Volunteering for a fondo ride, I helped w/ a puncture, & offered to take the tube so

the rider wouldn't have to deal with it.

I tried to locate the hole, out of curiosity, but the air escaped too fast.

Later, at home, found & patched the snake bite pair of holes, but on testing, found another, small puncture.


My theory is that the small puncture came first, & the pinch flat happened after the tire had lost some pressure.

I wonder if this is not the case for some of those mystery 2nd flats- the obvious pinch flat is blamed, missing

an embedded thorn that started the process.

This possibility is why a pro wrench always checks the tire casing for offending objects, regardless of the initially thought reason of the flat. This takes only a few minutes and can save much more later on down the road. That riders neglect this step when on the side of the road is their problem, maybe.


I have been part of the initial forensic anaylsis of a few law suits involving "accidents" (a word often used when "incidents" would be the better description). It is interesting how people will try to bend one's observations/conclutions when they don't agree with their claims are not found to hold water. Two times the tire going flat just before the incident (the impact with the other vehicle) contributed to the situation. Both times other's anylsis were saught. Both times my initial views were confirmed. Andy.

My rule is if I get a flat and can't find what caused it, I'm going to get another flat. I keep checking the tire, the tube, the rim, rim strap, spokes...everything. 9 times out of 10 I find the cause. That 1 time out of ten I don't, and if I slap another tube on the wheel, I invariably get another flat on that tire in short order.

I've been known to use a corner of my bike jersey to check the inside of a tire for burrs, glass bits, steel-belted radial tire wire, etc. Works like a champ if one can't find an obvious cause for the flat.

^^^ Ditto. My favorite is the cut in the tire that's not big enough to let the tube blow, but lets it out enough to be abraded by the tire casing. You get a flat, fix it, inspect the inside of the tire and find nothing, put the bike back together and continue riding. 20 miles down the road, you get another flat in the same spot as the first. Really frustrating.

I've had this happen 3 times in 40 years of riding. Grrr...

Maybe damage from using levers to install the tire. I always try my best not to use them to install.

Always hard to guess when you can't match the tube up to the tire/wheel after removing it. But the last five or six flats I got, and I very much hate to admit it, where my fault.

Most of them because I was trying to make some thirty year old velox last a little longer. Something I cleaned the wheel with softened the adhesive in one area and let it slide exposing the spokes. New tape, no more of those problems.

The other two were damaging the tube while getting in a hurry and letting it get pinched between the wheel and the tire bead while installing the tire. Both held air long enough to let me get to the far end of the trail before calling my wife to bring the SAG wagon.

It has been a while since I've had a puncture flat from something going through the tire.

I suspect this is the case more often than people realize. But whenever someone mentions a pinch flat here on BF, they get an earful about not pumping up their tires often enough.

tire label lined up with the stem will help you find the puncture inducing item, remaining in the tire,

so putting a fresh tube wont be flattened ,promptly,by the same thing , again..

The rider ran his fingers around the inside of the tire for a basic check

& did the rest of it well, so hopefully had no further trouble.

He was from out of state on a rented bike & didn't know what he would find in the saddlebag.

Yep,

I've had slow leaks that resulted in pinch flats... then second slow leaks that were a pain to track down.

Those invisible radial wires

I periodically inspect the tires for glass and thorns from the outside, and try to keep up on getting the glass out.

Radial ply tire wire is my biggest problem with flats. Sometimes very hard to find.

Yes, that's a possibility, along with the possibility that the puncturing object woodpeckers and causes multiple holes, including extreme cases where you get holes both on the tread side and belly.

This is one more reason for replacing tubes in the field and doing repairs at home. BITD the shop I worked in sold used tubes. We'd allow a small amount for customer used tubes, and toss them in a box. When there as dead time, we'd fix large batches, then inflate and hang them to "age" for 48 hours. Those that were still inflated, were deflated and put in the ready to sell box. The flat or soft ones were chucked.

BTW - this wasn't about money, since out cost on new tubes was something like $0.60, but instead was a token effort at cutting down on unnecessary solid waste.

I've wondered about that. Some online vendors sell tubes at about $1 to $3 each depending on the tube.

Yet, some local bike shops sell them for $8 each.

So, say $0.80 to $8.00 is 10x, or a 1000% markup... not bad

I don't like to inflate my tube immediately after patching if not going into a tire. But, I sometimes skip that step of checking my work, which could potentially lead to dire consequences.

You missed the part about it being while I was in retail, which ended in 1973. Tubes have gone up considerably since then, with prices tracking with the price of oil. So, $0.50 wholesale tubes went away with 27-9/10ths gasoline.

However, I agree that $8.00 is pretty steep. Here in the NYC area, $5.00 is more typical, with a few shops offering them at $5.00ea, or 3 for $10.00 hoping to retain some of the business that otherwise would go to the net.

A couple of pounds of pressure left overnight will show if it holds air & barely stretch the rubber.

I've just been rolling them up and organizing them once satisfied that the patch would hold air in the moment. That 48-hour trial period is golden; I'm gonna start doing that.

I had heard about this technique, and finally started regularly doing it years ago, and it has helped a few times with those hard to feel hidden objects that might get overlooked with a quick, not really lookiing closely finger run around inside the tire.
Knowing where the puncture occurred on the tire allows you to do a real close inspection, flexing the tire inwards or outwards to sometimes expose a little thing that otherwise stays hidden and embedded in the tire.

(and I would add, a real benefit to those of us with older eyes!)

good to bring this up, as it really can save time and hassle, and is easy to get into the habit of doing, doesnt cost a cent and only takes seconds to do.

This is a good practice, and also shows attention to detail, like assembling a wheel so the hub maker's mark is facing the valve hole. A few years ago I started installing tires with the inflation pressure information centered over the valve hole. With my porous memory, I usually forget what the pressure's supposed to be between top-ups, and this makes it easier to find the PSI rating.
Steve