Yep! My pipes colored just 10 miles into stage 1 tune with AC change and pipes opened up "straight thru" other than this blockage. During stage 1 upgrade I immediately removed my heat shields to watch for heat indicators (none at this time and 3k on bike with no mods). Then I removed the blockage as shown welded back together and sanded away the color (chrome heatshields cover it all anyway). Then after 300 miles and no coloring, I reinstalled my covers. And HD and others say NO restrictions.