I've been biking since 2012. More seriously since last year. I bought new shoes (Sidi SPD-SL) last year. I did not have this with SPD and last year neither. In fact, I first had this pain last Tuesday. The following day I still had the pain during my commuting trip (5 km). Today, I did 75 km and it was quite hard to keep going at ~55 km so it does not happen right in. I checked the height of my saddle, my leg angle is about 150 degree and the cleat is properly aligned with the front of the knee (using a string with a lead). I tried different cleat position but I guess the injury was already done so it didn't help much. Is this the symptom of a specific thing? Big deal breaker... it's like in the front of the left knee, always the same leg.