Tire Failure

AGRIBOB said:

Recently had a sidewall failure on a Continental 700 x 28 Gatorskin tire. Mounted once and only
once on a Weiman Concave rim it blew at less than 350 miles. The sidewall suffered an inch and a
quarter "cut" right next to the wire bead. The tire material surrounded the inside of the bead but
the bead could be observed from the tire side.

Check for worn brake pads contacting sidewall. If that sounds like a novice mistake, well, I've been
there and done that (long after I should have known better).

In my case, the pads, either initially or as they wore, reached slightly above the top of the rim.
Wear then caused them to overhang the rim with a very thin (i.e. knife edge) shape, and two tires
went quickly before I figured it out with much embarassment.

Regards, Mark Janeba

AGRIBOB said:

Recently had a sidewall failure on a Continental 700 x 28 Gatorskin tire. Mounted once and only
once on a Weiman Concave rim it blew at less than 350 miles. The sidewall suffered an inch and a
quarter "cut" right next to the wire bead. The tire material surrounded the inside of the bead but
the bead could be observed from the tire side.

-snip-

Quoted message said:

The failure was near the valve thus I had not used tire irons in the damaged area to mount
the tire.

-snip-

I was not there. But that is consistent with someone pulling the valve down snugly to the rim before
airing the tire. The tire would have a lump at the valve, which would drag on a brake shoe, fatally.

--
Andrew Muzi www.yellowjersey.org Open every day since 1 April, 1971

Quoted message said:

Check for worn brake pads contacting sidewall.

Thanks Mark, but that wasn't the case. Bob

(AGRIBOB) may have said:

All insights will be appreciated.

Just a wild left-field guess, but is there any chance that the rim tape is doubled in that area, and
that it might have kept the tire bead from seating all the way in at that point? The valve is a
common place for the tape to be overlapped, and if the tape was a bit wider than strictly
necessary...

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Yes, I have a killfile. If I don't respond to something,
it's also possible that I'm busy.
Words processed in a facility that contains nuts.

agribob-<< Recently had a sidewall failure on a Continental 700 x 28 Gatorskin tire. Mounted once
and only once on a Weiman Concave rim it blew at less than 350 miles. >><BR><BR>

Warranty-we have seen a few of these, BUT I think this tire is inappropriate for a 400 pound tandem.
A Top Touring or equivalent is a better choice, IMO-

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 vecchios.comvecchios.comOpen ↗ "Ruote convenzionali costruite eccezionalmente bene"

"AGRIBOB" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Recently had a sidewall failure on a Continental 700 x 28 Gatorskin tire. Mounted once and only
once on a Weiman Concave rim it blew at less than

350

Quoted message said:

miles. The sidewall suffered an inch and a quarter "cut" right next to

the

Quoted message said:

wire bead. The tire material surrounded the inside of the bead but the

bead

Quoted message said:

could be observed from the tire side.

This was on the rear of our tandem. We are a big team 400+ pounds. Tire

was

Quoted message said:

allways inflated to 120 psi and topped off to 120 psi with a borrowed

floor

Quoted message said:

pump the previous day. Two days before we had done a 7% ten mile long

descent.

Quoted message said:

Stopped half way down and felt the rims. The front was only warm to the
touch, could have continued finger contact indefinately. The rear did not

feel

Quoted message said:

warm at all.

The failure was near the valve thus I had not used tire irons in the

damaged

Quoted message said:

area to mount the tire.

When the tire failed we were coasting down a very smooth newly paved road.

I am

Quoted message said:

not aware of us hitting anything there or anywhere else that would have damaged the tire.

Didn't fall but we often go MUCH faster so this incident is disconcerting.

Was

Quoted message said:

it the tire, the rim, the pressure, the heat? All insights will be appreciated.

Thanks in advance, Bob

I'm just a middleweight roadie, but I do lots of miles and I started out doing them on contis. I had
lots of sidewall blowouts. I just figured it was normal. Then I started experimenting with other
tires. I've never had a sidewall blowout since. I think it's a flaw in the Conti design. That's just
my opinion, but I've probably ridden 50,000 miles on other tires since I stopped riding contis and
I've not had a single sidewall cut or blowout.

I also got sick of those little threads peeling off the bead area with the contis. Sometimes I'd
find them wrapped all up in my hubs. Don't know if they still have that aggravating problem.

Bob C.

<snip>

Quoted message said:

I'm just a middleweight roadie, but I do lots of miles and I started out doing them on contis. I
had lots of sidewall blowouts. I just figured it was normal. Then I started experimenting with
other tires. I've never had a sidewall blowout since. I think it's a flaw in the Conti design.

<snip>

Conti's a reasonably good tire, but I have had a large number of sidewall cuts on Gatorskins and I
agree, the sidewall is the Conti's achille's heel (and don't buy 700x25 4-Season GP 3000's either -
the tread lasts about 700 miles).

App

Quoted message said:

agribob- Recently had a sidewall failure on a Continental 700 x 28 Gatorskin tire. Mounted once and
only once on a Weiman Concave rim it blew at less than 350 miles.

No one's mentioned it yet, and I'm not sure it's important, but isn't the Weinmann Concave one of
those rims *without* hooks?

"psycholist" <[email hidden]> wrote in message news:<[email hidden]>...

[snip]

Quoted message said:

I also got sick of those little threads peeling off the bead area with the contis. Sometimes I'd
find them wrapped all up in my hubs. Don't know if they still have that aggravating problem.

Bob C.

Dear Bob,

I had the same annoying-little-thread-peeling problem on low-end Continental tires.

I haven't noticed it on other brands, but I'm curious whether it is (or was) just a
Continental problem.

Carl Fogel

Quoted message said:

Quoted message said:

agribob- Recently had a sidewall failure on a Continental 700 x 28 Gatorskin tire. Mounted once
and only once on a Weiman Concave rim it blew at less than 350 miles.

dianne_1234 said:

No one's mentioned it yet, and I'm not sure it's important, but isn't the Weinmann Concave one of
those rims *without* hooks?

You make a good point: yellowjersey.orgWEINRIMS.JPGOpen ↗

--
Andrew Muzi www.yellowjersey.org Open every day since 1 April, 1971

Quoted message said:

I had the same annoying-little-thread-peeling problem on low-end Continental tires.

I haven't noticed it on other brands, but I'm curious whether it is (or was) just a Continental
problem.

I had more strange failures with conti's than any other brand.

AGRIBOB said:

Recently had a sidewall failure on a Continental 700 x 28 Gatorskin tire. Mounted once and only
once on a Weiman Concave rim it blew at less than 350 miles. The sidewall suffered an inch and a
quarter "cut" right next to the wire bead. The tire material surrounded the inside of the bead but
the bead could be observed from the tire side.

This was on the rear of our tandem. We are a big team 400+ pounds. Tire was allways inflated to
120 psi and topped off to 120 psi with a borrowed floor pump the previous day. Two days before
we had done a 7% ten mile long descent. Stopped half way down and felt the rims. The front was
only warm to the touch, could have continued finger contact indefinately. The rear did not feel
warm at all.

The failure was near the valve thus I had not used tire irons in the damaged area to mount
the tire.

When the tire failed we were coasting down a very smooth newly paved road. I am not aware of us
hitting anything there or anywhere else that would have damaged the tire.

Didn't fall but we often go MUCH faster so this incident is disconcerting. Was it the tire, the
rim, the pressure, the heat? All insights will be appreciated.

Do you get flints where you live? I've seen a couple of tyres - including a Conti GP - ruined by
them. One flint can slash a sidewall for 2-3 inches - those Stone Age dudes knew what they were
doing when they were making cutlery!