Ok so I cleaned two of mine used the ever-clear method mentioned by Morandir but didn't let them soak for more the 4 hours. I cant help it im impatient didn't do any water flush just let them air dry for a few days. First try ok so there not brand new but they took
juice really well but my draw seemed clogged. I killed one smilo already pushing something to big
through it. Today I used a small long paper clip and using a drilling motion I gently pushed it through and got allot of black gunk out man they hit like new again

So moral of the story maybe let them soak longer not sure about the water flush these are hard to dry out and use small paperclip to clean center hole. I dont get the crackle and sizzle my new smilos give but they do work really nicely.