs, for whom the reduction in the total weight of a two-wheeled vehicle is of decisive importance.
2. Steel - the most common material that is used in the production of bicycle components. The main advantage of the material is increased strength, resistance to mechanical stress. The obvious drawback of steel is increased weight. In fact, a steel bicycle cassette looks like the best option for an average bike enthusiast, because it has an optimal price-to-strength ratio. To protect such systems from the corrosive effects of corrosion, manufacturers resort to chrome plating, blasting and nickel plating.
3. Titanium. Bicycle cassettes made of the presented material are lighter than steel, but heavier than aluminum. This production base is characterized by increased strength. Therefore, cassettes made of titanium often become the choice of consumers who operate two-wheeled vehicles under conditions of significant loads. The material, like its alloys, is not corroded. If the owner of the bike is not aimed at the maximum possible weight reduction of the bike, it is worthwhile to choose the titanium cassette, which will last much longer than the above options. The only disadvantage of this decision is the high cost.

Number of stars

A bicycle cassette can be selected based on the number of stars. The mechanisms that contain 7 stars can be found on old bicycles. The most common cassettes are 8-10 stars. Such systems are installed on the most numerous modern tales, from mountain to highway. 11 stars can be seen on the tapes produced by Campagnolo. Their installation becomes available only when using a bushing of a similar brand.

You can determine the nature of the existing cassette by looking at the special labeling. So, the designation "11-36T, 10 speed" indicates that the largest star contains 36 teeth, and the smallest - 11. In total there are 10 stars.

Types

There are several types of bicycle cassettes:

1. Collapsible - the most common group of mechanisms, where all the stars, in addition to the two smallest, are combined into a single whole with the help of screws or rivets. This way of fixing the elements of the structure facilitates the assembly and maintenance. At the same time, the implementation of this solution is accompanied by an increase in the weight of the system and the propensity of its components to clog.
2. On the spider - cassettes of this plan are executed in the form of stars, assembled on an aluminum frame, which, in fact, is called a spider. The latter is joined by two stars of the smallest size. Cassettes on the spider are distinguished by the ease of cleaning from dirt and light weight.
3. On several spiders - expensive products that are installed on professional models of bicycles. They consist of two spiders, each of which is joined by sets of 2-3 stars. The main advantage of this solution is the ability to quickly replace the worn out element. The second part of the system remains in the functional state. The presented mechanisms are easier to dismantle structures. In addition, they are easier to clean from small debris and dirt.
4. Open Glide - are monolithic cassettes that are designed for installation on highway bicycles. Such cassettes are fixed on the grooves of the ratchet drum with a lightweight aluminum nut and a special lid on the other side.
5. X-Dome is another monolithic system. It is fixed at the small sprocket with a counternut, and at the very base of the mechanism the big sprocket serves as the fastening. Most often, the structural elements of the nodes of this plan are made of lightweight aluminum.

Replacing the Bicycle Cassette

To replace the mechanism, you need to understand the features of its dismantling. Removing the cassette is a fairly simple task. However, its implementation requires the use of a specialized tool in the form of a puller and a whole set of keys. A bike cassette extractor is needed to loosen the retaining nut. In turn, the keys are used to fix the elements of the mechanism in a stationary position.

How do I remove a cassette from a bicycle? The work is performed as follows:

1. The whip is put on the biggest star , by means of which the system is held in a static position. The wrench of the bicycle cassette rotates with a wrench . A small star and a slotted nut have a rippled surface. Therefore, when unscrewing the fasteners, sharp crunchy sounds can be heard, which should not be frightened during work.
2. The nut is unscrewed, after which the cassette is removed. In doing so, it is worth paying attention to the dismantling of small asterisks, which can be put on the bushing independently of the other elements of the system. Between them are pads in the form of washers, which must be carefully removed, so that they do not crumble.
3. Individual parts are laid out in an organized manner, which allows you to reverse the assembly of the mechanism, not confusing anything.
4. Having understood how to remove a cassette from a bicycle, in the end it remains only to estimate the degree of wear of the asterisks and the state of the system as a whole.

Lubricating the cassette

After disassembling the bicycle cassette, its elements must be carefully treated with a lubricating compound. Today on sale there is a special lubricant for a cassette in tubes. However, for this purpose, any other non-lithium substance that possesses dust-repelling properties can be used.

Installing the cassette

Replacement of the cassette on a bicycle involves its dismantling from the wide slots of the bushing and installation of a new set of stars, guided by the grooves on them. In fact, the installation of the design is the reverse operation of its dismantling. Here it is necessary to make sure that the asterisks fit snugly on the grooves of the ratchet. The work must be done slowly, which will avoid damaging the flanges of the splines.

Using the keys for the bicycle cassette, you must put the stars and rings on the ratchet, and then screw the clamping nut according to the thread. Here it is necessary to follow the order of the set of stars on the splines. Remote ringlets contain special pins that must enter the appropriate openings in the stars. If we miss this requirement, the stars will be placed too far in relation to each other, which will affect the accuracy of the switching system.

The end nut must be tightened as tightly as possible, using the same key to remove the cassette on the bicycle. It is completely undesirable that the locking element gradually unwind during driving. Therefore, fixing the system with a lock nut, it is necessary to move the wheel to the vertical position, pressing firmly on the key lever.

Recommendations

As can be seen, dismantling and re-installation of the bicycle cassette is not a difficult task. Attention here requires a final test of the system. Before leaving, you must make sure that the stars are not unbalanced in relation to each other. It is also worthwhile to make sure that the same distance is maintained between the stars.

Finally

Replacement of a cassette on a bicycle and its maintenance is a job that does not require special skills from the owner of a bike. The only question is the availability of specialized tools. As for the choice of a new replacement cassette, here it is necessary to adhere to the necessary gear ratio.