The Internals of a Suntour Coaster Brake/Freecoaster hub

Exploded hub without shell. (Brakepads not present. Large silver washer is acting as unbrake)

Hub compressed without shell. When the shell is present, and the cog is turned forward, the driver will screw into the clutch cone, which is then moved to the left, thus tightening itself onto the hub and permitting the shell to move with the cog. Notice how the unbrake shortens the distance the clutch cone has to move, thus eliminating the slack. (Notice the top and bottom picture have difference clutch cone locations. In the top picture it simulates when the rider is backpedalling or coasting. In the second diagram you can see how the clutch cone has moved outward. This is where the clutch cone would now be attached to the hub shell and cause the shell to turn as well)

This is the hub compressed, however missing the unbrake. Notice how the clutch cone now has nearly twice the distance to move in order to engage itself. This is what creates slack when the unbrake is not present.

Original hub instructions and diagrams provided by Patrick Schoolen. Photographs and text provided by Michael A. Kaminsky. (C) 2000