Just recently took a trip to Hatfield/McCoy trails over the weekend, I bought a quiet core/spark arrestor for my rs-2 pipe so I was compliant with any decibel testing they do. On the trails with the quiet core/spark arrester it would bog on the top end of the gears and sort of cut out for split seconds. The following day I decided to take the quiet core/spark arrestor out and risk getting busted. The bike ran great without any bogs on acceleration, but on deceleration the bike would pop and backfire at higher RPM's during deceleration. The bike has a jetting problem no doubt but don't know where to start. Bike stock is with a full yoshi rs-2 only other mod is a K&N filter with stock airbox (lid on). I live in PA and in order to ride alot of the trails you need to pass decibel tests, I'd like to be able to keep the quietcore/spark arrestor in to be compliant. WHERE TO START... Too lean with QC/SA or too rich with QC/SA. Everything Ive red suggests too lean if popping on decel. But would the QC/SA chock it up so much to make it too rich??