Mystery flats

CM

I've been having a series of flats that have baffled me. The wheels are
Krysrium SSL, Tires are Vittoria Corsa CX and tubes are lightweight
Bontrager. Inflation is 120lbs.

They tend to happen on bumpy surfaces at high speed (downhill/fast pace) and
create slow leaks such that the tire is soft but not immediately flat as in
a puncture. When I removed the tube, it's was stuck to the tire. I assumed
these were pinch flats and have used talcum powder on the tubes/tire...maybe
not enough for I'm still getting them. The last flat was post-talcum and
while stuck less, still was adhered to some degree. On first pass, they do
not seem to be in the same place each time.

I like the Corsa as they ride well and are easy to get on and off (obviously
I've had practice lately!). But I don't know if that ease, or not enough
talc (or other suggestions?). I'm even wondering if less pressure would
help? Suggestions?

John Everett

On Wed, 28 Apr 2004 14:14:29 GMT, "CM" <sllywab@yahoo.com> wrote:

>I've been having a series of flats that have baffled me. The wheels are
>Krysrium SSL, Tires are Vittoria Corsa CX and tubes are lightweight
>Bontrager. Inflation is 120lbs.
>
>They tend to happen on bumpy surfaces at high speed (downhill/fast pace) and
>create slow leaks such that the tire is soft but not immediately flat as in
>a puncture. When I removed the tube, it's was stuck to the tire. I assumed
>these were pinch flats and have used talcum powder on the tubes/tire...maybe
>not enough for I'm still getting them. The last flat was post-talcum and
>while stuck less, still was adhered to some degree. On first pass, they do
>not seem to be in the same place each time.
>
>I like the Corsa as they ride well and are easy to get on and off (obviously
>I've had practice lately!). But I don't know if that ease, or not enough
>talc (or other suggestions?). I'm even wondering if less pressure would
>help? Suggestions?

Jobst may indeed chime in here, but talcum makes absolutely no
difference. At the pressures we're dealing with the tube and tire will
not move relative to each other no matter how much talcum (or anything
else for that matter) is involved.

If the problem is pinch flats you might try mounting the tire with
enough air in the tube to make it hold its shape. After mounting
inflate to around 20 psi; then go around the wheel pushing the bead
away from the rim and check to make sure the tube isn't caught. Once
you've assured yourself that all is well, fully inflate.

When you check the flat tube are there two holes next to one another?
If so, then we're dealing with snakebites. Less pressure would only
exacebate this problem. If the problem is snakebikes you might try a
heavier duty tube, or steering around the bumps. :-)


jeverett3<AT>earthlink<DOT>net http://home.earthlink.net/~jeverett3

daveornee

Cm wrote:
> I've been having a series of flats that have baffled me. The wheels are
> Krysrium SSL, Tires are Vittoria Corsa CX and tubes are lightweight
> Bontrager. Inflation is 120lbs.
> They tend to happen on bumpy surfaces at high speed (downhill/fast
> pace) and create slow leaks such that the tire is soft but not
> immediately flat as in a puncture. When I removed the tube, it's was
> stuck to the tire. I assumed these were pinch flats and have used
> talcum powder on the tubes/tire...maybe not enough for I'm still
> getting them. The last flat was post-talcum and while stuck less, still
> was adhered to some degree. On first pass, they do not seem to be in
> the same place each time.
> I like the Corsa as they ride well and are easy to get on and off
> (obviously I've had practice lately!). But I don't know if that ease, or
> not enough talc (or other suggestions?). I'm even wondering if less
> pressure would help? Suggestions?



Check for something causing an internal flat.
1. Make sure there is no part of the tube between the tire bead and the
rim "hook". Partially inflate tube to give it shape before mounting
the tires. Check around both beads 360 degrees before inflating.
2. Check the inside of the tire to make sure there isn't anything that
can wear through the tube. I once had a Specialized tire that had a
small break in the Kevlar belt. A very small Kevlar strand end was
wearing a very small hole in the turbe.
3. Check all around the rim tape to make sure everything is clean,
covered, and smooth.
4. Think about trying another brand of inner tube ... just to
eliminate that variable. I have been through this process a few
times. .... not fun... but when you determine the cause you have
won another battle.



--

jim beam

not all tubes are equal. porosity & splitting are not uncommon if the
rubber is not laid right or cured right. the best quality tubes, imo
are michelin. very high quality of material, excellent consistency of
manufacture. and they have a great valve that easily gives a good seal
on inflation.

CM wrote:
> I've been having a series of flats that have baffled me. The wheels are
> Krysrium SSL, Tires are Vittoria Corsa CX and tubes are lightweight
> Bontrager. Inflation is 120lbs.
>
> They tend to happen on bumpy surfaces at high speed (downhill/fast pace) and
> create slow leaks such that the tire is soft but not immediately flat as in
> a puncture. When I removed the tube, it's was stuck to the tire. I assumed
> these were pinch flats and have used talcum powder on the tubes/tire...maybe
> not enough for I'm still getting them. The last flat was post-talcum and
> while stuck less, still was adhered to some degree. On first pass, they do
> not seem to be in the same place each time.
>
> I like the Corsa as they ride well and are easy to get on and off (obviously
> I've had practice lately!). But I don't know if that ease, or not enough
> talc (or other suggestions?). I'm even wondering if less pressure would
> help? Suggestions?
>
>

S o r n i

CM wrote:
> I've been having a series of flats that have baffled me. The wheels
> are Krysrium SSL, Tires are Vittoria Corsa CX and tubes are
> lightweight Bontrager. Inflation is 120lbs.
>
> They tend to happen on bumpy surfaces at high speed (downhill/fast
> pace) and create slow leaks such that the tire is soft but not
> immediately flat as in a puncture. When I removed the tube, it's was
> stuck to the tire. I assumed these were pinch flats and have used
> talcum powder on the tubes/tire...maybe not enough for I'm still
> getting them. The last flat was post-talcum and while stuck less,
> still was adhered to some degree. On first pass, they do not seem to
> be in the same place each time.
>
> I like the Corsa as they ride well and are easy to get on and off
> (obviously I've had practice lately!). But I don't know if that
> ease, or not enough talc (or other suggestions?). I'm even wondering
> if less pressure would help? Suggestions?

Check the tires for teeny-tiny protrusions.

Bill "sure SOUNDS like very small punctures" S.

Kenny Lee

CM wrote:
> I've been having a series of flats that have baffled me. The wheels are
> Krysrium SSL, Tires are Vittoria Corsa CX and tubes are lightweight
> Bontrager. Inflation is 120lbs.
>
> They tend to happen on bumpy surfaces at high speed (downhill/fast pace) and
> create slow leaks such that the tire is soft but not immediately flat as in
> a puncture. When I removed the tube, it's was stuck to the tire. I assumed
> these were pinch flats and have used talcum powder on the tubes/tire...maybe
> not enough for I'm still getting them. The last flat was post-talcum and
> while stuck less, still was adhered to some degree. On first pass, they do
> not seem to be in the same place each time.
>
> I like the Corsa as they ride well and are easy to get on and off (obviously
> I've had practice lately!). But I don't know if that ease, or not enough
> talc (or other suggestions?). I'm even wondering if less pressure would
> help? Suggestions?
>
>
A piece of glass the size of a grain of sand or it may be a thin piece
of wire sometimes the thickness of a human hair embedded in your tire
could be causing the flats. These objects due to their size at times,
cannot be felt out by sweeping the inside of the tire with your hand.
They make their presence known when you re-inflate the tire back up to
normal pressure and go riding. You won't puncture right away but as you
go about your riding routine they're "grinding away" at your tube
eventually the tire goes "mysteriously" flat. I suggest more careful
inspection of the tire before reuse.

Kenny Lee

Rick Onanian

On Wed, 28 Apr 2004 14:14:29 GMT, "CM" <sllywab@yahoo.com> wrote:
>They tend to happen on bumpy surfaces at high speed (downhill/fast pace) and
>create slow leaks such that the tire is soft but not immediately flat as in
>a puncture. When I removed the tube, it's was stuck to the tire. I assumed
>these were pinch flats and have used talcum powder on the tubes/tire...maybe

Er...you haven't actually located the leaks on the tubes? Autopsy a
tube and post the results.

In the future, you might consider identifying the cause of the
problem before just throwing another tube in a tire that may have
something (like a michelin wire) stuck in it.
--
Rick Onanian

jobst.brandt@stanfordalumni.org

John Everett writes:

>> I've been having a series of flats that have baffled me. The
>> wheels are Krysrium SSL, Tires are Vittoria Corsa CX and tubes are
>> lightweight Bontrager. Inflation is 120lbs.

>> They tend to happen on bumpy surfaces at high speed (downhill/fast
>> pace) and create slow leaks such that the tire is soft but not
>> immediately flat as in a puncture. When I removed the tube, it's
>> was stuck to the tire. I assumed these were pinch flats and have
>> used talcum powder on the tubes/tire... maybe not enough for I'm
>> still getting them. The last flat was post-talcum and while stuck
>> less, still was adhered to some degree. On first pass, they do not
>> seem to be in the same place each time.

>> I like the Corsa as they ride well and are easy to get on and off
>> (obviously I've had practice lately!). But I don't know if that
>> ease, or not enough talc (or other suggestions?). I'm even
>> wondering if less pressure would help? Suggestions?

> Jobst may indeed chime in here, but talcum makes absolutely no
> difference. At the pressures we're dealing with the tube and tire
> will not move relative to each other no matter how much talcum (or
> anything else for that matter) is involved.

> When you check the flat tube are there two holes next to one
> another? If so, then we're dealing with snakebites. Less pressure
> would only exacerbate this problem. If the problem is snakebites
> you might try a heavier duty tube, or steering around the bumps.

....and Bott's Dots. Get 25mm cross section tires!

http://draco.acs.uci.edu/rbfaq/FAQ/8b.11.html

A snake bite can be identified by the embossed casing cord texture
that surrounds the puncture and is visible with grazing incident
light. This effect has helped disprove legal claims against bicycle
shops that were accused of installing tube damaging rim tapes.

Jobst Brandt
jobst.brandt@stanfordalumni.org

ZeeExSixAre

Rick Onanian wrote:
> On Wed, 28 Apr 2004 14:14:29 GMT, "CM" <sllywab@yahoo.com> wrote:
>> They tend to happen on bumpy surfaces at high speed (downhill/fast
>> pace) and create slow leaks such that the tire is soft but not
>> immediately flat as in a puncture. When I removed the tube, it's
>> was stuck to the tire. I assumed these were pinch flats and have
>> used talcum powder on the tubes/tire...maybe
>
> Er...you haven't actually located the leaks on the tubes? Autopsy a
> tube and post the results.
>
> In the future, you might consider identifying the cause of the
> problem before just throwing another tube in a tire that may have
> something (like a michelin wire) stuck in it.

OP, determine where on the tube the puncture is, and if your tires are
mounted with the valve at the label, you can determine where on the tire/rim
the puncture was. Look there for clues.

Check your rim strip, too... my friend has been getting flats due to a
floppy rim strip.

--
Phil, Squid-in-Training

Jeff Wills

Rick Onanian <spamsink@cox.net> wrote in message news:<oojv801mt6093lmethhin7celftjgibnqq@4ax.com>...
> On Wed, 28 Apr 2004 14:14:29 GMT, "CM" <sllywab@yahoo.com> wrote:
> >They tend to happen on bumpy surfaces at high speed (downhill/fast pace) and
> >create slow leaks such that the tire is soft but not immediately flat as in
> >a puncture. When I removed the tube, it's was stuck to the tire. I assumed
> >these were pinch flats and have used talcum powder on the tubes/tire...maybe
>
> Er...you haven't actually located the leaks on the tubes? Autopsy a
> tube and post the results.
>
> In the future, you might consider identifying the cause of the
> problem before just throwing another tube in a tire that may have
> something (like a michelin wire) stuck in it.

Indeed, look at the puncture and then examine where the tube contacted
the tire. I had a series of slow leaks develop- it turned out I had a
slice in the tire *just* big enough to allow a tiny portion of the
tube to poke through. When the tube wore through, it started leaking.
Patched it and it was good for a couple days- then the slow leak
started again. Booted the tire and it was good for a couple months.

Jeff

Rick Onanian

On 28 Apr 2004 15:14:42 -0700, jwills@pacifier.com (Jeff Wills)
wrote:
>Indeed, look at the puncture and then examine where the tube contacted
>the tire. I had a series of slow leaks develop- it turned out I had a
>slice in the tire *just* big enough to allow a tiny portion of the
>tube to poke through. When the tube wore through, it started leaking.
>Patched it and it was good for a couple days- then the slow leak
>started again. Booted the tire and it was good for a couple months.

In fact, I had that exact same thing yesterday. It was riddled with
small cuts on the outside, but I thought they didn't go through.
Well, now they do. When I removed the tire and closely inspected the
inside, I found quite a few of them made it through. I was going to
boot it, but there's too many...

I'll fool around with refurbishing it when I'm bored. I plan to boot
where necessary, and fill in exterior places with either rtv gasket
stuff or Shoe Goo, or maybe Plasti-dip (except, the Plasti-dip I
have is yellow). Any opinions which is better for that purpose?
--
Rick Onanian

Christopher Meyer

Thanks everyone....I'll start working these suggestions as well as return my
baby grandson's talcum powder!


"CM" <sllywab@yahoo.com> wrote in message
news:9%Ojc.12968$eZ5.9825@newsread1.news.pas.earthlink.net...
> I've been having a series of flats that have baffled me. The wheels are
> Krysrium SSL, Tires are Vittoria Corsa CX and tubes are lightweight
> Bontrager. Inflation is 120lbs.
>
> They tend to happen on bumpy surfaces at high speed (downhill/fast pace)
and
> create slow leaks such that the tire is soft but not immediately flat as
in
> a puncture. When I removed the tube, it's was stuck to the tire. I
assumed
> these were pinch flats and have used talcum powder on the
tubes/tire...maybe
> not enough for I'm still getting them. The last flat was post-talcum and
> while stuck less, still was adhered to some degree. On first pass, they
do
> not seem to be in the same place each time.
>
> I like the Corsa as they ride well and are easy to get on and off
(obviously
> I've had practice lately!). But I don't know if that ease, or not enough
> talc (or other suggestions?). I'm even wondering if less pressure would
> help? Suggestions?
>
>

Jeff Wills

Rick Onanian <spamsink@cox.net> wrote in message news:<rtc09052sctjsenngdsmc6vdhrign5a21e@4ax.com>...
> On 28 Apr 2004 15:14:42 -0700, jwills@pacifier.com (Jeff Wills)
> wrote:
> >Indeed, look at the puncture and then examine where the tube contacted
> >the tire. I had a series of slow leaks develop- it turned out I had a
> >slice in the tire *just* big enough to allow a tiny portion of the
> >tube to poke through. When the tube wore through, it started leaking.
> >Patched it and it was good for a couple days- then the slow leak
> >started again. Booted the tire and it was good for a couple months.
>
> In fact, I had that exact same thing yesterday. It was riddled with
> small cuts on the outside, but I thought they didn't go through.
> Well, now they do. When I removed the tire and closely inspected the
> inside, I found quite a few of them made it through. I was going to
> boot it, but there's too many...
>
> I'll fool around with refurbishing it when I'm bored. I plan to boot
> where necessary, and fill in exterior places with either rtv gasket
> stuff or Shoe Goo, or maybe Plasti-dip (except, the Plasti-dip I
> have is yellow). Any opinions which is better for that purpose?

Sounds like a job for... Mr Tuffy!!!

Actually, I've used slightly battered tires (small cuts, as above) for
my beater bike after tossing in a Mr. Tuffy. Quicker and less messy
than Shoe-Goo or Plasti-Dip.

Jeff