Adjustable rate shock absorbers provide a means of changing the rate of dampening of the spring oscillations, to suit varying road conditions, or driver preference. This shock absorber has a manual, external damper rate adjustment.
The position of the valves in the piston can then be changed, to vary the number of restrictions the oil has to pass through, and to vary the force needed to open the valves.
In this position, all of the orifices are open, and a small dampening effect is applied to the oil. The spring force applied to the valve is also reduced to allow the valve to open more easily. This means the oil can flow through the valves more easily, which gives a softer ride, but can also allow more rolling and pitching of the body of the vehicle.
Closing some of the orifices, and increasing the spring force applied to the valves, makes it harder for fluid to flow through the piston. This increases the dampening effect of the shock absorber.
The method of changing the position of the valve varies. On this model, it is adjusted by a spindle that reaches down inside the plunger.
On this shock absorber, when it is extended to its maximum length, a pin is depressed, locking in an adjusting slide on the piston assembly. Twisting the two halves of the shock absorber changes the number of orifices, and the spring force on the valves.
