i have a 2002 banshee,it has a ported top end,.03 over,fmf pipes,boost bottle,boysen reeds.it idles fine and pulls ok off idle,but falls flat and won't rev.carbs are cleaned and it has 320 main jets in it.still has the tors carb tops on it.i am in michigan.also using amsoil,says to mix at 50:1. is this ok ? thanks