So I don't know if this will get any responses, but I have basically given up on bike riding. I went to the podiatrist for new insoles for the flat feet. He noticed that I have very stiff ankes. He called it "ankle Equinus", which basically means that my foot cannot bend in a certain way. He says that might be a source of my knee pain that is caused from when I stand up while pedaling. Has anyone ever heard of this sort of thing before?