The chain is the key part of the bicycle transmission system. Riding tension will make the chain spacing become larger and larger, accelerate the wear of flywheel and tooth chainrings, make abnormal noise, even break the chain in serious cases, causing personal injury.
To avoid this, share with you today how to determine whether the chain needs to be replaced and how to quickly replace the bicycle with a new chain.
When to replace the chain?
All modern chains have a rivet every half-inch, and you can measure it with a standard ruler, from one rivet to another 12 inches away. Before starting to measure the chain. Align the zero mark of the scale with the center of the rivet and look at the position of the 12-inch mark line on the scale.
If it is the center of another rivet, it means the chain is functioning well. If the rivets are less than 1 / 16 inch of the marking line, the chain is worn but can still be used. If the rivets exceed 1 / 16 inch of the marking line, you need to replace your chain at this time.
How to replace the new chain?
1. Determine the chain length
According to the different tooth chainring, bicycle chain can be divided into three types (single speed vehicle is not within the scope) single chainring, double chainrings, and three chainrings, so the judgment method of chain length is different. First, we need to determine the length of the chain.
The chain does not pass through the back dial, passes through the largest tooth chainring and the largest flywheel, forms a complete circle, and then leaves 4 chains.
After the chain passes through the back pull, passes through the largest tooth chainring and the smallest flywheel to form a complete circle, the straight line formed by the tension wheel and the guide wheel crosses the ground, and the angle formed is less than or equal to 90 degrees. Such chain length is the best chain length.
The chain does not pass through the back dial, passes through the largest tooth chainring and the largest flywheel, forms a complete circle, and then leaves 2 chains.
2. Determine the positive and negative sides of the chain
Some chains can be divided into positive and negative sides, such as Shimano 570067007900 and mountain hg94 (New 10s chain). Generally speaking, the side with the font facing outward is the correct way to install.
The chamfering on the front and back of the bicycle chain is different. If the front and back are installed wrong, the chain will break in a short time.
3. Installation mode of chain
When we install the chain, should the direction of the inner and outer guide plates be on the left or the right? The correct installation direction will make your chain stronger, and it will not break easily when you trample on it.
The correct way is that the inner guide plate is on the left and the outer guide plate is on the right. When connecting the chain, the link is at the bottom, as shown in the figure below.