If your shocks have rebound adjustment(doens't look like they do) there is a small flat head screw at the bottom of the shock below the spring and above the mounting point. Rebound adjust how fast the shock returns to it's normal position after being compressed. There are 2 types of compression, high speed and low speed. (need more pics to see what you have) High speed adjustment is for when you take a big hit, land flat off a jump, hit a square edge, blast through a G out, ect.. The Low speed controls the compression from body roll and the subtle bumps and hits that your quad takes. Like landing a jump pefect on the downhill side in the sweet spot, that is low speed.
High and low speed compression have nothing to do with your speed, it is the speed at which the shock shaft travels.
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