How dirty is it, and how far do you want to go w/ disassembly?
You could open it up and use some carb cleaner, then use some pipe cleaners, and then more carb cleaner or compressed air to blow out everything.
If it is really bad I completely dissemble them and dip them in a gallon can of cleaner that I have. Stuff works great, but you cannot leave it in there for long(hours), or it will dissolve everything. After you take it out, you must rinse it off and then clean everything (pipe cleaners nd cleaner or air).