Wilbers model 640 is a rear shock with:
Rebound damping adjust.
Available with either Threaded or Hydraulic Preload Adjuster for optimum sag setup. (see *Recommendation, below)
Fully rebuildable and five year warranty.
Two Spring & Knob color choices:
Blue Springs with Red Knobs.
Black Springs with Grey Knobs.
See menu above to select.
*Recommendation: Please note that it is extremely difficult to access the Threaded Preload Adjuster on this model. Therefore it is HIGHLY recommended that this product be purchased with the Hydraulic Preload Adjuster option. The Threaded Preload Adjuster is designed for the rider whose loads do not change and therefore seldom needs to adjust the spring tension on the rear shock.
Recent email about this product:
"Have put some good miles on my 2009 BMW K1300S (we) installed the Wilbers shocks I purchased from you last October ( he had recently done the same on his '09 ). Even though he put new tires on at the same time, I could and still do feel a marked improvement in handling and riding comfort. Just as advertised. Not missing the factory ESA............"