Lol one minute your giving up on it and selling; 50 minutes later your gonna try a tune up. Imo i would keep it bc it sounds like your hesitant. However i will say to anyone, there isnt really more smoothness or throttle response in a fi vs carb bike. Call me a liar but ive rode both and felt no difference. If everything is in sync a carb bike will run just as smooth. Where fi has the upper hand is maintence, easy starts, consistent fuel delivery(even during wheelies), and a few other things im forgetting. Good luck which ever path you take, a 06 gsxr will be an excellent bike btw... Jus saying