Sticky Cylinder slides and a flooded engine

Hi guys,
a few of you might have remebered my post alittle while ago about my speed problem. Well my bike actually broke and wont start now because it turns out the cyclinders in the carbs where sticking and flooding the engine with gas. I have a 1979 kz750B
and im tring to decide what best to do. A mechanic told me what the problem is and his answer was to spend over a 160 bucks just to clean the carbs. But I have an extra carb set, but i think im just going to open the carburetor and clean it with a rag wiping away all the gas resadue, then lube up the cyclnders before i put them back in. The engine also flooded with gas and a gasoline odor comes out of the oil so im going to change the oil because that probably thinned it out. So what do you guys think, can i just clean the inside of the carbs with a rag? and is all i have to do is lube those cyclnders so that they move up and down more freely?(and what type of lubrication should i use) Any input would really help
thanks

Thinking carbs do need cleaning.

Also suspicion float needles leaking and overflow circuits possibly clogged.

Is imo a bad idea to lube the throttle slides. If slide is scuffed, could use some very fine wet-sand-paper to smooth out the scuff marks.

Rags leave lint. Would use spray-can carb cleaner and compressed air. Always wear eye-protection, which means protective goggles. Because the spray always backfires into your face and eyes. Always backfires -- every time.

Should also replace the oil filter with a brand-new oil filter.

Good Luck!

you saying its bad to lubricait the sides of those cylinders?, i thought you wanted them to move up and down freely?

You do want them to move up and down freely, that's why you don't want to put oil on them

Oil is sticky and will make the slide movement sluggish.

so what should i do beside cleaning them, or how do i check for "float needles leaking and overflow circuits possibly clogged."?

Slides seldom stick because the bores are dirty. Most of the time it is a mechanical issue. The carburetors do need total disassembly, cleaning and rebuilding. If the carbs have been sitting unused for a significant amount of time, gas can get in the bores if the carbs were sitting on a shelf and this gas will cause them to freeze up in the bore but if the bike has been used, more likely a mechanical issue. A lot of times, folks force the carbs up using a screwdriver to pry the slide diaphragm pistons and this creates burrs on the bottom edge. The needle jet may also be deformed or the jet needle bent or the throttle pivot rod can have crud or rust where it pivots or the throttle butterflies can have a bunch of crud where they seat in the venturis that causes the bellcrank to not move smoothly and not allowing the pistons to come up when vacuum increases, etc etc.