I have a rocket system on my crf450r (flat tracker) and a Jemco down pipe. The rocket is do quite, next to most of the bikes, I cant hear mine! When I have the jemco on its around 109db. What mx slipon or system will get my bike to that level or close? Have you ever been passed by a LOUD bike? It disorients you if its loud enough!! Some people say White bros is the LOUDEST but they were absorbed by Vance&Hines