loss

Just got the carbs back on yesterday, synced them today, and tried to adjust the air/fuel mixture screw. The bike starts fine, idles fine, but I loose all power above 3500-4000rpm. like its hesitating, not enough fuel ? I have the air/fuel screws out at 5turns, which seems alot, but anything...

http://www.vidmax.com/index.php/videos/view/1508

Anyone know just how much power is lost w/ the cobra exhaust? I bought my bike with them already on so I don't have a 'before' frame of reference. However, on my first trip to the track she did run very consistent in both ET and trap speed - but the trap speed was always a click below 112 mph...