Originally Posted by terrymorse

That seems like patellofemoral pain syndrome. It can happen when you increase your riding load, before your muscles have adapted to the new stress. I seem to get it every year, in the early season (I have a little of it right now, in one knee).

Ibuprofen and ice after a ride, avoid mashing in the hills, ramp up efforts gradually. Here's a little guide: Patellofemoral pain syndrome