Yes, riding in the rain does cause an awful lot of wear and tear. When DS was racing and training, there were innumerable problems due to his training in all weather. I do keep an eye out for deterioration in all parts, though. The few mechanical things/parts that have broken, have been sudden things, like when my shifter cable broke going up a huge hill (thankfully, I was already in my granny, but not the low cog I needed). I have been on wet rides a bit more on my Jamis Coda, though, since I am more apt to go out to do errands with an iffy forecast; I need to take better care of that bike, though it is properly lubed, etc.