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At least that's what I think it's called. My '92 CB750 has exceeding simple carbs, from what I hear, but my idle and performance have steadily decreased since I bought (and fell in love with) the bike over two years ago, so I figured a carb rebuild was in order. When I got the carbs off and torn apart, they looked really clean inside, no carbon funk built up on carbs or jets, no rub marks, no torn diaphragms. The O-rings look pretty tired but that's to be expected. The needle jets were kinda ganked up but not actually dented in, so that was better than I expected. One needle jet is shiny on one side, like it was somehow rubbing on something, but I'm clueless as to whether this is damage or just weird wear pattern. Didn't wear down a spot, just wore down to shiny-ness on one side.
So....
Should I have it cleaned in one of the soundwave tanks? I have no idea where all the orifices and holes and stuff in these carbs lead to. The price to have it ultrasonically cleaned and the basic o-rings replaced is less than the the price to buy the o-ring kits with ALL new needle jets and all the brass needle parts for all 4 carbs.
Anybody been here? Anybody had to rebuild carbs that just weren't all that bad? I have everything apart and the carbs torn off the rack, and I have a different bike to ride while I do this, but I honestly have never been in this situation, I prefer to do my own work, and I'm not scared to go even deeper if I need to. I want my beloved CB750 running like new, I just don't know what to do from here.
Any help deeply appreciated...and thanks....

Strip carbs and use aerosol carb cleaner first. If all the passages are allowing carb cleaner through you probably don need ultrasonics. If anything looks slightly blocked ultrasonics will probably clean it.
I've tried it and it works great, even on really nasy carbs
If you have a bunch of carbs to do, look on e-buy for tattooing equipment, the ultra sonics are much cheaper (and about he same ) as the ones sold for carb cleaning.
PJ

The '91 on Nighthawk 750's run lousy when the carbs are out of sync.

That may be at least part of your problem. My buddies '99 had a rough idle and hesitation off idle, and it all went away after a carb sync.

My '91 is starting that and I am going to sync them this winter.

I synched 'em a few months back. It was good to know they were pretty much spot on already, but it didn't help the bad idling, hard starts, and occassional shutoff when coming to a quick stop. Or the falling gas mileage.

BTW, I ponied up for the TwinMax carb synch tool and it's very good. Easy to understand and easy to use.