1. Fix the car first, remove the cover of the left crank of the bicycle center shaft with an Allen wrench, and then remove the left crank with a wrench.
2. After removing the crank, remove the chain by hand, hang it on the five-way connection, and push out the toothed plate with the palm of your hand.
3. After pushing out, put away the toothed plate and remove the intermediate shaft with the intermediate shaft wrench. The central axis is engraved with an arrow and rotates in the direction of the arrow. There is a washer on the intermediate shaft.
4. The shaft is covered with dust. Pick it up slowly with a knife and you can see the direction.
5. Dust the bearing and clean the bearing with detergent or diesel oil.
6. The cleaned central shaft can be lubricated after cooling.
7. After lubricating the oil, put the dustproof seal of the bearing in place, and then install the central shaft in turn according to the disassembly method.