Dual tire inflation from standard compressor?

If this is to replace the chuck on a tire inflator hose/line?

1) buy the duel chuck that you want, they do sell one that will hold itself on to the vale stem.

2) Go to a place that sells pipe and fittings (Ace, Home Depot, Lowes) buy a brass nipple of the size to fit chuck then a reducer coupling to 1/4" hopefully in brass too.

P.S. Might even find a reducer bushing that would do the same as #2

Yes, that's what I mean. The portable compressor I have raised the pressure in my front tire from 50-60psi in about a minute. Certainly not too bad.

I'm not going to carry a big compressor with me on the road and I can't reach the inner tires with the screw on attachment I have now. Just looking for the best option.

What exactly do you mean by a "standard car/truck portable compressor"? If it's one of the little inflators, particularly one that plugs into a lighter socket, you really won't care to be holding the dually chuck on the valve stem for the many minutes it will take to fill the tire to pressure with the noisy little gizmo next to you making a racket. With some of these little compressors and four dually tires you could literally be there for hours if you need to add a lot of air.

With that said, tire inflation chucks generally come with 1/4" NTP female threads, which you have to attach a quick connect or whatever to. 1/4" NTP schrader valves do exist and are not too hard to find online (and probably elsewhere) for reasonable prices.

Search under "dual tire inflator" and buy one off the net, or get a t-fitting and some other parts at a hardware store and make one for yourself, probably cheaper.

Miles

Personally all my ari equipment has quick connects, I would do the same with that.