There is a drain hole under the rubber bit. if you undo the allen bolts holding the cap on, you can remove the whole unit to expose the hole ( its at about 10 o clock when sitting on bike ). If that appears to be clear you can carefully blow down it , don't use a high pressure blow gun cuz you might damage the pipe where it goes THROUGH the tank. If gentle blowing doesn't clear it,wait until you have less than a 1/4 tank of fuel, remove seat, undo bolt at front of tank and lift tank up to about 45 degrees and support with a bit of whatever ( broom handle etc ) you will now see 2 small rubber pipes attached to bottom of tank, one of them is the water drain and the other is the breather pipe for the fuel tank, you can safely disconnect both of these pipes with the fuel cap open you should be able to blow through both these pipes, ( through the tank AND blow down the rubber pipes that you have just disconnected ) when you find where you can't blow through, get a thin piece of wire and gently attempt to clear blockage. Hope this is of some use, Fraser