Sincitycycler

One pleasant side-effect of buying orange Vredstein Fortezzas for bling value is it turns out that they while being a tad heavier that a hard-core race tire, they are strong, flat-free composites capable of holding up to 160psi!

I use 140psi in back and 125psi in front for my Jr. Clydesdale 195 lbs.

What y'all use?

thewalrus

115 to 120, the tire is a Specialized Mondo kevlar bead 225 gram 23mm. Rating on the sidewall is for 115 to 125 psi. At 120 it has a pretty narrow road contact patch, I weigh 163.

Machka 

Ummmm .... you don't have my numbers up there!!


My rear tire psi would fall into the category: 90-100 ....... nice and comfy.


(160! - yeah right ... like I want to be riding on something with all the cushioning of concrete.)

jschen

Running Specialized All Condition Pro's, 23mm. Sidewall suggests 115-125 psi. I generally aim for about 110 psi. Bike and rider together are about 165-170 lb. I'd be fine with lower pressures if I weren't prone to forgetting to check my tire pressure for a day or two sometimes. Getting the pressure up a bit is insurance against a bit of forgetfulness.

nitropowered

I run tufo cs22 specials and run 110 front, 120 rear. Well, thats what I pump them up to when I get around to it. These are rated to 175. I couldn't imagine riding on that pressure.

aluckyfiji

100 front 105 rear... I guess I do not like the rock hard ride...

dlavi

100 front and rear on Michelin Axial Carbons (or whatever they are called now)

simplyred

..

alanbikehouston

Correct PSI for any given width of tire is based on the actual measured width of the tire (not the "marked" width) and the combined weight of the rider and bike.

So, I get good results with 32mm tires at around 70 PSI front and 80 PSI back. With 25mm tires, I run about 90 PSI front and 100 PSI back. A rider who weighs around 120 pounds could ride on 25mm tires at 70 PSI front and 80 PSI back...that lighter rider would get the same tire profile and contact patch that I do.

The PSI rating stamped on the tire is a "safety" rating. Most 25mm tires from the "name" makers COULD be rated at 160 PSI if the manufacturers wanted to reduce the margin of safety. And, for marketing reasons, one company in particular like to stamp very high PSI numbers on its tires. But, the MAXIMUM PSI and the BEST PSI are two very different concepts.

The tire must have a slight bit of sag under full load to allow the sidewalls to flex when going over bumps and to absorb road shock. A tire with "zero" sag will beat itself to death on rough roads, while providing a narrow contact patch, with an adverse effect on cornering and braking ability.

ajst2duk

Nicely put, & a good point too by Machka.
Often riders get into a "harder is better" mentality (tyre pressure) thinking that they are reducing rolling resistance, when the opposite can be true.
I started off with this way of thinking, but these days find that I run with just enough pressure to minimise the risk of pinch-flats as I do most of my riding on coarse stone chip seal. Comfort is much better, and seat-of-the-pants feel is that it is also better from a rolling resistance point of view as well. I weigh around 180-190lbs, depending on how many pies & beers I've had lately, so I'm no lightweight, running 90F & 100-110R.
If my riding was done on smooth seal, I would be running them around 15psi higher, so there are many things to consider when looking at tyre pressures.

clausen

100 in the front 110 on the back on Vittoria Rubinos I'm 170 lbs.
To those running high-pressure check the owner’s manual of your rims, they may not be recommended for those high pressures.

oboeguy

I have the Vredesteins too but keep it at around 110psi lately for comfort (and I weigh about the same as you, 190lbs).

bikebugmenot

100psi front/105psi rear

Chris631

115 front/125 rear... but maybe 60 now as she's sitting sadly idle

+edit...25mm, 164 lbs

Looneytuna

110 front / 120 rear running on Veloflex Pave.. weight 200... ran 5 psi higher in the summer when I first started using them.

BigFloppyLlama

120 front and rear on michelin carbons.

fmw

None of the above. I run 105 psi in the rear and 90 in the front.

SilentShifter

My tires want 100 front and rear, so I use 100 front and rear

NoRacer

I tried some higher pressure (150 psi max) kevlar belted tires that were said to be of lower rolling resistance, but they never performed as well as the Michelin Pro 2 Race tires that originally came with the bike (116 psi max). I replaced the kevlars with Michelins after about 2 weeks of solid use.

alanbikehouston

Again, IGNORE the PSI marked on the tires. That is only a safety rating that estimates the MAXIMUM safe PSI for an average weight rider using "average" rims (and then builds in a generous extra safety margin).

Even if a tire is marked 150 PSI, 160 PSI, or 180 PSI, the PSI level that provides some sidewall flex and a wide contact patch (both of which are necessary for optimum performance) is likely to be far, far lower.

My point? The tires marked 150 PSI that you did NOT like might have performed very well for you at 90 PSI or 100 PSI, depending on their width and your weight.

Who needs to be riding at 160 PSI? Well, if you are riding for a time trial record on a smooth wooden track, using skinny tires at high pressure might give you a couple of extra seconds over an hour of riding. But, if you are going to be riding for two or three hours over the broken bits of concrete that the USA likes to call "roads", you will get a more comfortable and stable ride at a much lower PSI.

An easy way to tell if your PSI is correct: when you sit down on the bike, the sidewall profile of the tires should bulge very slightly and the rim "sag" a tiny bit...about 1/8th inch toward the pavement. A buddy standing directly next to the rear wheel ought to be able to see the rim move slightly when you get on the bike. Zero sag? Then you might as well be riding on a wooden wheel...that tire is not going to absorb any road shock.

YMCA

7 bar max (100psi)
Why anymore?
Better comfort, traction and the tires wear evenly.
Rainy crits, I'll go to 90psi.

NoRacer

I've read Sheldon Brown's article about all of this, but thanks for reiterating.

I average 150 pounds. I take note of when the tire bounces on bumps instead of deforming and remaining in contact with the road.

R900

Hutchinson 23's, and I'm about 195 so I run 110 psi front, and about 125 psi rear.

John

bbattle

Same here.

StanSeven

So true. I also did that thinking I would be faster. It wasn't until I read many similar posts over time that it finally sunk in that rolling resistence can be greater with added pressure. It took reading a couple people's explanation before I got it.