so I picked up a 1991 seadoo gt for 500 bucks with a trailer and papers, ended up rebuilding the motor due to some bad crank bearings (the ball bearing cages in the pto side crank bearings broke apart, the engine still ran great but the actual ball bearings were touching each other in between the races causing a tapping noise) got it back together and its all back together now, the problem im having now is that for like the first 20 minutes of riding the engine is running really rough at higher rpms, it stutters and drops rpms and just sounds bad, but after riding it like that for a little bit it clears up and runs perfect. this only happens when I go to first ride it for the day and it clears up in about 20 min every time (I am letting it warm up before I get on the throttle). any ideas on what this could be would be greatly appreciated. p.s.a it didn't do this before the rebuild.