I would suggest inflating the tire to about 10% less than the maximum listed on the side wall.

Thanks for the "real" and thoughtful responses, to those who took time to post them.

I am going to see how 30 and 35 feel, but it probably won't happen until temps get out of the 20's and 30's here.

The main reason for using a tire that wide is for comfort. I would start with 20 on the front and 25 on the back. I doubt that you will have pinch flats unless you drop one in a pothole.

Really???? I wasn't going to say anything, but I took the bike out today (couldn't resist and needed to settle this) and I tried a wide range of psi's between 30 and 50. At 30, the tires felt like jelly and I could hear the rubber squishing around below me. At 40, they rode almost as hard as they did at 50. At 35psi, they were almost there, but at 38, with no load on the rack, they were just right.

Overall, I am still a bit disappointed in these. I thought the ride would be a whole lot better with fats, but cornering and potholes feel about the same to me as they did with my much narrower and faster Nimbus slicks. If they LOOKED a little cooler (say, as cool as Maxxis Hookworms do) I would be OK with having plunked down $95 bucks for them, but they look kind of dopey and low-quality, to be honest.

Anyway, it's done and this chapter is closed. It has been a pleasure interacting with all of you as we trudged and toiled our way through solving this mundane problem. Thanks again.

Gosh, I thought I answered the question based on actual experience, very directly and without any sarcastic commentary. That will teach me...

Rims also play a huge part. I can ride at 75 psi with 23mm tires on tubeless Shimano rims, but less than 90 psi in 25mm tires on narrow Bontrager rims is awful. If the rims aren't wide enough you start to wallow before you hit the sweet spot for pressure. It sounds like that's your issue here.

I'm not sure of my rim size, but I will check it out today. I would agree with you that this might be the problem, as the tire appears to be literally shifting from side-to-side on the rim.

dwmkee: Obviously, yours wasn't the "sarcastic" response I was referring to. Damn, why is everybody always looking for a fight here?

I can def see pinch flats from those pressures. The OP is in NYC,which has roads as bad as ours. Also,he posted he didn't like the handling @30psi,doubt he'd like them in the 20's.

Then there's no sense in using those tires.

Related sort of. Running Geax 29x 2.3 tires on a 35 mm wide rim. Pressure varies from 35 psi( off road) to 45, ( pave) Are you using a front suspension fork? Just sit on the bike and use a pressure that makes the tires squish just a little. Wider rims will see a great benefit. Don't give up on them just yet.

I read an article years ago about car tyre width which concluded that tyres work best when the width of the tyre contact patch is roughly equivalent to the wheel rim width. With bicycles, you could never justify a rim as wide as the Big Apple, of course, but if the rim is too narrow, the tyre squirms around unless you run higher pressures, which would ruin the ride and defeat the purpose of the wider tyres. I guess Schwalbe could build a stiffer sidewall, but then it would be the same old story: lateral rigidity/vertical compliance, pick one.

It's pure coincidence that I've got a quote from Jeff Jones as my signature, but FWIW, the Jones City and Touring Bike specifies Velocity Blunt 35(35mm) rims for its Schwalbe 28(29") x 2.35" Big Apple tyres. Maybe that's your benchmark (although it doesn't suggest pressures).
Jones as a City and Touring Bike

I don't know if Papa Tom is still reading this thread, but I figured I could throw this in. I had a very similar experience when I purchased my 26x2.35 Big Apples. I inflated to a high pressure and was immediately dissapointed by the harshness. I repeatedly lowered the pressure and found out that unlike some skinnier tires, there is a huge difference in ride quality between a small range of psi. I settled on about 40psi rear and 35psi front, but I weigh about 210lbs. It sounds like you have it figured out now and I think you should ride the Big Apples for a while. These tires seem to "break in" and get better over the first few hundred miles. Also, mine are on a "vintage" steel rigid mountain bike of a similar era to yours.
-Bruce

Thanks, Sarah. My season here in New York is over for now (yes, I'm a winter whimp) so I haven't had a chance to play with my new Big Apples as much as I'd like to. As of now, I'm settled at about 38psi and we'll see where that goes. I weigh about 165.

I think what kylecycler and others have said about rim size is a big factor that I did not research enough, and that none of the bike shop people ever mentioned to me.

Being that I can't ride the bike right now, I'm spending a lot of time LOOKING at it, and I really think the Big Apples look dorky. I'd love to be able to remove the reflective strip around the sidewall. Maybe they'd ride better, too!

good lessons in the inadequacies of the written word, human behavior and misdirected animosity, if nothing else.

I have a mountain bike that I want to convert to use drop bars. What pressure should I run my chain lube at with 25 X 1.9" semi-lugged tires, and how can I best conceal my firearm for mostly paved singletrack rides in the jungle? Also, what direction should i wrap the bar tape if I have a fixed gear 3 X 12 drivetrain? Thanks for any responses that cannot be interpreted as sarcasm.

I would love to live in "your era". We have "Google era" now, and everyone seems to know everything. Yet, when it comes to specific answers, there is more confusion than help. What FBinNY said, is the only truly way to find your sweet spot for your needs. "Comfy riding tires/pressure" on one bike, may feel much different on the other. Firmness or overall comfort may also come from your seat, suspension seat post, front suspension fork, or even stiffness of the rims... Hard to help and say that THIS number will work great for you and on your bike.

I recently rode on NYC streets on 32mm tires with 30 psi. I didn't bottom out, though it was pretty risky. I'd say you can go well below 30 psi on your new tires without risk.

IMO 30psi in a 32mm tire on NYC's potholes streets is pushing the limit. Probably fine until a pothole suddenly appears out from under a cab at 20 mph or more. Plus, it's going to cause more drag than necessary.

Optimal tire width and pressure is about balancing, ride, rolling resistance, rim protection, handling and traction. With that many variables, no simple formula is going to get anyone closer than to the right ballpark. Afer that it's about riding and making judgement calls based on priorities.

For some perspective. BITD whe we were riding 3-speeds with 26" tires (35mm or so wide) we rode at roughly 35psi, until better tires were introduced which made 50psi possible. IME, once we tried 50psi, we never looked back.

That was my point, though you put it better. I don't plan on doing that again. I measured after the ride and then said oops. But I got away with it. I dare say [MENTION=137127]Papa Tom[/MENTION] can get away with it with his tires, and maybe with less.