I want to upgrade my Older style FMF exhaust with one of the White Bros E2 slip-on exhaust and I was wondering if I need to re-jet the bike. A couple of my friends said that since I was just replacing my muffler that I did not need to re-jet. I have not purchased the new exhaust yet but i want to make sure I have everything i need before I start to mess with my bike... Thanks for your input!!! Patrick M.