I brought my bike to a bike mechanic Thursday afternoon. He showed me there was dirt on the small wheels that are the derailleur. He told me that the dirt does not belong there and also that the dirt got there due to the lubricant that I was using. He suggested cleaning the whole thing and also going to a teflon type lubricant. I have been riding in the rain lately and thought I should use the lubricant every time after riding in the rain. The lubricant I have been using is called Tri-Flow and applying to the chain after every ride in the rain. My question is how much damage is the dirt on the derailleur doing to my bike? If the lubricant is causing the dirt build up is there a better product out there for lubricant without the dirt build up? Thank you for your ideas and help.