Tire Pressure gage

On Sat, 26 Apr 2014 02:21:22 GMT, Ralph Barone
wrote:

John B. wrote:
On Fri, 25 Apr 2014 10:29:14 -0500, AMuzi wrote:

On 4/25/2014 9:09 AM, jbeattie wrote:
On Friday, April 25, 2014 5:33:22 AM UTC-7, AMuzi wrote:
On 4/25/2014 6:18 AM, John B. wrote:



(previously posted to rec.bicycles.soc by mistake)



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.





The better Bourdon tube style gauges bleed an absolute

minimum of air when checking:

http://www.yellowjersey.org/panag2.jpg


Crap, man, that tire is running at like 400 psi! (Really, though, what
is the scale used by the Japanese?)

-- Jay Beattie.


Soft tire, looks about 70 psi. The rest of the world is on
the CGS system, in this case bar. One atmosphere is about
14.7psi. Your race tires run something like 7-1/2 of those.

in re CGS:
I only learned last year that kilopascals are almost but not
quite bar dammit:
http://www.wolframalpha.com/input/?i=Bar+to+KPa

Yikes! that's a mess isn't it? Makes a good defense for
furlongs and troy ounces and such.

1 Bar = 100 kPa.

101.3, if I recall correctly.

I don't know, I have to look them up on a chart. But three charts, so
far, all say 1 bar = 100 kPa..... for whatever that's worth :-)
--
Cheers,

John B.

yeah that's another reason for going global digital so you know what 75 psi is in acre-feet

On Saturday, April 26, 2014 7:57:43 AM UTC-4, DATAKOLL MARINE RESEARCH wrote:

yeah that's another reason for going global digital so you know what 75 psi is in acre-feet

use this link...the original


http://www.onlineconversion.com/volume.htm

http://www.onlineconversion.com/volume.htm



100 jigger = 0.018 601 190 476 hogshead [US]

John B. wrote:
On Sat, 26 Apr 2014 02:21:22 GMT, Ralph Barone
wrote:

John B. wrote:
On Fri, 25 Apr 2014 10:29:14 -0500, AMuzi wrote:

On 4/25/2014 9:09 AM, jbeattie wrote:
On Friday, April 25, 2014 5:33:22 AM UTC-7, AMuzi wrote:
On 4/25/2014 6:18 AM, John B. wrote:



(previously posted to rec.bicycles.soc by mistake)



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.





The better Bourdon tube style gauges bleed an absolute

minimum of air when checking:

http://www.yellowjersey.org/panag2.jpg


Crap, man, that tire is running at like 400 psi! (Really, though, what
is the scale used by the Japanese?)

-- Jay Beattie.


Soft tire, looks about 70 psi. The rest of the world is on
the CGS system, in this case bar. One atmosphere is about
14.7psi. Your race tires run something like 7-1/2 of those.

in re CGS:
I only learned last year that kilopascals are almost but not
quite bar dammit:
http://www.wolframalpha.com/input/?i=Bar+to+KPa

Yikes! that's a mess isn't it? Makes a good defense for
furlongs and troy ounces and such.

1 Bar = 100 kPa.

101.3, if I recall correctly.

I don't know, I have to look them up on a chart. But three charts, so
far, all say 1 bar = 100 kPa..... for whatever that's worth :-)

No, you're right. I had a vague recollection that 1bar = 1 atm = 14.7 psi =
101.3 kPa = 760 torr, but further searching shows that 1 bar = 100 kPa. The
only thing I can find in defence of my original statement is this
http://physics.stackexchange.com/questions/74198/why-was-the-conversion-factor-of-the-metric-unit-bar-chosen-the-way-it-was
, which appears to imply that the bar was redefined at some point (talk
about moving the bar).

1. torr
tôr/
noun
noun: torr; plural noun: torr
1. 1.
a unit of pressure used in measuring partial vacuums, equal to 133.32 pascals.
Origin

1940s: named after E. Torr (see Torricelli, Evangelista).
Translate torr to
Use over time for: torr
nnnnnnnnnnnnnnnnnnnB

The torr symbol is a non-SI unit of pressure with a ratio of 760 to 1 in standard atmospheres. This is roughly equal to the fluid pressure exerted by a millimeter

http://en.wikipedia.org/wiki/Torr

ah yes Toricelli !

roughly

ungh oh sure all NASA's instruments pointed toward the red shift are analog...no prob.

joining the vacuum tubes are warmer set isnot in odor. I hear (digitally) tubes are big at Civil War reenactments.

try a digital primer.

or filter thru

https://www.google.com/#q=analog+mea...+measur ement