Perfect Grip Thanks to High-Speed and Low-Speed Compression
The compression stage is the opposite of the rebound stage, namely the load on pressure. This setting allows you to control the compression of your suspension component(s) on the MTB. The higher the compression damping, the slower the suspension component compresses, both when pressure is applied from above (for example, in the saddle) and when riding over bumps. Less compression damping means an active chassis, but it can also feel jumpy. More compression damping reduces the sensitivity of the spring component, but provides more counterpressure.
A special feature of a compression damper is a platform damper, which is in addition to or instead of a fine-grid adjustment. Usually a platform damper has a few, strongly differing stages, e.g. "Open - Pedal - Lock" by Rock Shox or the "Climb Switch" by Fox or Cane Creek. Unlike a real lockout, the closed mode here also does not completely block the oil flow in the damper.
As with rebound, particularly high-quality suspension components also differentiate between high- and low-speed compression and thus allow your MTB suspension system to be finely adapted. A stronger low-speed compression damping with less high-speed would, for example, ensure that the suspension does not sag on smaller impacts, but immediately releases the necessary suspension travel on larger impacts. Unlike rebound, compression damping has a relationship between the speed of suspension movement and the low- or high-speed setting. Low-speed compression dampens the compression against slow movements such as pedalling while standing or pedal input. High-speed compression is responsible for the fast strokes that mean high piston or shaft speeds.
Tip: Closing the compression damping almost completely on a mountain bike uphill is fairly common, but often inefficient and uncomfortable. As soon as you leave the smooth-as-a-baby's-bottom asphalt, an active chassis that ensures that the tyres follow bumps and do not lose contact with the ground is usually the most energy-saving and best solution – especially for uphill riding.