The original flywheel plate used for shimano Automatic transmission hub, 14 teeth is specially used for internal three-speed, others are generally used forshimanointernal three speed to internal eight speed.
Note: Shimano flywheels are not marked with Shimano mark. The difference between true and false flywheels is that the teeth of fake flywheels are rough. The teeth of genuine flywheels are polished smooth and feel good. It is common for thick toothed flywheels to support single speed chains, while the thin ones support single speed and external variable speed chains. For example, Panasonic mopeds need to use thin teeth to speed up and change the 16 tooth flywheel, and mountain bikes need to use thin plates to change the internal transmission.
You don't need to change the chain, or you can't determine whether your chain is wide or narrow.