During the use of the bicycle, all the driving units of the drive wear out - the system (block of front sprockets), the chain and the cassette. Each unit is worn out individually. And so that your bike does not break in the middle of the path, you need to be able to determine the degree of wear of a particular part.
Instructions
Step 1
You can determine the wear of the sprockets by looking at the shape of the teeth. During the ride, the chain affects only the back side of the teeth, which means that this side is subject to wear. Each tooth on the new sprocket has a steeper back than the front. When worn, the front side does not change, while the back side is slightly "flattened", becoming flatter. As a rule, the resource of a cassette is about 10,000-15,000 km. This indicator can be either more or less, depending on the riding style and class of equipment. With severe wear of the teeth, the chain begins to slip during the active movement of the pedals.
Step 2
The wear of the system occurs in much the same way, with a change in the shape of the teeth. On the front sprockets, the chain begins to slip with severe wear. The service life of the system is about 20,000-25,000 km, but a heavily worn chain can significantly reduce its life.
Step 3
The chain wears out faster than the cassette, with a difference of up to 4000 km. The chain is worn out by pulling it out. To verify this, place the new and old chains side by side. You will see that with the same number of links, the old chain will be slightly longer when taut.
Step 4
The elongation of the chain is due to the wear of the link axes, and not due to the physical elongation of its plates. In other words, the chain is loosening. Thus, the distance between the links changes, and there is a difference between the teeth of the sprocket and the length of the chain link.
Step 5
Measure the distance between the centers of the first and 25th axles with a tape measure or linear. The new chain length is 304.8mm; in a fit condition - 304, 8-306, 4 mm. With a length of 306, 4-307, 9 mm, the chain is worn out. If the indicator is even higher, then the chain is very worn out. It is better to replace worn parts at the same time to avoid problems due to the different pitch of the cassette and chain.
