Tire Pressure Gage
 

I have a pressure gage on my tire pump but have been wondering about
whether a separate pressure gage might not be helpful. 700C 28 or 32,
presta valve, tires, at ~90 - 100 psi, and I've pumped them up
approximately every one to two weeks mainly based on the "Squeeze
Test".

I've noticed that connecting the tire pump to the tire and pumping
that the air pressure in the pump and hose rise until they overcome
the tire valve and for an instant the approximate tire pressure is
registered and sometimes if I had known the tire pressure I wouldn't
have used the pump. Thus the thought that a gage might be useful.

On the other hand, it does take a finite amount of air to operate the
gage so each time one checks the pressure it reduced the tire pressure
by some figure.

So the question is whether using the gage with 28 - 32mm tires is
going to cause a significant pressure loss over, say 4 or 5 checks and
will it, in fact, result in fewer pump-ups... not that pumping up
tires is really that onerous a task :-)
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Cheers,

John B.

Tire Pressure Gage
 

On 4/24/2014 11:31 PM, John B. wrote:

I have a pressure gage on my tire pump but have been wondering about
whether a separate pressure gage might not be helpful. 700C 28 or 32,
presta valve, tires, at ~90 - 100 psi, and I've pumped them up
approximately every one to two weeks mainly based on the "Squeeze
Test".

I've noticed that connecting the tire pump to the tire and pumping
that the air pressure in the pump and hose rise until they overcome
the tire valve and for an instant the approximate tire pressure is
registered and sometimes if I had known the tire pressure I wouldn't
have used the pump. Thus the thought that a gage might be useful.


If you tap the presta valve before pumping to break the air seal doesn't
this get rid of this problem? Or am I missing something?

On the other hand, it does take a finite amount of air to operate the
gage so each time one checks the pressure it reduced the tire pressure
by some figure.

So the question is whether using the gage with 28 - 32mm tires is
going to cause a significant pressure loss over, say 4 or 5 checks and
will it, in fact, result in fewer pump-ups... not that pumping up
tires is really that onerous a task :-)

Tire Pressure Gage
 

On Fri, 25 Apr 2014 08:06:48 -0400, Duane
wrote:

On 4/24/2014 11:31 PM, John B. wrote:

I have a pressure gage on my tire pump but have been wondering about
whether a separate pressure gage might not be helpful. 700C 28 or 32,
presta valve, tires, at ~90 - 100 psi, and I've pumped them up
approximately every one to two weeks mainly based on the "Squeeze
Test".

I've noticed that connecting the tire pump to the tire and pumping
that the air pressure in the pump and hose rise until they overcome
the tire valve and for an instant the approximate tire pressure is
registered and sometimes if I had known the tire pressure I wouldn't
have used the pump. Thus the thought that a gage might be useful.


If you tap the presta valve before pumping to break the air seal doesn't
this get rid of this problem? Or am I missing something?

I was trying to point out that sometimes when I used the pump I didn't
need to. But yes, poking the valve stem enough to "un stick" it makes
it easier .

On the other hand, it does take a finite amount of air to operate the
gage so each time one checks the pressure it reduced the tire pressure
by some figure.

So the question is whether using the gage with 28 - 32mm tires is
going to cause a significant pressure loss over, say 4 or 5 checks and
will it, in fact, result in fewer pump-ups... not that pumping up
tires is really that onerous a task :-)



--
Cheers,

John B.

Tire Pressure Gage
 

- John B. / Fri, 25 Apr 2014 05:31:36 +0200


Better idea: get an adapter for car-type valves and check
the pressure at the gas-station. Many manometers sold for bikes
have toy quality - even expensive ones tend to show phantasy values.

With the French type valves you use (which are good), presure
can only be checked by filling to a higher level. These valves are
made for high-pressure slim racing tires which have to refilled
quite often anyways, so ther is no test-mode intended by design.



jk





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no sig