Patching a sidewall blow out
 

This morning my nice new thorn resistant tube blew out through the
sidewall just above the bead of bad tire. Upon examination it looks
like just an 1/8 inch tear in the tube. I read some place that
patching a tube after a sidewall blow out is not a good idea since the
surrounding rubber often has undergone extreme stress. There is no
sign of chafing just the small tear from the burst. Anyone have any
luck patching this kind of blow out?

This morning my nice new thorn resistant tube blew out through the
sidewall just above the bead of bad tire. Upon examination it looks
like just an 1/8 inch tear in the tube. I read some place that
patching a tube after a sidewall blow out is not a good idea since the
surrounding rubber often has undergone extreme stress. There is no
sign of chafing just the small tear from the burst. Anyone have any
luck patching this kind of blow out?

There's generally not enough material to support the load of a patch when
the cut is low on the sidewall. A sidewall patch requires a fair amount of
space on all sides, to spread out the stress and keep it from trying to blow
back out through the hole.

You need to examine the area closely to see what caused the failure, since a
cut that low can sometimes be from a brake pad hitting the tire and wearing
through it. It can also be an indication of riding on too-low air pressure
or bottoming out the tire on a nasty bump (or a combination of the two).

--Mike Jacoubowsky
Chain Reaction Bicycles
www.ChainReaction.com
IMBA, BikesBelong, NBDA member

wrote in message
...
This morning my nice new thorn resistant tube blew out through the
sidewall just above the bead of bad tire. Upon examination it looks
like just an 1/8 inch tear in the tube. I read some place that
patching a tube after a sidewall blow out is not a good idea since the
surrounding rubber often has undergone extreme stress. There is no
sign of chafing just the small tear from the burst. Anyone have any
luck patching this kind of blow out?

On 31 Oct 2004 14:39:36 EST, wrote:

This morning my nice new thorn resistant tube blew out through the
sidewall just above the bead of bad tire. Upon examination it looks
like just an 1/8 inch tear in the tube. I read some place that
patching a tube after a sidewall blow out is not a good idea since the
surrounding rubber often has undergone extreme stress. There is no
sign of chafing just the small tear from the burst. Anyone have any
luck patching this kind of blow out?

Yes. Patch & go. You're probably confusing this with the advice that
a tubeless automobile tire which has had a sidewall puncture is not
repairable. Tubes have no such restriction.

OTOH, look for the cause. I'm assuming that the tire is one that has
been in service for some time, not a new unit, but the tube was
freshly installed. If that's the case, then the most likely cause is
that a fold of the tube was caught between the bottom of the tire bead
and the rim when the tube was installed, and it jacked the tire away
from the rim until it could squeeze past and blow out. If that's what
took place, just be more careful when reinstalling, and don't forget
to inflate the tube just enough to make it round in cross-section
before slipping it into the tire. If the tube failed along a mold
line in the absence of any damage to the tire or evidence that the
tire had crept up off the rim in that area, it's possible that the
tube may be flawed elsewhere as well, but I'd still patch and go.
--
Typoes are a feature, not a bug.
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On Sun, 31 Oct 2004 20:37:59 GMT, "Mike Jacoubowsky/Chain Reaction
Bicycles" wrote:

This morning my nice new thorn resistant tube blew out through the
sidewall just above the bead of bad tire. Upon examination it looks
like just an 1/8 inch tear in the tube. I read some place that
patching a tube after a sidewall blow out is not a good idea since the
surrounding rubber often has undergone extreme stress. There is no
sign of chafing just the small tear from the burst. Anyone have any
luck patching this kind of blow out?

There's generally not enough material to support the load of a patch when
the cut is low on the sidewall. A sidewall patch requires a fair amount of
space on all sides, to spread out the stress and keep it from trying to blow
back out through the hole.

You need to examine the area closely to see what caused the failure, since a
cut that low can sometimes be from a brake pad hitting the tire and wearing
through it. It can also be an indication of riding on too-low air pressure
or bottoming out the tire on a nasty bump (or a combination of the two).

--Mike Jacoubowsky
Chain Reaction Bicycles
www.ChainReaction.com
IMBA, BikesBelong, NBDA member

Thanks! I don't plan on reusing the tire since the casing appears
rotted around the bead. The tube blew through the sidewall casing
above the bead and rim. The rest of the sidewall appears weak and
there is some dark stain on the inside of the casing as if rust from
the bead had leeched through. I will patch and go on the tube.

On Sun, 31 Oct 2004 22:34:27 GMT, Werehatrack
wrote:

On 31 Oct 2004 14:39:36 EST, wrote:

This morning my nice new thorn resistant tube blew out through the
sidewall just above the bead of bad tire.

Ah. Missed that "bad tire" note the first time. My advice: Patch,
replace tire, and go, unless the tube is visibly distorted in the area
to the point that it won't lay flat.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.

On Mon, 01 Nov 2004 00:04:03 GMT, Werehatrack
wrote:

On Sun, 31 Oct 2004 22:34:27 GMT, Werehatrack
wrote:

On 31 Oct 2004 14:39:36 EST, wrote:

This morning my nice new thorn resistant tube blew out through the
sidewall just above the bead of bad tire.

Ah. Missed that "bad tire" note the first time.

When the tire blew out it almost looked like someone had sliced my
sidewall to be mean since the tire was new. Apparantly this was NOS
with the emphasis being on the word Old. They were obviously dry
rotted from age around the beads and the seller should have thought
twice before retailing them.

My advice: Patch,
replace tire, and go, unless the tube is visibly distorted in the area
to the point that it won't lay flat.

No visible distortion in the tube although it must have stretched some
when it bubble gum burst out the sidewall.

"Violence is the last refuge of the incompetent."
-Isaac Asimov

On 01 Nov 2004 12:17:36 EST, wrote:

No visible distortion in the tube although it must have stretched some
when it bubble gum burst out the sidewall.

In my experience, then, with a relatively new tube, you should be OK
to patch. I've had similar experiences when rehabbing bikes acquired
from Goodwill and other such sources; many times the tires are
obviously rotten, but now and then it turns out that they only
*looked* good.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.

On 31 Oct 2004 14:39:36 EST, wrote:

This morning my nice new thorn resistant tube blew out through the
sidewall just above the bead of bad tire. Upon examination it looks
like just an 1/8 inch tear in the tube. I read some place that
patching a tube after a sidewall blow out is not a good idea since the
surrounding rubber often has undergone extreme stress. There is no
sign of chafing just the small tear from the burst. Anyone have any
luck patching this kind of blow out?

Well yes and no. When I was a cheapskate college kid I "patched" a
sidewall blowout with coaches tape, a.k.a. ankle tape. I just wrapped it
around the tire, the rim, and everything. Ugly and out of balance, but
this was a campus bike and it kept me going in an emergency kind of way
until I had enough cash for an overpriced shiny new Schwinn tire from the
local bleed'em-dry guy.
Not a recommended permanent repair, but a fair idea for a "finish-the-ride"
kit.

cheers-

Dan Rea

On Mon, 08 Nov 2004 11:36:50 -0700, DB Rea wrote:

On 31 Oct 2004 14:39:36 EST, wrote:

This morning my nice new thorn resistant tube blew out through the
sidewall just above the bead of bad tire. Upon examination it looks
like just an 1/8 inch tear in the tube. I read some place that
patching a tube after a sidewall blow out is not a good idea since the
surrounding rubber often has undergone extreme stress. There is no
sign of chafing just the small tear from the burst. Anyone have any
luck patching this kind of blow out?

Well yes and no. When I was a cheapskate college kid I "patched" a
sidewall blowout with coaches tape, a.k.a. ankle tape. I just wrapped it
around the tire, the rim, and everything. Ugly and out of balance, but
this was a campus bike and it kept me going in an emergency kind of way
until I had enough cash for an overpriced shiny new Schwinn tire from the
local bleed'em-dry guy.
Not a recommended permanent repair, but a fair idea for a "finish-the-ride"
kit.

cheers-

Dan Rea

I have patched this type blow by wrapping a short piece or tube around the
tube where the cut in the side wall is. This supprts the tube and stops
another blow out. It will be ugly and a bit out of balance and you have
to be carefull of tire pressure but it will get you home. On the Around
the Bay ride in Melbourne a few weeks ago a team mate had a blow out like
this. I had packed a piece of tube about 10cm long in my repair kit.
This got him to Queenscliffe, about 50 - 60 km, where he was able to buy a
new tire. This was on a nearly new bike, only about 900km. The cut was
right next to the bead. It appeared that the tire had cut by rubbing
against the rim. This inside edge of the tube felt quite sharp near the
cut tire.
Another method of patching a cut tire is to use a short piece of old tire
with bead cut off. Of course all this requires that you are carrying
these things with you. On a long ride such as Around the BAy (210 km ) it
pays to carry such things

John Venables

"John Venables" wrote in message
...
On Mon, 08 Nov 2004 11:36:50 -0700, DB Rea wrote:

On 31 Oct 2004 14:39:36 EST, wrote:

This morning my nice new thorn resistant tube blew out through the
sidewall just above the bead of bad tire. Upon examination it looks
like just an 1/8 inch tear in the tube. I read some place that
patching a tube after a sidewall blow out is not a good idea since the
surrounding rubber often has undergone extreme stress. There is no
sign of chafing just the small tear from the burst. Anyone have any
luck patching this kind of blow out?

Well yes and no. When I was a cheapskate college kid I "patched" a
sidewall blowout with coaches tape, a.k.a. ankle tape. I just wrapped it
around the tire, the rim, and everything. Ugly and out of balance, but
this was a campus bike and it kept me going in an emergency kind of way
until I had enough cash for an overpriced shiny new Schwinn tire from the
local bleed'em-dry guy.
Not a recommended permanent repair, but a fair idea for a
"finish-the-ride"
kit.

cheers-

Dan Rea

I have patched this type blow by wrapping a short piece or tube around the
tube where the cut in the side wall is. This supprts the tube and stops
another blow out. It will be ugly and a bit out of balance and you have
to be carefull of tire pressure but it will get you home. On the Around
the Bay ride in Melbourne a few weeks ago a team mate had a blow out like
this. I had packed a piece of tube about 10cm long in my repair kit.
This got him to Queenscliffe, about 50 - 60 km, where he was able to buy a
new tire. This was on a nearly new bike, only about 900km. The cut was
right next to the bead. It appeared that the tire had cut by rubbing
against the rim. This inside edge of the tube felt quite sharp near the
cut tire.
Another method of patching a cut tire is to use a short piece of old tire
with bead cut off. Of course all this requires that you are carrying
these things with you. On a long ride such as Around the BAy (210 km ) it
pays to carry such things

John Venables

I also had to be a cheapskate and patched tires on the inside with bits of
sidewall from old tires. Rubber cement won't work. Use contact cement (can
be found at a hardware store). Make sure the patch goes well beyond the cut.

The trick I've heard of to get you home when you're not prepared for this is
to wrap a dollar bill around the spare tube. Never tried it though.

--Art