Just did this on friends xs650.
remove slides
remove bowls
remove main jets
remove washers under main jets
look at the emulsion tube (part the main jets screws in to)
you'll see a little slot on one side. make mental note. A pin from the casting extends into this slot.
grab a small dowel or maybe a chopstick and use it as a drift to
push the emulsion tube out throurh the top of the carb(where the slide was) you may have to tap gently on the stick but wood won't hurt the brass or pin if you happen to snaf it.
That's it... clean up tube inside and out and clear all the small holes clean the casting on the inside and maybe remove the small jet under the rubber button to make sure passage between it and main jet is clear. I used a pipe cleanet.
Wen you put it back together, the main jet emulsion tue should slide in easily. Be mindful to fit the slot in the side over the pin in the casting.
Don't forget the washers when you put the main jests back in.
Don't forget the small tab on the slide diaphragm wne you put the slides back in. Use a little vaseline if the diaphragm doesn't want to stay in the grove.
-Duck