What Are the Differences Between Single Speed Freewheels and Fixed Gears?

Single-speed freewheels and fixed gears are both popular drivetrain setups used in cycling, each offering unique characteristics and riding experiences. Understanding the differences between these two systems can help cyclists choose the one that best suits their preferences and riding style. 
Mechanism of Operation:
Single-Speed Freewheel: In a single-speed freewheel setup, the rear cog is attached to a freewheel mechanism. This mechanism allows the rider to coast without pedaling while the rear wheel continues to rotate freely. When the rider stops pedaling, the freewheel mechanism disengages, allowing the rear wheel to spin independently.
Fixed Gear: In contrast, a fixed gear (or ""fixie"") setup lacks a freewheel mechanism. Instead, the rear cog is directly connected to the rear hub, meaning that the pedals are always in motion whenever the bike is moving. This results in a direct and immediate connection between the rider's pedaling and the rotation of the rear wheel.
Coasting and Backpedaling:
Single-Speed Freewheel: With a single-speed freewheel setup, riders can coast by stopping pedaling while the bike is in motion. Additionally, they can backpedal freely without affecting the motion of the rear wheel. This allows for greater flexibility and ease of maneuvering, especially when navigating tight spaces or executing tricks.
Fixed Gear: Coasting is not possible on a fixed gear bike due to the direct connection between the pedals and the rear wheel. As a result, riders must continuously pedal whenever the bike is in motion. Additionally, attempting to backpedal on a fixed gear bike will cause the rear wheel to rotate in the opposite direction, requiring a different technique for slowing down or stopping.
Riding Experience and Control:
Single-Speed Freewheel: Single-speed freewheel setups offer a more traditional riding experience similar to that of a multi-speed bike but with the simplicity of a single gear. Riders have the ability to modulate their speed and coast when desired, providing a comfortable and familiar feel for most cyclists. This setup is versatile and well-suited for commuting, recreational riding, and casual cycling.
Fixed Gear: Riding a fixed gear bike requires a higher level of engagement and control due to the constant connection between the pedals and the rear wheel. Riders must maintain an awareness of their pedal stroke and anticipate changes in speed or terrain. This results in a more immersive and responsive riding experience, appealing to cyclists seeking a direct connection with the bike and the road.
Braking and Skidding:
Single-Speed Freewheel: Braking on a single-speed freewheel bike typically involves using traditional rim brakes or disc brakes, depending on the bike's setup. Additionally, riders can perform controlled skids by locking up the rear wheel while coasting, allowing for precise speed adjustments and stylish maneuvers.
Fixed Gear: Braking on a fixed gear bike primarily involves using the rider's leg muscles to slow down or stop the bike's motion by resisting the forward pedal motion. This technique, known as ""skidding"" or ""skipping,"" requires skill and practice to execute safely and effectively. Some fixed gear bikes may also be equipped with additional braking systems, such as front brakes or auxiliary devices like a rear brake.
Customization and Versatility:
Single-Speed Freewheel: Single-speed freewheel setups offer a high degree of customization and versatility, allowing riders to easily change gear ratios by swapping out cogs and freewheels. This flexibility enables cyclists to tailor their bike's gearing to suit different riding conditions or preferences, whether it be for speed, climbing, or cruising.
Fixed Gear: While fixed gear bikes can also be customized to some extent by changing the gear ratio, the options are more limited compared to single-speed freewheel setups. The fixed nature of the drivetrain means that gear changes require replacing either the rear cog or the front chainring, making adjustments less convenient.