Front freewheel
A front freewheel or freewheel crank is a freewheel mechanism used on some bicycles which enables the drivetrain of the bicycle to continue spinning while the rider rolls, but stops pedaling, or coasts. Unlike regular bicycles, a front freewheel can make it possible to shift gears using a derailleur while the rider is coasting if paired with a fixed rear hub or a freehub with a slight resistance in the freewheel mechanism, which causes the chain to continue spinning with the wheel rotation.