Another Tire Pressure Thread
 

Sorry. I can't seem to find time to search existing threads for my answer.

I just purchased my first set of fat slick tires - Schwalbe Big Apple 26" X 2.35"s to be specific. My first mistake was inflating them to 50 psi, at which they don't feel a whole lot different than the 1.5" Specialized nimbus tires they are replacing.

I've heard these can be run at as low as 30 psi. I am riding a 1996 vintage steel GT Outpost mountain bike and I weigh about 165 lbs. My rear rack carries about another 3-5 lbs worth of "stuff," I'd estimate. I will be riding 98% on concrete and the rest on packed dirt and maybe some rocks.

Can somebody suggest a good tire pressure without referring me to another "chart" or conversion guide?

I'd guess something between 30 and 50 psi.

I guess I walked right into that one, huh?

What I'm looking for is someone who has used these and can share their experience.

Unfortunately, that's my best guess but you are on the right track asking for random guesses here. It's impossible to find out first hand.

I used to ride Big Apples on my Fargo. I rode almost entirely on paved surfaces and I think I kept pressure between 40 and 50, definitely toward the higher side of the range but not at the extreme. Lower pressure was more comfy but slower when you wanted to go fast..

OK, let me rephrase this.

I'm trying to find a comfortable inflation pressure for these tires while avoiding under-inflating and damaging them.

Does anyone have any experience running these at the 30psi minimum, or am I just going to keep coming back here for AnkleWork's sarcastic bullsh-t?

According to the chart (yes I heard what you said about charts) It sez 30-55. So. Why do you think/ feel 50 was a mistake?

Truly, you're going to have to play around until you find what's right for you.

Aww, but I'm on your side. We all have good reason to avoid first-hand experiences.

I guess you'd have to have followed my thread on this topic in another forum to have the full picture.

Essentially, I bought them expecting a nice, cushiony ride in contrast to my 1.5" slicks. As I inflated them for the first time, I noticed that they felt kind of mushy to the touch, so I kept pumping until I hit 50psi. At that pressure, they didn't ride all that softly, so I was immediately disappointed. Several people commented that I should try running them at a much lower psi, but none of them professed to have any experience with this specific tire, so I set out to find someone who had.

I've seen the charts and I've read the sidewall. After 45 years of cycling, however, I've learned the hard way that, many times, the minimum inflation listed on the tire is a recipe for endless pinch flats, sidewall cracking, etc. So I thought, perhaps, someone could shed some light on what might be new technology allowing tires to be run at lower psi without damage, etc.

Of course, I intend to experiment, too, but what are these forums for if not to seek input from others?

At 170lbs,on my Big Dummy,with about 40-45lbs of gear,I run my 2" BA's at 55fr/60r. Rides good. Below 50 on the back I can feel it get wallowy.

As I said in the other thread,you should play with the pressure to see where you like it the best. No tire can give both a plush ride and sporty handling.

You basically answered your won question. 50psi feels too high, and you've read that they can go as low as 30psi. So don't listen to folks who can't know what you want or need.

Instead listen to your bike, and your body's senses. If I were you, I'd start at the "too high" 50psi, and drop pressure in 5# increments riding at each level a while to get a decent sense of how it handles, then moving on. When it gets sloppy, or you feel seriously at risk of bottoming out on hard bumps, go back up to the last decent level.

BTW- use a similar process to find the right pressure for front and rear tires, which likely will be different. Also, be aware that "best" pressure will vary based on road/trail conditions so don't lock yourself into the idea that there's only one best pressure.

So you see how worthwhile my initial response was: you don't seem to acknowledge there is anything between 50 psi and 30 psi. Stunning insight: you could try 40 psi, then either 35 or 45 psi depending on your desire, and etc. In four iterations you'd have the range down below your threshold of perception.

I'll be serious first: what FBinNY said. (that's a period) and not to minimize any other previous posts of course. You will get a lot of opinions, but especially with tire pressure there are way to many variables and you are already in the ball park. With you years of riding you must have tweaked the inflation pressure of your tires a bazillion times until they felt just right for the terrain and your style. In my case I went from road bikes directly to mtb on snow - now there was an extreme example of tire pressure education. On the snow my 2.3's felt good at very low pressure, as soon as I hit the parking lot I thought I would destroy the tires from being so ... flat.

Now to your quoted comment: kinda thinking the forums are for educational feedback from other members, useless attempts at helping, self-entertaining responses to your posts, some fishing to see what kind of smart responses we can get, and a little fun trolling. :innocent:

Ya, you did walk into that one from AnkleWork. :thumb:

One last comment. I'm from an era when you used to ask a question just for the hell of it, even if you already knew the answer. The point was to strike up conversation, maybe make a new friend, give some poor shy dude a chance to show off what he knows, or at the very least, pass some time while you're waiting for something more stimulating to happen. If the weather was more conducive to riding right now, I'd have been outside all afternoon playing around with different pressures and I'd have settled this hours ago. I chose, instead, to try to engage some other cyclists in a light conversation, and I guess that isn't the way things work anymore.

Also, I'm fully aware of how lame my question was, but at the same time, I've learned more in my lifetime from putting questions out there than I have from NOT doing so. Anyone who finds my posts silly or not worthy of a legitimate response is welcomed to ignore them. I don't think ANY of us need to be censored or ridiculed by any of the self-appointed relevancy police that troll these forums.

Papa T. CHILL. There's no sense in getting your feathers ruffled.

Just as you say others can feel free to ignore your question if they think it's dumb, you need to feel free to ignore any response that might otherwise bother you.

To start out try 40 in the rear and 30 front. When I had these I would run 60 rear and 50 front. But I am much heavier than you and I was concerned about speed. At lower psi they were quite cushy, I'd do that for very casual rides in the neighborhood.
With your weight I don't see any problems with pressures down to 30 (possibly even lower) if you are more concerned with ride over speed. I have switched to Contis 1.6 slicks for the speed but think these are nice for a cushy ride.

And then there's this to consider:

Just a comment on your experience with minimum inflation. On my MTB I run my tires at pressures below the minimum recommended for some terrain with no issues. Maybe tires are better now. Back in the day I never went anywhere near the minimum I was always at the upper end. After reading and talking to people about the traction benefit of low pressure I have been running my MTB off road at much lower psi than before. I will say that speed does suffer a bit for traction, but it's worth it for not only traction but a bit less shock to my body too.

So, let's see. How many Chain lube threads? or Chain length, stretch, or skip ones? How about all the repeat wheel building, spoke gauge, dish, offset rim, and whatever threads?

I could go on, and list dozens of topics that have been rehashed to death, so what makes a tire pressure question out of bounds, even if you think it's dumb?

Fact is, that probably 90% of the threads wouldn't exist if everyone invested the time and effort to look up prior ones. But if everyone looked up instead of posting, the number of threads would dwindle. Less new threads, means less posts and less views. Since BF depends on ad revenue, the last thing they need is everyone being diligent and looking stuff up, or responders staying 100% on point and not adding their 2 cents once the question is answered. it certainly doesn't need people veering off on tangents and generating tons of views of stuff that doesn't matter.

So, next time someone asks a really stupid question, or stirs up needless controversy, thank them for doing their part to keep this forum alive and interesting.

I would reduce pressure by 5 psi increments and stop at that pressure where getting out of the saddle feels bouncy. I suspect it will be about 45/40.

My, my, FB. You sure do read a lot into small comments. If only you would read the questions as carefully before posting your repetitive and extensive answers [for which I am very thankful =)].

In point of fact I was reminding the respondents here of how the OP had shaped the conversation from the very first sentence. Please don't be offended that my approach is different from yours. I seek to answer the questioner, while you answer the question.

http://www.bikeforums.net/bicycle-me...re-thread.html This doesn't go wide enough, but you may be able to extrapolate a decent pressure.

+1. Like the OP, I'm not very heavy (~155 lbs). And since the skinniest tire I run is 28mm wide, I am frequently at or below the recommended minimum pressure in the front tire. It doesn't feel as fast as tires pumped up to the max, but I'm not sure that I actually lose all that much speed, and feel much better when I arrive at the end. :thumb:

Hmmm.... How about as a rule of thumb....

Put away the pressure gauge.
Use your thumb.

And fill it up until it feels about right :thumb:
Then ride your bike and enjoy ;)

Drop down to 30 psi and see how they feel. I'm guessing 25/30 (F/R) is probably about right. My MTB has 2.35in tubeless tires that I run at 20/25 psi (30 psi min recommended, 160 lbs rider), without any issues. If you're a lighter rider, you basically have to go below the minimums, especially in front. Even at 20/25 the bike doesn't feel any slower than at 30+ psi, and the same for my road bike (75 psi on 23mm tires).

Pinch flats are more about riding style than tire pressure. I tend to be a fairly light rider, unweighting the saddle etc, and don't have many issues with pinch flats. If you're getting pinch flats, then definitely raise the pressure, but at some point you quickly start sacrificing ride quality.