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Tire Pressure Phobia

I am sorry, guys, but it’s now 2 for 2 when it comes to discussions concerning tires.



To review: Peterson called in because he had a phobia about putting air into his tires. As a kid, he had a friend who was injured by an exploding tire. After many years, the woman he was with had convinced him to give it a try - and nothing happened!



However, this was followed up with an ancedote at work where someone’s cousin had a tire explode while filling it.



Your advice was right on - the odds are extremely low that this would happen and he should forget about it.



HOWEVER, Tommy - in his effort to make a connection with Peterson - relayed his phobia about old style trucks with split rims.



First, it’s hard to find a split rim in use nowadays. Been that way for deacades - and as an anecdote, is un-necessarily alarmist - and Peterson was right in pointing that out.



You guys said that the primary reason this happen is from overinflation!



Sorry, but that is 100% wrong!



The primary reason this happens is because the tire was damaged - because the tire was operated UNDER-inflated - AND - the best precaution is to regularly fill your tires to the proper pressure.



and defective? Every tire is inflated before it leaves the factory - and if it was defective it would have exploded there!



I realize you guys don’t deal with tires much - and an occasional slip is to be expected - but seriously! I think you guys need to get some assistance before you answer another tire question.

Good post! It is not the worst phobia to deal with, I think to avoid the worry the place where Peterson bought the tires would check the air pressure for free anytime.

Agree-you’ve made several great points, CR. It’s taken me years to understand that tires blow out from underinflation-caused damage, not overinflation. And I last saw a split rim 30 years ago, when my boss at the gas station (stupidly) agreed to fix one, and, lacking the proper safety cage, used the lift to try and protect us as he refilled the repaired tire. Luckily, nothing happened.

When facing off with thy dreaded tire dragon, best thou have thine armor :wink:

I had split rims on my 1950 Chevrolet 1 ton pick-up truck. The tire company that I dealt with had a cage that they put the tire in when they inflated it.

I saw my friends overinflate bicycle tires and blow them out when I was a kid. I had a bicycle tire blow out when the bicycle was parked with nobody on it. In this case it was probably over-inflated.

Tires popping has to be one of the least possible ways to be injured. Falls and electrocution seem to be more likely causes. Eye protection will prevent 95% (my own statistic, fabricated) of the possible injury from a popping tire on a car. If a person doesn’t do foolishly unsafe things, he will be “safe”. We’re all afraid of something and tires are in his fear department. Nothing much we can do to change that.

Good post.

So…that 250 psi I put in my snowblower tires is okay?

yeah, I’ve ran 450 with no problem :stuck_out_tongue:

It must be the chains that keep it safe…

It never occurred to me to fret about my car’s tires with 30ish psi. On the other hand, I always pass tractor-trailer trucks expediently because of those huge tires that can have up to 120 psi. My wife once passed a semi when a tire blew out and she was blown/scared into the next lane (uneventfully). It’s probably kinder to the driver anyway to get past and out of the way.

Of course, it’s not just the pressure, but the size (potential difference multiplied by volume). A 30psi blowout of a car tire is more spectacular than a 110psi blowout of a bicycle tire. So, I still respect car tires, but I’ll never get the chance to see one so wimpy that it blows out at 30psi while cold and stationary.

My sister filled up a ten speed bike’s tires.Blew up a tire.This was at ucsb with sea salt,Iv parties,and never having the same bike from day to day.
Still will not fill her car tires by herself.Loved the armour pic.

I did that to a 10-speed tire once too.

The gas station compressors are capable of maintaining high pressures at high volumes (they need that to run the tools) and are too much too fast for the tiny amount of air in a bike tire. Car tires contain far more volume than bike tires, so the volume of air being pushed into the tire raises the pressure at a far far slower rate, slow enough to control the total pressure.

I was wondering about plumbing up a gauge/fill valve unit with a long hose attached to a clipon stem fitting. The hose could be long enough for Peterson to stand beside the car fender while he cycled the fill valve until the correct pressure was attained on the gauge and then he could unclip the stem fitting once he was done.

I have concerns when I am filling a compact spare to the 60 psi or so. A lot of time these tires have spent a lot of time idle in the trunk so they could well be over life on age alone. This is where I do not want to standing over the tire/wheel as I bring up the pressure. So I stand beside the tread and reach my arm only over to pressurize. So far no bangs or flying wheels.

At a store that sells air tools you can buy exactly that setup, or the parts to screw one together. I have one at home.

I don’t think of 60 psi as being that much. Bicycle tires go that high and higher.

CAUTION:

Comparing bicycle tires with car tires is like … ah … comparing bikes with cars. They are designed around completely different sets of circumstances - and inflation pressure is one of them.

A typical car tire is inflated around 32 psi, while bicycle tires are much higher. Both are designed with those inflation pressures in mind - and the result is quite different.

But in the case of temporary spares - they also were designed to take the 60 psi specified - and if someone is concerned about the age of the tire and it might blow apart … well it takes decades for this to happen. You’re more likely to have the tire fail in service, then in the trunk!.

This was an “encore presentation”. I sent an e-mail to the show at the time recommending that they call him back for “stump the chumps”, but I don’t think they did.

I also recommended that they tell him that checking the tires will not cause them to explode as he is not adding air. Also, there are electric pumps with a remote on off switch and built in gauge so he could add air from a safe distance away.

There are established treatment methods for phobias – chiefly desensitization, i.e. dipping your toe and then going in closer and closer to what you fear. You can find therapists who specialize in this. In Peterson’s case, “desensitization” might mean first testing the pressure several times, day after day, until that feels commonplace; then filling the tire with a floor pump, then later with a gas station hose at a specific station, then trying a variety of gas stations.

Also, as a scientist, I personally would welcome a prescription that is known to be safe. For example,
(1) test the pressure first to see how far you have to go; that ensures the pressure is not already over the rating.
(2) put the gas station hose on for a count of 3; that’s certainly only enough time to add a few psi, not enough to exceed the proper pressure by a large amount. (For bike tires, I’d only do about 1 sec at a time on a gas station hose, and only if I couldn’t find a floor pump.)
(3) check the pressure again, to see how far you still need to go. If it’s over the proper number, it won’t be dangerous, so you can just bleed it off until it’s at the proper pressure.
(4) keep edging upward until the tire pressure is correct.
I claim that this gives you enough control to keep the pressure at a safe value – less than about 40 psi, or maybe 20% over the proper number. Even if it fails then, because of damage or defects, there’s no way for the tire to store enough energy (volume times pressure) to cause personal injury in the explosion. It’ll spoil your day, but it can’t send you to the hospital. “Spoil” means you’ll need to take time to calm your nerves and look for your spare and then a tire shop. Like normal!