I rode with a buddy today, and his bike made a God awful noise with each rotation of the crank, always at the same spot too. I said "lube your pedals" and he said that they wee almost new, hmmm!

After the ride, we took the R pedal off, lube the threads and reinstalled it. Then, just for giggles, lubed the pedal shaft and his clips too (yes we did the shoes as well).

We went out for a quick 3 mile hard ride, and the bike did not make a sound...noise gone.

Lesson, take something off the bike that you think is the problem, clean/lube it real good then reinstall. I would guess your chain is dirty, lacks lube or needs replacing.