try a lower gear, it may help with the knee pain (higher cadence). it also may have to do with saddle height being a little low or maybe the saddle is pushed forward a little too much. if the saddle is too low, you put a lot of stress on your patella and quadriceps. I had the same type of problem and read up a lot about the different types of causes and effects of knee pains from cycling. I moved my saddle back and a little higher and the knee problem went away. now, this worked for me. not saying it will solve your knee pain, but trial and error is what I went through to find my sweet spot on the bike. also, adjust a little at a time.....it could just be a cm height adjustment.