Potential good news for Mt. Washington access.

Discussion in 'Road Cycling' started by Wayne Pein, Dec 30, 2004.

  1. Wayne Pein

    Wayne Pein Guest

    Tags:


  2. 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]
     
  3. 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
     
  4. Mike Schwab

    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.
     
  5. -----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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  6. Matt O'Toole

    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.
     
  7. -----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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  8. Mike Kruger

    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
     
  9. Matt O'Toole

    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.
     
  10. 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]
     
  11. Matt O'Toole

    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]
     
  12. Matt O'Toole

    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.
     
  13. 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 pissed off at the
    bicyclist, not the car driver.

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

    Jobst Brandt
    [email protected]
     
  14. Matt O'Toole

    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 pissed 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.
     
  15. Mike DeMicco

    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]>
     
  16. 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]
     
  17. Matt O'Toole

    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.
     
  18. 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]
     
  19. [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]
     
  20. 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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