Can tire blowout cause a bad wheel alignment?

Had a rear wheel blowout and now the wheel is out of alignment. Do not feel any loose spokes. Is
this possible to happen? Or could what have caused the blowout also caused out of alignment? Did not
hit any big holes before the incident. Did have several big thump, thump, thump sensations right
before the blowout.From one previous experience long ago I knew what was coming when I felt the
thumps. Oh sh-t!!

Jim

 

> Had a rear wheel blowout and now the wheel is out of alignment. Do not
feel
> any loose spokes. Is this possible to happen? Or could what have caused
the
> blowout also caused out of alignment? Did not hit any big holes before the incident. Did have
> several big thump, thump, thump sensations right before
the
> blowout.From one previous experience long ago I knew what was coming when
I
> felt the thumps.

The thumps you felt were probably from the tire leaving the rim and contacting the brake pads, just
prior to the blowout. This is generally an indication of an incorrectly-installed tube, where the
tube is pinched in between the rim and the outside of the tire. Over time the air pressure levers
the tire up and off the rim, and blam-o!

Because a blowout results in suddenly riding on the rim instead of the tire, it's possible to do
some damage (knock it out of alignment a bit). Is it dented or more of an "s" curve?

--Mike-- Chain Reaction Bicycles http://www.ChainReactionBicycles.com

 

>--Mike-- Chain Reaction Bicycles-answered

>Because a blowout results in suddenly riding on the rim instead of the tire, it's possible to do
>some damage (knock it out of alignment a bit). Is it dented or more of an "s" curve?

No damage to the rim. Forgot to mention the blowout occurred at the valve area. If you were
referring to the alignment of the rim in your question, it had more of an "s" curve when spinning
it. The wheel "god" seems to have it in for me now as the rear wheel from my favorite bike is in the
shop being rebuilt at this time.

Jim

 

> Not necessarily. True blow-outs (casing rupture) can also be preceded by noticeable 'thumps', as
> the casing threads tear and tire shape starts to distort.

But later evidence shows that, in all likelihood, this particular blowout was caused by a
poorly-installed tube. The giveaway is that it happened in the valve area, where the tube is thicker
and it's fairly easy to get it messed up there, unless you physically check to make sure the tube is
"floating" inside the tire by pushing up on the valve.

--Mike-- Chain Reaction Bicycles http://www.ChainReactionBicycles.com

 

> This is the wheel god's way of telling you to learn wheel building.

There's a substantial difference in skill and time needed to learn how to build a wheel, vs true
one. I wouldn't want to discourage somebody from learning how to simply true a wheel by suggesting
that what they really need to do is learn how to build one.

--Mike-- Chain Reaction Bicycles http://www.ChainReactionBicycles.com

 

[email protected] (Jpfler) wrote:

> Had a rear wheel blowout and now the wheel is out of alignment. Do not feel any loose spokes. Is
> this possible to happen? Or could what have caused the blowout also caused out of alignment?

I don't know if we're talking about the same thing, but...

There have been a few times I have had a tire blow off the rim forcefully enough to knock the wheel
out of true. I would have a hard time believing it had I not observed it more than once.

These were instances of high pressure (100-150psi) being pumped into good sized tires (28-50mm) and
blowing out explosively-- with a sound like a gunshot-- either while being pumped up or shortly
thereafter while just sitting. The times this has happened to me, I knew for certain that the wheels
were running true before the tire blew off, and I could observe immediately that the wheels had been
knocked crooked.

It hasn't happened in a long while, so I can't really remember well enough to say whether any or all
of the affected wheels were well-built.

Chalo Colina

 

Mike Jacoubowsky wrote:
>>Not necessarily. True blow-outs (casing rupture) can also be preceded by noticeable 'thumps', as
>>the casing threads tear and tire shape starts to distort.
>
>
> But later evidence shows that, in all likelihood, this particular blowout was caused by a
> poorly-installed tube. The giveaway is that it happened in the valve area, where the tube is
> thicker and it's fairly easy to get it messed up there, unless you physically check to make sure
> the tube is "floating" inside the tire by pushing up on the valve.

Why do you believe that all tire blowouts are due to a poor tube installation? In these cases, your
guess about the later evidence is incorrect, the casing blowouts did not occur at the valve. As I
had said, in some cases before the blowout the tire was seen to be deformed, even though the bead
was perfectly seated all the way around. After each blowout, it was seen that there was a tear
completely through all the casing plies, frequently originating underneath the tread. The hole in
the inner tube corresponded to the location and shape of the tear through the casing. How can a
misaligned tube cause the casing to give out and tear under the tread?

You shouldn't confuse a a blowout (casing rupture) with a blowoff (unseating of the tire
form the rim).

Mark McMaster [email protected]

 

> You shouldn't confuse a a blowout (casing rupture) with a blowoff (unseating of the tire form
> the rim).

I don't recall the original poster ever saying the tire was damaged.

> Why do you believe that all tire blowouts are due to a poor tube installation? In these cases,
> your guess about the later evidence is incorrect, the casing blowouts did not occur at the valve.

I never said *all* blowouts were caused by poor tube installation. I said-

"This is generally an indication of an incorrectly-installed tube, where the tube is pinched in
between the rim and the outside of the tire. Over time the air pressure levers the tire up and off
the rim, and blam-o!"

I don't recall any "later evidence" being introduced; perhaps my newsreader didn't pick it up?
Blowouts can certainly be caused by a tire failure, but in my experience, which is pretty
significant given the number of bikes I deal with, most are caused by improperly-installed tubes.
Second place would probably go to tires damaged by road debris, third place to sidewalls worn
through from improperly adjusted brakes, and somewhere way down the line would be a defective
tire casing.

--Mike-- Chain Reaction Bicycles http://www.ChainReactionBicycles.com

"Mark McMaster" <[email protected]> wrote in message news:[email protected]...
> Mike Jacoubowsky wrote:
> >>Not necessarily. True blow-outs (casing rupture) can also be preceded by noticeable 'thumps', as
> >>the casing threads tear and tire shape starts to distort.
> >
> >
> > But later evidence shows that, in all likelihood, this particular
blowout
> > was caused by a poorly-installed tube. The giveaway is that it happened
in
> > the valve area, where the tube is thicker and it's fairly easy to get it messed up there, unless
> > you physically check to make sure the tube is "floating" inside the tire by pushing up on the
> > valve.
>
> Why do you believe that all tire blowouts are due to a poor tube installation? In these cases,
> your guess about the later evidence is incorrect, the casing blowouts did not occur at the valve.
> As I had said, in some cases before the blowout the tire was seen to be deformed, even though the
> bead was perfectly seated all the way around. After each blowout, it was seen that there was a
> tear completely through all the casing plies, frequently originating underneath the tread. The
> hole in the inner tube corresponded to the location and shape of the tear through the casing. How
> can a misaligned tube cause the casing to give out and tear under the tread?
>
> You shouldn't confuse a a blowout (casing rupture) with a blowoff (unseating of the tire form
> the rim).
>
> Mark McMaster [email protected]