I've had that happen to me on every thing from a lawn mower to my cars. You have trash in your bowls and in the needle seat. 9 times out of 10, I have never had to take my carbs apart.
There is a drain screw or bolt on the bottom of you float bowls. Crack those open and let the fuel drain out. If you have a vacuum type petcock, don't over heat your starter trying to get your bike to start. If you have some other way of supplying fuel (a bottle with some fuel hose and a double nipple to connect to existing fuel line)that would be nice. If not, whirl the starter like you were going to start normally. Let is sit for a minute, then run the starter again. You can repeat til your float bowls are full again.
The bike should start. It should run better. If it's still running a little funky, repeat the process again.
Sometimes carbs have to be totally rebuilt to correct any problems. I find that I've only had to do that when there was a lot of fine silt that got past the filters or a bike has set up for a long time.