Judd

Ok, problem i am having along with another friend who is starting to have the same issue, when we come down from a stoppie, or if i come down hard from a coaster, the bikes idle drops like its going to stall, and can take 30 seconds to a minute for it to jump back up. sometimes when i rev it it revs fine, other times it sounds like its loading up. changed the fuel pressure regulator last year when it was having a similiar problem, checked it and its fine. just trying to see if anyone else has had this problem and what they did to fix it. any help is greatly appreciated.