I got a 2005 can am ds650x with a brand new carb on it. It runs good idling and revs up and in 1st and 2nd gear can handle full throttle for a few seconds then it spits and spudders. If I’m in third gear or above anything past half throttle it spits and spudders and starts to die if I don’t let off the throttle. For the few seconds in 1st or 2nd gear full throttle will make it stand right up plenty of power till it starts to die again. Any ideas what is going on???