I've built a home CO2 carbonation system but I have a question about carbon
dioxide flow (see pictures below).
Q: How do I get the tire chuck to work since it won't flow w/o the stem?
Q: Even if I attach the hollow tire valve directly to the CO2 hose, how can
more than the headspace of the bottle FLOW into the bottle?

I forgot to list the URL which said the C02 has to flow:
"Carbonating at Home with Improvised Equipment and Soda Fountains"
(http://www.truetex.com/carbonation.htm)

If I leave the inside of the tire valve in (see white cap in the
pictures at http://yfrog.com/13homec02system5jx), the CO2 carbonization
does not get to the 50psi you'd like that is in the bottle headspace; but
at least the tire valve attached to the hose is operated by the center stem
in the tire valve attached to the soda bottle cap.

Yet, if I remove the center stem from the tire valve (see the red cap
in the pictures at http://yfrog.com/13homec02system5jx), I can't get the
air chuck to operate (since it depends on the center valve to open up).

I'm thinking of just attaching the red cap open tire valve stem
directly to the carbonization hose but even then, I can't, for the
life of me, understand the article's wording that says the CO2 needs to
"flow". (Specifically it says leaving the valve stem on the valve "does not
work because the process requires a continuous flow of CO2 into the
bottle via an open connection".)

What I don't understand is where is the continuous flow into an "open
connection"?

If I clamp the red bottle cap onto the yellow hose (thereby eliminating the
air chuck), it's still a closed system, isn't it? Where does the "flow" of
C02 occur (except momentarily until the headspace of the bottle is
filled to 50psi or so)?

I'm sure I'm missing something simple ... I just do not understand
what I'm missing and I'm hoping someone can point me in the right
direction.