Although taking the float bowl off was a good way to start, you really need to take out the brass jets to clean them too - all you need is a clean screwdriver of the correct size. Also, remove the float hinge pin, and remove the float, together with its needle valve which will also fall clear. If you see a spring loaded screw in the side of the carburettor, take this out too, but first count how many turns it takes to screw it fully in before doing so - that way you can reset the screw at reassembly time. I use an aerosol carburettor cleaner which is a remarkable solvent to clean any debris away, together with my compressed air line.
John
May 2009