I have a 06' yfz 450 bored out to 480 with the Athena kit, And a trinity big exhaust. They make a quiet core for that pipe that goes in the end tip, but low end would suffer and bog unless you put around a 42 main jet, I believe there's a 48 in there, I'm not sure if any brands slide nicely onto that big Trinity head pipe without changing that too. The needle in that carb is from a yfz dirt bike on the 4th position. So I've never done it. My quad is LOUD, and it's going to bite me soon, so if anyone has suggestions and not just suggestions but if I will suffer from power loss, or end up hurting the engine or bike in any way that would be appreciated, thanks!