ablang

So I keep my bikes in the garage. I went into the garage one day to pump up my tires. We had a string of 100+ degree days in a row. I found that my front tire (which can inflate up to 100psi 27x1.25) apparently blew up.
My tires can lose up to 40% psi overnight, so I'm surprised my tire could still blow up.

They are puncture proof and lasted about 11 years. I paid $50 for the set of rubber tires.

Kabuki12

I had it happen once on a ride. I used to keep my tires inflated to max pressure, and then on a hot sunny day I stopped at a bench to eat an apple and BANG!! The bench and bike were in direct sun.Darn near scared me to death and I ended up walking to my shop (about 2 miles) as the side of the tire was completely blown out!

fietsbob

Have pre hook bead rims? they were a thing in the 27" wheel/ tire era ..

Had them blow off the rim in the shop with air- compressor .. had a casing sidewall split (inner-tube aneurysm out the tear)

Deflated the heavy duty tube before it burst..

VegasTriker

Blame it on you being cheap or thrifty (your choice). 11 years on a set of tires is really pushing it. I wear out my tires way before even a couple of years. Even if you don't wear out the tread, the rubber deteriorates with age and the tire cord gets weaker.

We have had just a couple of days in the past two months when it didn't get over a hundred and many when it is over 110F. I haven't had any tires explode inside my garage where it is sometimes at least as hot as outside. That includes 700C X 23 tires pumped up to 100 psi.

ablang

Considering I bought the bike for about $100 (used) in 2009, I don't think $50 for puncture-proof tires is considered "cheap". I probably put about 2009 miles on them tires the first year and have gotten a lot less on them over the years since my 1st kid was born in 2010. I'm not surprised the other tire lasted this long. It still seems to have good tread left on them.

BoraxKid

I've never had a tire just randomly blow up in the way that you described. I did have a tire blow out at multiple points while riding in very cold conditions on a very old tire. My wife and I were riding a few years ago on a Saturday in February in the Midwestern-Eastern USA DMZ. The temperature was just below 10F (-12.2C), and her back tire was probably about 2-3 years old. Right as we got to the farthest point out on our planned ride, her back tire just exploded. There were 4-5 distinct parts of the tread area with strips of rubber hanging off that were near big rips in the tire. I chalked it up to old tire + extreme temperatures = catastrophic failure.

Lucky for us, we were near a bus route that would take us back into the city. We had to wait about 30 minutes in the cold, but the adrenaline rush from the blowout happening in suburban traffic kept us warm for a bit.

Milton Keynes

Only time I ever had a tire blow like that was when I was driving home after a ride on a rail trail. I had the bike in the back of the truck, and I heard a pop at some point during the drive. When I got home, I found that the tube had blown, destroying the bead of the tire. I think the tire was old and had a little bit of dry rot.

Recently, though, I had a strange thing happen. I had taken my mountain bike to the shop to do some routine cleaning & maintenance, which also included airing up the tires to proper pressure. When I got home, I still had the bike in the back of the truck when I heard a loud "PSSSSHHHHH!" The rear tube had blown. I waited to fix it, and a day later the front tube had blown. They both blew out at the valve stem. The rear one wasn't very noticeable, though, and only putting it in water could you see that it was leaking from around the rubber where the metal part of the Schrader stem attached. The front one, though, was far more dramatic and the valve stem was sticking out at an angle. The strange thing is that they both did that at the same time. I could understand one of them blowing out the valve stem, OK maybe it got old or something. But I think the tubes were of different ages and different manufacturers, so it was strange they'd both go at the same time.

ThermionicScott 

Steel rims?

ablang

I don't know. Maybe. It's definitely a heavy "road" bike.

Trakhak

Quoting in case you missed this crucial question. The 27" rims used with inexpensive bikes like the Schwinn World Sport, especially those manufactured before the early 1980s, usually had straight sides. Rims with a "hooked" design at the top hold the tire bead in place much better. Some tires specify different maximum pressures according to whether a rim is hooked or straight-sided. I'd avoid inflating any 27" tire over 70 psi or so on any straight-sided rim, regardless of the maximum pressure specified on the tire sidewall.

By the way, the tires on the bike are 27 x 1 1/4, not 27 x 1.25. Tires with decimal sizing and tires with fractional sizing are almost never interchangeable, for arcane historical reasons.

BoraxKid

This doesn't sound strange at all. It sounds like whoever aired up the tires was very careless about how they pulled the pump head off of the valve stems and that, in turn, caused holes to be ripped in the tubes where they meet the valves. It's easily preventable by grabbing the valve stem and holding it still while removing the pump head.

Milton Keynes

Well, I was the one who aired the tires up, and I didn't use a locking pump head. I used a standard Schrader valve stem inflator, and at no time was it locked onto the valve stem, nor could it be. So that's not the cause of those failures.

delbiker1 

I have had only one tire blow out. I was riding the bike at the time, It was the front tire and I was riding at a pretty good clip, 19 mph or so.I was very fortunate to not crash and get safely stopped in the emergency lane. This happened on a 2 lane bridge. This was back in the early 80's. I was riding a set of new Michelin 19mm tires. I hit an expansion joint and the tire blew. That was the last time I purchased or used such skinny tires.

BoraxKid

Whether or not the pump head was "locked" is not the issue. When you pulled the pump head off of your valves, you ripped a hole in the tube. It's called "operator error" and it happens sometimes. Calm down.

Koyote

I think this is the more likely explanation for the OP's problem. I don't recall the physics precisely, but (I think) the Combined Gas Law would apply. And I think the change in air volume for a temp change from, say, 80 degrees to 100 degrees, would be rather slight. (I'm betting cyccommute knows the physics right off the top of his head.)

ablang

Thanks for educating me. Yes, I think the tires are actually 27 x 1 1/4. I didn't realize there was a difference.

The tire sidewalls did specify a max pressure of 100 psi. I don't know if my rims did have a "hooked" design but I've always inflated to past 70 psi and didn't have a problem until a few days ago.

There certainly is a difference in effort bicycling at 100 psi vs 70 psi. I'm pretty sure I'd work harder biking w/ 70 psi tires.

Olefeller77 

I had an old Raleigh That I had bought new with lifetime guaranty. I rode that thing literally into the ground. I was on a RAGBRAI across Iowa . At an overnight stop I was riding across a park and crossed a shallow dip. The frame snapped at the bottom bracket. I called the wife back in Illinois and had her bring a frame and wheel set I had in the garage. I spent the next day building a bike . I bought a set of light racing type tires for it. Only lost one day getting it up and going . The next day I was on a long downhill trying it out for speed. The rider next to me was counting off the speed as I had no puter yet. Just as he said " 40 " my front tire went with a loud pop. It was good that we were on a stretch of RAGBRAI dedicated highway because I covered both sides of the road with all the grace and poise of a terror stricken 5 yr old . The tire was beyond saving. I got lucky and found a repair van at the top of the next hill. He looked at the tire and said he didn't have anything that fancy. lol I told him if he had tires that were tough as practical ,I needed both changed out.
Blown front tire at speed is something I never want to experience again.EVER
EDIT ti add- Raleigh gave me a brand new complete bike- NO COST

epnnf

11 YEARS? I never use more than 2 years, even if they still look good.

Several years ago, I was on a ride w/Dayton Cycling Club; front tire blew on a very seldom used road. DCC gave me a new tire! Still don't know how/why tire blew.

stevel610 

Had this happen to me about 3 weeks ago. 2 month old 700x40c Marathon Supremes, 4 year old 700x50-60c tubes, 9 year old plastic rim strips.

I was commuting and pumped them to their max 80 psi. Just finished a long downhill and was heading up a long incline. Front tube exploded blowing the tire off the rim. I was going about 4 mph.

Left the bike in a garage at work. Next morning maintenance guy comes in smiling. Rear tire had done the same thing. Scared the bejesus out of him.

Took it to the local REI on the way home. Determined it was likely the old plastic rim strip. Replaced both with Velox and properly sized tubes. No problems since.

Milton Keynes

And you're making assumptions that you don't know anything about. Again, I was not using a pump with a locking head. I used an air hose with a standard Schrader air chuck that couldn't possibly pull on the valve stems. It has absolutely no ability to pull on anything. And yes, I inflated the tires to the proper pressure.

Trakhak

Tires can blow off even hooked rims---tube pinched between tire bead and rim, tire installed such that the bead is low at one point and high at another, tire inflated using a gas station hose putting out a high volume of air in a fraction of a second, broken tire bead, etc.---but inflating a tire to a high pressure on a straight-sided rim is a crap shoot. (I used a cheap old 10-speed with straight-sided rims for commuting for a few months---never inflated the tires past 75 lb---and still one of the tires eventually blew off the rim.)

If, as seems very likely, you do have straight-sided rims, one consolation might be that there's been a recent trend among non-racer cyclists to use wider tires at lower pressure. According to rolling resistance tests, wider and softer tires give up very little in efficiency, especially on pavement that isn't perfectly smooth. Many people on this forum are enthusiastic about riding tires 38 mm (roughly 1 1/2 inches) wide or wider at 60 or 70 psi.

Koyote

60 or 70 psi? That's nuts. I run my 35s at around 40 psi, and could probably go lower. Gives a nice plush ride, and gives up nothing in rolling resistance.

wilson_smyth

when talking about a 100 dollar bike, I wouldnt base my tire decision on a percentage cost of the bike.
That said, 50 quid isnt cheap but not expensive, they were probably decent tires.

The bigger issue here is age. Rubber does not age well. Even if they had zero miles, 11 years is a long time and they will have deteriorated. If they were in direct sunlight much (even through a window) that wont help, and temperature variation doesnt help either. Over a few years (2-3) sunlight and temp variation probably wont weaken the tire enough for it to fail, but after 11 all bets are off.

BoraxKid

Again, since you didn't get it the first time, IT DOESN'T MATTER IF THE DEVICE LOCKS ONTO THE TUBE OR NOT. Whatever device you used to inflate your tires, you had to seat it properly on the valve head to get a reliable connection to allow air into the tube. When you pulled that device off of the valve, you did so carelessly, and that is what ripped a hole in BOTH tubes at the base of the valve stem. Stop being so sensitive about this; it's a common mistake that plenty of people make. It's double frustrating when it happens with a new tube, but it happens sometimes. Maybe just try to learn from your mistake and be more careful next time.

Milton Keynes

Well if you were there watching me making a mistake, then why didn't you say something?