This EXR shock is a typical Motorsports 3-Way adjustable damper with a piggyback remote reservoir. The damping adjustments are high and low speed compression and rebound which mostly affects low speed rebound. Low speed damping is forces created by the shock in the shaft velocity range of 0-2.5 or so inches per second. Low speed damping mostly affects body motion like roll, dive and squat. High speed damping is at shaft velocities above this and mostly affects bump response and some transients.
So let’s dive in. Here is the EXR compression valving of the KW Motorsports damper pictured above. The parts are laid out as they are assembled into the shock body. The EXR valves are compact and fairly simple. The simplicity belies the fact that these parts are finely machined to very close tolerances and are very expensive to produce. This precision is needed because to have good control of low speed damping, a lot of control force has to be generated and adjusted very precisely with a super low volume of fluid flow.
Here is the valves laid out with the high and low speed circuits separated. The high speed circuit is on top and the low speed circuit is on the bottom.
Lets start with the manifold. It screws into the shock body and the remote reservoir screws into the other side of it. Its job is to transfer fluid between the shock body and the reservoir and hold the compression valves. The fluid flow to the remote reservoir is generated by the displacement created by the shock shaft as it get pushed into the shock body.