Heat resistant tubular glue?



[email protected] wrote:

> Anyone feel like having a go on calculating how much heat is generated
> by riders of various weights braking from various speeds?


A hard stop from high speed on a fast mountain descent: 600 degrees F.

(A friend of mine who used to work at a sensor mfg business measured it
with a thermocouple in the brake pad.)
 
Qui si parla Campagnolo aka Peter Chisholm wrote:
> ...
> I have not had a pinch flat when riding tubulars for 2 decades....


Those are some durable tires, if they last two (2) decades! ;)

--
Tom Sherman - Fox River Valley
 
Michael Press writes:

>> In the absence of a thermometer, said sizzle does not provide
>> evidence of a temperature beyond 100o,


> Yes, it does. Sizzling sound is incontrovertible proof that the
> liquid water is in contact with material at a temperature above the
> water's boiling point. That the water starts as freezing water or
> frozen water strongly suggests that the rim is well above 100 C.


Well, it wasn't frozen inside the rim. That was icy creek water and
snow melt but it got warmed up to hot water in a hurry when braking
before hirpin turns.

> Stelvio Pass ~ 2757 m. Boiling point of water: 90 C.
> 1500 m. ----------------------- 95 C.


The word sizzling was introduced by Mr. anonymous who goes on about
this below. I reported steam escaping from the rim around the valve
stem with a hissing blast that sounded like a major hole in the tire
during repeated braking for hairpin turns. That it was steam escaping
and not a tire leak was determined by stopping on a straight section
with the same result that quickly ceased as soon as the bicycle came
to rest.

>> ... and probably not even that, since your Alpine adventures
>> presumably involved considerable altitude. (Note that I did not
>> say anything about "steam".)


I didn't miss that. The implication is that I don't recognize steam
when I see and hear it.

Jobst Brandt
 
[email protected] writes:

>> Anyone feel like having a go on calculating how much heat is
>> generated by riders of various weights braking from various speeds?


> A hard stop from high speed on a fast mountain descent: 600 degrees F.


> (A friend of mine who used to work at a sensor mfg business measured
> it with a thermocouple in the brake pad.)


That doesn't clarify the matter because the face of brake material,
the medium in which heat is generated, is a concentration of energy
that must escape into the rim do dissipate. I discovered that with my
first experiments with wooden rims that, although they solved my
tubular tire creep problem, they ate up brake pads at a high rate as
they melted and burned off... not to mention hot debris hitting my
legs.

Brake pads are insulators besides being friction material, so almost
no heat is dissipated from the bad to the surroundings. You may
recall Mathauser brake pads mounted on cooling fins that had no
benefit because practically all pad heat must go into the rim. For
this reason hard anodized and ceramic coated brake surfaces on rims
have noticeably bad braking characteristics. If they didn't, all more
expensive rims would have such coatings on the brake track to prevent
wear.

Jobst Brandt
 
"Mike Krueger" <[email protected]> wrote in message
news:[email protected]...
> [email protected] wrote:
>
>> Argh! I almost ordered some rims with fantasies of riding Clement
>> Paris-Roubaix's... Does your friend have a "normal" retail price for
>> random joes like me?
>>
>> Regular CX is no problem for me to find, and I can get unlimited Pave
>> EVO's for $65. But that ugly green tread makes me nauseous!
>>
>> Do you know of anyone who has tried the Schwalbe Stelvio 700x25
>> tubulars?

>
> The USA importer is a friend of a friend. This does not enable me to
> get tires for you or anyone else, unfortunately.
> We did contact him today regarding the availability of Clement
> tubulars. We were told that Clement brand is owned by Pirelli Tire
> Company and it was licensed by Vittoria Tires. Vittoria stopped selling
> Clement in the USA, so Clement tubulars will no longer be available
> here. However, his company is still importing DEDA, Hutchinson, and
> Challenge tubulars. Challenge is the son of the founder of Clement. All
> of the tires are made in Bangkok, as are the Vittorias. I'm pretty sure
> that Hutchinson and Challenge both offer tubulars in wide widths.
> Also, Veloflex, which is still handmade in Italy, offers the Roubaix
> 700x24c tubular, and Continental now produces their top-of-the-line
> Competition tubular in 700x25c width. Danny at [email protected] can get
> both of these for you if you are interested.
> I don't have any personal experience with Schwalbe tires.
>

I thought the cyclo cross riders used tubulars ? are these wider and would
they be suitable for the road.
PK
 
On 05 Jan 2006 03:54:39 GMT, [email protected] wrote:

> introduced by Mr. anonymous


Could you please refer to other posters by the names they refer to
themselves by -- it will keep long threads clearer. If you want to
criticize their using a screen name, please do so explicity, rather
than doing so in a way that makes who said what even more obscure.

Thanks,

JT

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On Thu, 5 Jan 2006 07:23:22 -0000, "PK" <[email protected]>
wrote:

>[ cyclo cross tubulars] are these wider


Generally yes.

> and would
>they be suitable for the road.


Generally no, due to their large tread patterns.

JT


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On Thu, 05 Jan 2006 07:53:25 -0500, John Forrest Tomlinson
<[email protected]> wrote:

>On Thu, 5 Jan 2006 07:23:22 -0000, "PK" <[email protected]>
>wrote:
>
>>[ cyclo cross tubulars] are these wider

>
>Generally yes.
>
>> and would
>>they be suitable for the road.

>
>Generally no, due to their large tread patterns.


Cross treads vary from knobs to file patterns with some combining both elements.
The less aggressive patterns intended for non-muddy courses and grass work fine
on road. The only downside is that they are a softer compound and will wear
pretty fast. Also not much of a problem for road riding.

Ron
 
Michael Press wrote:
> In article
> <[email protected]>,
> [email protected] wrote:
>
> > In the absence of a thermometer, said sizzle does not provide evidence
> > of a temperature beyond 100o,

>
> Yes, it does. Sizzling sound is incontorvertible proof
> that the liquid water is in contact with material at a
> temperature above the water's boiling point. That the
> water starts as freezing water or frozen water strongly
> suggests that the rim is well above 100 C.
>
> Stelvio Pass ~ 2757 m. Boiling point of water: 90 C.
> 1500 m. ----------------------- 95 C.


No it doesn't. Since we don't know the altitude, we don't know what the
boiling point of water is. Furthermore, I said *beyond* 100o. It may
suggest "well above 100 C" to you, but to me it only suggests whatever
the boiling point was at that altitude. Back to my original point-
Brandt is taking an unscientific observation and trying to suggest it
is more than that. You want to prove the temperature was above 100o,
then get a damn thermometer.

Although I seem to remember Brandt talking about the snow frying on the
rim, I'll take his word for it instead of looking it up. "Seeing" steam
does not even require boiling, or anything close to boiling; for that
you only need water evaporating from a warm surface into cold air- the
water vapor condenses as it cools quickly in the cold air and becomes
visible as what most people refer to as "steam". Raising the
temperature of water suddenly from 0oC to, say, 60oC in an enclosed
space would also raise pressure as some of it evaporates, so it *might*
cause hissing. Like I said, get a thermometer.
 
[email protected] wrote:
> [email protected] wrote:
>
> > Anyone feel like having a go on calculating how much heat is generated
> > by riders of various weights braking from various speeds?

>
> A hard stop from high speed on a fast mountain descent: 600 degrees F.
>
> (A friend of mine who used to work at a sensor mfg business measured it
> with a thermocouple in the brake pad.)


That's the pad temperature, not the same as rim temperature. A rim
heated to 600oF would pretty much blow up any tire, clincher or
tubular.
 
discount auto here in swfla has 3-4 types of permatex double barrell
epoxy on the gooo rack
i'm using the walmart devcon variety for walsneaker reglue-rubber? to
rubber?
the waldevcon is a winner
the permatex 30 munute cure with clamps or no minute cure if no clamps
should glue your butt to the ceiling
 
[email protected] wrote:
> [email protected] wrote:
>
> > Anyone feel like having a go on calculating how much heat is generated
> > by riders of various weights braking from various speeds?

>
> A hard stop from high speed on a fast mountain descent: 600 degrees F.
>
> (A friend of mine who used to work at a sensor mfg business measured it
> with a thermocouple in the brake pad.)


Wow. The *only* measured number in this whole thread and it gets
dismissed in every reply.
 
[email protected] wrote:
> ...
> the permatex 30 munute cure with clamps or no minute cure if no clamps
> should glue your butt to the ceiling


Speaking from experience Gene? ;)

--
Tom Sherman - Fox River Valley
 
Peter Chisholm wrote:

> I like Sheldon and appreciate his inputs and knowledge but like Jobst,
> he does not now nor has used tubulars for a long time. Does not sell
> them in the store he calls home so-


I like you too, Peter, and also appreciate your stuff, but there's a bit
of a logical fallacy here, it seems to me.

I don't now and haven't for a long time used LSD either, and I don't
sell it at the store so-

Does that mean that if I advise others against using LSD my credibility
is less than that of a current LSD user? ;-)

Sheldon "Actually Does Still Occasionally Ride Tubulars, Two Of My Bikes
Are Equipped With Them" Brown
+---------------------------------------------------------+
| There are several good protections against temptation, |
| but the surest is cowardice. --Mark Twain |
+---------------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com
 
Sheldon Brown wrote:
> Peter Chisholm wrote:
>
>> I like Sheldon and appreciate his inputs and knowledge but like Jobst,
>> he does not now nor has used tubulars for a long time. Does not sell
>> them in the store he calls home so-

>
>
> I like you too, Peter, and also appreciate your stuff, but there's a bit
> of a logical fallacy here, it seems to me.
>
> I don't now and haven't for a long time used LSD either, and I don't
> sell it at the store so-
>
> Does that mean that if I advise others against using LSD my credibility
> is less than that of a current LSD user? ;-)


It sure is, if the stuff has changed since the days when you were
dropping it. Hmmm - there must be somebody following this NG who can
give us info on the quality of today's LSD contra that which was
available, say, 30 years ago?

/Robert "It's déjà vu all over again" Brown
 
Joseph Santaniello wrote:
> My WAG on how much the rims cools before the next hairpin is 20C. This
> gives the light rider's rims time to recover, but eventually the temp
> will get very high. The heavy rider never has time to recover, and very
> quickly is up at extreme temps. The heavy riders higher braking forces
> also make any "give" in the glue more apparent, as the tire creeps
> around the rim.
>
> I'm gonna buy clinchers. Only because of this heat issue. I like the
> ride of tubulars, I have a pet theory that larger riders notice the
> better ride more than others, and I don't see the glue as a hassle, nor
> the patching process. But I intend to go to Mallorca this spring, and
> maybe Italy in the summer, and there will plenty opportunity for me to
> melt glue there!


Your example represents some pretty extreme riding- putting out 250-300
watts down an 8% grade, braking extremely hard for the last 3 seconds
before coasting through a hairpin hard over, and then immediately
transitioning back to near full throttle. If you ride like this and are
predicting a heat buildup, I recommend a front disc brake.

It is easy to plug some parameters to an equation that result in
virtual glue melting. I don't think many people could match this
scenario in real life.
 
[email protected] wrote:
> Joseph Santaniello wrote:
> > My WAG on how much the rims cools before the next hairpin is 20C. This
> > gives the light rider's rims time to recover, but eventually the temp
> > will get very high. The heavy rider never has time to recover, and very
> > quickly is up at extreme temps. The heavy riders higher braking forces
> > also make any "give" in the glue more apparent, as the tire creeps
> > around the rim.
> >
> > I'm gonna buy clinchers. Only because of this heat issue. I like the
> > ride of tubulars, I have a pet theory that larger riders notice the
> > better ride more than others, and I don't see the glue as a hassle, nor
> > the patching process. But I intend to go to Mallorca this spring, and
> > maybe Italy in the summer, and there will plenty opportunity for me to
> > melt glue there!

>
> Your example represents some pretty extreme riding- putting out 250-300
> watts down an 8% grade, braking extremely hard for the last 3 seconds
> before coasting through a hairpin hard over, and then immediately
> transitioning back to near full throttle. If you ride like this and are
> predicting a heat buildup, I recommend a front disc brake.
>
> It is easy to plug some parameters to an equation that result in
> virtual glue melting. I don't think many people could match this
> scenario in real life.


There may not be many people who match this scenario, but I do, and
that is who I am buying wheels for :)

This is for some people an extreme condition, but I think for anyone
who is over say 90kg who rides regularly on old, steep mountain roads
it is not that uncommon. Newer roads as found often in the USA do not
have the drastic grade, nor as sharp turns as is found in the Alps, and
Northern Italy, etc. Of course there are plenty of very extreme
descents in the US, but they are hardly the norm, as such descents are
in Europe.

The bit about pumping out 300W and the jamming on the brakes such that
one nearly endos is extreme, but even just coasting the buildup
differences are quite a bit between light and heavy riders. I encourage
anyone interested to fill up a backpack with 30kg of rocks and wear it
down any halfway steep descent. (Wear it up the climb too!) Just the
force with which one would need to sqeeze the brakes would demonstrate
just how much more braking action a heavy rider does.

The disc brake comment is interesting, because when I first tried disc
brakes on my MTB I was running around telling everyone that I thought
they were the greatest thing since sliced bread. The braking forces
that can be generated without feeling like the cable is about to snap
made riding much more comfortable for me. But most people weren't that
interested. Several of my riding buddies even went back to non-disc
brakes. Their weight and riding just don't warrant the braking power
that mine does.

I think the Templistik experiment would be fun.

joseph
 
[email protected] wrote:
> [email protected] wrote:
> > Your example represents some pretty extreme riding- putting out 250-300
> > watts down an 8% grade, braking extremely hard for the last 3 seconds
> > before coasting through a hairpin hard over, and then immediately
> > transitioning back to near full throttle. If you ride like this and are
> > predicting a heat buildup, I recommend a front disc brake.
> >
> > It is easy to plug some parameters to an equation that result in
> > virtual glue melting. I don't think many people could match this
> > scenario in real life.

>
> There may not be many people who match this scenario, but I do, and
> that is who I am buying wheels for :)


I don't think you do. I am referring to the last scenario with the full
acceleration between curves and hard, last second braking.

> The bit about pumping out 300W and the jamming on the brakes such that
> one nearly endos is extreme, but even just coasting the buildup
> differences are quite a bit between light and heavy riders.


The difference is critical. In the coasting example the calculations
seem to show the heat buildup even at your weight does not seem to be
sufficient to melt glue, and the extreme example seems to barely exceed
the tested limits of the Vittoria glue (and might still provide an
adequate bond).

> The disc brake comment is interesting, because when I first tried disc
> brakes on my MTB I was running around telling everyone that I thought
> they were the greatest thing since sliced bread. The braking forces
> that can be generated without feeling like the cable is about to snap
> made riding much more comfortable for me. But most people weren't that
> interested. Several of my riding buddies even went back to non-disc
> brakes. Their weight and riding just don't warrant the braking power
> that mine does.


I think that if your riding style is extreme enough to worry about
melting glue, it is also extreme enough to worry about blowing tires,
especially if you are using clinchers, which require a somewhat higher
starting pressure than tubulars, in addition to the higher pressure
necessary to offset your weight. I believe that Brandt admits to
blowing off clinchers with his riding. I have read here that disc
brakes are becoming increasingly common on European roadbikes. They
certainly seem like the answer to your particular problem, uncoupling
braking from the tire decision. Then you would only have to worry about
the disc brake tearing the wheel out of the dropout, but that's a
problem for another thread.
 
[email protected] wrote:
> [email protected] wrote:
> > [email protected] wrote:
> > > Your example represents some pretty extreme riding- putting out 250-300
> > > watts down an 8% grade, braking extremely hard for the last 3 seconds
> > > before coasting through a hairpin hard over, and then immediately
> > > transitioning back to near full throttle. If you ride like this and are
> > > predicting a heat buildup, I recommend a front disc brake.
> > >
> > > It is easy to plug some parameters to an equation that result in
> > > virtual glue melting. I don't think many people could match this
> > > scenario in real life.

> >
> > There may not be many people who match this scenario, but I do, and
> > that is who I am buying wheels for :)

>
> I don't think you do. I am referring to the last scenario with the full
> acceleration between curves and hard, last second braking.


The first coasting only example didn't take into account brake bias.
Even changing the brake bias to a modest 80% the coasting example
generates quite a bit heat.

> > The bit about pumping out 300W and the jamming on the brakes such that
> > one nearly endos is extreme, but even just coasting the buildup
> > differences are quite a bit between light and heavy riders.

>
> The difference is critical. In the coasting example the calculations
> seem to show the heat buildup even at your weight does not seem to be
> sufficient to melt glue, and the extreme example seems to barely exceed
> the tested limits of the Vittoria glue (and might still provide an
> adequate bond).


The heat build-up from one hard brake application isn't enough, but 2-3
may be, depending upon the big unanswered question, how quickly do rims
and glue cool. Maybe it's 10-12 hard brake applications, who knows. But
it is certainly within the realm of normal behavior for heavy riders in
steep mountain terrain.

> > The disc brake comment is interesting, because when I first tried disc
> > brakes on my MTB I was running around telling everyone that I thought
> > they were the greatest thing since sliced bread. The braking forces
> > that can be generated without feeling like the cable is about to snap
> > made riding much more comfortable for me. But most people weren't that
> > interested. Several of my riding buddies even went back to non-disc
> > brakes. Their weight and riding just don't warrant the braking power
> > that mine does.

>
> I think that if your riding style is extreme enough to worry about
> melting glue, it is also extreme enough to worry about blowing tires,
> especially if you are using clinchers, which require a somewhat higher
> starting pressure than tubulars, in addition to the higher pressure
> necessary to offset your weight. I believe that Brandt admits to
> blowing off clinchers with his riding. I have read here that disc
> brakes are becoming increasingly common on European roadbikes. They
> certainly seem like the answer to your particular problem, uncoupling
> braking from the tire decision. Then you would only have to worry about
> the disc brake tearing the wheel out of the dropout, but that's a
> problem for another thread.


I don't actually ride in mountains that often, but for the few times I
do, I don't want to have to worry about the wheels. But the issue of
blowing a clincher from high heat isn't someting I'd thought about. But
actually that would be worse. It would just happen out of the blue,
while glue-melt happens gradually, and after one has had one
valve-shear blowout, one knows the danger signs and should have no
problem avoiding it again, at the expense of stopping often to switch
the wheel around.

I don't have anything to back this up, but I suspect that temperatures
must be much higher to blow clinchers off the rim than to melt glue.
But this is something I will certainly think about before I think I am
home free with clinchers.

In normal riding my braking acceleration isn't anywhere near as hard as
these examples, but the heating is the same for changing speeds
(discounting cooling effects while actually braking) and even around
here where it is only rolling hills, I hardly ever have a day where I
don't go 60+ at least once, so those few days in the mountains will
certainly see so higher speeds than that. If I tried to routinely brake
with 97% weight transfer, I think my helmet would get a good work-out!
I do ride front-brake endos on my MTB to entertain my 6 year old son...

Joseph
 
Joseph Santaniello writes:

>>>> Your example represents some pretty extreme riding- putting out
>>>> 250-300 watts down an 8% grade, braking extremely hard for the
>>>> last 3 seconds before coasting through a hairpin hard over, and
>>>> then immediately transitioning back to near full throttle. If
>>>> you ride like this and are predicting a heat buildup, I recommend
>>>> a front disc brake.


>>>> It is easy to plug some parameters to an equation that result in
>>>> virtual glue melting. I don't think many people could match this
>>>> scenario in real life.


>>> There may not be many people who match this scenario, but I do,
>>> and that is who I am buying wheels for :)


>> I don't think you do. I am referring to the last scenario with the
>> full acceleration between curves and hard, last second braking.


> The first coasting only example didn't take into account brake bias.
> Even changing the brake bias to a modest 80% the coasting example
> generates quite a bit heat.


Forget about the pedaling between braking. It doesn't amount to any
significant heating. To put this in perspective, see how hot you can
make your rim doing this on flat terrain. You can't make any
significant temperature that way. Besides, all the riders around here
had tubular glue problems on even paved descents around here.
Stopping to turn the front wheel around was a common method.

>>> The bit about pumping out 300W and the jamming on the brakes such
>>> that one nearly endos is extreme, but even just coasting the
>>> buildup differences are quite a bit between light and heavy
>>> riders.


>> The difference is critical. In the coasting example the
>> calculations seem to show the heat buildup even at your weight does
>> not seem to be sufficient to melt glue, and the extreme example
>> seems to barely exceed the tested limits of the Vittoria glue (and
>> might still provide an adequate bond).


> The heat build-up from one hard brake application isn't enough, but
> 2-3 may be, depending upon the big unanswered question, how quickly
> do rims and glue cool. Maybe it's 10-12 hard brake applications,
> who knows. But it is certainly within the realm of normal behavior
> for heavy riders in steep mountain terrain.


This is all misapplied calculations. I don't think the participants
in this thread have ever had a tubular tire experience with hot rims.
This was a serious problem in the days of tubulars.

>>> The disc brake comment is interesting, because when I first tried
>>> disc brakes on my MTB I was running around telling everyone that I
>>> thought they were the greatest thing since sliced bread. The
>>> braking forces that can be generated without feeling like the
>>> cable is about to snap made riding much more comfortable for me.
>>> But most people weren't that interested. Several of my riding
>>> buddies even went back to non-disc brakes. Their weight and
>>> riding just don't warrant the braking power that mine does.


>> I think that if your riding style is extreme enough to worry about
>> melting glue, it is also extreme enough to worry about blowing
>> tires, especially if you are using clinchers, which require a
>> somewhat higher starting pressure than tubulars, in addition to the
>> higher pressure necessary to offset your weight. I believe that
>> Brandt admits to blowing off clinchers with his riding. I have
>> read here that disc brakes are becoming increasingly common on
>> European road bikes. They certainly seem like the answer to your
>> particular problem, uncoupling braking from the tire decision.
>> Then you would only have to worry about the disc brake tearing the
>> wheel out of the dropout, but that's a problem for another thread.


Put the blame on "riding style" aka, you don't know how to ride. I'm
used to hearing that about all sorts of mechanical failures when in
fact it means that you are riding where I don't believe on reasonably
should. Given a slope and a maximum speed on a descent, the heat must
be generated. My last clincher blow-off occurred when I waited for a
friend who stopped to take pictures on a descent while I slowly oozed
along riding one brake at no more than 10mph.

> I don't actually ride in mountains that often, but for the few times
> I do, I don't want to have to worry about the wheels. But the issue
> of blowing a clincher from high heat isn't something I'd thought
> about. But actually that would be worse. It would just happen out
> of the blue, while glue-melt happens gradually, and after one has
> had one valve-shear blowout, one knows the danger signs and should
> have no problem avoiding it again, at the expense of stopping often
> to switch the wheel around.


Well that isn't a big problem if you let a little air out, but with
tubulars, inflation pressure is not the issue but rather rim
temperature. The reason the pressure doesn't present a problem for
tubulars is that the tube is insulated from the rim by a base tape,
stitching, selvage, and chafing cloth over the stitching, so little of
the brake heat enters inflation air. Besides, tire creep for tubulars
on the rim is inflation pressure independent.

> I don't have anything to back this up, but I suspect that
> temperatures must be much higher to blow clinchers off the rim than
> to melt glue. But this is something I will certainly think about
> before I think I am home free with clinchers.


You can say that with grate assurance. We don't blow tires off rims
but rarely, but creeping tubulars and subsequent stem failures were
relatively common. I would not have spent time installing insulator
strips on my tubular rims otherwise. These were entirely effective
and also protected the tubular base tape from rim chafing.

> In normal riding my braking acceleration isn't anywhere near as hard
> as these examples, but the heating is the same for changing speeds
> (discounting cooling effects while actually braking) and even around
> here where it is only rolling hills, I hardly ever have a day where
> I don't go 60+ at least once, so those few days in the mountains
> will certainly see so higher speeds than that. If I tried to
> routinely brake with 97% weight transfer, I think my helmet would
> get a good work-out! I do ride front-brake endos on my MTB to
> entertain my 6 year old son...


Don't worry about how hard you brake, the energy is dissipated into the
rim at any rate and the energy will go into the rim.

Jobst Brandt