Potential good news for Mt. Washington access.



Wayne Pein writes:

> It appears that cyclists may have a good case in gaining access to
> Mt. Washington in New Hampshire.


> http://www.velonews.com/news/fea/7346.0.html


That's an interesting case considering that it is a steep road. I
don't know whether there have been any injuries from crashing
bicyclists here but in the Alps, especially in Austria, where there
are exceptionally steep mountain roads, bicycles are prohibited
downhill to prevent blowouts from overheating rims.

Zirlerberg Pass has six runaway tracks for failed automotive brakes
like this one. Bicycles are prohibited down this road but not up.

http://tinyurl.com/jhiu

However, the road is famous for bicycling just the same with a hill
climb similar to the old auto races except a lot slower. See bottom
of this page:

http://www.kolumbus.fi/leif.snellman/hca6.htm

There have been several fatal crashes of bicyclists Locally on steep
descents in which the cause was attributed to excess speed and failure
to negotiate a curve. I have not seen the bicycles involved but am
fairly sure that these were tire blow-offs, something that is easily
proven by whether the bead of the rim was on the pavement before the
crash. In the Alps, road authorities have have banned downhill
bicycling on various steep descents for this reason.

Jobst Brandt
[email protected]
 
C

Charles Beristain

Guest
On Thu, 30 Dec 2004 20:01:25 GMT, [email protected]
wrote:

>Wayne Pein writes:
>
>> It appears that cyclists may have a good case in gaining access to
>> Mt. Washington in New Hampshire.


It would be very dangerous to ride down MW .. especially when cars are
also going up and down.

I think what really sticks in our craws is that it costs $300 to be
allowed to ride up MW and that happens only once per year (with one
practice day.. but even then, the car that brings you down has to pay
to go up). Only 600 riders each year.

charlieb in ct
 
M

Mike Schwab

Guest
Charles Beristain wrote:

> On Thu, 30 Dec 2004 20:01:25 GMT, [email protected]
> wrote:
>
>
>>Wayne Pein writes:
>>
>>
>>>It appears that cyclists may have a good case in gaining access to
>>>Mt. Washington in New Hampshire.

>
>
> It would be very dangerous to ride down MW .. especially when cars are
> also going up and down.
>
> I think what really sticks in our craws is that it costs $300 to be
> allowed to ride up MW and that happens only once per year (with one
> practice day.. but even then, the car that brings you down has to pay
> to go up). Only 600 riders each year.
>
> charlieb in ct


On Maui, there is a race to the top of the volcano, 38 miles 10,000 ft.
There are also tour companies that haul you and their bicycle to the
top for sunrise then follow you downhill. They can only use disk brakes
on their bicycles.
 
B

Booker C. Bense

Guest
-----BEGIN PGP SIGNED MESSAGE-----

In article <[email protected]>,
<[email protected]> wrote:
>Wayne Pein writes:
>
>> It appears that cyclists may have a good case in gaining access to
>> Mt. Washington in New Hampshire.

>
>> http://www.velonews.com/news/fea/7346.0.html

>
>That's an interesting case considering that it is a steep road. I
>don't know whether there have been any injuries from crashing
>bicyclists here but in the Alps, especially in Austria, where there
>are exceptionally steep mountain roads, bicycles are prohibited
>downhill to prevent blowouts from overheating rims.


_ Actually, it's not THAT steep, except for a few hundred yards
at the very top. It's just incredibly sustained, 12% for 7+ miles[1]
most of which is hard packed dirt. If you plot dist vs elevation
you get a nearly straight line. I've both ridden up and run up it
and in my experience riding up it is harder.

_ It's not allowed to ride down it and it's only allowed to ride up
it twice a year as part of an anuual race that has a lottery for
entries and a very high entry fee. Descending it on skinny tires
would be very unpleasant, it would be a blast with fat tires if
you didn't have to worry about cars wandering all over the road
with driver's watching the scenery. I think you'd have a hard
time fighting "rational basis" ban on cyclists.

_ Booker C. Bense

[1]- okay, okay 12% is steep, but I'll take a mile of 12% over
a quarter mile of 20% any day.

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Matt O'Toole

Guest
Booker C. Bense wrote:

> _ Actually, it's not THAT steep, except for a few hundred yards
> at the very top. It's just incredibly sustained, 12% for 7+ miles[1]
> most of which is hard packed dirt. If you plot dist vs elevation
> you get a nearly straight line. I've both ridden up and run up it
> and in my experience riding up it is harder.
>
> _ It's not allowed to ride down it and it's only allowed to ride up
> it twice a year as part of an anuual race that has a lottery for
> entries and a very high entry fee. Descending it on skinny tires
> would be very unpleasant, it would be a blast with fat tires if
> you didn't have to worry about cars wandering all over the road
> with driver's watching the scenery. I think you'd have a hard
> time fighting "rational basis" ban on cyclists.


Mountain bikers ride fire roads like that all the time. The mountains of the
western US are riddled with them -- 4000' climbs at over 10%, sometimes over
15%. Rims get hot, but not enough to blow tires. So I don't see what the big
deal is. There are a bunch of roads around here with sustained grades like
that, but nothing that long -- 2-3 miles at most.

However, when you have such a road that's a magnet for cyclists, you have a
management problem. As mentioned, that particular road is privately owned, so
there may be liability concerns too. I say people ought to be free to crash if
they want to, but unfortunately US law and insurance doesn't work that way.

Matt O.
 
B

Booker C. Bense

Guest
-----BEGIN PGP SIGNED MESSAGE-----

In article <[email protected]>,
Matt O'Toole <[email protected]> wrote:
>Booker C. Bense wrote:
>
>> _ Actually, it's not THAT steep, except for a few hundred yards
>> at the very top. It's just incredibly sustained, 12% for 7+ miles[1]
>> most of which is hard packed dirt. If you plot dist vs elevation
>> you get a nearly straight line. I've both ridden up and run up it
>> and in my experience riding up it is harder.
>>
>> _ It's not allowed to ride down it and it's only allowed to ride up
>> it twice a year as part of an anuual race that has a lottery for
>> entries and a very high entry fee. Descending it on skinny tires
>> would be very unpleasant, it would be a blast with fat tires if
>> you didn't have to worry about cars wandering all over the road
>> with driver's watching the scenery. I think you'd have a hard
>> time fighting "rational basis" ban on cyclists.

>
>Mountain bikers ride fire roads like that all the time. The mountains of the
>western US are riddled with them -- 4000' climbs at over 10%, sometimes over
>15%. Rims get hot, but not enough to blow tires. So I don't see what the big
>deal is. There are a bunch of roads around here with sustained grades like
>that, but nothing that long -- 2-3 miles at most.


_ I agree, for a reasonably competent mountain biker that road
would be no big deal at all. There are many many fire roads out
west that are significantly steeper with much worse road
conditions.

>
>However, when you have such a road that's a magnet for cyclists, you have a
>management problem. As mentioned, that particular road is privately owned, so
>there may be liability concerns too. I say people ought to be free to crash if
>they want to, but unfortunately US law and insurance doesn't work that way.


_ There's also the fact that it is surrounded by a protected
wilderness area that is illegal for mountain biking. I'm guessing
it would be up to the Auto road company to cover the cost of
enforcing that and I think they could make a pretty reasonable
"rational basis" on just that arguement alone, outside of any
safety issues.

_ Booker C. Bense



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Mike Kruger

Guest
Matt O'Toole wrote:
>
> Mountain bikers ride fire roads like that all the time.

The
> mountains of the western US are riddled with them -- 4000'

climbs at
> over 10%, sometimes over 15%. Rims get hot, but not

enough to blow
> tires. So I don't see what the big deal is. There are a

bunch of
> roads around here with sustained grades like that, but

nothing that
> long -- 2-3 miles at most.
>

A couple of questions:
1. Wouldn't mountain bike tires take more heat, just because
of their greater mass and volume?
2. On a mountain bike on a fire road, wouldn't one still be
going more slowly than on a road bike on a paved road?
Both would seem to contribute to a mountain bike tire being
less likely to blow off the rim.
However, I will defer to the mechanical engineers among the
group.


--
Mike Kruger
Too many people spend money they haven't earned
to buy things they don't want
to impress people they don't like. -Will Rogers
 
M

Matt O'Toole

Guest
Mike Kruger wrote:

> 1. Wouldn't mountain bike tires take more heat, just because
> of their greater mass and volume?


Rim mass and area makes more difference in dissipating heat than rubber and air
(which are not good conductors). However, most mountain bike rims are not too
different from road bike rims in this respect. The important factors are a
mountain bike tire's lower pressure, and maybe a fatter, more robust bead hook.

> 2. On a mountain bike on a fire road, wouldn't one still be
> going more slowly than on a road bike on a paved road?


The potential energy to be dissipated is the same either way. Though it's
counterintuitive, higher speeds actually produce lower rim temperatures, because
of increased airflow. The hottest my rims ever got was creeping down very steep
(>20%) grades.

Matt O.
 
Matt O'Toole writes:

> Mountain bikers ride fire roads like that all the time. The
> mountains of the western US are riddled with them -- 4000' climbs at
> over 10%, sometimes over 15%. Rims get hot, but not enough to blow
> tires. So I don't see what the big deal is. There are a bunch of
> roads around here with sustained grades like that, but nothing that
> long -- 2-3 miles at most.


I'm unclear on what you are proposing. Do you mean that tires do not
blow off rims from brake heating? As a counterpoint, I have had two
of these occurrences and have witnessed many more. Beyond that, most
tandems use hub brakes because tire bow-off is such a problem for
them, having more mass and less wind drag than single bicycles and
only two rims for two people.

> However, when you have such a road that's a magnet for cyclists, you
> have a management problem. As mentioned, that particular road is
> privately owned, so there may be liability concerns too. I say
> people ought to be free to crash if they want to, but unfortunately
> US law and insurance doesn't work that way.


I think the management doesn't want the contention for road space
between bicycles and cars. I am aware of these problems locally
because there are a great many drivers who will not pass a bicyclist
climbing a grade on a curvy road even if the bicyclists rides outside
of the edge stripe on a paves highway. On an unpaved road this could
case traffic jams even with light auto traffic.

Jobst Brandt
[email protected]
 
M

Matt O'Toole

Guest
<[email protected]> wrote in message
news:[email protected]
> Matt O'Toole writes:
>
> > Mountain bikers ride fire roads like that all the time. The
> > mountains of the western US are riddled with them -- 4000' climbs at
> > over 10%, sometimes over 15%. Rims get hot, but not enough to blow
> > tires. So I don't see what the big deal is. There are a bunch of
> > roads around here with sustained grades like that, but nothing that
> > long -- 2-3 miles at most.

>
> I'm unclear on what you are proposing. Do you mean that tires do not
> blow off rims from brake heating? As a counterpoint, I have had two
> of these occurrences and have witnessed many more. Beyond that, most
> tandems use hub brakes because tire bow-off is such a problem for
> them, having more mass and less wind drag than single bicycles and
> only two rims for two people.
>
> > However, when you have such a road that's a magnet for cyclists, you
> > have a management problem. As mentioned, that particular road is
> > privately owned, so there may be liability concerns too. I say
> > people ought to be free to crash if they want to, but unfortunately
> > US law and insurance doesn't work that way.

>
> I think the management doesn't want the contention for road space
> between bicycles and cars. I am aware of these problems locally
> because there are a great many drivers who will not pass a bicyclist
> climbing a grade on a curvy road even if the bicyclists rides outside
> of the edge stripe on a paves highway. On an unpaved road this could
> case traffic jams even with light auto traffic.
>
> Jobst Brandt
> [email protected]
 
M

Matt O'Toole

Guest
[email protected] wrote:

> Matt O'Toole writes:
>
>> Mountain bikers ride fire roads like that all the time. The
>> mountains of the western US are riddled with them -- 4000' climbs at
>> over 10%, sometimes over 15%. Rims get hot, but not enough to blow
>> tires. So I don't see what the big deal is. There are a bunch of
>> roads around here with sustained grades like that, but nothing that
>> long -- 2-3 miles at most.

>
> I'm unclear on what you are proposing. Do you mean that tires do not
> blow off rims from brake heating? As a counterpoint, I have had two
> of these occurrences and have witnessed many more.


Of course this happens. I've seen it too, but it's not common. I don't think
there are too many hills in the US where this is likely to be a problem, Mt.
Washington included. Like I said, I've ridden many hills of similar steepness
and length for many years, and never heard of anyone blowing tires off. The
Alps are another story, with 2-3 times the vertical relief of most mountain
ranges in the US. How big and how steep a drop does it take to blow a tire off
anyway?

> I think the management doesn't want the contention for road space
> between bicycles and cars. I am aware of these problems locally
> because there are a great many drivers who will not pass a bicyclist
> climbing a grade on a curvy road even if the bicyclists rides outside
> of the edge stripe on a paves highway. On an unpaved road this could
> case traffic jams even with light auto traffic.


You're right about contention for space. Actual traffic jams should be
addressed. But drivers who are just pissy because they can't put the pedal to
the metal should not be pandered to like big babies, at the expense of other
road users. Unfortunately most managers would not want to face the issue, and
would prefer it never arise. Thus the ban.

Matt O.
 
Matt O'Toole writes:

>>> Mountain bikers ride fire roads like that all the time. The
>>> mountains of the western US are riddled with them -- 4000' climbs
>>> at over 10%, sometimes over 15%. Rims get hot, but not enough to
>>> blow tires. So I don't see what the big deal is. There are a
>>> bunch of roads around here with sustained grades like that, but
>>> nothing that long -- 2-3 miles at most.


>> I'm unclear on what you are proposing. Do you mean that tires do
>> not blow off rims from brake heating? As a counterpoint, I have
>> had two of these occurrences and have witnessed many more.


> Of course this happens. I've seen it too, but it's not common. I
> don't think there are too many hills in the US where this is likely
> to be a problem, Mt. Washington included. Like I said, I've ridden
> many hills of similar steepness and length for many years, and never
> heard of anyone blowing tires off. The Alps are another story, with
> 2-3 times the vertical relief of most mountain ranges in the US.
> How big and how steep a drop does it take to blow a tire off anyway?


I think you don't understand the problem. A steep section of 200
yards is enough to blow off a tire if only one (typically the front
one) rim brake is used. I have done it and so have others. If only
one in a hundred riders has such a failure and suffered serious injury
or death, as it has on local roads, all hell would break loose.

You may have seen pictures from Sonora Pass in California with its 26%
warnings. It has a few longer runs of 18% but these are straight and
require no braking until the next turn. These turns are mostly not
extra steep and I know of no one who had a tire blow-off on this pass
that is equally steep on both sides. I can imagine that it has
occurred, but not in any of the rides I have seen. In contrast, I
have seldom exceeded 50mph on this road because it is intermittently
extra steep and it has many curves where all speed is lost.

In contrast, a 13% grade on the Fedaia Pass and a 15% section of the
Rombo pass guarantee 60mph. Neither of these roads is a major hazard
to descending although the Rombo has a bicycles prohibited sign on
ascent of the Italian side. The steep descent is on the Austrian
side. The cavalier attitude to this hazard is classic of the machismo
in the USA and therefore no one will assess the hazard it being non
existent in the minds of bicyclists.

>> I think the management doesn't want the contention for road space
>> between bicycles and cars. I am aware of these problems locally
>> because there are a great many drivers who will not pass a bicyclist
>> climbing a grade on a curvy road even if the bicyclists rides outside
>> of the edge stripe on a paves highway. On an unpaved road this could
>> case traffic jams even with light auto traffic.


> You're right about contention for space. Actual traffic jams should
> be addressed. But drivers who are just pissy because they can't put
> the pedal to the metal should not be pandered to like big babies, at
> the expense of other road users. Unfortunately most managers would
> not want to face the issue, and would prefer it never arise. Thus
> the ban.


They are only looking out for your safety... so goes the word. It's
hard to argue with that. You may not have noticed, but the people
backed up behind one of these bike watchers are ****** off at the
bicyclist, not the car driver.

http://draco.acs.uci.edu/rbfaq/FAQ/6.1.html

Jobst Brandt
[email protected]
 
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Matt O'Toole

Guest
[email protected] wrote:

> I think you don't understand the problem. A steep section of 200
> yards is enough to blow off a tire if only one (typically the front
> one) rim brake is used. I have done it and so have others. If only
> one in a hundred riders has such a failure and suffered serious injury
> or death, as it has on local roads, all hell would break loose.


OK, 200 yards of how steep? Then wouldn't many of the bigger hills in San
Francisco or Los Angeles cause problems, being over 25%, or even 30%, for 200
yards? Or does it require being fairly hot already, from miles of steep but not
extreme grades before?

I do understand the problem, but as I said it has not been my experience on
similar grades. Perhaps it's because I've ridden most of these hills on a
mountain bike, and mountain bike tires aren't as prone to blowing off. I
haven't ridden too many huge hills on a road bike. The Appalachians have plenty
of steep roads, but not on the same scale as the Alps or the Sierras. I have
rolled tubulars before and sheared off valve stems, but never blown a clincher
off. My experiences with tubulars had me thinking I was going to die someday,
if I didn't switch to clinchers.

> You may have seen pictures from Sonora Pass in California with its 26%
> warnings. It has a few longer runs of 18% but these are straight and
> require no braking until the next turn.


I have driven over this road but not ridden it. It is in fact much steeper for
a longer distance than most "big" hills in the US.

> These turns are mostly not
> extra steep and I know of no one who had a tire blow-off on this pass
> that is equally steep on both sides. I can imagine that it has
> occurred, but not in any of the rides I have seen. In contrast, I
> have seldom exceeded 50mph on this road because it is intermittently
> extra steep and it has many curves where all speed is lost.
>
> In contrast, a 13% grade on the Fedaia Pass and a 15% section of the
> Rombo pass guarantee 60mph. Neither of these roads is a major hazard
> to descending although the Rombo has a bicycles prohibited sign on
> ascent of the Italian side. The steep descent is on the Austrian
> side. The cavalier attitude to this hazard is classic of the machismo
> in the USA and therefore no one will assess the hazard it being non
> existent in the minds of bicyclists.


Don't steep highways in the US usually have the grade posted on a yellow caution
sign? Shouldn't that be enough?

> They are only looking out for your safety... so goes the word. It's
> hard to argue with that. You may not have noticed, but the people
> backed up behind one of these bike watchers are ****** off at the
> bicyclist, not the car driver.
>
> http://draco.acs.uci.edu/rbfaq/FAQ/6.1.html


I guess that's what management is all about sometimes -- taking a position
that's hard to argue with!

Matt O.
 
M

Mike DeMicco

Guest
[email protected] wrote in news:tgFDd.662$m31.7334
@typhoon.sonic.net:

> Matt O'Toole writes:
>
>> Mountain bikers ride fire roads like that all the time. The
>> mountains of the western US are riddled with them -- 4000' climbs at
>> over 10%, sometimes over 15%. Rims get hot, but not enough to blow
>> tires. So I don't see what the big deal is. There are a bunch of
>> roads around here with sustained grades like that, but nothing that
>> long -- 2-3 miles at most.

>
> I'm unclear on what you are proposing. Do you mean that tires do not
> blow off rims from brake heating? As a counterpoint, I have had two
> of these occurrences and have witnessed many more. Beyond that, most
> tandems use hub brakes because tire bow-off is such a problem for
> them, having more mass and less wind drag than single bicycles and
> only two rims for two people.


Wouldn't the low pressure (35-45 psi) in mountain bike tires prevent a
blow offs? I have gone down some long, super steep descents on the brakes
the whole way and have never had a blow off nor have I ever seen someone
else have one. Most new mountain bikes seem to come with disc brakes
anyway.

--
Mike DeMicco <[email protected]>
 
Mike DeMicco writes:

>>> Mountain bikers ride fire roads like that all the time. The
>>> mountains of the western US are riddled with them -- 4000' climbs
>>> at over 10%, sometimes over 15%. Rims get hot, but not enough to
>>> blow tires. So I don't see what the big deal is. There are a
>>> bunch of roads around here with sustained grades like that, but
>>> nothing that long -- 2-3 miles at most.


>> I'm unclear on what you are proposing. Do you mean that tires do
>> not blow off rims from brake heating? As a counterpoint, I have
>> had two of these occurrences and have witnessed many more. Beyond
>> that, most tandems use hub brakes because tire bow-off is such a
>> problem for them, having more mass and less wind drag than single
>> bicycles and only two rims for two people.


> Wouldn't the low pressure (35-45 psi) in mountain bike tires prevent
> a blow offs? I have gone down some long, super steep descents on
> the brakes the whole way and have never had a blow off nor have I
> ever seen someone else have one. Most new mountain bikes seem to
> come with disc brakes anyway.


This isn't about MTB's. It is primarily a road bicycle problem. It
takes the same pressure to blow a skinny tire off a rim as a fat one,
the interface being the inside width of the rim, on which inflation
pressure acts (between tire and rim). If your 2.5" MTB tire on a
narrow rim can withstand 140psi then you may be able to experience
blow-off. On the other hand, starting at 45psi, I doubt that you
could get enough pressure even if you have a wider rim.

Jobst Brandt
[email protected]
 
M

Matt O'Toole

Guest
[email protected] wrote:

> This isn't about MTB's. It is primarily a road bicycle problem. It
> takes the same pressure to blow a skinny tire off a rim as a fat one,
> the interface being the inside width of the rim, on which inflation
> pressure acts (between tire and rim). If your 2.5" MTB tire on a
> narrow rim can withstand 140psi then you may be able to experience
> blow-off. On the other hand, starting at 45psi, I doubt that you
> could get enough pressure even if you have a wider rim.


So perhaps a 25mm or 28mm tire at 90psi is safer than a 23mm one at 120psi?
Care to make an educated guess at what the threshold of safety is? Wouldn't it
be interesting to test this?

Matt O.
 
Matt O'Toole writes:

>> This isn't about MTB's. It is primarily a road bicycle problem.
>> It takes the same pressure to blow a skinny tire off a rim as a fat
>> one, the interface being the inside width of the rim, on which
>> inflation pressure acts (between tire and rim). If your 2.5" MTB
>> tire on a narrow rim can withstand 140psi then you may be able to
>> experience blow-off. On the other hand, starting at 45psi, I doubt
>> that you could get enough pressure even if you have a wider rim.


> So perhaps a 25mm or 28mm tire at 90psi is safer than a 23mm one at
> 120psi? Care to make an educated guess at what the threshold of
> safety is? Wouldn't it be interesting to test this?


Interesting that you mention that, because I am working on a test for
blow-off. I made a valve stem pressure sensor adapter that, when
installed, opens the Presta valve to an aneroid pressure sensor that
sends its readings to a data-logger (about the size of a deck of
cards) that also reads a thermocouple attached to the rim. The data
logger is tied to the inside of the wheel near the hub and has a USB
connector to download test data to a PC where it can be charted.

The plan is to descend Hicks Road near Los Gatos CA using only the
rear brake at about 15mph until the tire blows off. Since this is
essentially a straight run, there is no problem stopping with a flat
rear tire. Each such run will require a new tube and I think the
second run should make clear whether this is reasonably repeatable.
Of course I'll have to cool the rim down with water before running
again and pump the tire to the same pressure.

I will also test a 1950's French touring rim tape that was designed to
prevent tire blow-off but was never recognized as such, and was
therefore, unmarketable from the Cupertino Bike Shop of those days.
After having not ridden down Hicks Rd. since the days of my insulated
tubulars, I was concerned about this descent the last few times I
recently came down that hill and recall reading about a fatality in
2004 on that road... attributed to lack of rider skill.

Not to worry, the results will be announced. There is still a matter
of designing a small circuit board for the thermocouple. I hope to
see a product emerge from this.

Jobst Brandt
[email protected]
 
F

Frank Krygowski

Guest
[email protected] wrote:

> I am working on a test for
> blow-off. I made a valve stem pressure sensor adapter that, when
> installed, opens the Presta valve to an aneroid pressure sensor that
> sends its readings to a data-logger (about the size of a deck of
> cards) that also reads a thermocouple attached to the rim. The data
> logger is tied to the inside of the wheel near the hub and has a USB
> connector to download test data to a PC where it can be charted.

....
>
> Not to worry, the results will be announced.


Excellent!

When you do this, please compare with a static pressure test of the same
tire and rim at room temperature.


--
--------------------+
Frank Krygowski [To reply, remove rodent and vegetable dot com,
replace with cc.ysu dot edu]
 
Frank Krygowski writes:

>> I am working on a test for blow-off. I made a valve stem pressure
>> sensor adapter that, when installed, opens the Presta valve to an
>> aneroid pressure sensor that sends its readings to a data-logger
>> (about the size of a deck of cards) that also reads a thermocouple
>> attached to the rim. The data logger is tied to the inside of the
>> wheel near the hub and has a USB connector to download test data to
>> a PC where it can be charted.


>> Not to worry, the results will be announced.


> Excellent!


> When you do this, please compare with a static pressure test of the
> same tire and rim at room temperature.


What do you mean by this. Inflation pressure is inflation pressure
whether the wheel is rotating or not. Whether the pump gauge and
wheel sensor are alike will show up from the start. Tires will be
inflated to 100psi before the test. The sensor will track temperature
from initial to final versus time.

Jobst Brandt
[email protected]
 

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