Correct Torque value for Presta Valve?

I've seen the light and now use a torque wrench for all threaded
fasteners and bottlecaps.

Unfortunately, I have been unable to find the recommended torque spec
for the little knurled nuts on my Presta valves.

Anybody got a definitive answer?

I've been using 0.0000013 ton/furlongs, but I'm not sure that's quite
correct...

Carapace Completed Umber
McMurdo Bay, Ant.
+--------------------------------------------+
| If it can't be expressed in figures, |
| it is not science; it is opinion. |
| --Robert A. Heinlein |
+--------------------------------------------+

Sheldon Brown wrote:

I've seen the light and now use a torque wrench for all threaded
fasteners and bottlecaps.

Unfortunately, I have been unable to find the recommended torque spec
for the little knurled nuts on my Presta valves.

Anybody got a definitive answer?

I've been using 0.0000013 ton/furlongs, but I'm not sure that's quite
correct...

Carapace Completed Umber
McMurdo Bay, Ant.

I know you're looking for something /quantitative/, Sheldon. I don't
have that, but . . .

I tighten them with increasing force until a slight hissing can be
heard, then back them off 1/16th of a turn.

HTH,

Neil

"Sheldon Brown" wrote: (clip) I've been using 0.0000013 ton/furlongs,
(clip)
^^^^^^^^^^^^^
Where did you find a torque wrench calibrated in ton-furlongs? I spent a
micro-century Googling for it and got nowhere.

On Thu, 14 Jul 2005 13:10:32 -0400, Sheldon Brown
wrote:

I've seen the light and now use a torque wrench for all threaded
fasteners and bottlecaps.

Unfortunately, I have been unable to find the recommended torque spec
for the little knurled nuts on my Presta valves.

Anybody got a definitive answer?

I've been using 0.0000013 ton/furlongs, but I'm not sure that's quite
correct...

Carapace Completed Umber
McMurdo Bay, Ant.

A torque wrench is not needed if you cross-thread the nut and apply
Loctite. Alternately, leave the nut off and crimp a resilient tension
flange in place with sleeve band; no sense not using MIL-spec tech in
such a critical area.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.

Neil Brooks wrote:
Sheldon Brown wrote:

I've seen the light and now use a torque wrench for all threaded
fasteners and bottlecaps.

Unfortunately, I have been unable to find the recommended torque spec
for the little knurled nuts on my Presta valves.

Anybody got a definitive answer?

I've been using 0.0000013 ton/furlongs, but I'm not sure that's quite
correct...

Carapace Completed Umber
McMurdo Bay, Ant.

I know you're looking for something /quantitative/, Sheldon. I don't
have that, but . . .

I tighten them with increasing force until a slight hissing can be
heard, then back them off 1/16th of a turn.

Ahh, a new twist to the old rule of thumb:
"Crank 'er up until she talks to ya and then back her off a bit"

dkl

Sheldon Brown wrote:
I've seen the light and now use a torque wrench for all threaded
fasteners and bottlecaps.
- snip
I've been using 0.0000013 ton/furlongs, but I'm not sure that's quite
correct...

That can't be correct, Sheldon. ton/furlong is not a unit of torque
(which is force through a distance). I can't even figure out what
force per distance might be.

I'd suggest that 6.31×10^-09 ton furlongs might be about correct

John Thurston
Juneau, Alaska

wrote: (clip) I can't even figure out what
force per distance might be.
^^^^^^^^^^^^^^^^
Suppose you set up a lever, which presses upward on a load at some arbitrary
fixed distance from the fulcrum. Now, press down on the lever to create a
lifting force on the load. The amount of lifting force will be proportional
to the distance from the fulcrum, so you have tons/furlong. What could be
more obvious? :-)

On Thu, 14 Jul 2005 13:10:32 -0400, Sheldon Brown
wrote:

I've seen the light and now use a torque wrench for all threaded
fasteners and bottlecaps.

Unfortunately, I have been unable to find the recommended torque spec
for the little knurled nuts on my Presta valves.

Anybody got a definitive answer?

I've been using 0.0000013 ton/furlongs, but I'm not sure that's quite
correct...

Carapace Completed Umber
McMurdo Bay, Ant.
+--------------------------------------------+
| If it can't be expressed in figures, |
| it is not science; it is opinion. |
| --Robert A. Heinlein |
+--------------------------------------------+

Dear Sheld--er, Carapace,

You could use one of these micro-torque wrenches and
experiment with 16-32 inch-ounces:

http://www.specialized.net/ecommerce...t%5Fid=176X200

http://www.jensentools.com/product/g...parent_id=4040

That's 1-2 foot-lbs, roughly the same as your 0.0000013
furlong/tons (1.716 ft-lbs @ 1,320,000 ft-lbs per
ton/furlong).

Thanks for making me finally add furlongs/fortnight and
furlong/tons to my conversion spreadsheet.

Off to see if I can average 53,760 furlongs/fortnight (20
mph @ 1 mph per 2688 furlongs/fortnight).

Just my nickel's worth,

Carl Fogel
Times-Picayune Help Desk

On Thu, 14 Jul 2005 13:10:32 -0400, Sheldon Brown
wrote:

I've seen the light and now use a torque wrench for all threaded
fasteners and bottlecaps.

Unfortunately, I have been unable to find the recommended torque spec
for the little knurled nuts on my Presta valves.

Anybody got a definitive answer?


See the "Presto!" adaptor for the Tork-Grip pliers on p. 8 of the
ShelBroCo catalogue. Fit the adaptor, give the knurled nut five full
turns and Presto! (sp?), it's busted.

Happy Birthday.
"Who can trust a people who celebrate, as their national event, a
jailbreak?" - M. Thatcher


-------------------------------
John Dacey
Business Cycles, Miami, Florida
Since 1983
Comprehensive catalogue of track equipment: online since 1996.
http://www.businesscycles.com

Leo Lichtman wrote:
wrote: (clip) I can't even figure out what
force per distance might be.
^^^^^^^^^^^^^^^^
Suppose you set up a lever, which presses upward on a load at some arbitrary
fixed distance from the fulcrum. Now, press down on the lever to create a
lifting force on the load. The amount of lifting force will be proportional
to the distance from the fulcrum, so you have tons/furlong. What could be
more obvious? :-)

I know you've got the smiley, but:

Since the torque is directly proportional, it'd be ton·furlong. If the
relationship had been inversely proportional, then it'd be ton/furlong.

I'm course, you probably knew that and I'm probably an ass...but who's
counting?


--
Paul M. Hobson
Georgia Institute of Technology
http://www.underthecouch.org
..:you may want to fix my email
address before you send anything:.