Suspension on your motorcycle serves two functions: compensating for the weight you have on the bike and compensating for road conditions. Suspension technology has taken some giant leaps in recent years but the basics are pretty much unchanged. There are two main adjustments.
The first adjustment is preload. This allows you to compensate for the weight of your equipment, yourself, and your passenger for example. This can usually be adjusted by turning the knob. On some models, the adjustment can be made electronically using the ESA or electronic suspension adjustment.
The next adjustment is for damping. This makes suspension either stiffer and more responsive, which is ideal for performance-oriented riding, or softer for a more comfortable shock absorbing ride. With bikes equipped with electronic suspension adjustment, you can make the adjustment by pushing a button even when riding.
Keep in mind that every combination of rider, motorcycle, skill set. and desired ride experience are different. So a good start is to check your Rider's Manual for suggestions on setting up your suspension for the ride you want to experience.
Link to watch BMW Motorrad USA Video: Suspension Basics
