i have had some issues before like that , but first off get ride of those pos v force tazzanari blaa blla blaaa i have always had bad luck with v force 2s and 3s the 2s flow a little better but reeds seprate easy and come lose and get sucked into the motor . and the reason you dont have to jet v 3s is becasue they dont flow for shit , i had better luck with boysen (somewhat) and then got g3 power reed 6 pedal and they are a world of diffrance it leaned my cub out where i had to go up on the pilot , there is going to be a new reeds system from them on the market in 2 weeks that flows 74cfms right out of the box v3s flow like 50 . they are pricey but well worth it , i am running there old reed and it does great i have the new reeds on back order , when they come in ill take a pic of the big diffrance.
you may have already broke a ring or done something to the top end , i would pull the head and take a look .