I have a 2011 flhtcuse6 cvo with Vance Heinz monster oval pipes and a Harley tuner, my gas mileage was 40 to 44 until I hit 12000 miles. I thought I had bad gas the drop was so drastic but it didn't change no matter what I tried, plugs, air cleaner, different gas. Now I have 24000 miles and the MPG has dropped to 30 to 32 but the bike runs even stronger than ever. One other odd thing is the chrome tip on the left side has always had more soot and the chrome has pealed on three different tips over 20000 miles. Has anyone had this happen or have any thoughts?