tuner

Hey all, been debating on an exhaust for my 1000R, Everywhere I've looked has stated that I need to have a fuel tuner to put an exhaust on? Does this sound right to everyone? What if I just put on a Slip-On? What is a fuel tuners purpose for an exhaust? Thanks...

I have a 2013 Maverick 1000R and I have a Check Engine Light with a few minor codes dealing with fuel delivery. I would like to reset or clear the ECU with the battery terminals unhooked for a while, basically draining all power from the unit but I am wondering if this is safe with the BPI Tuner...