2. Remove the sprocket and chain together, and replace the chain.
3. Find the official point of the large and small sprockets (there is a point on the L sprocket that is the official point), and there is also that official point on the chain, and the corresponding sprocket puts the chain on the sprocket.
4. When replacing the 7OC motorcycle, the chain tensioner will finally install the sprocket and tighten the bolt (80N).