- Determine the type of sleeve
- Cassette removal tools
- Disassembling the cassette
- Installing a new cassette
- Care of the tape and chain
After overcoming the mark of 1.5 thousand kilometers, it's time to carefully examine the tape. The wear rate will depend very much on the state of the chain and the type of surface you usually drive (say, in the mountains or on the roads). If the teeth of the gear wheels you use most resemble shark fins rather than rounded ridges (as on under-used wheels), you need to replace the cassette.
In some cases, it is possible to replace individual gears, but not all spare parts exist for all the cassettes, and, in general, it is safer to replace the entire assembly at once. If you doubt the feasibility of this or that option, consult a specialist.
Determine the type of sleeve
All the following steps to remove the cassette suggest that you have a drum bushing (with free play). Today, this type is installed on the majority of bicycle models, but it is still necessary to check. To do this, remove the rear wheel and carefully look at the smallest gear cassette. If the retaining ring (usually marked “Lock” on it) is located outside of it, then you have the drum bush installed.
Cassette removal tools
The retaining ring is designed to fix the gears on the hub, and when removing and replacing the cassette it must be unscrewed. To do this, you need three tools: a chain gate, a device for removing the retaining ring and a large adjustable wrench.
Disassembling the cassette
After removing the rear wheel, remove the eccentric mount from it. Then insert the device for removing the retaining ring into the cassette and twist until it is in the correct position (only one is provided). If your tape does not fit the standard device for removing the ring, contact your dealer or mechanic, and they will find you the right model.
To press tight to the gears, remove the springs from the eccentric mount and reinsert it through the wheels and the tool.
If your bike has a through axle that is screwed into the frame and not a standard quick-release mechanism, you can insert it through the ring-removing device so that all the components of the cassette will remain in place during disassembly.
Place the wheel flat on the ground, stand behind it, take the gate in your left hand and hook it on one of the large gear wheels of the cassette. In the right hand, take the adjustable wrench and fix the fixture for removing the retaining ring with it. In this case, the gate will not allow the cassette to turn during the dismantling of the ring.
Push the wrench and gate in opposite directions. As soon as you can loosen the ring, put the key with the collar and continue to unscrew manually.
After removing the retaining ring, remove the cassette. If you plan to reuse some of its components, dismantle the procedure very carefully.
Installing a new cassette
Put the new cassette on the bushing, making sure that the cassette you are purchasing is compatible with your bushing. For convenience, there are channels on the cassette case, and on the sleeve there are corresponding grooves, so that in principle you cannot install the cassette incorrectly. The largest gear should be closest to the spokes, with all the wheels facing the bevelled surface out.
Make sure that the cassettes are built in between all the wheels of the cassette, or that you are selling them with the cassette. After assembling the cassette, make sure that the distance between all the wheels is the same, and the smallest wheel protrudes slightly behind the sleeve body. Otherwise, you are more likely to miss one of the goals.
Replace the retaining ring with the same tool, then tighten (but do not overdo it) clockwise with an adjustable wrench. With the appropriate adapter and key with adjustable torque, tighten to the value recommended by the manufacturer. If you do not have such a key, entrust this part of the work to the specialists from the bicycle shop.
Replace the eccentric mount with the springs, put the wheel on and just in case check the operation of the mechanism when switching to all available types of gears.
Care of the tape and chain
Clean the cassette thoroughly at least twice a year. Avoid contact with water and do not use solvent as it may wash out the bearing lubricant.
When replacing the cassette, it is also advisable to replace the circuit. It wears out faster, and you will probably have time to change the circuit a couple of times before replacing the cassette for the first time. But it should be remembered that the chain and cassette must be compatible with each other. For example, for a 9-speed cassette, only a 9-speed circuit is suitable.
Read more about the care and maintenance of the bicycle chain. .
Note that the use of a worn chain leads to premature wear of the teeth of the cassette. This is especially true for regions with high humidity or sandy areas, since the ingress of water, dirt and sand into the transmission significantly reduces the service life of its components.
How to choose a tape read in the article Bike cassette: selection and maintenance