# why did my tire explode



## 9four (Aug 27, 2007)

I replaced my front tube yesterday - pumped it up to the PSI specified on the tire (75). I rode 8 miles to work this morning - about an hour after I got to work I hear an incredibly loud boom - like a gun shoot.

I walked over to my bike to find that my front tube had exploded - a 12" rip along a seem. Is there anything besides a defective tube that could have caused this?


----------



## talentous (Oct 17, 2005)

*sound like a*



9four said:


> I replaced my front tube yesterday - pumped it up to the PSI specified on the tire (75). I rode 8 miles to work this morning - about an hour after I got to work I hear an incredibly loud boom - like a gun shoot.
> 
> I walked over to my bike to find that my front tube had exploded - a 12" rip along a seem. Is there anything besides a defective tube that could have caused this?


pinch flat to me. Did you inflate the tub slightly before putting it on?


----------



## 9four (Aug 27, 2007)

When I installed the new tube - With tire partially on the rim I put the tube around the rim - slightly inflated - a little more than enough to give it shape. I inflated it a bit more once it was secure on the rim and then ran my fingers along the rim/tube to make sure there were was not any section that was bunched up - nice and even. Once I did that, I put the tire completely on and inflated to 75 PSI.

I didn't check to see if it was flat/low once I got to work but it seemed fine on the ride in.


----------



## Dave_Stohler (Jan 22, 2004)

Well, it sounds like you pinched the tube putting the tire on. Any bike mechanic can tell you that you need to *put the tube inside the tire first*, then mount it on the bike. From what you're telling me, you only took one side of the tire off and then yanked the tube out? That's the stupid way of doing it. You need to always remove the tube and the tire completely.


----------



## Bocephus Jones II (Oct 7, 2004)

9four said:


> When I installed the new tube - With tire partially on the rim I put the tube around the rim - slightly inflated - a little more than enough to give it shape. I inflated it a bit more once it was secure on the rim and then ran my fingers along the rim/tube to make sure there were was not any section that was bunched up - nice and even. Once I did that, I put the tire completely on and inflated to 75 PSI.
> 
> I didn't check to see if it was flat/low once I got to work but it seemed fine on the ride in.


What kind of tires are you running that require 75psi?


----------



## Bocephus Jones II (Oct 7, 2004)

Dave_Stohler said:


> From what you're telling me, you only took one side of the tire off and then yanked the tube out? That's the stupid way of doing it. You need to always remove the tube and the tire completely.


Why? I do it that way all the time...saves time reseating the tire on the rim. Of course you need to make sure that the new tube gets seated properly, but you'd have to do that regardless.


----------



## 9four (Aug 27, 2007)

Bocephus Jones II said:


> What kind of tires are you running that require 75psi?


The stock tire of a surly cross-check - Ritchey SpeedMax Cross


----------



## 9four (Aug 27, 2007)

So if I understand the consensus we seem to be reaching - I didn't seat the tube properly. Kinda weird that it would just blow after sitting still for an hour.

I really want to avoid doing this again - who knows what would have happened had I been riding when it happened. So, this is basically a failure on my part to get the tube fully INSIDE the tire?


----------



## Bocephus Jones II (Oct 7, 2004)

9four said:


> So if I understand the consensus we seem to be reaching - I didn't seat the tube properly. Kinda weird that it would just blow after sitting still for an hour.
> 
> I really want to avoid doing this again - who knows what would have happened had I been riding when it happened. So, this is basically a failure on my part to get the tube fully INSIDE the tire?


yup...that's likely it. When you first inflate a few pumps stop and squeeze the tire all around to make sure that it's inside the tire and not caught on the rim.


----------



## ethebull (May 30, 2007)

Scenario #2, you may have had the tube situated properly, but the bead of the tire wasn't properly seated. After inflating the tire to 30lbs or so, it's a good practice to check that the bead has seated evenly. Using your hands, work the tire like you're trying to roll it off the rim with the palms of your hands. Work the full circumference of the tire seating the right side, then repeat the process on the left. Spin the wheel and be sure there are no lumps or dips. Inflate fully and spin once more. Done. Takes an extra minute or two, but should avoid future blow outs.


----------



## 9four (Aug 27, 2007)

When I walked over to the bike the tire was already half off the rim. It seems like this would indicate scenario #2? Regardless of what actually caused it I have certainly learned a lot about properly installing a tube.

Thanks for everyone's replies, I really appreciate all the info.


----------



## barry1021 (Nov 27, 2005)

*+1*



Bocephus Jones II said:


> Why? I do it that way all the time...saves time reseating the tire on the rim. Of course you need to make sure that the new tube gets seated properly, but you'd have to do that regardless.


cannot see any reason to take the whole tire off unless you are replacing it..


----------



## RHankey (Sep 7, 2007)

Yep - most likely scenario #2, as the delayed blowout with tire blown off the rim is the usual outcome. Don't feel like it's a beginner mistake. Some tire/rim combinations can require a fair bit of persuasion to seat properly. In some instances, I've had to use dish soap and varying amounts of air pressure and thumping to help the bead slide into place.


----------



## John Nelson (Mar 10, 2006)

Did the tire feel bumpy on the ride? Wonder what that thump-thump-thump was?

I agree with the others that you likely pinched the tube between the tire and rim or didn't set the tire properly. I think even the more careful of us might make this mistake once in every long while.

But you should now carefully inspect the tire itself for any sidewall damage, which could have been either the cause or the effect of the blowout.


----------



## rogerstg (Aug 1, 2007)

Dave_Stohler said:


> Any bike mechanic can tell you that you need to *put the tube inside the tire first*, then mount it on the bike. From what you're telling me, you only took one side of the tire off and then yanked the tube out? That's the stupid way of doing it. You need to always remove the tube and the tire completely.


That's the dumbest thing I've heard.ut: I've never taken the tire entirely off the rim to change a tube, neither does Leonard Zinn, Sheldon Brown or any rider or mechanic that I know.


----------



## x3u93n3x (Apr 1, 2007)

i've had that happen twice now. i don't know the exact reason, because i do know how to put a tube in properly.

frankly, i kind of enjoy that sound and the panicky feeling i get when it happens while i'm riding. just carry an extra tube! ;-)


----------



## brianmcg (Oct 12, 2002)

I had this happen recently when I changed the tubes on my 35mm Paselas. After inflating them both. Both tires went off about 30 minutes later. The Paselas are quite picky at how they get put on a rim. They just were not "clinching" the rim correctly.


----------



## ethebull (May 30, 2007)

brianmcg said:


> I had this happen recently when I changed the tubes on my 35mm Paselas. After inflating them both. Both tires went off about 30 minutes later. The Paselas are quite picky at how they get put on a rim. They just were not "clinching" the rim correctly.


Yes, the 35mm Pasela is picky about seating the bead. Generally true of all wider tires.


----------



## Dave_Stohler (Jan 22, 2004)

barry1021 said:


> cannot see any reason to take the whole tire off unless you are replacing it..


Unless you take the tire off completely, there is no way you can fully inspect the inside of the tire for glass/etc. You also can't look for internal rim problems, such as a spoke sticking through the rim tape, or (this happened to me recently), a poorly ground weld scar on the inside of the rim. Considering that you already have the wheel off, the few extra seconds it takes to fully remove the tire is good insurance against missing something. Back when I first worked as a bike mechanic 30 years ago, the shop owner said that was the only proper way to fix a tire. "If you don't, and they get 2 miles down the road and have a second flat, you're gonna fix it after work, on your own damn time", he said.


----------



## John Nelson (Mar 10, 2006)

Although I agree that removing the tire completely allows a much better inspection, I don't know what that has to do with the problem being discussed in this thread.


----------



## Fredrico (Jun 15, 2002)

John Nelson said:


> Although I agree that removing the tire completely allows a much better inspection, I don't know what that has to do with the problem being discussed in this thread.


Inflating the tube just enough to give it a donut shape, then putting it inside the tire, then putting the tire on the rim, is the most foolproof way of avoiding pinching the tube between the tire bead and the rim. It's also the best way to avoid having the tire bead seat unevenly when pressured up. Of course spinning the wheel in your hands will show whether the bead is seated evenly or not.

Also, talcum powder is the best lubricant between tube and tire. It allows the rubber to slide into place without stretching or ripping when aired up. One guy mentioned on this site that talcum also allows the tube to slide (instead of stretching) inside the tire when riding, thereby reducing rolling resistance. How about that for an imponderable?


----------



## Dave_Stohler (Jan 22, 2004)

John Nelson said:


> Although I agree that removing the tire completely allows a much better inspection, I don't know what that has to do with the problem being discussed in this thread.


Well, because what the newbie did was this: He crammed the tube in poorly, then probably caught it on the bead when it inflated, because the tube wasn't properly inserted fully inside the tire and out of the way of the bead. A tube put inside a removed tire then inflated to about 1psi won't get under the bead.


----------



## PltJett (Nov 23, 2006)

I've had this happen at the track before to me. Only it was because I was a smart cookie and left it in the 110° sun for 2 hours.


----------



## mohair_chair (Oct 3, 2002)

Scenario #3: You have a large tear or gash in the sidewall of your tire. If you get a big enough gash in your tire, the tube will bulge out like a hernia, and eventually it will explode with a loud pop, shredding the tube in the process. It's not really obvious what is happening, so most people will put in another tube, pump it up, and within a few minutes, it will mysteriously explode again. If this happens, check the tire sidewalls very carefully before wasting another tube.

The only chance you have to make a tire like this ridable again is to use a tire boot (look it up) to patch the gash in the tire. A dollar bill or part of a Fed Ex shipping envelope might also work. Whatever you use might not hold for very long, so if you are at mile 20 of a 100 mile ride, you might want to consider turning back. The tire is gone, and you need to replace it ASAP.

http://www.rei.com/product/738836


----------

