There are a number of reasons why you might need to remove and replace a bike freewheel. You may need to service the bearings on the wheel hub, replace a spoke on the drive side of the wheel, or maybe to replace the cassette itself.
This is a long guide, so you can choose to either watch the entire video above, or follow it in smaller chunks by clicking on the individual steps below.
Steps to Replace A Bike Freewheel:
A freewheel is a ratchet mechanism mounted on the rear hub which allows the chain to drive the wheel forwards via a cog but when the wheels move faster than the chain the cog is not driven round by the wheel. A freewheel allows a rider to rest their legs while the bike is moving forward.