In order to independently repair and maintain a bicycle, it is advisable to have a good understanding of the device of its main running elements. One of the defining nodes in the system is a bicycle cassette. Let’s figure out what the specified mechanism is, and also find out how to dismantle and install it.
What is a bicycle rear cassette?
The mechanism is made in the form of a set of rear stars connected to the freewheel of the rear hub. Elements of the functional unit are fixed with a lock nut. The latter contains teeth that prevent unscrewing the mount during riding.
The rear cassette of the bicycle serves as a system designed to convert the transmission range of the transmission of a two-wheeled vehicle. The use of stars of various diameters with a separate number of teeth makes it easier to move in difficult conditions and contributes to the development of increased speed during riding along flat roads.
Materials of manufacture
The bike cassette can be made of the following materials:
- Aluminum - has a low weight and the lowest density among all metals. A bicycle cassette made from alloys of this material is a fairly expensive option. Mechanisms of a similar plan are in great demand among experienced motorists, for whom the reduction in the total weight of a two-wheeled vehicle is of decisive importance.
- Steel is the most common material used in the manufacture of bicycle components. The main advantage of the material is increased strength, resistance to mechanical stress. An obvious disadvantage of steel is its increased weight. In fact, the steel bicycle cassette looks like the best option for the average bicycle enthusiast, because it has an optimal price-strength ratio. To protect such systems from the harmful effects of corrosion, manufacturers resort to chromium plating, burnishing and nickel plating of structural elements.
- Titanium. Bicycle cassettes made of the presented material are lighter than steel, but heavier than aluminum. The specified production base is characterized by increased strength. Therefore, titanium cassettes most often become the choice of consumers who operate two-wheeled vehicles in conditions of significant loads. The material, like its alloys, is not subject to corrosion. If the owner of the bike is not aimed at the maximum possible reduction in weight of the bike, it is worth choosing the titanium cassette, which will last much longer compared to the above options. The only disadvantage of this solution is the high cost.
Number of stars
The bike 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 for 8-10 stars. Similar systems are installed on the most numerous modern bikes, starting from mountain bikes and ending with highway bikes. 11 stars can be seen on Campagnolo cassettes. Their installation becomes available only when using a sleeve of a similar brand.
You can determine the nature of the existing cartridge by looking at the special markings. 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 varieties of bicycle cassettes:
- Collapsible - the most common group of mechanisms, where all the stars, in addition to the two smallest, are connected together with screws or rivets. A similar method of fixing structural members facilitates assembly and maintenance. At the same time, the implementation of such a solution is accompanied by an increase in the weight of the system and the tendency of its components to clog.
- On a spider - cassettes of this plan are made in the form of stars assembled on an aluminum frame, which, in fact, is called a spider. The last two are the smallest asterisks. Spider cassettes are easy to clean and lightweight.
- 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 a worn element. In this case, the second part of the system remains in a functional state. The presented mechanisms are lighter than collapsible structures. In addition, they are easier to clean from small debris and dirt.
- Open Glide - are monolithic cartridges that are designed for installation on road bikes. Such cassettes are fixed on the splines of the ratchet drum with a lightweight aluminum nut and a special cover on the other hand.
- X-Dome is another monolithic system. It is fixed at the small sprocket with a lock nut, and at the very base of the mechanism, a large sprocket serves as a fastening. Most often, the structural elements of the nodes of this plan are made of lightweight aluminum.
Replacing the bike cassette
To replace the mechanism, it is necessary to understand the features of its dismantling. Removing a bicycle 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. The bike cassette puller is needed to loosen the retaining nut. In turn, the keys are used to fix the elements of the mechanism in a fixed position.
How to remove a cassette from a bicycle? The work is performed as follows:
- A whip is put on the largest star , with which the system is held in a static position. The bicycle cartridge puller rotates with a wrench . The small star and slotted nut have a grooved surface. Therefore, when unscrewing the fasteners, sharp crunchy sounds can be heard, which should not be scared during work.
- The nut is unscrewed, after which the cartridge is removed. At the same time, it is worth paying attention to the dismantling of small sprockets, which can be worn on the sleeve regardless of 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.
- Individual parts are laid out in an organized manner, which allows you to reassemble the mechanism without confusing anything.
- Having figured out how to remove the cassette from the bicycle, in conclusion it remains only to assess the degree of wear of the sprockets and the condition of the system as a whole.
Cassette Lubrication
After disassembling the bicycle cassette, its elements must be carefully treated with a lubricant. Today on sale there is a special lubricant for cassettes in tubes. However, for these purposes, you can use any other non-lithium substance that has dust-repellent properties.
Cassette installation
Replacing the cassette on a bicycle involves dismantling it from the wide splines of the sleeve and installing a new set of stars, guided by the grooves available on them. In fact, the installation of the structure is the inverse operation of its dismantling. Here you need to make sure that the stars fit snugly on the ratchet splines. Work must be carried out slowly, which will avoid damage to the flanges of the splines.
Using the keys for the bicycle cassette, it is necessary to put the stars and rings on the ratchet, and then screw the clamping nut according to the thread. Here you must follow the order of the stars on the slots. The distance rings contain special pins that must enter the corresponding openings in the stars. If this requirement is missed, the stars will be located too far in relation to each other, which will affect the accuracy of the speed switching system.
The end nut must be tightened as tight as possible, using the same key to remove the cassette on the bicycle. It is completely undesirable for the locking element to unwind gradually while riding. Therefore, securing the system with a lock nut, it is worth moving the wheel to a vertical position, thoroughly pushing the key lever.
Recommendations
As you can see, disassembling and reinstalling the bicycle cassette is not so difficult. Attention here requires a final check of the system. Before leaving, you must make sure that the stars are not unbalanced in relation to each other. It is also worth making sure that the same distance is maintained between the stars.
Finally
Replacing the cassette on a bicycle and its maintenance is work, which does not require special skills from the owner of the bike. The determining issue is only the availability of specialized tools. As for the choice of a new cartridge for replacement, it is worth sticking to the desired
gear ratio.