I had adjusted my disc brakes (Tektro Spyre-C) in such way that the gap between discs and pads were tiny (just enough to slide a sheet of paper).
Recently when I rode through a forest, there was a heavy rain and the front disc started ringing and creaking. The latter could be the effect of sand, the first one -- a cone? I took a look but because of the rain I could not see a thing. I figured out I pull the lever gently and wipe out anything that is stuck around the disc.
It worked. Too well. After a while I realized I had to pull the brake lever up to the handlebar to stop. When I get to home I noticed the gaps between disc and pads are much bigger.
I removed the pads now, they look ok (the contact/braking surface is around 2mm thick on both), the spring which separates them also looks healthy, I don't see I lost something, so now I wonder what happened? If I a not mistaken to make the gap bigger the only way is to adjust the screws which set the initial position of the pads.
Unless the pads were skewed in some way when I bought the bike and this rough ride "fixed" them. But then how it is possible for pads to be skewed in the first place and if it is a case why all (around 1500 km) braking so far didn't show or fix this?
Can anyone tell what could be the problem? Or what problem I have now I am not aware of? I am asking about it as well, because all I see is to do is to put pads back and adjust the screws to have a gap tiny again.