Recurring flat tires (paranormal?)

Tin Gherdanarra said:

What am I doing wrong?

I always get punctures in the tube of my bicycle's
rear wheel, and only the rear wheel. Often I get no
further than a mile. My current bicycle is a TREK
carbon with aluminium rims, but I had this problem with
my previous three
bikes as well (among them heavy-duty mountain bikes).
I tried all available brands of tubes, all sorts
of tires, checked for splinters and pieces of
broken glass in the tires (with a magnifying glass),
had experts change the tape around the rim and changed
the entire rim. All with the result that I'm a nervous
wreck. My driving style has no effect on the phenomenon;
and I'm not a very aggressive cyclist to begin with
(chain smoker).

Maybe I should have crossposted this question on
alt.religion.exorcism or something; downloading
more than 500 headers from this newsgroup always
crashes my Thunderbird. A bad omen.
Does anyone have experience with "The spirit of
christ compels you" and flat tires?

It's the chain smoking.

--
Ted Bennett

Ted Bennett said:

Tin Gherdanarra said:

What am I doing wrong?

I always get punctures in the tube of my bicycle's
rear wheel, and only the rear wheel. Often I get no
further than a mile. My current bicycle is a TREK
carbon with aluminium rims, but I had this problem with
my previous three
bikes as well (among them heavy-duty mountain bikes).
I tried all available brands of tubes, all sorts
of tires, checked for splinters and pieces of
broken glass in the tires (with a magnifying glass),
had experts change the tape around the rim and changed
the entire rim. All with the result that I'm a nervous
wreck. My driving style has no effect on the phenomenon;
and I'm not a very aggressive cyclist to begin with
(chain smoker).

Maybe I should have crossposted this question on
alt.religion.exorcism or something; downloading
more than 500 headers from this newsgroup always
crashes my Thunderbird. A bad omen.
Does anyone have experience with "The spirit of
christ compels you" and flat tires?

It's the chain smoking.

Your are awful. That can't be right, because other
chain-smokers I know have tires that work just fine.

--
Lisp kann nicht kratzen, denn Lisp ist fluessig

Tin Gherdanarra said:

I always get punctures in the tube of my bicycle's
rear wheel, and only the rear wheel. Often I get no
further than a mile. My current bicycle is a TREK
carbon with aluminium rims,

First, you have to determine what exactly is causing the flats.
Something certainly is. Could be glass, thorns, small pieces of wire,
etc. Or you may be getting pinch flats if you are heavy or aren't
running enough pressure in the tires.

Give us some more info. Are the punctures all at the same location on
the tube? Do you find evidence of glass? What size / width are the
tires, and how much pressure?

It's a good idea to align the tire label with the rim's valve hole.
Then you can determine the place on the tire that corresponds to the
puncture on the rim, and search for the cause.

All other things being equal, you can expect to get more flats in the
rain than in dry weather

ArtHarris

Tin Gherdanarra said:

What am I doing wrong?

I always get punctures in the tube of my bicycle's
rear wheel, and only the rear wheel. Often I get no
further than a mile.

Do these flats happen when you start from a specific place (i.e. your
home)? If so, look there first. Many flats happen after a tyre has
carried a sharp object around for a while before it works its way
through the tube.

--
Dave
dvt at psu dot edu

Everyone confesses that exertion which brings out all the powers of body
and mind is the best thing for us; but most people do all they can to
get rid of it, and as a general rule nobody does much more than
circumstances drive them to do. -Harriet Beecher Stowe, abolitionist and
novelist (1811-1896)

Tin Gherdanarra said:

Art Harris wrote:
Thanks for your support, but I think the problem
must be something subtle and systemic, but I'm
pretty much out of explanations.

Really only three possibilities:

1) Something sharp is penetrating the tire.
2) Something inside (spoke, burr on rim, etc.) is puncturing or wearing
the tube.
3) Pinch flat (Tire "bottoms out"against the rim when hitting a
pothole, especially for an underinflated tire or heavy rider).

Quoted message said:

Quoted message said:

Could be glass, thorns, small pieces of wire,

This must be something really microscopic. And it
must hop from tire to tire and from bike to bike.

Run your thumb around the inside of the tire to find the culprit. If
you don't find what caused the flat, it will cause another.

Quoted message said:

Quoted message said:

Or you may be getting pinch flats

That was suggested by almost all the bicycle repair shop folks
I talked to: Don't use clasps to fit the tire back on the rim
after changing the tube, because it could harm the tube.

No, I'm talking about the tube getting pinched against the rim while
riding when hitting a pothole. Pinch flats usually leave two small
holes (snake bite). The skinnier the tire and heavier the rider, the
more likely pinch flats become.

Art Harris

"Ted Bennett" wrote: It's the chain smoking.
^^^^^^^^^^^^^^^
I tried to replicate those conditions by riding my bike as fast as I could,
but I simply could not get the chain hot enough to produce even a wisp. I
does make sense, though, since it is affecting only the rear wheel. Are you
using a chain guard? Maybe, if you removed it for better cooling......

Tin Gherdanarra said:

Art Harris wrote:

Quoted message said:

Quoted message said:

All other things being equal, you can expect to get more flats in the
rain than in dry weather

That's a new one, too. But why? Moisture should soften
thorns, for example.

Several reasons. The main one is probably that water is a good
lubricant and makes it easier for a given piece of glass or other sharp
object to penetrate the tire. Take an old tube and cut it with a knife
noting how much pressure is required. Then try wetting the tube first
and cut it again. Other reasons include: rain washes debris (incl.
glass and thorns) into the traveled part of the roadway; such debris is
harder to spot and avoid when the road is wet; debris tends to stick
better to wet tires and gets carried around for a few revolutions
therefore making it more likely that a sharp edge will be pushed into
the tire; and potholes are harder to spot when they're filled with
water so you may get more pinch flats.

Flats are also much more common on rear tires than front tires as you
have observed. The rear tire is more heavily loaded making it more
likely to pinch flat on hitting potholes or other sharp bumps and it
also compresses more and therefore covers a wider area on the road
surface. But the biggest reason is that thorns, glass shards, and thin
wires (from worn car tires) tend to lie flat on the road surface until
the front tire runs over them and knocks them into position for the
rear tire to hit.

As others suggested, the first step is to determine the main cause of
your flats. Are they single pinholes in the tube or do they come in
pairs of little slits? The latter would suggest a pinch flat from
hitting a pothole or bump. Are they located under the tread of the
tire (i.e. something from outside caused the puncture) or are they
located on the part of the tube that's in contact with the rim?

Tin Gherdanarra said:

Quoted message said:

if you are heavy or aren't
running enough pressure in the tires.

This is a delicate issue because I tried various pressures.
Some experts even recommended 8 ats. It felt like riding
on the bare metal. I could feel every pebblestone and could
even tell whether a coin on the ground was head or tail.
The other extreme was a friend who has been riding her
Wal-Mart bike (85 Dollars) with 3 ats for years. That felt
spongy and not right either. The other experiments were between
those extremes.

Given that your rims standed 8 bars, your tires should be 23mm or 25mm
- am I right?
Size DOES matter much for pinch (pothole-related) flats, with a 2-holes
pattern (skane-bite-like) in the tube. Pressure also does, and for
other kinds of flats too.
If they're less than 28mm, then don't ride under something like 5-6
bars for 25mm, 6-7 for 23mm, given you weight an average (for Europeans
;o) 75kg.
If these pressures are not comfortable enough, buy fatter tires (28mm
may allow 4-5 bars, 35mm 3 bars...).

Good luck!

Quoted message said:

Tin Gherdanarra said:

Quoted message said:

if you are heavy or aren't
running enough pressure in the tires.

This is a delicate issue because I tried various pressures.
Some experts even recommended 8 ats. It felt like riding
on the bare metal. I could feel every pebblestone and could
even tell whether a coin on the ground was head or tail.
The other extreme was a friend who has been riding her
Wal-Mart bike (85 Dollars) with 3 ats for years. That felt
spongy and not right either. The other experiments were between
those extremes.

Given that your rims standed 8 bars, your tires should be 23mm or 25mm
- am I right?
Size DOES matter much for pinch (pothole-related) flats, with a 2-holes
pattern (skane-bite-like) in the tube. Pressure also does, and for
other kinds of flats too.
If they're less than 28mm, then don't ride under something like 5-6
bars for 25mm, 6-7 for 23mm, given you weight an average (for Europeans
;o) 75kg.
If these pressures are not comfortable enough, buy fatter tires (28mm
may allow 4-5 bars, 35mm 3 bars...).

Good luck!

Hi, for the OP [I didn't save original posts], more questions.

Does this happen when the bike shop installs a new tube?

Do you check tire pressure before each ride, and pump up when needed?

Do you patch and reuse the tubes?

Are they always the same brand and weight of tube?

Have you tried any heavy duty tubes?

I believe someone else asked, but, what size are the tires?
What pressure do you run in them?
What brand/model are the tires?
What do you weigh?

Answer the above questions and perhaps someone will be able to help.
I will say that proper pressure is determined by tire size and then by
what the manufacturer recommends. They usually give a maximum and a
recommended.

Life is Good!
Jeff

Leo Lichtman said:

"Ted Bennett" wrote: It's the chain smoking.
^^^^^^^^^^^^^^^
I tried to replicate those conditions by riding my bike as fast as I could,
but I simply could not get the chain hot enough to produce even a wisp. I
does make sense, though, since it is affecting only the rear wheel. Are you
using a chain guard? Maybe, if you removed it for better cooling......

Leo, were you that guy sitting in the back of the class, always cracking
wise?

--
Ted Bennett

Tin Gherdanarra said:

What am I doing wrong?

I always get punctures in the tube of my bicycle's
rear wheel, and only the rear wheel. Often I get no
further than a mile. My current bicycle is a TREK
carbon with aluminium rims, but I had this problem with
my previous three
bikes as well (among them heavy-duty mountain bikes).
I tried all available brands of tubes, all sorts
of tires, checked for splinters and pieces of
broken glass in the tires (with a magnifying glass),
had experts change the tape around the rim and changed
the entire rim. All with the result that I'm a nervous
wreck. My driving style has no effect on the phenomenon;
and I'm not a very aggressive cyclist to begin with
(chain smoker).

Maybe I should have crossposted this question on
alt.religion.exorcism or something; downloading
more than 500 headers from this newsgroup always
crashes my Thunderbird. A bad omen.
Does anyone have experience with "The spirit of
christ compels you" and flat tires?

--
Lisp kann nicht kratzen, denn Lisp ist fluessig

The fact is that on the overall picture I rarely get flats. But when I
do it's usually a whole bunch in a short time.

Here's what I do:
When installing a new tube/ tire. I mark the outside of the tire w/ a
radial line on both sides of the tire @ the valve stem w/ a blue Bic
pen. (The marks last forever)

Then I mark the tube @ the valve stem w/ a radial line and an arrow
coming from it in the direction of rotation on both sides

I talcum powder the tube. (Regardless of what Jobst says. It can't
hurt, & I believe it helps. It's a religious thing.)

Check the inside of each rim for any minor protrusions @ spoke hoses /
valve area. Even the minorest of protrusions are smoothed w/ a Dremel
Toll; a file, a deburring tool, whatever it takes. It's absolutely
amazing how small of a roughness can cause a flat on road tires &
tubes, even w/ Velox tape.

Then I try to get away w/ just one layer of Velox tape. (I will not
install any other brand. I have on occasion used another brand if it
was already on the rim & working OK)

If I'm still getting punctures on the inside of the tube, I try a 2nd
layer of Velox. If I can't get the tire on & off, then I return to
deburring the rim, & 1 layer of Velox.

I use Slime, because not only does it sometimes actually stop minor
leaks, but also due to its fluorescents, it makes it easy to spot the
leak, often before even removing the tube. Before removing the wheel, I
remove any object that may have penetrated the tire from the outside.
Also, I try to get the Slime to work by slowly rotating the wheel &
putting small amounts of air in. Its all the better if I can see the
actual site of the puncture & keep that side mostly down while rotating
the wheel. Often works. If it's leaking out about as fast as I can pump
it, I give up & remove the tube.

If I know the site of the puncture, I take a Bic pen & circle it & also
put a radial mark on the side of the tire to help align the tube on to
the tire to mark the spot of the leak on the tube.

Remove the tube. Try not to use tire leavers.

If I don't know the location of the leak, I inflate the tube, & hold it
next to my cheek & ear & rotate it to find the location. If found,
inspect it to see any clues as to the cause. (Glass, thorn, snake bite,
inside rim abrasion, etc.) And mark the location w/ long lines @ 90
deg. pointing to it.

Assuming I find the leak, I lay the tube on the tire w/ the valve stem
located w/ the line on the tire, & in the correct direction, I mark the
approx. location on the tire & run a paper towel in the area. If I find
the offending object I remove it. Then continue rubbing the paper towel
in one direction all the way around the inside of the tire, looking for
any other perpetrators. If I hadn't previously found the location in
the tube, I run the paper towel all the way around the tire feeling for
the object.

Change to a fresh tested tube carried in a zip loc bag coated w/ talc.

Really try to reinstall tire w/o tire leaver. (More important than when
removing)
Take tube home & patch, & test.

To test I inflate it to ~ 2X size & put it aside to see if it holds it
size for a few days. If it has a slow leak that I can't feel nor hear,
I fill the kitchen sink w/ H2O & slowly rotate, looking for bubbles.

I realize that this is a lot of time & effort, but w/o the steps to
locate the offending object. It's very likely that the fresh tube will
be punctured by it again.

When I hear about someone who changes tubes & removes & reinstalls the
wheel in 45 sec or some such mind boggling time, I have to think that
they must are very lucky to not get more punctures from the original
object.

When I get a flat, it usually seems that it's hot & I'm sweating like a
hog w/ extra sweat in my eyes due to stopping, & if I haven't marked
the tube w/ the direction of rotation, I will invariably loose track of
which side is which.

Good luck, John