1. Check the chain:
The chain will be stretched after long-term use. The pitch of the chain is 0.5 inch. The length of 24 chains measured should be 12 inches. If the length has exceeded 1/8 inch of the normal length, the chain should be replaced.
2. Clean the chain:
If there is a lot of oil sludge in your chain, it may be time to clean it. You can use a chain washer to clean the chain, or remove the chain, find a container, fill it with solvent oil, put it in the chain, shake it to clean it, and finally take it out to dry and oil it.
3. Check flywheel and large gear plate:
If the flywheel will jump after the chain is renewed, the flywheel shall be renewed. If the tooth wear of the big gear plate is very large, and the chain is jammed, it shall also be replaced. Check the fixing screws of the big gear plate. If they are loose, they must be locked again.
4. Check the rim:
Check whether there are slight cracks near the air nozzle hole and steel wire hole. If there are cracks, replace the wheel rim as soon as possible, lift the wheel, rotate the wheel, and observe whether the wheel rim rubs the brake pad. If so, readjust the wheel rim.
5. Check the steel wire:
Check whether the steel wire of the front and rear wheels is broken. If yes, replace it. After replacing the steel wire, readjust the rim. When adjusting the rim, observe the direction of the rim deflection. If it deviates to the right, loosen the right steel wire near the rim, lock the left side, and if it deviates to the left, reverse it. The rim deflection should be less than 2mm.
6. Check the handle:
Check whether the driver is deformed in the accident, and whether there are cracks in the locking part of the riser. If yes, replace the handlebar.
7. Check the seat cushion and seat cushion rod:
Remove the seat cushion rod and check whether there is any deformation or crack. If not, replace it with a thin layer of grease. Check whether the seat cushion is damaged and whether the lower bracket is intact. If there is any problem, replace it.
