The chain is an essential component of the bike's drivetrain, responsible for transferring power from the cyclist's pedaling motion to the rear wheel, thus propelling the bike forward. It connects the front chainrings (attached to the pedals) with the rear cassette or freewheel, allowing for the transfer of power and gear changes.
The bicycle chain is a crucial component that requires regular maintenance and occasional replacement to maintain smooth and efficient operation of the bike's drivetrain.