hmm
Had a friend who's carb would not stop overflowing fuel, his bike was fine one ride and the next it began to overflow as soon as the petcock was opened. If your float was out of adjustment I doubt that this problem would manifest all of a sudden. My wife's bike did the same thing, but was a different issue:
My wife's bike had a "bad" needle and it would not seat correctly subsequently if overflowed fuel. I bought a new needle and the problem was solved.
My friend's bike had a similar but slightly different issue, his needle seated/sealed just fine however the recess/race that the needle seats into was threaded into the carb with an o-ring between the recess/seat and the carb body. He replaced the o-ring and it worked fine. We figured this out on the trail and used chapstick as a temporary fix to help the o-ring seal.
I have also had a piece of crud on the needle's head preventing a seal....now I run a fuel filter on both our bikes
Both of these problems were pretty easy to diagnose by removing the float bowl, opening the petcock and moving the float up and down to see where/when fuel was coming from.
good luck!
