just bought 1992 cbr 600 cleaned carbs and drained tank with valve open and gas in tank should gas leak out or should vaccuum be applied to get fuel out of tank i can not get bike to start unless i use carb cleaner

 

Vacume needs to be applied in order to release the "check valve" that allows fuel to flow. I dont know if yours is vacume or a pump or simply gravity, but if it's vacume then yes......vacume is required to get fuel to flow through.

 

I'm pretty sure the fuel feed is gravity only on the F2 models. could be wrong though. you MIGHT have something obstructing the fuel supply in the petcock, or the tank.

 

the valve has whar looks like diapham where vacuum hooks to but i dont understand why the bike runs on carb cleaner but will not run with tank hooked up with good gas i have a 2000 f4 but unfortunately they are nothing alike bike runs good and will rev up when using carb cleaner but will do nothing on tank all advise appreciated

 

Check the diaphram and make sure it is sealing properly. Check all fuel hoses. Pull the fuel hose off at the carbs and see if it is flowing there. If so..it's past that and you can then focus on the carbs.