NEED HELP WITH THIS PROBLEM, ENGINE HAS 150 PSI ON BOTH CYLINDERS, REBUILT BOTH CARBS WITH FACTORY KITS, POP OFF WAS AT 38 AND 35 I LEFT IT AT THAT, FACTORY SETTINGS ON HIGH AND LOW SCREWS, 0 ON HIGH AND 1 1/2 ON LOW, SKI WILL CRANK AND IDLE FINE AT AROUND 1300 RPM LET IT WARM UP BY IDLING AROUND FOR ABOUT 5 TO TEN MINS. NEVER CUT OFF OR LOAD UP, IT WILL TAKE OFF FINE AND I CAN HIT THE THROTTLE WIDE OPEN WITH NO HESITATION BUT IT GOES ABOUT 50 YARDS TOP SPEED RUNNING FINE THEN IT STOPS AND WONT GO OVER ABOUT 3000 RPM, I CAN CUT THE ENGINE OFF AND WAIT ABOUT THREE MINS. AND CRANK IT BACK UP WHICH IT DOES WITH NO PROBLEM AND HIT THE THROTTLE AGAIN WIDE OPEN AND IT WILL GO TOP SPEED FOR ABOUT 50 YARDS AND STALL AGAIN AND WILL ONLY RUN ABOUT 3000 RPM, I CAN KEEP DOING THE STOPPING AND STARTING OVER AND OVER AND IT DOES THE SAME THING EVERY TIME. ANYBODY GOT ANY HELP WITH THIS PROBLEM?