enzoracing Enzo Racing High Speed Compression Adjuster for KYB Shock Uses and Directions: What is the "high speed compression adjuster" on my shock? The high speed compression adjuster on both KYB and SHOWA rear shocks is the outer nut on the compression adjuster mechanism. The screwdriver slot is the low speed compression adjuster which controls a needle and seat flow restrictions. The high speed adjustment controls the amount of preload on a coil spring which puts pressure against a leaf valve stack. What performance changes does the high speed compression adjuster make? Basically, high speed compression adjustments change the performance when the rear shock is compressing at high speeds in long stroke situations such as landing from big jumps. Additionally, riding into deep holes or hitting steep jump faces also compress the rear shock in long stroke situations and are affected by the same adjustments even though the actual shaft speeds are not as high. When the adjustments is adjusted stiffer (turned in clockwise) the rear shock action becomes firmer; resisting bottoming or just making the rear shock have more compression damping in situations that make the shock compress too easily. Occasionally, increasing the high speed compression adjustment may actually make the rear of the bike feel taller, but it is actually just the function of the damping force. If the adjustment is made softer, counterclockwise, the rear shock action will become easier to compress. Why have a specific tool for adjusting high speed compression damping? As discussed previously, the high speed compression adjustment changes the amount of spring preload on a leaf valve stack. This preload is very sensitive to the overall firmness of the adjustment setting yet has no detent positions. It is only a threaded plug that changed the position against the coil spring. Settings are specified as 1 1/2 turns out which means that after the adjustment is turned all the way clockwise(maximum), it is then turned out (counterclockwise) one complete turn plus another 1/2 turn. This can be done with a T-handle or even a wrench, but it is not as accurate as using the ENZO TECHNICA HIGH SPEED COMPRESSION ADJUSTER. Situations when adjustment may be needed: Here are some examples of when high speed compression can be adjusted. If the rider feels that the shock compresses easier than the front fork in sections where both ends are compressing using a lot of travel such as riding in a deep hole or hitting a tall, steep jump face, you should increase the high speed compression setting. If the rear feels like it is overpowering the front fork action in similar situations, and making the front dive down more you reduce the high speed compression setting. It is basically an adjustment where the full stroke action can balance front to rear. Damping is speed sensitive action, not position or load sensitive, which is referring to the shock spring.