Jimbo- Almost all HD dealers will honor your warranty in fact, most of them stock and install aftermarket pipes etc. It is profitable to them to sell these products (V&H, Custom Dynamics etc.) so they do their best to assist their customers. The real issue takes place with corporate if they feel the parts installed are implicated in the warranty dispute or they can prove harm to the bike due to those parts. If and when this occurs, the dealer is caught in the middle. The recent EPA ruling and fines have the Motor Company a bit edgy but the fact is, now you can make additional power in your stock engine by using off the shelf genuine HD parts.