Sag
First you put the bike on a stand and measure from center of axle to a fixed point on the rear of the subframe somewhere, record that measurement, then sit on the bike centered with full riding gear and have a friend measure from center of axle to same piont you preveously measured to, record that measurement. Now subtract that measurement from the FIRST measurement ant that is your sag. If your sag is 118 you need to adjust the shock spring adjusting nut down to put more force on the spring thereby reducing your sag, do this till you reach a setting of 100. The procedure is just the opposite if you have a setting of 80, you then would adjust the nut up reducing the force on the spring. GOOD LUCK:)