presta valve screws out

On Sun, 12 Sep 2004 16:59:30 -0400, "Chuck Davis"
wrote:


wrote in message
.. .
.....
As for valve extenders, I found them so annoying that I
switched to long valve stems after fooling around with
teflon tape to seal the threads.

Another problem is that the extender is just a hollow shell
that fits down over the real Presta valve, whose lock-nut
must be left unscrewed, leaving nothing but air-pressure to
seal the valve.

In addition to the obvious problem of losing air-pressure
without a lock-nut, the extender makes it hard to break a
stuck valve free.

This can cause two problems. First, you can't pump the tube
any further if the valve sticks on a mostly-filled tube.
Second, you can't let the air out to collapse a slow-leak
flat to remove the tire.

So you have to remove and replace the extender, an awkward
job, or else carry something to poke down into it to free
the hidden Presta valve.

In general, most small adaptors, extenders, and adjustable
devices fail to work as well as the real things whose
specific purpose they are meant to imitate.

Carl Fogel


If you use an extender such as:

http://www.worldclasscycles.com/valv...nsion_tube.htm

you'll find that they have a valve control that allows you to open and close
the valve. The metal extenders do need an O-ring or Teflon tape for a good
seal on the valve, but plastic versions of this type of extender will seal
as is.

Chuck Davis


Dear Chuck,

Assuming that they work, those valve extenders add a nice
feature, but at $26 plus shipping for a pair of 50 mm
extenders, I'd be looking for tubulars with long stems if I
used tubulars.

If you know where to find the easier-sealing plastic version
of these valve-extenders with valve-controls, I imagine that
some tubular enthusiasts reading this thread would be
pleased to see the link.

Carl Fogel

Tufo tubulars don't come with long valves. They have the removal valve nut,
and you remove that, put their extender in there via screwing in using the
valve threads on the inside of the tube valve and screw the presta valve
insert into the top of the extension. works marvelously - no teflon tape
required.

david

wrote in message
...
On Sun, 12 Sep 2004 16:59:30 -0400, "Chuck Davis"
wrote:
........
If you use an extender such as:

http://www.worldclasscycles.com/valv...nsion_tube.htm

you'll find that they have a valve control that allows you to open and
close
the valve. The metal extenders do need an O-ring or Teflon tape for a
good
seal on the valve, but plastic versions of this type of extender will seal
as is.

Chuck Davis


Dear Chuck,

Assuming that they work, those valve extenders add a nice
feature, but at $26 plus shipping for a pair of 50 mm
extenders, I'd be looking for tubulars with long stems if I
used tubulars.

If you know where to find the easier-sealing plastic version
of these valve-extenders with valve-controls, I imagine that
some tubular enthusiasts reading this thread would be
pleased to see the link.

Carl Fogel

Carl,

You can find the plastic version on one of my rear wheels. The only link
pointing to it is part of my chain. 8) I bought the extender in 1997 when
I bought a Spinergy wheel. I looked for plastic extenders again lately and
was only able to find metal extenders (with the core I mentioned.) Yes, they
do work and they work quite well. I found them at Nashbar for $9 each, but
they're not listed there anymore.

I ran across this interesting tip at
http://www.bookcase.com/faq/bicycles-faq/part3:

"Another tip.For those with deep dish rims requiring valve extenders, place
a small amount of loctite on the tube valve stem threads and then screw the
valve extender on. This will prevent any leaking at that junction once the
tire is glued on."

As I think about it, it seems that a little Loctite on each valve would be
enough to get a seal for each tire or tube that you have. If you want to
save money, you could get ONE metal extender with the core and a plastic one
without. Use the plastic one to inflate the tire and use the metal one to
close the valve. In that case, you won't need any seal for the metal
extender.

Chuck Davis

(Mark) aszonygya:
:Hi Paul, Were these tubes that have "slime" (Flat sealer) already
:applies to them? I know with these type tubes they generally have to
:have a means to be able to insert the sealer compound, and therefore,
:the Presta Valve screws apart to do this. perhaps to prevent them
:from coming apart ever again, apply some Loctite thread locking
:compound on the threads, and let it dry for a good 42 hours before
:refilling with air, and using. Mark

Nope. Plain vanilla 700 mm 19-25 mm tubes. Loctite? Great idea. I happen to
have a small tube of it. Best regards, Paul

On 12 Sep 2004 13:44:43 GMT, (Paul Nevai) wrote:

So when this thingie can be screwed out, is this a "lower" or "higher"
quality indicator.

It's a difference, and some people like and/or need them, but unless
you have a use for the feature, it's not an advantage.

Also, how can I screw it in so it would never ever screw out again, I tried
to wrap a rubber piece around it and then use a wise grip plier but I am not
sure it worked.

I'd just put a drop of Loctite on it.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.

On Sun, 12 Sep 2004 20:48:36 -0400, "Chuck Davis"
wrote:


wrote in message
.. .
On Sun, 12 Sep 2004 16:59:30 -0400, "Chuck Davis"
wrote:
........
If you use an extender such as:

http://www.worldclasscycles.com/valv...nsion_tube.htm

you'll find that they have a valve control that allows you to open and
close
the valve. The metal extenders do need an O-ring or Teflon tape for a
good
seal on the valve, but plastic versions of this type of extender will seal
as is.

Chuck Davis


Dear Chuck,

Assuming that they work, those valve extenders add a nice
feature, but at $26 plus shipping for a pair of 50 mm
extenders, I'd be looking for tubulars with long stems if I
used tubulars.

If you know where to find the easier-sealing plastic version
of these valve-extenders with valve-controls, I imagine that
some tubular enthusiasts reading this thread would be
pleased to see the link.

Carl Fogel

Carl,

You can find the plastic version on one of my rear wheels. The only link
pointing to it is part of my chain. 8) I bought the extender in 1997 when
I bought a Spinergy wheel. I looked for plastic extenders again lately and
was only able to find metal extenders (with the core I mentioned.) Yes, they
do work and they work quite well. I found them at Nashbar for $9 each, but
they're not listed there anymore.

I ran across this interesting tip at
http://www.bookcase.com/faq/bicycles-faq/part3:

"Another tip.For those with deep dish rims requiring valve extenders, place
a small amount of loctite on the tube valve stem threads and then screw the
valve extender on. This will prevent any leaking at that junction once the
tire is glued on."

As I think about it, it seems that a little Loctite on each valve would be
enough to get a seal for each tire or tube that you have. If you want to
save money, you could get ONE metal extender with the core and a plastic one
without. Use the plastic one to inflate the tire and use the metal one to
close the valve. In that case, you won't need any seal for the metal
extender.

Chuck Davis

Dear Chuck,

This is probably not the best time to mention that I have
for years harvested nice metal Schrader valve caps with the
built-in valve-core wrench from a friend's motorcycle, often
right in front of him when we're checking motorcycle tire
pressures with the machines on the trailer. (The caps come
off quit easily and look much better on my tubes than on
his.)

Let's hope that no one admires your 1997 plastic extenders
enough to follow my evil example.

Carl Fogel