Shock preload

  (this is old rule of thumb)
  Ideal spring rate and sag
  1. As a general rule, you want about 9-10 mm preload with 100 - 106 mm sag. 
    • You don't want to turn the spring more than 1 1/2 turns either direction to get the correct sag.  If you have to turn the spring more than 1 1/2 turns either direction, this indicates you may benefit with a different spring rate.