I am assuming that you mean the heat from them? If you are careful to not have them against the metal of the exhaust there should be no problems, i used my soft bags with both stock exhaust as well as aftermarket and never had a problem with heat. I also came up with a cheap way to keep the saddle bags spread for day trips. PVC pipe on the up folded rear foot pegs spanning the distance to the fairing works well to give the bags support.