Depending on how bad they discolored check with a local Harley shop for a cleaning product called blue away bikers use on their exhaust. It may have other names but may help. they will always discolor again. As said above Do not wrap them for street use. If you chose to get them coated go with a known good company. I had a local do mine because I was too cheap to go with JET HOT. Cost me $250 bucks and now I have to do it again because it didn't hold up.