VegasTriker

Look at the writing on the side of the tire. It should tell you the maximum tire pressure right along with information as to the tire size. Sometimes it will have a range.
Here is an example for the Kenda 700C X23 tire I use on the rear of my recumbent trike.

I never bother to actually measure the pressure, just pump them up hard so I can't depress the tire much with my thumb. If I let it get soft I will get the type of pinch flat your picture shows,

cxwrench

90psi in 32mm tires!?! That's way over inflated. 60-70 would be the max unless you weigh a ton.

Darth Lefty 

Pumped up rock hard is fine for 23’s. 90 should be excessive for 32’s, the whole point of bigger tires is to run them softer. But if you’re not really checking pressure or you ride through potholes …

kahn

I've read some suggestions to drag a cotton ball around the inside where the cotton fibers gets caught on the sharp object whether a shard of glass, a thorn or piece of metal. Probably would save some blood!!

79pmooney

+1

Notice those slits are centered on the side of your tube. They were caused by your rim bottoming out on a pothole, railroad tracks ... By definition, those slits were "on center". What you are seeing is a tube that was put in twisted; in fact 90 degrees in 3 inches. Bad. Twisted tubes cause problems - flats not associated with anything else. I'm not going to grade you or whoever installed that tube. But I also don't want to see you at the roadside with another flat.

Both the tiny tire wires and small pieces of glass can remain in the tread/cord of the tire and have nothing visible on either side if the tire. The way to find them is to patch your inner tube. Then put it back in and look very hard where the patch is (and exactly that far away on the other side of the valve stem - count spokes). It is radically easier to find something you know is in a 1 inch circle that something that might be anywhere along a 7 foot by 3 inch strip. And if you don't find it, your next patch will be over the last or exactly the same distance from the valve.

geepondy

Update: With help of my bike guru friend, we found a staple in the tire, not real obvious and only could tell from the inside. The staple must have caused a slow leak (I thought the ride was getting softer before the flat) then at a certain deflation point, the pinch flat occurred. Disappointed a staple would penetrate this tire I purchased ($50 plus each) for it's stated puncture resistant ability but my friend believes the staple probably would have penetrated most any road tire.

Troul 

Low TPI tire?

kahn

Just about a month ago, pedaling along and, oh, damn, squishy. Unlike the prior flat where finding a tiny glass shard was near impossible, this was easy. As I walked to the sidewalk, yup, a staple but easily spotted. I asked my friend, "how does a staple and two legs turn legs up and penetrate a tire?" Sure enough the tube looked like it had between bitten by a rattlesnake - two small punctures. New tube but wrestled with the tire for at least ten minutes trying to get the last three inches over and onto the rim. Then pumping up a road tire to 80+ pounds with a mini pump. Exhausted and the ride was only a quarter done!

trailangel

OP had an OE... Operator Error

Darth Lefty 

No fault, normal incident

geepondy

I'm learning as I go along. After installing new tube, I put 75 lbs in the tire (according to pump gauge) and I think you lose a little when you remove the pump. Tire still felt pretty hard to the touch but a noticeable smoother ride. Tire says max pressure 102 lbs. Maybe I'll go down to 70 next time.

Iride01 

I wasn't going to come back here, but the title has been bugging me everytime I see it.

And I'm not certain anyone directly addressed the title, but if so, good for you!

Clincher tires can be tubeless or with tubes. Matters not if the bead is hooked or smooth. It's still a clincher tire.

The other tire choice is tubular.

cxwrench

Nope, the air you hear is from the hose not the tube. As soon as you stop pumping the valve closes.

CliffordK

That is a common occurrence. Slow leak, then BAM, pinch flat, and the air is gone. Then you find the big hole and miss the small one.

If my tire is going flat, I can usually feel a couple of jarring bumps and I pull over immediately when I feel them, then decide if I want to try to baby it home, or fix on the side of the road.

When a radial tire starts going bald (often out of alignment, so one side wear), they start shedding tiny wires about the size of a hair. These wires can be almost invisible, but can cause repeated flats if you don't hunt them down and fix.

Sy Reene

Not exactly, but that's the right idea. The sound of escaping air is from the hose mostly. As soon as you remove the the pump head, the valve closes.

cxwrench

No...as SOON as you stop pushing down on the pump handle the valve closes. You go from more air in the pump chamber to more air (pressure) in the tube/tire instantly. NO air pressure is lost when you remove the pump head from a Presta valve.

Sy Reene

I believe that once the the pressure is equalized between the pump and tire, there's nothing keeping the valve either open or closed. Therefore, if you don't have a very good seal between your pump head and the tube valve, you'll watch the pressure slowly decrease as air leaks out.

cxwrench

No, still wrong. Here's how it works...
You put the pump head on an open Presta valve. If the tube/tire has air in it, say 30psi for the hell of it, it stays closed. You start pumping and the pressure in the pump becomes higher than the pressure in the tube so the valve opens and increases the pressure in the tube. When you reach the bottom of the stroke you're no longer pushing pressurized air anywhere so the pressure in the tube is higher than that in the pump hose and the valve closes. There is still some pressure in the hose but not enough to overcome the pressure in the tube so the valve stays closed. When you pull the pump head off the valve (the important word here is 'pull') the valve stays closed. The air you hear escaping is coming from the hose. The higher the pressure you pump the tire/tube up to the bigger the 'whoosh' of air coming out of the hose. It's really very simple. With many pumps you can hear the valve click closed when you reach the bottom of the stroke...my old Silca does this.

Sy Reene

Well.. we're way OT and hesitate to keep discussing. And perhaps we're talking about different pump styles. But, your first part is not how my pump works. I attach my pump head, and my pump's gauge immediate reads the pressure, before I've even started pumping. Likewise, pretend my tube has a slow leak -- if I pump it up to 80psi, I can stop pumping and then watch my gauge slowly move downward as air leaves the tube. Also my pump head has an air release button, so that if I've overinflated, I can push the button and let air escape to intentionally bring the pressure down. None of these things would be possible if my tube valve was closed if I am not pumping.

OTOH, no argument that when taking the pump head off the valve, the big hiss is coming from the air in the hose, since the valve closes so fast on the tube there's virtually no air lost there.

greysquirrel

Unless you're using sealant. The sealant can collect on the tube side of the presta valve preventing it from totally closing when you remove the pump head resulting in a slow air leak. When I close the nut on the presta valve the air leak stops. If it bothers me enough I have to remove the valve and clean it.