I've been experiencing some post-bicycling knee achiness. At times, I don't appreciate the absence of pain or discomfort until something is amiss or shall I say that I don't fully appreciate the joy of fluidity until, to borrow a title from Chinua Achebe, things fall apart.
I saw an article about (arm, elbow, hand and knee etc.) pain in the July/August 2009 edition of Fitness Magazine.
I don't feel a grinding in my knee when I'm bicycling but the suggestion for bike-related knee pain helped out.
Now, I try to make sure that my foot is pointing forward which has, fortunately, cut down on the knee achiness. I would hate to give up bicycling especially since I so recently rediscovered it.