nc29 fuel problem

[superfour1300]

hi guys
my mates son has a nc29...i have one myself but know very little about them..
his problem is as follows..
he recently bought his bike and like my own had been stood for a few years..
he took off the carbs and removed float bowls to clean the jets etc..
he has now noticed that sometimes the bike is very hard to turn over after been standing overnight.he believes that the no1 cylinder is filling up with petrol.he is worried that it might even hydraulic lock on him..he isnt sure if it was doing this before he removed the carbs
he turns the fuel off at night and it still happens..
when he disconnects the fuel pipe from the tank with the fuel turned off no fuel comes out of the tap..but if he turns fuel on it does...
does these nc29,s not use a vaccum fuel tap..only fuel runs when engine is cranked over?
he hasnt checked the fuel pump yet...if the fuel pipe is disconnected from the carbs should petrol flow from the fuel pump only when engine is turning over or will it run through the pump even when the bike is not running?
even if the float was sticking in that no1 carb should the fuel not run out of the overflow and not run into the engine?
when it does run 9 times out of 10 the no1 cylinder isnt running..downpipe always cool...he removed the plug,turned over engine and fuel pissed out of that cylinder..
hope this makes sense...

[amorti]

Sounds like a sticking float valve. Have him open it up again, and pop the float valve out and give it a proper clean.