not to keep on this but i've seen many many bike run drag pipes and run for years and years with no problems so i don't see your point . i know engines need a curtine amount of back pressure to "run correctly" of so the factory will tell you . car dealers will tell you that a cold air intake and free flowing exhaust won't do you ant good either but i know that is false . its cool though . your probably just old and don't like loud music either ! that was a joke by the way .