Recently became a Wing owner after many years of waiting. The bike I bought is an '89 GL1500. The pipes on it are not stock and I want something much more quiet. I have spoken with one source about a new set and we have agreed on the price and so on. Now that I am doing a bit more research I'm finding that in some cases after a new exhaust installation, the carbs need to be re-jetted. I asked the source about that and his response was that if I was just installing them I wouldn't need to re-jet. I have no reason to doubt him but I am curious when and why re-jetting is required.