No fuel

[Niedernut]

The facts:
I have spark from the new plugs/new wires/new caps and they are on the correct pistons.
I have the clutch cable & choke cable brand new and working beautifully.
Carbs have been rebuilt and cleaned out. I have rechecked the seals around the input and output of the carbs and they are tight and on well.
Piston rings are new and provided the necessary 'pull'

What is happening:
No fuel is getting into the engine to start it up. I don't think it's a problem with the engine sucking gas as much as there is a block on the gas, preventing it from being drawn in. I am sure the tubes are right on the carbs, and I know the gas is turned on. I am worried that the petcock (I think that's what you call the part with the two large tubes attached to it) might be my problem. I don't know that it is permitting the gas flow. Does anyone know other issues it could be? Advice to get it to pull fuel into it? anything?

[Volker_P]

Open a screw at the bottom of the floater bowl. If fuel spills out (at the main stand in case you have the small hoses on the bowls) you have at least fuel inside the carbs. With a transparent hose plugged at the bottom of a floater bowl and bent upwards, then again opening a screw you may get an idea of the fuel level. I think it should be close to the seal plane.
The petcock has a filter screen inside the tank, for a first rough test you may try to blow it through and/or leave a bit of fuel spilling into a bucket to estimate whether that should be sufficient or not. Some models have an additional vacuum shutoff valve sitting somewhere on the carbs which does not open when the vacuum hose or diaphragm is damaged. It only opens at vacuum i.e. when cranking. It is safe to bypass it or remove it completely.
A CB650 needs a lot of fuel to start, choke must close completely and twisting the throttle a few times before pressing the starter again also helps. With the manual idle adjustment open too much, it will hardly start. Turn it out until it looses contact, restore contact and one further turn in should be all right.

[cb650]

The 81/82 (CV carbs) had a vacume shut off also.

[Niedernut]

I'll check that shut off valve you mention. We are getting gas out of the tank, so I don't think it's the petcock there. There is no gas in the bowls of the carbs, so fuel is running into a problem from the tank to the carbs. I can only assume that its the pump thingy at the top of the carbs where the tubes connect. It's the metal round part that has two large tubes coming off and a small one or two on it (ones just a breather tube). I have seen it called a petcock on BikeBandit and I have seen it called a pump on eBay, so I don't know the exact name of it.

Regardless, I like the idea of clear tubes, though will have to find some. I know it's gotta be a simple fix. To be this close to the end and it not start is such a downer!

[5.4L to Freedom]

be mindful of your fuel hose as well, if you take a look at the 82 nighthawk thread i have up it may shed some light on your issue. Also, cant recall at the moment check and verify your petcock is working 100%

[cb650]

I remove the vacum shut off on all my bikes. Something less to go wrong.