RVF400 starting problems if bike is left for about 12 hours

Hi guys, this RVF400 is testing my patience!
Symptom is : I can start the bike IF I take out all spark plugs, clean them (correct 0.6mm gap) and make sure the cylinders are clear of fuel (by blowing compressed air down and into teh cylinders for a while until there is no fuel smell).
The bike then fires straight up. If i turn the bike off and go to start it the next day, it floods? I used full choke and no throttle....flooded. I cant then put on full throttle and no choke and clear the cylinders. If i leave the bike for a day or two or even three days, still nothing. Removing the plugs will show all wet plugs (wet and slightly black).
The whole process continues with removing all 4 plugs and cleaning and drying the combustion areas (i can get by with leaving the plugs out for a day and then it will also work).
If i clean the 4 plugs and don't clear the chambers of even minor excess fuel, it wont start. If i continue trying to start the bike, there is backfire from the exhaust.
The carburetors are all cleaned with a complete dismantle and overhaul and all floats were checked.

Any suggestions?
I was wondering if i could turn the fuel tap off and let it run out of fuel and that would reduce teh chance of flooding? I know then the carbies would be empty and would need re-priming but that mayu be faster than removing all 4 plugs every time (for those of you who have taken the front plugs out, the damn radiator is a nightmare to get past).

Bike starts and idles well (when it can start). If it is warm and has been started, it will start easily. If it is left about 12 hours, it can be hard to start.
I tried 1/2 choke, 3/4 choke etc and no luck especially when flooded .

Could there be a valve clearance problem? If so, would this affect the idling as that appears normal.
I could try turning off the fuel tap when it sits overnight and see what happens ( i don't think that the fuel is overflowing from the carbies though)?

Many thanks in advance.:(

I'm not very knowledgable on the subject of carburettors, but could it be a carby tuning issue? Have you tried adjusting the mixture screw at all? Was the same thing occurring before the carby rebuild?

Since the carby rebuild , the bike runs a lot better with better idle etc but it did have similar starting problems before the rebuild.

i also had this issue or similar on my VT250 when it would start fine after cleaning the plugs but wouldn't start the next day due to flooding.

my issue was the petcock was installed wrong and fuel was somehow dripping into the cylinders overnight.

since my bike's petcock is vacuum operated, i leave the petcock on all the time and it needs the cylinder vacuum to pull the diaphragm back and start the flow of fuel.
for some reason the spring holding the diaphragm back was reversed so it would hold the diaphragm open rather than closed. This would let fuel flow freely into the carbs and presumably overflow (despite the fuel vavle/float) into the cylinders

Where are you located? if i were you i'd trace from the fuel tank back to the cylinders and check for any issues. mainly petcock and carbs

Quote:

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Originally Posted by gre03

i also had this issue or similar on my VT250 when it would start fine after cleaning the plugs but wouldn't start the next day due to flooding.

my issue was the petcock was installed wrong and fuel was somehow dripping into the cylinders overnight.

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Thanks for that info.
Can you please let me know what you did to fix the petcock (did you get a new one and with the old one, did fuel spill out of the petcock all the time causing flooding of the carburetors?). I would think that fuel constantly coming out of the petcock would be stopped when the floats in the carburetors rose and closed the valves?

as above mate.
are you in vic?