I am having the same problem. Had the bike at the LBS, they actually went through the exercise to swap out cranks and BB, no diff. Mine seems very pedal synched, also there when I stand. Noise worst when left pedal passes through 6 o'clock. When I lift load off the left pedal, no noise. I have greased everything around the pedal area, pedal threads, tried different pedals, greased the square spline, bolt threads and heads, nothing.