Valves separating from inner tubes

MikeT said:

In the past 6 months, I've had to replace 4 (count 'em) inner tubes
that failed just at the base of the valve as I've been pumping up the
tires.

The valves are presta and I'm using a Zefal HPx which locks onto the
valve... am I just a muppet with poor tire-inflation-technique, or a
victim of shoddy inner tubes? It's getting depressing.

Probably the latter, try a differnet brand of tube (or yet another brand).
Also don't use valve lockrings. They can draw the valve too far into the
rim, and it's better to allow the valve to move with the tube as the tube
naturally gets tugged about a bit during tyre fitting, etc, I reckon.

I've had no such failures with Michelin tubes with an HPX pump (but have
done with other tubes, and pumps).

~PB

Pete Biggs said:

MikeT said:

In the past 6 months, I've had to replace 4 (count 'em) inner tubes
that failed just at the base of the valve as I've been pumping up the
tires.

The valves are presta and I'm using a Zefal HPx which locks onto the
valve... am I just a muppet with poor tire-inflation-technique, or a
victim of shoddy inner tubes? It's getting depressing.

Probably the latter, try a differnet brand of tube (or yet another brand).
Also don't use valve lockrings. They can draw the valve too far into the
rim, and it's better to allow the valve to move with the tube as the tube
naturally gets tugged about a bit during tyre fitting, etc, I reckon.

Leaving off the lockring can cause the valve to shift quite a bit from
the vertical as the tube creeps inside the cover. This can place
pressure on the tube/valve junction as well as make it difficult to put
the pump onto the valve, but you are right about it pulling the valve
base into the rim.
Having also experienced a few failures at this point I now make rubber
washers out of old tubes and place them over the valve before fitting
acting as a protection between valve base and the edges of the valve
hole inside the rim.
At least I haven't had such a failure since doing this <searches for
wood to touch>.

John B

Rubber washer - that's a top idea I shall institute shortly. I've had too many failures like this as well.

I had many similar failures, mainly with Specialized tubes, especially
if they'd been lying aroun unused for a while. I don't know if th tubes
were old and rubber starting to perish, or whether overstretching (28mm
being the upper limit of specified for the long-stem tubes) caused the
problem.

I'd advise checking all 'spare' inner tubes annually, at least.

--
Helen D. Vecht: [email hidden]
Edgware.

"Helen Deborah Vecht" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

I had many similar failures, mainly with Specialized tubes, especially
if they'd been lying aroun unused for a while. I don't know if th tubes
were old and rubber starting to perish, or whether overstretching (28mm
being the upper limit of specified for the long-stem tubes) caused the
problem.

I'd advise checking all 'spare' inner tubes annually, at least.

--
Helen D. Vecht: [email hidden]
Edgware.

I had a spate of this once and wondered whether it was the citrus cleaner I
was using it that was somehow affecting the joint. I've never really trusted
citrus cleaners since.

Regards, Bob

bob watkinson said:

I had a spate of this once and wondered whether it was the citrus cleaner I
was using it that was somehow affecting the joint.

Citrus cleaners not popular in Holland, then...

Guy
--
May contain traces of irony. Contents liable to settle after posting.
http://www.chapmancentral.co.uk

88% of helmet statistics are made up, 65% of them at Washington University

"Just zis Guy, you know?" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

bob watkinson said:

I had a spate of this once and wondered whether it was the citrus cleaner
I
was using it that was somehow affecting the joint.

Citrus cleaners not popular in Holland, then...

It maybe your being to subtle for me here Guy, Holland - I live in
Perthshire, forgive me if I'm missing something.

Quoted message said:

Guy
--
May contain traces of irony. Contents liable to settle after posting.
http://www.chapmancentral.co.uk

88% of helmet statistics are made up, 65% of them at Washington University

bob watkinson popped their head over the parapet saw what was going on
and said

Quoted message said:

"Just zis Guy, you know?" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

bob watkinson said:

I had a spate of this once and wondered whether it was the citrus
cleaner I
was using it that was somehow affecting the joint.

Citrus cleaners not popular in Holland, then...

It maybe your being to subtle for me here Guy, Holland - I live in
Perthshire, forgive me if I'm missing something.

Joint is a name commonly applied to "herbal" cigarettes
these "herbs" are not illegal in Holland.

--
yours S

Nihil curo de ista tua stulta superstitione

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

Quoted message said:

bob watkinson popped their head over the parapet saw what was going on
and said

Quoted message said:

"Just zis Guy, you know?" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

On Mon, 11 Oct 2004 16:08:25 +0100, "bob watkinson"
<[email hidden]> wrote:

> I had a spate of this once and wondered whether it was the citrus
> cleaner I
> was using it that was somehow affecting the joint.

Citrus cleaners not popular in Holland, then...

It maybe your being to subtle for me here Guy, Holland - I live in
Perthshire, forgive me if I'm missing something.

Joint is a name commonly applied to "herbal" cigarettes
these "herbs" are not illegal in Holland.

I knew it. Way to subtle for me 🙂

Quoted message said:

--
yours S

Nihil curo de ista tua stulta superstitione

JohnB said:

Leaving off the lockring can cause the valve to shift quite a bit from
the vertical as the tube creeps inside the cover. This can place
pressure on the tube/valve junction as well as make it difficult to put
the pump onto the valve

If there is going to be some creeping, I'd rather the valve creeped with the
tube. It would have to creep a lot before the valve was at a problematic
angle, and that doesn't tend to happen if the tube & tyre is fitted
carefully in the first place, in my experience.

~PB

Helen Deborah Vecht said:

I had many similar failures, mainly with Specialized tubes, especially
if they'd been lying aroun unused for a while. I don't know if th tubes
were old and rubber starting to perish, or whether overstretching (28mm
being the upper limit of specified for the long-stem tubes) caused the
problem.

I'd advise checking all 'spare' inner tubes annually, at least.

--
Helen D. Vecht: [email hidden]
Edgware.

Interestingly my failures were also on Specialized tubes, also on 20-28mm tubes in a 28mm tyre.

Pete Biggs said:

JohnB said:

Leaving off the lockring can cause the valve to shift quite a bit from
the vertical as the tube creeps inside the cover. This can place
pressure on the tube/valve junction as well as make it difficult to put
the pump onto the valve

If there is going to be some creeping, I'd rather the valve creeped with the
tube. It would have to creep a lot before the valve was at a problematic
angle, and that doesn't tend to happen if the tube & tyre is fitted
carefully in the first place, in my experience.

I see a lot of bikes when I take groups for basic maintenance where the
valve is at an extreme angle. Sometimes it is _very_ hard to get the
valve upright enough to fit a pump head. It seems to occur more with
schraeders, perhaps because few fit locknuts on them.

This evening I was with a group of cubs where an inner tube was pulled
completely apart.
However I was trying to fit as many cubs as possible into it ;-)
25 fitted in plus a couple of adults before the tube gave way.

John B

KakenBetaal <[email hidden]>typed

Quoted message said:

Helen Deborah Vecht said:

I had many similar failures, mainly with Specialized tubes, especially
if they'd been lying aroun unused for a while. I don't know if th
tubes
were old and rubber starting to perish, or whether overstretching
(28mm
being the upper limit of specified for the long-stem tubes) caused the
problem.

I'd advise checking all 'spare' inner tubes annually, at least.

--
Helen D. Vecht: [email hidden]
Edgware.

Quoted message said:

Interestingly my failures were also on Specialized tubes, also on
20-28mm tubes in a 28mm tyre.

Since I seldom had the problem with Michelin, I suspect in may be a
Specialized problem. I don't think the way the valve was seated caused
the problem either. The tube failed a short distance - about half an
inch- from the valve stem where the valve stem patch joined the main
body of the tube.

/¯¯¯\
/ \
( O )
\ /
\___/

--
Helen D. Vecht: [email hidden]
Edgware.

JohnB said:

Pete Biggs said:

JohnB said:

Leaving off the lockring can cause the valve to shift quite a bit
from the vertical as the tube creeps inside the cover.

Yes a lockring will prevent shifting but leaving it off doesn't *cause* the
shifting.

Quoted message said:

Quoted message said:

Quoted message said:

This can place
pressure on the tube/valve junction

Maybe during pumping but there would also be strain there from whatever is
causing the shifting.

Quoted message said:

Quoted message said:

Quoted message said:

as well as make it difficult to
put the pump onto the valve

If there is going to be some creeping, I'd rather the valve creeped
with the tube. It would have to creep a lot before the valve was at
a problematic angle, and that doesn't tend to happen if the tube &
tyre is fitted carefully in the first place, in my experience.

I see a lot of bikes when I take groups for basic maintenance where
the valve is at an extreme angle.

I reckon that's because the tyres & tubes weren't fitted properly in the
first place, or the tyre has been used/left in a deflated state.

Quoted message said:

Sometimes it is _very_ hard to get the
valve upright enough to fit a pump head. It seems to occur more with
schraeders, perhaps because few fit locknuts on them.

I know it's very common but using a lockring is a poor solution, I think.
Those people can be taught how to properly fit a tube straight without a
lockring, and to keep their tyres pumped up, then the valve will stay
straight enough.

It's not easy to get it perfect with loose-fitting tyres but the valve
shouldn't end up at an extreme angle if the tube wasn't stretched at on side
of valve during fitting, and the tyre is kept inflated.

Of course I've had valves go very wonky myself, but everything has been fine
after refitting more carefully, all without a lockring. I don't believe
tubes or tyres continue to creep/slip for long once the tyre is properly
inflated. There might be a bit at first while things normalise.

In any case, one trick that really helps alignment is to *start* fitting the
tyre at the valve. Finishing away from the valve does increase risk of
pinching the tube, but that can be avoided if careful.

~PB

Helen Deborah Vecht said:

I had many similar failures, mainly with Specialized tubes, especially
if they'd been lying aroun unused for a while. I don't know if th tubes
were old and rubber starting to perish, or whether overstretching (28mm
being the upper limit of specified for the long-stem tubes) caused the
problem.

I've killed a few specialized tubes in the same manner, I assumed it was
just because I'm using a short valve in a deep section rim but seeing this
it makes you wonder.

Steve

On Tue, 12 Oct 2004 06:20:49 GMT, Steve Peake <[email hidden]>

() said:

Helen Deborah Vecht said:

I had many similar failures, mainly with Specialized tubes, especially
if they'd been lying aroun unused for a while. I don't know if th tubes
were old and rubber starting to perish, or whether overstretching (28mm
being the upper limit of specified for the long-stem tubes) caused the
problem.

I've killed a few specialized tubes in the same manner, I assumed it was
just because I'm using a short valve in a deep section rim but seeing this
it makes you wonder.

SWMBO had a run of flats like this. Velox rim tape (there can be only
one!) cured it, but I can't recall if we changed brands of tube at
that point, too...
--
Matt K.
"Did you play in the garden of Eden? Were the goalkeepers gloves to you tossed?
For it seems to me you're the reason, you're the reason why Paradise lost."

On Tue, 12 Oct 2004 01:50:13 +0100, "Pete Biggs" <p@melonbiggs{remove

fruit}.tc said:

In any case, one trick that really helps alignment is to *start* fitting the
tyre at the valve. Finishing away from the valve does increase risk of
pinching the tube, but that can be avoided if careful.

~PB

I agree with the whole of Pete's post (Peter Post .. wasn't he a team
manager at one time??)

Correct fitting and inflation pressures are they key here. One of the
causes of failure is the sideways pressure exerted by the 'push on'
type pump, (small of large) on the valve stem. I have a high pressure
'mini pump' for out on the road, but carry an adaptor (that small
rubber tube that you screws into the old fashioned type of pump) I use
this between pump and valve to eliminate that sideways pressure.

Preventative maintenance :-)

M

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

Quoted message said:

Helen Deborah Vecht said:

I had many similar failures, mainly with Specialized tubes, especially
if they'd been lying aroun unused for a while. I don't know if th
tubes
were old and rubber starting to perish, or whether overstretching
(28mm
being the upper limit of specified for the long-stem tubes) caused the
problem.

I'd advise checking all 'spare' inner tubes annually, at least.

--
Helen D. Vecht: [email hidden]
Edgware.

Interestingly my failures were also on Specialized tubes, also on
20-28mm tubes in a 28mm tyre.

Hmm - I spot a pattern - all the failures I've had have been with
Specialized tubes too (but 28-38mm tubes in a 34 tyre). I remember
when I first got one that the valve was much longer than usual, so
maybe its a combination of manufacture, too tight a lockring pulling
the whole thing right up to the rim and more leverage on the valve
from the pump.

Might try and find a different brand for my new spares.

Pete Biggs said:

JohnB said:

Pete Biggs said:

"JohnB" wrote:
> Leaving off the lockring can cause the valve to shift quite a bit
> from the vertical as the tube creeps inside the cover.

Yes a lockring will prevent shifting but leaving it off doesn't *cause* the
shifting.

OK. wrong word. Try "result in".
Better?

Quoted message said:

I know it's very common but using a lockring is a poor solution, I think.
Those people can be taught how to properly fit a tube straight without a
lockring, and to keep their tyres pumped up, then the valve will stay
straight enough.

Trying to get the average parent to do proper bike maintenance on their
kid's bike is near impossible. Most haven't a clue, let alone a bike
pump :-(

Quoted message said:

In any case, one trick that really helps alignment is to *start* fitting the
tyre at the valve. Finishing away from the valve does increase risk of
pinching the tube, but that can be avoided if careful.

That's also the easiest way to fit a tyre anyway, IME.
I was unawrae anyone did any different.

John B