I am glad you are able to get on a bike and ride. I am putting off any kind of surgery for now. I am able to ride my vintage racing bikes(not fast!) without any discomfort right now but when I go for my morning walks I feel it. I have a "third knee cap" due too a full bursa sack that has been drained numerous times and looks ugly but it causes me no problems. I went to an Orthopedic surgeon and he had me get an MRI . He told me I would know when it is time. I am 67 and have been very active all my life and it is inevitable for most of us to have knee problems. Good luck and just keep pedaling......