In Part One, we discussed sag, which puts your suspension in the right position, setting the stage for good performance. In Part Two, we talked about low speed compression and the various “platform” settings available on modern forks and shocks, recommending you try them wide open to fully utilize all that R&D that went into them in the first place.
For Part Three, we’ve once again turned to Duncan Riffle (Rockshox PR manager & 2x U.S. DH Champ), Mark Fitzsimmons (Fox’s pro athlete suspension tuner), Eric Porter (veteran pro mountain biker, Manitou test athlete) and Josh Coaplen (Cane Creek’s VP of engineering).
As a quick primer, your compression and rebound circuits control the motion of the suspension by controlling the rate of movement. Without it, you’d basically be riding a pogo stick. They do this by forcing oil through an orifice, and the size of that hole controls the speed at which the oil flows through it. Smaller holes mean slower oil flow, which means more damping. Bigger holes mean less damping, which equals faster movement. There are two types of control over hole size. Usually for low speed, you have a fixed port size with a needle or some other barrel that opens or closes access to that port in steps. High speed compression is typically handled with a spring or shim stack holding a seal over larger ports. With enough force, the shims flex or the spring is compressed and the ports are opened, letting more oil flow through to handle big hits. The strength of the shims/spring dictates the amount of force required to flex them. Your particular fork or shock may operate differently, but the principle is the same: Control oil flow and you control the rate of compression or rebound.
Here’s how to use that to your advantage and help keep the rubber on the trail…