I would use Bar Keepers Friend about every 10,000 miles to return the cats and mufflers to the original sparkling stainless finish. No elbow grease needed like with metal polishes. Better living through chemistry. Even though I put a ton of miles on my ST I never wanted it to look like it had a ton of miles on it. I met a guy in a parking lot one time with an ST and we were admiring each other‘s bikes. He asked me how many miles you got on yours? I said 55 he replied 5500? No I replied 55,000 and that blew his mind that a motorcycle could roll that many miles. 55,000 is nothing remarkable in this forum.