04 Raptor 660. All stock from what I know (not original owner). My son took out all the wadding and spark arrestor from the stock exhaust (to make it louder) and I did the parking brake and rev limiter delete. Cut the green/yellow wire at CDI and cut the green/white wire at CDI and ran a wire to the negative on battery (from green/white wire). Throttle stumbled starting at about 1/4 to 1/2 throttle and had loss of power. Took off carbs and clean them, adjusted clips from third from bottom to second from bottom on both. Seemed like it helped a little with the stumbling but still loss of power. I have done extensive research and most everyone says its the jetting since it runs (not the CDI) and not the parking brake and rev limiter deletes if done right. Would gutting the stock exhaust be enough to have to rejet the carbs?