1. Measure from a point on the axle to a point on the rear fender.
2. With the rider geared up, sit on the bike in a normal riding position and take the same measurement.
100mm is ideal, up to 110mm is acceptable for a stable ride in
higher speed bumps. As little as 95mm can work well in
super tight woods riding.
Once rider sag is set, free or static sag (the same measure
only with bike weight, no rider) should be 20mm to 40mm.
Less than indicates a heavier spring rate is needed. More
than indicates a lighter spring is needed.
With the axle pinch bolts loose and the axle nut tightened, hold the
front brake and push down on the forks several times. Next torque
axle pinch bolts with the weight of the bike on the front wheel.
Lowering the rear end or raising the front reduces cornering ability but
enhances straight line stability. Conversely, raising the rear or lowering
the front makes cornering easier but diminishes stability.
Chassis tuning can be accomplished by adjusting shock spring preload
or by moving the fork height in the triple clamps.
Compression damping controls the force needed to compress the suspension.
More damping means stiffer, less means softer. Pretty basic. Bigger bumps and jumps require more damping. Smaller, acceleration and braking bumps; roots and rocks need softer damping settings. Try to set compression as soft as possible for the terrain. Avoid excessive bottoming but try using most all travel for conditions being ridden. Most shocks have high and low speed compression adjusters. Think of shaft speed. Big sand whoops, low speed. Roots, rocks and hack are high speed damping.
Rebound damping controls the force of compressed springs. More rebound
damping means slower return after compression, less damping
the faster the return. If you get a kicking sensation, slow the rebound.
Packing is a common problem. A series of bumps in succession, like acceleration
hack, too much rebound damping does not allow the shock
to return to absorb the next bump. The shock is into the stiffer part of
the stroke and cannot absorb the next bump.
Speeding rebound also slightly deceases compression damping.
Make adjustments in increments of 1-3. Go back to the original settings if you feel no progress is being made. Sometimes problems are opposite of what they seem. A suspension that feels too stiff can actually be too soft and settled too far into the stroke.