Searched high and low, cant find
 

I have searched everywhere but it seems that the psi is never listed. I am looking for a 700x28c clincher gum wall road tire that is "rated" on the side wall at up to 110 psi. It seems like all the gum walls I find are low pressure or if they do list it as high pressure then it is only rated up to 80psi. I hate the squishy feel and like running my tires at 110psi.

then run 23s or 25s. No reason to go to 28s if you are going to run them at silly pressures over 100.

I have an Avenir 700x28 beaded, but it's blackwall.

My wheels are too wide for a 23 or 25. I used to have 25's but they look funny and the sidewalls look spread out

Have you tried looking at Panaracer Pasalas ? The 32's are rated at 95psi. the 28's are probably higher. I'm not sure why you would run them that high, a little lower pressure may result in a more comfortable ride with no loss in speed.

You might want to consider that with a wider rim, say in the 22-25mm range, that your tire's air volume is increased, thus the tire needs less air pressure to resist any kind of pinch damage.

Also, with the more-vertical sidewall disposition that wider rims afford, the sidewall doesn't arc away from the edge of the rim as much, so the tread doesn't fall toward the rim as much from loading. Again, this further reduces air pressure requirement.

And further, the more-vertical sidewalls make the tire laterally stiffer, such that a more-direct feel is effected during transient cornering adjustments.

But pressure requirement is firstly proportional to the weight load. For reference, I and my bike are averaging about 185lbs lately, and with 28mm tires (actual width more like 26mm on 22mm-wide rims) I find a pressure in the very low 80's to get the job done with minimal pinching likelihood, a smooth ride, good grip on hidden gravel and longer tread life.

And as for the "gumwall" or tan-side tires, there are very few choices these days. Vittoria makes a primo racing version, but only in 23mm.
Panaracer Pasela seems to be the go-to tire for most vintage enthusiasts who don't mind (or who prefer) it's hybrid-style tread cap.
I'm currently running out my supply of tan-wall "28mm" Avocet wired clinchers, and will probably fall back on my stash of brown Continentals when these are gone.
Then again, there will likely always be a market for (and thus a supply of) the Grand Bois and similar higher-end tan-side offerings, which surely are rated for max pressure.

you can run 25s on rims with up to 17mm interior width, though I bet you could go up to 19 with quality tires. Have a half cyclinder profile is now preferred to the lightbulb profile of yesteryear. It corners better and is more aerodynamic.

The wheels im running are 23mm exterior width with an interior width of 17.6mm

FWIW, I ran 23mm Michelins (which seemed generously-sized to my eye) on a pair of 25mm-wide Mavic Module-4 rims back in the late 1990's.

I did all of my hill-loop training on that setup for about two years up in the Santa Cruz Mtns. Never had any problem, and the 25mm-wide rims appeared to protrude just a hair beyond the inflated width of the tires. Cornering felt extremely firm and precise at what I remember being about 95psi for my almost 190lb bike+rider weight.

I built those wheels myself onto a pair of 40h solid-high-flange tandem hubs that I narrowed to 128mm, and with all those spokes and the wide rims plus the vertical sidewalls, no wonder they felt solid! I still have 'em.

I have also run 20mm tires on Super Champ 58's that were 22mm wide externally and had contemporary bead hooks, again with no problems but at a slightly-higher pressure for sure.

HED's newest alloy rim is fully 25mm wide externally (19mm inside, iir), with no warnings against using 23mm tires. These wider (although only 25mm high) rims are supposed to be much more immune to frontal drag caused by crosswinds.

In the pioneering spirit, and at the opposite extreme, I raced MTB for years on 45mm tires mounted to rims only 20.5mm wide! Again, no problems, and at around 45psi.

No one asked the original poster it appears… but do the wide rims have a hook bead section? If not, that is the limiting factor of tire pressure.

I am running the H-plus son Tb14's.

http://hplusson.com/products/TB14

You can run a 25 no problem on those. I wouldn't hesitate. You may want to try the vittoria 700x27 roubaix tire if you want some added cush. If I had the room on my road bike that is what I would ride at about 90 psi and I am a 185 lbs rider. I run my 23s at about 95 to 100 psi currently.

Found some!! They are the Panasonic Panaracer Pasela PT. I found them with gum walls in 700x28c and they have a pressure rating of 105psi. They were cheap too..

http://i30.photobucket.com/albums/c3...psc3939608.jpg

I was going to suggest the Pasela. The puncture-protected version used to be called Tour Guard, or TG. They may have changed the name because they recently changed from aramid (Kevlar) to some other material, claiming aramid was getting too expensive. They work well. The Pasela also comes in a cheaper non-PT version. Also in a "folding" version with aramid edge cords instead of steel, lighter but more expensive.

I have 28mm TGs on my commuter/utility UO8 with Sun M-13II rims, a somehwat narrowish rim.

FWIW, 105psi and 110psi are equal, more or less. Your pressure gauge my be off by that much, and when you pump a tire up it will hold pressure like that for only a few days at best before your 110 is down to 105. You likely would never notice the difference between 105 and 110 regardless of what its rated pressure is. The 25mm version is rated at 115psi, and though it may not fit your rim as well you probably couldn't tell the difference riding.

This is sort of a semantic argument, but those tires aren't gumwalls!

Call them tan-side or skin-side, but gumwalls have thick rubber protecting the sidewalls from extended periods of exposure as well as from abrasion. Gumwalls usually are a feature only on cheaper tires where weight is not the primary concern of the customer.
The skin-side tires are more for enthusiasts, who A) put on the miles, thus wearing out the tread before the sidewalls are compromised, and who B) are conciencious about their bike's handling and storage, to thus preclude, again, compromising the sidewalls.

That the gumwalls are generally cheaper jibes well with a typical commuter bike that may be left locked up outside, also subject to the theft of any premium components if not of the entire bike.

As for rated max pressures, this is typically a very conservative number, but is appropriate in that the effect of age lowers the reliability of the casing. Thus a young tire can safely be ridden at higher pressure than a tire with significant aging, perhaps higher than as rated, and as these Paselas are particularly prone to the effects of aging when kept in service for longer periods.

Any 23mm or larger tire is fine on those rims. That's the whole point of wider rims.

I have two wheelsets with these rims, but I use wider tires. I'm a fan.