Heat resistant tubular glue?
joseph.sa...@gmail.com
I am considering going back to tubulars, but one of the issues that was
most problematic for me using them in the past was the glue melting
during heavy braking. I weigh 95-100 kg so it doesn't take too much
breaking to get generate lots of heat, and the braking forces are high
too, so the tires slide around on the rim a lot. This is not good. I
used 3M Fast Tack for a while but it seemed to kill the base tapes. I
haven't had to use glue for many years now.
So what is the story with tubular glue these days? What suggestions do
folks have for solutions to the melting problem?
Joseph
jobst....@stanfordalumni.org
Nothing has changed. All pressure sensitive glues are thermally
affected. If they have low thermal sensitivity they also do not stick
well for mounting a spare tire because they are not sufficiently
pressure sensitive once cured.
Why do you want to go back to the tubular routine?
Jobst Brandt
joseph.sa...@gmail.com
One thing is I don't live in an area with big descents, so the melting
issue isn't really that big a problem, unless I take my bike on a
vaction someplace. Then it's a luxury problem!
The real reason is comfort given my weight and the rough roads. I like
low pressure but don't want pinch flats, so I need a large section
clincher tire. I have clearance problems with large section tires, and
there are not many nice tires available in 25 width. Tubulars seem to
me to be able to be run at a lower pressure for a given size without
the pinch flat issue. Thus I get comfort without the clearance problems
and I get a wider range of tires to choose from that are of a suitable
width.
Does that make sense? Do say 22-23 tubulars offer as much "shock
absorbtion" as a 24-25 clincher at approx the same pressure?
Joseph
jobst....@stanfordalumni.org
>>> I am considering going back to tubulars, but one of the issues
>>> that was most problematic for me using them in the past was the
>>> glue melting during heavy braking. I weigh 95-100 kg so it doesn't
>>> take too much breaking to get generate lots of heat, and the
>>> braking forces are high too, so the tires slide around on the rim
>>> a lot. This is not good. I used 3M Fast Tack for a while but it
>>> seemed to kill the base tapes. I haven't had to use glue for many
>>> years now.
>>> So what is the story with tubular glue these days? What
>>> suggestions do folks have for solutions to the melting problem?
>> Nothing has changed. All pressure sensitive glues are thermally
>> affected. If they have low thermal sensitivity they also do not
>> stick well for mounting a spare tire because they are not
>> sufficiently pressure sensitive once cured.
>> Why do you want to go back to the tubular routine?
> One thing is I don't live in an area with big descents, so the
> melting issue isn't really that big a problem, unless I take my bike
> on a vacation someplace. Then it's a luxury problem!
> The real reason is comfort given my weight and the rough roads. I
> like low pressure but don't want pinch flats, so I need a large
> section clincher tire. I have clearance problems with large section
> tires, and there are not many nice tires available in 25 width.
> Tubulars seem to me to be able to be run at a lower pressure for a
> given size without the pinch flat issue. Thus I get comfort without
> the clearance problems and I get a wider range of tires to choose
> from that are of a suitable width.
> Does that make sense? Do say 22-23 tubulars offer as much "shock
> absorption" as a 24-25 clincher at approx the same pressure?
I don't believe so. If your tires are bottoming on roads, then you
are close to damaging rims and getting pinch flats anyway. I think
you need a suspension bicycle if the roads are that bad. Running
small soft tires is not a reasonable solution as I see it. I suspect
you gained some weight since you last rode tubulars. They are not
significantly better at withstanding pinch flats. Besides, you could
do this by getting latex tubes for your clinchers.
Jobst Brandt
Werehatrack
>... [Tubulars] are not
>significantly better at withstanding pinch flats. Besides, you could
>do this by getting latex tubes for your clinchers.
With perhaps the caveat that they'll need reinflation more often due
to their greater porosity than most butyl tubes. Since running
underinflated contributes to pinch flats, I have always viewed this as
a solution with its own set of problems. (My small experience with
tubulars led me to the conclusion that they were more trouble than
they were worth. I suspect that I am not alone in this conclusion,
and that this is a major reason that the clincher design has come to
dominate the market, since the tubular predates it.)
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.
joseph.sa...@gmail.com
At present I do weigh about 5kg more than when I used tubulars. I don't
run tires with so low that I get pinch flats (knock on wood, I haven't
had a flat in the last 6,000 km!) but occasionaly I hit a pebble or
something that bottoms out the tire, particularly if I am using
anything narrower than ACTUAL 23mm. But to smooth out road vibration, I
like a lower pressure, which means I need a larger casing, so I don't
actually bottom out ove rcracks, etc.
It is hardly a scientific survey, but I just measured the width and
unloaded distance from rim to outside of the tire on 3 clincher
wheelsets, and one tubular. One clincher set was 22mm wide with a
"depth" of 20mm, another 23mm wide 21mm deep, and another 24mm wide and
22mm deep, while the tubulars were 22mm wide and 21mm deep. So it seems
the 22mm tubulars have at least as much vertical travel as a 24mm
clincher. There are of course all sorts of other things involved, too,
but a few mm may be all that is needed to not bottom out. And it could
be a case of glue build-up giving a false measurment, or who knows.
I am by no means convinced that tubulars will be suitable for me, but
these are the things I am taking into consideration.
Joseph
jobst....@stanfordalumni.org
> At present I do weigh about 5kg more than when I used tubulars. I
> don't run tires with so low that I get pinch flats (knock on wood, I
> haven't had a flat in the last 6,000 km!) but occasionally I hit a
> pebble or something that bottoms out the tire, particularly if I am
> using anything narrower than ACTUAL 23mm. But to smooth out road
> vibration, I like a lower pressure, which means I need a larger
> casing, so I don't actually bottom out over cracks, etc.
The way to measure a tire cross section is to measure its width since
bicycle tires are not belted radials and their casings have a true
circular cross section. Measuring height may have something to do
with compressive travel, it is not the way tire size is measured, that
being to difficult to determine unless you measure rim height off the
ground before and after inflation.
> It is hardly a scientific survey, but I just measured the width and
> unloaded distance from rim to outside of the tire on 3 sets of
> clincher wheels, and one tubular. One was 22mm wide with a "depth"
> of 20mm, another 23mm wide 21mm deep, and another 24mm wide and 22mm
> deep, while the tubulars were 22mm wide and 21mm deep. So it seems
> the 22mm tubulars have at least as much vertical travel as a 24mm
> clincher. There are of course all sorts of other things involved,
> too, but a few mm may be all that is needed to not bottom out. And
> it could be a case of glue build-up giving a false measurement, or
> who knows.
The difference you ar eseeing is probably tube+casing+tread thickness.
> I am by no means convinced that tubulars will be suitable for me, but
> these are the things I am taking into consideration.
I think the comment that tubulars are more trouble than they are worth
is appropriate. That is why they are hardly used these days although
they were the only tires before about the 1980's.
Jobst Brandt
Ted Bennett
> Joseph Santaniello writes:
> > I am by no means convinced that tubulars will be suitable for me, but
> > these are the things I am taking into consideration.
>
> I think the comment that tubulars are more trouble than they are worth
> is appropriate. That is why they are hardly used these days although
> they were the only tires before about the 1980's.
>
> Jobst Brandt
That comment will get the usual responses from others here, so here's
mine: the first really fine bicycle I purchased was in 1980. New
beaded tires were being introduced, and the claim was that they were
just as good as tubulars. I got tubulars. That's what all the good
bikes had, right? They were fine, and I didn't seem to get all that
many flats (still don't). But even infrequent flats are a nuisance that
is easier to deal with on a tire that isn't glued on.
These days all my bikes except one wear clinchers. I do like the feel
of the tubies, but the difference is so small and difficult to describe
or measure that I'm just not willing to tolerate the disadvantages.
Sheldon Brown sums it up well on http://sheldonbrown.com/tires.html :
"Tubulars are considerably more expensive than clinchers of comparable
performance.
Tubulars are very much harder to repair once punctured. Most people
just throw them away.
You need to carry a complete spare tubular in case you get a flat.
This negates the weight advantage over clinchers, unless you have a team
car following you with spare wheels.
If you replace a tubular on the road, you cannot corner safely at high
speeds until you go home and re-glue the tire. For safe high-speed
cornering, the glue needs to dry for at least several hours.
Tubulars have higher rolling resistance than the best clinchers.
Tubulars are rarely as true and round as clinchers.
Improperly glued tubulars can roll off the rim. This almost always
causes a serious crash."
--
Ted Bennett
Nick Payne
light, will just fit most racing frames (it fits with minimal clearances in
both the Klein and Litespeed road bikes that I have), and you could probably
run it at 85-90 psi and not pinch flat.
I've actually raced on the Roly Poly a couple of times, out of curiousity.
Couldn't really detect any difference in my performance vs other riders
compared to the Conti GP3000 that I normally used...
Nick
<joseph.sa...@gmail.com> wrote in message
news:1136133763.3...@g14g2000cwa.googlegroups.com...
joseph.sa...@gmail.com
Nick Payne wrote:
> Try the Panaracer Roll-y Pol-y 700x28 (a real 27mm on my rims). It is fairly
> light, will just fit most racing frames (it fits with minimal clearances in
> both the Klein and Litespeed road bikes that I have), and you could probably
> run it at 85-90 psi and not pinch flat.
>
> I've actually raced on the Roly Poly a couple of times, out of curiousity.
> Couldn't really detect any difference in my performance vs other riders
> compared to the Conti GP3000 that I normally used...
>
> Nick
I have used Michelin Pro Race2 700x25 (actual 27-28 on my rims) and
they have been my favorite tire. They have a few mm of clearance, but
when I ride, the wheels flex enough that they rub. Both side to side
when I stand, and up and down when I go over a bump, or more often when
I ride through a small dip.
I haven't found a nice true 25 yet.
Joseph
joseph.sa...@gmail.com
Ted Bennett wrote:
> jobst....@stanfordalumni.org wrote:
>
> > Joseph Santaniello writes:
>
> > > I am by no means convinced that tubulars will be suitable for me, but
> > > these are the things I am taking into consideration.
> >
> > I think the comment that tubulars are more trouble than they are worth
> > is appropriate. That is why they are hardly used these days although
> > they were the only tires before about the 1980's.
> >
> > Jobst Brandt
>
> That comment will get the usual responses from others here, so here's
> mine: the first really fine bicycle I purchased was in 1980. New
> beaded tires were being introduced, and the claim was that they were
> just as good as tubulars. I got tubulars. That's what all the good
> bikes had, right? They were fine, and I didn't seem to get all that
> many flats (still don't). But even infrequent flats are a nuisance that
> is easier to deal with on a tire that isn't glued on.
>
> These days all my bikes except one wear clinchers. I do like the feel
> of the tubies, but the difference is so small and difficult to describe
> or measure that I'm just not willing to tolerate the disadvantages.
Due to my weight, I think I am more in tune to rolling resistance than
lighter riders, as rolling resistance is a larger percentage of my
total resistance. In other words, heavy riders notice a greater benefit
from better tires. It may be some sort of related yet non-quantifiable
reason that tubulars feel better, and perhaps this feel is more
pronounced for heavier riders.
But the disadvantages are real, so the point is still valid. Is it
worth it? I haven't had a flat (on my current clinchers) for several
thousand km, so I may in my mind underestimate the potential
aggravation from flatted tubulars. Patching them isn't a problem, I
kind of enjoy doing that. But the whole temporary nature of a replaced
tire on the road is a drag.
Joseph
Michael Warner
> Due to my weight, I think I am more in tune to rolling resistance than
> lighter riders, as rolling resistance is a larger percentage of my
> total resistance.
I suspect that your greater frontal area, and hence wind resistance
at a given speed, is much more significant in most conditions if the
tyres are properly inflated.
--
Home page: http://members.westnet.com.au/mvw
joseph.sa...@gmail.com
Yes, the larger area makes for a larger wind resistance too, but I
meant a larger relative percentage. In other words at a given speed my
RR may be 26% of my total resistance, while for a lighter rider it may
be 23%.
That was just a guess, but the "forces on rider" calculator at
analyticcycling.com supports it.
Joseph
Qui si parla Campagnolo
I have ridden tubies for 2 decades and granted, I have not ridden in
the Alps but I haven't had the problem of overheated rims causing
tubies to creep either, under braking. Colorado isn't flat, I go up and
down hills so unless you have the problems others have had, like in the
Alps, Vittoria or Conti glue, a solvent brush and a few minutes.
Qui si parla Campagnolo
jobst....@stanfordalumni.org wrote:
>
> I don't believe so. If your tires are bottoming on roads, then you
> are close to damaging rims and getting pinch flats anyway. I think
> you need a suspension bicycle if the roads are that bad. Running
> small soft tires is not a reasonable solution as I see it. I suspect
> you gained some weight since you last rode tubulars.
Hmmm. I am 200 pounds...have NEVER had a pinch flat on tubies, I use
95psi...
Don't ask Jobst for any advise about tubulars. He hates them and those
that use them. He hasn't seen or used a tubular for as long as I have
been using them. His knowledge is not current, on these and other
subjects.
Qui si parla Campagnolo
jobst....@stanfordalumni.org wrote:
>
> I think the comment that tubulars are more trouble than they are worth
> is appropriate. That is why they are hardly used these days although
> they were the only tires before about the 1980's.
>
> Jobst Brandt
Appropriate for you, too much trouble for you. Let the guy make up his
own mind, as to 'trouble' or 'mess' or any other 'lore'.
Qui si parla Campagnolo
Ted Bennett 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-
>
> Sheldon Brown sums it up well on http://sheldonbrown.com/tires.html :
>
> "Tubulars are considerably more expensive than clinchers of comparable
> performance.
Not true. Continental Sprinters and Vittoria CX are very comparible to
GP3000/4000 in constuction methods and are comparible in price. Same
for lower end tubies and clinchers.
>
> Tubulars are very much harder to repair once punctured. Most people
> just throw them away.
"Harder' to repair than clinchers no doubt but not hard to do at all.
>
> You need to carry a complete spare tubular in case you get a flat.
> This negates the weight advantage over clinchers, unless you have a team
> car following you with spare wheels.
Unlerss you also as a clincher rider, carry a foldable tire, which many
do, in case of a cut sidewall. Most tubie users, like me, use them NOT
for the 'weight' savings anyway.
>
> If you replace a tubular on the road, you cannot corner safely at high
> speeds until you go home and re-glue the tire. For safe high-speed
> cornering, the glue needs to dry for at least several hours.
True, but often I have gone home after one of my infrequent flats and
found that after checking the tire, at 95psi, I didn't need to reglue
it.
>
> Tubulars have higher rolling resistance than the best clinchers.
>
True...but in the grand scheme of things, the differences are teeny,
tiny and the 'advantages' of tubies, like the 95psi, supple feel far
outweigh any rolling resistence advantages for the majority of us
cyclists that just ride...
> Tubulars are rarely as true and round as clinchers.
Not true. The ones I use, even the low prices ones from Clement are
very round and true. Lots of low end Vittorias are not true at all, the
clinchers.
>
> Improperly glued tubulars can roll off the rim. This almost always
> causes a serious crash."
Flated clinchers, when decending and turning..will also cause the tire
to come off, resulting in the same type crash. I haven't had one of the
trubulars I have gluded roll in the 20 years I have been doing it. For
customers or myself.
So, let the gent decide for himself...the great tire debate continues
un abated...
>
> --
> Ted Bennet
SocSecTr...@earthlink.net
Qui si parla Campagnolo wrote:
> > just throw them away.
>
> "Harder' to repair than clinchers no doubt but not hard to do at all.
Easier on the road where you quickly replace the tire; fixing the tire
can be very easy with Tufo sealant which will repair many flats without
even opening the casing.
> > If you replace a tubular on the road, you cannot corner safely at high
> > speeds until you go home and re-glue the tire. For safe high-speed
> > cornering, the glue needs to dry for at least several hours.
>
> True, but often I have gone home after one of my infrequent flats and
> found that after checking the tire, at 95psi, I didn't need to reglue
> it.
Who corners at 10/10ths all the time, anyway? If you do that *every*
time you go around a curve you are going to be doing a lot of crashing
because of occasional sand or whatever. For the speeds that rational
people do outside of racing or descending, a tubular after a tire
change will be plenty safe. If you have to ride down a mountain, slow
down a little.
> > Tubulars have higher rolling resistance than the best clinchers.
>
> True...but in the grand scheme of things, the differences are teeny,
> tiny and the 'advantages' of tubies, like the 95psi, supple feel far
> outweigh any rolling resistence advantages for the majority of us
> cyclists that just ride...
I still don't think this has been proven, only that many tubulars have
higher RR than the best clinchers.
> > Improperly glued tubulars can roll off the rim. This almost always
> > causes a serious crash."
>
> Flated clinchers, when decending and turning..will also cause the tire
> to come off, resulting in the same type crash. I haven't had one of the
> trubulars I have gluded roll in the 20 years I have been doing it. For
> customers or myself.
Me either. You have to do an unbelievably crappy glue job to get a tire
to roll off.
SocSecTr...@earthlink.net
joseph.sa...@gmail.com wrote:
> Howdy,
>
> I am considering going back to tubulars, but one of the issues that was
> most problematic for me using them in the past was the glue melting
> during heavy braking. I weigh 95-100 kg so it doesn't take too much
> breaking to get generate lots of heat, and the braking forces are high
> too, so the tires slide around on the rim a lot. This is not good. I
> used 3M Fast Tack for a while but it seemed to kill the base tapes. I
> haven't had to use glue for many years now.
3M is not a good choice for tubular glue. Despite Brandt's claims to
the contrary, glue *does* make a difference in heat resistance, and
unlike Brandt, I can point you to hard evidence to support my
statement:
http://www.engr.ku.edu/~kuktl/bicycle/Part6.pdf
At 60oC Vittoria MastikOne has more bond strength than 3M at a normal
operating temperature of half that. Also, the Vittoria glue reaches a
bond strength in one hour that is approximately the same as 3M after 50
hours:
http://www.engr.ku.edu/~kuktl/bicycle/Part5.pdf
Can temps get higher than 60oC in descents? Maybe. Can even Vittoria
get hot enough in a descent to get it squirmy? Maybe. But the *facts*
show that there is an important difference in heat resistance among
tubular glues, and that at temperatures at which all other glues weaken
significantly, Vittoria MastikOne stays stronger than most of the
others were in the first place.
I have no stake in Vittoria, BTW, but this is the definitive answer
based on the body of research that exists at present.
PK
pain. I don't get many punctures because I fitt Flint catchers. I glue them
with double sided tape and have never had a problem. I carry two spare tubs
and one roll of double sided tape which does two tubs.
PK
Someone
jobst....@stanfordalumni.org aka Jobst Brandt wrote:
> ...
> I think the comment that tubulars are more trouble than they are worth
> is appropriate. That is why they are hardly used these days although
> they were the only tires before about the 1980's.
But clincher tire users miss out on inhaling glue fumes when mounting
tires. Maybe this explains why some like tubular tires so much. ;)
--
Tom Sherman - Fox River Valley
Mike Krueger
> Sheldon Brown sums it up well on http://sheldonbrown.com/tires.html :
>
> "Tubulars are considerably more expensive than clinchers of comparable
> performance.
>
> Tubulars are very much harder to repair once punctured. Most people
> just throw them away.
>
> You need to carry a complete spare tubular in case you get a flat.
> This negates the weight advantage over clinchers, unless you have a team
> car following you with spare wheels.
>
> If you replace a tubular on the road, you cannot corner safely at high
> speeds until you go home and re-glue the tire. For safe high-speed
> cornering, the glue needs to dry for at least several hours.
>
> Tubulars have higher rolling resistance than the best clinchers.
>
> Tubulars are rarely as true and round as clinchers.
>
> Improperly glued tubulars can roll off the rim. This almost always
> causes a serious crash."
As someone who actually rides tubulars, please allow me to state some
facts:
Tubular tires are far less prone to pinch flats, regardless of what
others here have claimed.
Any tubular has a far greater range of acceptable inflation pressures,
without risking pinch flats or blowing off the rim.
A flatted tubular will stay on the rim, which is both safer and more
advantageous in a race or where it is simply not convenient to stop.
A tubular is much faster and easier to change on the road. Your riding
buddies will appreciate this.
Tubular rims are less prone to impact damage because they don't have
bead edges to get dinged if you hit a pothole.
Tubular rim extrusions have a higher strength-to-weight ratio than
comparable clincher rims (see above).
There is a right way and a wrong way to do everything. A properly glued
tubular will not roll off the rim, and a pre-glued spare will stay on
the rim under normal circumstances if you do have to change it on the
road. The vast majority of cyclists do not ride in high mountains on a
regular basis where melting glue would ever be an issue. Also, tubulars
can be professionally repaired for $16 by TireAlert! if you can't do it
yourself. This is more than a clincher inner tube, but it's not like
you have to throw the tire away.
I weigh 180 lbs. I have several pairs of tubular wheels. My favorite
pair are built with Mavic GL330 rims (354 grams), 15g spokes, and
700x24C Clement Paris-Roubaix tires (269 grams). These wheels are
light, comfortable, and durable. I buy the tires for only $43 each (I
have a friend, but similar discounts are available if you buy tires
mail-order from the UK).
jobst....@stanfordalumni.org
>>> Due to my weight, I think I am more in tune to rolling resistance
>>> than lighter riders, as rolling resistance is a larger percentage
>>> of my total resistance.
>> I suspect that your greater frontal area, and hence wind resistance
>> at a given speed, is much more significant in most conditions if the
>> tyres are properly inflated.
> Yes, the larger area makes for a larger wind resistance too, but I
> meant a larger relative percentage. In other words at a given speed
> my RR may be 26% of my total resistance, while for a lighter rider
> it may be 23%.
I don't believe that RR is anywhere near that value considering that
wind drag increases as the square of velocity while RR is constant.
For what speed are you evaluating this. Wind POWER is V^3 and RR is
V^1.
> That was just a guess, but the "forces on rider" calculator at
> analyticcycling.com supports it.
There must be some mistake. Consider the chart:
http://www.sheldonbrown.com/brandt/rolling-resistance-tubular.html
Jobst Brandt
jobst....@stanfordalumni.org
>> I don't believe so. If your tires are bottoming on roads, then you
>> are close to damaging rims and getting pinch flats anyway. I think
>> you need a suspension bicycle if the roads are that bad. Running
>> small soft tires is not a reasonable solution as I see it. I
>> suspect you gained some weight since you last rode tubulars.
> Hmmm. I am 200 pounds...have NEVER had a pinch flat on tubies, I use
> 95psi...
I wouldn't make much hay on that. I have riding companions that
weigh 150 lbs who got pinch flats with tubulars. I can't imagine to
what roads you limit your rides but occasional pinch flats are a fact
of bicycling for active riders. That you haven't had heating problems
tells me that you haven't descended any twisty roads that require
constant braking, especially steep dirt roads, where high cornering
speeds are out of the question.
> Don't ask Jobst for any advise about tubulars. He hates them and
> those that use them. He hasn't seen or used a tubular for as long as
> I have been using them. His knowledge is not current, on these and
> other subjects.
You say that as though something about tubulars is different today
than when they were the mainstream of tires used by bikies. Can you
explain what that might be and how it prevents pinch flats or rim
heating? I hear this mantra of "tubulars are better today" without
supporting evidence.
As I see it, looking at tubulars that come across my way, they are no
easier to repair, some of them essentially not made to be repaired and
rim glues, as was posted here not long ago are no better than those of
yore, especailly Fastack.
Gluing tires on rims has not changed:
http://www.sheldonbrown.com/brandt/mounting-tubulars.html
Jobst Brandt
jobst....@stanfordalumni.org
>> I am considering going back to tubulars, but one of the issues that
>> was most problematic for me using them in the past was the glue
>> melting during heavy braking. I weigh 95-100 kg so it doesn't take
>> too much breaking to get generate lots of heat, and the braking
>> forces are high too, so the tires slide around on the rim a
>> lot. This is not good. I used 3M Fast Tack for a while but it
>> seemed to kill the base tapes. I haven't had to use glue for many
>> years now.
> 3M is not a good choice for tubular glue. Despite Brandt's claims to
> the contrary, glue *does* make a difference in heat resistance, and
> unlike Brandt, I can point you to hard evidence to support my
> statement:
http://www.engr.ku.edu/~kuktl/bicycle/Part6.pdf
Reading this article I see a report by someone who has never don
this. Rolling a tire is not the hazard of heated rim glues but rather
tire creep around the rim. It was regular practice for riders to turn
their front wheel around to get the bunched up tire to redistribute
the other way when descending on roads that caused continual braking.
Failure occurred from the valve stem being ripped out of the tube, not
rolling the tire. Besides that the temperatures investigated never
got to the level that cause serious problems and those are above 100
degrees C.
> At 60oC Vittoria MastikOne has more bond strength than 3M at a
> normal operating temperature of half that. Also, the Vittoria glue
> reaches a bond strength in one hour that is approximately the same
> as 3M after 50 hours:
http://www.engr.ku.edu/~kuktl/bicycle/Part5.pdf
> Can temps get higher than 60oC in descents? Maybe. Can even
> Vittoria get hot enough in a descent to get it squirmy? Maybe. But
> the *facts* show that there is an important difference in heat
> resistance among tubular glues, and that at temperatures at which
> all other glues weaken significantly, Vittoria MastikOne stays
> stronger than most of the others were in the first place.
> I have no stake in Vittoria, BTW, but this is the definitive answer
> based on the body of research that exists at present.
That this report focuses on rolling tires laterally off the rim is a
glaring failure investigate the heated glue problem. Worse yet is the
assumption that this is a linear function of adhesion vs. temperature
with almost no data in the graph. This rings of so much "bench
racing". Don't bet your safety on this "research".
from:
http://www.sheldonbrown.com/brandt/rolling-resistance-tubular.html
# That tubular tires move on rims, and often wear through their base
# tapes where they bear on the glued rim, was known but that it made a
# significant difference in rolling resistance was not.
You'll not that rim glue turns dark grey with use as it abrades the
aluminum rim. In fact the base tape wears through the anodizing if
that surface is anodized. Non-anodized rims develope cloth pattern
more rapidly in the contact surface from base tape motion without
descending under hard braking.
Jobst Brandt
Robin Hubert
For the uninitiated, gmf means "grams*meter force"?
Robin Hubert
jobst....@stanfordalumni.org
Ah yes, "tire savers", as they were known in some circles, were one of
those "tossing salt over the shoulder" quirks of bicycling, like
wiping tires. Among my riding companions the only thing they did was
to make obvious who had them on their bicycles when the roads were
wet, because the guy with tire savers was the rider with the dirtiest
legs. The number of flats had no apparent statistical difference.
The tire saver guys were there on Wednesday evenings at my weekly tire
patch sessions just like the others.
http://www.sheldonbrown.com/brandt/wiping.html
Jobst Brandt
joseph.sa...@gmail.com
analyticcycling.com has a nice side-by-side comparison for forces on
two riders. Plugging in a frontal area of .5 m2 for one rider and .65
m2 for rider 2, and a weight og 65kg for rider one and 95kg for rider
2, at 8.3 m/s(30mkh) with a rr coefficent of 0.006 to suit my rough
roads, I get:
Total drag in gmf for rider 1: 1,666
rider 2 total: 2,169
Wind for rider 1: 1,077
Wind rider 2: 1,400
RR for 1: 456
RR for 2: 636
RR is 27.4% of total for 65kg rider with a .5 m2 area, while RR is
29.4% of total for 95kg rider with .65 m2 frontal area.
Not a very big difference, but I maintain it is noticable. I cannot
ride a bike while weighing 30kg less than I do now, so it is impossible
for me to check, but a lighter person could load down their bike and
see if they notice the difference between tires more markedly, I guess.
Joseph
Someone
Mike Krueger wrote:
> ...
> A tubular is much faster and easier to change on the road. Your riding
Does water make a difference? If a rider with tubular tires has a flat
in the rain, it will be almost impossible to keep the portions of the
rim and tube that are glue covered dry, unless the rider is carrying a
tent or can find other covered shelter.
How does cold affect the bond when a tubular is replaced? Will the glue
be effective in below freezing temperatures?
Someone
> weigh 150 lbs who got pinch flats with tubulars. I can't imagine to
> what roads you limit your rides but occasional pinch flats are a fact
Maybe pinch flats are a fact of life for cyclists that use narrow
tires. I have not had any pinch flats, but then the narrowest tire I
use is 35-305 mm (and the widest are 53-406 and 53-559 mm).
jobst....@stanfordalumni.org
>>>>> Due to my weight, I think I am more in tune to rolling resistance
>>>>> than lighter riders, as rolling resistance is a larger percentage
>>>>> of my total resistance.
>>>> I suspect that your greater frontal area, and hence wind resistance
>>>> at a given speed, is much more significant in most conditions if the
>>>> tyres are properly inflated.
>>> Yes, the larger area makes for a larger wind resistance too, but I
>>> meant a larger relative percentage. In other words at a given speed
>>> my RR may be 26% of my total resistance, while for a lighter rider
>>> it may be 23%.
>> I don't believe that RR is anywhere near that value considering that
>> wind drag increases as the square of velocity while RR is constant.
>> For what speed are you evaluating this. Wind POWER is V^3 and RR is
>> V^1.
>>> That was just a guess, but the "forces on rider" calculator at
>>> analyticcycling.com supports it.
>> There must be some mistake. Consider the chart:
http://www.sheldonbrown.com/brandt/rolling-resistance-tubular.html
> For the uninitiated, gmf means "grams*meter force"?
Make that "grams force", there is no meter in that poem. This is in
lieu of dynes or newtons. Most people have an appreciation of one
gram and how small it is but far less of a dyne or newton.
http://www.m-w.com/dictionary/dyne
http://www.m-w.com/dictionary/newton
Jobst Brandt
Mike Krueger
Rim cement is not water-soluble. The tire will still stick to the rim,
otherwise any glued tubular would separate from the rim in the rain.
You should take care to keep dirt and mud from contaminating the glued
surfaces, though.
I don't ride outside when tempertures are below freezing, so I can't
answer your second question.
jobst....@stanfordalumni.org
>> ...
>> I wouldn't make much hay on that. I have riding companions that
>> weigh 150 lbs who got pinch flats with tubulars. I can't imagine to
>> what roads you limit your rides but occasional pinch flats are a fact
>> of bicycling for active riders...
> Maybe pinch flats are a fact of life for cyclists that use narrow
> tires. I have not had any pinch flats, but then the narrowest tire I
> use is 35-305 mm (and the widest are 53-406 and 53-559 mm).
Good for you. I have testified in an accident reconstruction where a
rider claimed ignorance of pinch flats on his fat MTB tire on which he
crashed and tried to place the blame on the rim strip. Pinch flats
have a clear diagnostic appearance that I can recognize without fail.
This guy was a semi-pro, sponsored racer.
I am sure he knew what he had done but tried to weedle out of it. I
think it was the usual routine in which his buddies got on him for
falling off his bicycle. So he concocted a story to cover his ego.
Then they insisted he sue the bike shop if that's how it happened and
there he was in court. Every court case I have testified on seemed to
have that origin. Machismo!
Jobst Brandt
G.T.
>
> Good for you. I have testified in an accident reconstruction where a
> rider claimed ignorance of pinch flats on his fat MTB tire on which he
> crashed and tried to place the blame on the rim strip. Pinch flats
> have a clear diagnostic appearance that I can recognize without fail.
> This guy was a semi-pro, sponsored racer.
>
> I am sure he knew what he had done but tried to weedle out of it. I
> think it was the usual routine in which his buddies got on him for
> falling off his bicycle. So he concocted a story to cover his ego.
> Then they insisted he sue the bike shop if that's how it happened and
> there he was in court. Every court case I have testified on seemed to
> have that origin. Machismo!
>
Can you elaborate on this? Somebody crashed because of a pinch flat and
he tried to blame it on a shop?
Greg
--
"All my time I spent in heaven
Revelries of dance and wine
Waking to the sound of laughter
Up I'd rise and kiss the sky" - The Mekons
jobst....@stanfordalumni.org
>> Good for you. I have testified in an accident reconstruction where
>> a rider claimed ignorance of pinch flats on his fat MTB tire on
>> which he crashed and tried to place the blame on the rim strip.
>> Pinch flats have a clear diagnostic appearance that I can recognize
>> without fail. This guy was a semi-pro, sponsored racer.
>> I am sure he knew what he had done but tried to wheedle out of it.
>> I think it was the usual routine in which his buddies got on him
>> for falling off his bicycle. So he concocted a story to cover his
>> ego. Then they insisted he sue the bike shop if that's how it
>> happened and there he was in court. Every court case I have
>> testified on seemed to have that origin. Machismo!
> Can you elaborate on this? Somebody crashed because of a pinch flat
> and he tried to blame it on a shop?
He claimed the pinch flat cut in the tube was caused by a faulty rim
tape that the bicycle shop had installed. John Forester testified for
the plaintiff that this was obviously the fault of the rim tape.
Photos made with grazing incidence light showed the cord pattern of
the tire casing embossed across the gash in the tube. When a tube is
pinched to the extent that it separates from compression, the tire
casing leaves 45 degree cord marks that straddle the "cut". I knew to
look for this from having patched many punch flats on latex and butyl
tubes. It was from this experience that I coined the term snake bite,
because riders using latex tubes often did not see the second hole.
Jobst Brandt
G.T.
> Greg T? writes:
>
>
>>>Good for you. I have testified in an accident reconstruction where
>>>a rider claimed ignorance of pinch flats on his fat MTB tire on
>>>which he crashed and tried to place the blame on the rim strip.
>>>Pinch flats have a clear diagnostic appearance that I can recognize
>>>without fail. This guy was a semi-pro, sponsored racer.
>
>
>>>I am sure he knew what he had done but tried to wheedle out of it.
>>>I think it was the usual routine in which his buddies got on him
>>>for falling off his bicycle. So he concocted a story to cover his
>>>ego. Then they insisted he sue the bike shop if that's how it
>>>happened and there he was in court. Every court case I have
>>>testified on seemed to have that origin. Machismo!
>
>
>>Can you elaborate on this? Somebody crashed because of a pinch flat
>>and he tried to blame it on a shop?
>
>
> He claimed the pinch flat cut in the tube was caused by a faulty rim
> tape that the bicycle shop had installed.
And what damages was he suing for? Was he seriously injured?
PK
<jobst....@stanfordalumni.org> wrote in message
news:43b9709a$0$58044$742e...@news.sonic.net...
> Peter Kidwell writes:
>
>> I like running sprnts and tubs even though mending a puncture in a
>> tub is a pain. I don't get many punctures because I fitt Flint
>> catchers. I glue them with double sided tape and have never had a
>> problem. I carry two spare tubs and one roll of double sided tape
>> which does two tubs.
>
> Ah yes, "tire savers", as they were known in some circles, were one of
> those "tossing salt over the shoulder" quirks of bicycling, like
> wiping tires. Among my riding companions the only thing they did was
> to make obvious who had them on their bicycles when the roads were
> wet, because the guy with tire savers was the rider with the dirtiest legs
I attach the flint catcher under the mudguards.
The number of flats had no apparent statistical difference.
Do you keep stats. on flats ? bit nerdy
> The tire saver guys were there on Wednesday evenings at my weekly tire
> patch sessions just like the others.
You may have noted that in a little book to apply statistical calcs to the
data .
>
> http://www.sheldonbrown.com/brandt/wiping.html
>
> Jobst Brandt
PK
<jobst....@stanfordalumni.org> wrote in message
news:43b98249$0$58044$742e...@news.sonic.net...
> Tom Sherman writes:
>
>>> ...
>>> I wouldn't make much hay on that. I have riding companions that
>>> weigh 150 lbs who got pinch flats with tubulars. I can't imagine to
>>> what roads you limit your rides but occasional pinch flats are a fact
>>> of bicycling for active riders...
>
>> Maybe pinch flats are a fact of life for cyclists that use narrow
>> tires. I have not had any pinch flats, but then the narrowest tire I
>> use is 35-305 mm (and the widest are 53-406 and 53-559 mm).
>
> Good for you. I have testified in an accident reconstruction where a
> rider claimed ignorance of pinch flats on his fat MTB tire on which he
> crashed and tried to place the blame on the rim strip. Pinch flats
> have a clear diagnostic appearance that I can recognize without fail
. It's not rocket science The pinch causes two small holes close together
like a snake bite .
> This guy was a semi-pro, sponsored racer.
>
> I am sure he knew what he had done but tried to weedle out of it. I
> think it was the usual routine in which his buddies got on him for
> falling off his bicycle. So he concocted a story to cover his ego.
> Then they insisted he sue the bike shop if that's how it happened and
> there he was in court. Every court case I have testified on seemed to
> have that origin. Machismo!
>
> Jobst Brandt
Seemed to, if, what a load of nonsence.
Benjamin Lewis
> As someone who actually rides tubulars, please allow me to state some
> facts:
> Tubular tires are far less prone to pinch flats, regardless of what
> others here have claimed.
Less than clinchers with latex tubes? Why should we believe this? Mere
experience isn't good enough, when others with experience make opposite
claims.
> Also, tubulars can be professionally repaired for $16 by TireAlert! if
> you can't do it yourself. This is more than a clincher inner tube, but
> it's not like you have to throw the tire away.
It's also as much as some decent clincher tires (e.g. you can currently buy
a Continental Sport 1000 at Nashbar for $7.48 US), and why throw away a
perfectly good inner tube?
--
Benjamin Lewis
Now is the time for all good men to come to.
-- Walt Kelly
Robin Hubert
> <jobst....@stanfordalumni.org> wrote in message
> news:43b9709a$0$58044$742e...@news.sonic.net...
>
>>Peter Kidwell writes:
>>
>>
>>>I like running sprnts and tubs even though mending a puncture in a
>>>tub is a pain. I don't get many punctures because I fitt Flint
>>>catchers. I glue them with double sided tape and have never had a
>>>problem. I carry two spare tubs and one roll of double sided tape
>>>which does two tubs.
>>
>>Ah yes, "tire savers", as they were known in some circles, were one of
>>those "tossing salt over the shoulder" quirks of bicycling, like
>>wiping tires. Among my riding companions the only thing they did was
>>to make obvious who had them on their bicycles when the roads were
>>wet, because the guy with tire savers was the rider with the dirtiest legs
>
>
> I attach the flint catcher under the mudguards.
>
> The number of flats had no apparent statistical difference.
> Do you keep stats. on flats ? bit nerdy
>
Well, if by "keeping stats", you mean to pay particular attention to the
incidence of flats with and without one remedy or another then, yes, one
does keep stats. Keen observers notice these things. It's just like
working in a bike ship, you'd notice that kevlar belted tires rate no
better than non-belted tires, but you couldn't convince the one guy, who
swears of one improvement, whereas another fellow gives a completely
contrasting anecdote.
>>The tire saver guys were there on Wednesday evenings at my weekly tire
>>patch sessions just like the others.
>
> You may have noted that in a little book to apply statistical calcs to the
> data .
????
>>http://www.sheldonbrown.com/brandt/wiping.html
>>
>>Jobst Brandt
>
>
Robin Hubert
Mike Krueger
Benjamin Lewis wrote:
> Mike Krueger wrote:
>
> > As someone who actually rides tubulars, please allow me to state some
> > facts:
> > Tubular tires are far less prone to pinch flats, regardless of what
> > others here have claimed.
>
> Less than clinchers with latex tubes? Why should we believe this? Mere
> experience isn't good enough, when others with experience make opposite
> claims.
Believe what you want. I attribute my own claims to the 40,000 miles I
have ridden on tubulars without a single pinch flat. Prior to that, I
was plagued with pinch flats on clinchers, or had to inflate them to
teeth-rattling pressures. Those here claiming that tubular pinch-flat
as often as clinchers also freely admit that they haven't ridden a
tubular tire in over 20 years! If that's your idea of experience...
> > Also, tubulars can be professionally repaired for $16 by TireAlert! if
> > you can't do it yourself. This is more than a clincher inner tube, but
> > it's not like you have to throw the tire away.
>
> It's also as much as some decent clincher tires (e.g. you can currently buy
> a Continental Sport 1000 at Nashbar for $7.48 US), and why throw away a
> perfectly good inner tube?
I'm sure you enjoy the comfort and performance of your $7 tires, but,
given the choice, I'll stick with my top-of-the-line professional
racing tubulars. And, to address your third point, what's "perfectly
good" about an inner tube with a hole in it?
jobst....@stanfordalumni.org
>>>> ...
>>>> I wouldn't make much hay on that. I have riding companions that
>>>> weigh 150 lbs who got pinch flats with tubulars. I can't imagine to
>>>> what roads you limit your rides but occasional pinch flats are a fact
>>>> of bicycling for active riders...
>>> Maybe pinch flats are a fact of life for cyclists that use narrow
>>> tires. I have not had any pinch flats, but then the narrowest tire I
>>> use is 35-305 mm (and the widest are 53-406 and 53-559 mm).
>> Good for you. I have testified in an accident reconstruction where a
>> rider claimed ignorance of pinch flats on his fat MTB tire on which he
>> crashed and tried to place the blame on the rim strip. Pinch flats
>> have a clear diagnostic appearance that I can recognize without fail
> It's not rocket science The pinch causes two small holes close
> together like a snake bite .
Not in this case. This caused a linear pinch that could be
interpreted as caused by a stiff rim tape except that it had all the
wrong characteristics. It was not two holes side by side. That's why
this wise guy tried to pull this off.
>> This guy was a semi-pro, sponsored racer.
>> I am sure he knew what he had done but tried to wheedle out of it. I
>> think it was the usual routine in which his buddies got on him for
>> falling off his bicycle. So he concocted a story to cover his ego.
>> Then they insisted he sue the bike shop if that's how it happened and
>> there he was in court. Every court case I have testified on seemed to
>> have that origin. Machismo!
> Seemed to, if, what a load of nonsence.
Oh? You were there and heard the testimony I presume.
Jobst Brandt
Someone
Jobst Brandt <jobst....@stanfordalumni.org> wrote:
> Robin Hubert writes:
>
> ...
> > For the uninitiated, gmf means "grams*meter force"?
>
> Make that "grams force", there is no meter in that poem. This is in
> lieu of dynes or newtons. Most people have an appreciation of one
> gram and how small it is but far less of a dyne or newton.
Nonsense. Most people are familiar with newtons [1], although some
consider apple and raspberry newton consumption to be heretical, with
the only true newton having a fig filling.
The newton is of course named after Newton, Massachusetts (where
Sheldon Brown hangs out).
[1] <http://www.healthierliving.org/nutrition/graphics/newtons.jpg>.
Someone
Mike Krueger wrote:
> Someone wrote:
> > Mike Krueger wrote:
> > > ...
> > > A tubular is much faster and easier to change on the road. Your riding
> > > buddies will appreciate this....
> >
> > Does water make a difference? If a rider with tubular tires has a flat
> > in the rain, it will be almost impossible to keep the portions of the
> > rim and tube that are glue covered dry, unless the rider is carrying a
> > tent or can find other covered shelter.
> >
> > How does cold affect the bond when a tubular is replaced? Will the glue
> > be effective in below freezing temperatures?
>
> Rim cement is not water-soluble. The tire will still stick to the rim,
Two different situations. I was referring to surface water possibly
preventing a bond from occurring between the glue on the tubular and
the glue on the rim when the spare is mounted, not water affecting the
glue on the already mounted tire as a solvent. If one dismounts a flat
tubular in the rain, and then attempts to mount a pre-glued replacement
tubular to the rim, does the water that will inevitably get on the glue
surface prior to mounting affect the strength of the bond?
joseph.sa...@gmail.com
Which mail-order shop in the UK that has 700x24C Clement Paris-Roubaix
tires?
Joseph
Someone
Jobst Brandt <jobst....@stanfordalumni.org> wrote:
> Tom Sherman writes:
>
> >> ...
> >> I wouldn't make much hay on that. I have riding companions that
> >> weigh 150 lbs who got pinch flats with tubulars. I can't imagine to
> >> what roads you limit your rides but occasional pinch flats are a fact
> >> of bicycling for active riders...
>
> > Maybe pinch flats are a fact of life for cyclists that use narrow
> > tires. I have not had any pinch flats, but then the narrowest tire I
> > use is 35-305 mm (and the widest are 53-406 and 53-559 mm).
>
> Good for you. I have testified in an accident reconstruction where a
> rider claimed ignorance of pinch flats on his fat MTB tire on which he
> crashed and tried to place the blame on the rim strip. Pinch flats
> have a clear diagnostic appearance that I can recognize without fail.
More information please. Was the rider using low pressure for
additional traction, or did he hit a sharp edge (e.g. rim of a pothole)
at high speed?
I do not ride fast where the pavement is very poor, and I use wider
tires than most road cyclists, which is a reasonable explanation why I
have not experienced any pinch flats.
Mike Krueger
> Mike Krueger wrote:
> > I weigh 180 lbs. I have several pairs of tubular wheels. My favorite
> > pair are built with Mavic GL330 rims (354 grams), 15g spokes, and
> > 700x24C Clement Paris-Roubaix tires (269 grams). These wheels are
> > light, comfortable, and durable. I buy the tires for only $43 each (I
> > have a friend, but similar discounts are available if you buy tires
> > mail-order from the UK).
>
> Which mail-order shop in the UK that has 700x24C Clement Paris-Roubaix
> tires?
Sorry, my comment was slightly misleading. The Clement Paris-Roubaix
tubulars are, in fact, quite hard to find at any price. My "friend"
gets those for me wholesale from the USA importer at that price.
UK supplier ProBikeKit.com sells top-of-the-line Vittoria CX tubulars
for about $39 each. That's a fantastic price, considering they retail
for $75-90 each here in the USA. I recently bought the last of their
700x24c Pave EVO CG's for $43 each, since I'm trying to corner the
market on the fatter tubulars before they become extinct ;>(
The 700x21.5c Vittoria CX's are slightly narrower, but ride really well
and are quite durable.
Sheldon Brown
>>
>> "Tubulars are considerably more expensive than clinchers of comparable
>>performance.
>>
>> Tubulars are very much harder to repair once punctured. Most people
>>just throw them away.
>>
>> You need to carry a complete spare tubular in case you get a flat.
>>This negates the weight advantage over clinchers, unless you have a team
>>car following you with spare wheels.
>>
>> If you replace a tubular on the road, you cannot corner safely at high
>>speeds until you go home and re-glue the tire. For safe high-speed
>>cornering, the glue needs to dry for at least several hours.
>>
>> Tubulars have higher rolling resistance than the best clinchers.
>>
>> Tubulars are rarely as true and round as clinchers.
>>
>> Improperly glued tubulars can roll off the rim. This almost always
>>causes a serious crash."
>
>
> As someone who actually rides tubulars, please allow me to state some
> facts:
FWIW, I used to "actually" ride tubulars too, but experience convinced
me they weren't worth the trouble, especially after I stopped being able
to buy Criterium Setas for $11 each...
> Tubular tires are far less prone to pinch flats, regardless of what
> others here have claimed.
Properly inflated clinchers don't commonly get pinch flats either. I
can't recall the last time I suffered a snakebite...
> There is a right way and a wrong way to do everything. A properly glued
> tubular will not roll off the rim, and a pre-glued spare will stay on
> the rim under normal circumstances if you do have to change it on the
> road.
Unless you flat on a rainy day...I learned this the hard way!
If you flat a tubular in the wet, your team car better be close behind
with a spare wheel for you...
Sheldon "Clinchers For Me" Brown
+----------------------------------------------------------+
| Everything looks worse in black and white --Paul Simon |
+----------------------------------------------------------+
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
Mike Krueger
I've done it a couple of times in the rain. Regardless of the water,
the residual glue and the air pressure in the inflated spare kept the
tire on and got me home. Not a scientific test, but I have enough
confidence in it to continue using tubulars. Then again, I don't
deliberately ride in the rain if I can avoid it, because as we all
know, you are far more likely to suffer a puncture on any tire when the
roads are wet.
Sheldon Brown
> Don't ask Jobst for any advise about tubulars. He hates them and those
> that use them.
That's uncalled for. He may not like tubulars, but there's no reason to
accuse him of hating those who use them.
> He hasn't seen or used a tubular for as long as I have
> been using them. His knowledge is not current, on these and other
> subjects.
Could you be more specific about what has changed in tubular technology
since Jobst switched over? Tubulars I see seem the same as they were 30
years ago, though perhaps the workmaship is a bit shoddier on the
cheaper models.
Are there now rim cements superior to Clement Red or 3M Fastack?
>
> Ted Bennett 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-
>
See above. I also don't sell leather hairnet helmets or slotted shoe
cleats. Does that indicate that I'm ignorant of those things...or might
it be that I've decided these are not products I can concienciously
recommend to my customers?
>
>>Sheldon Brown sums it up well on http://sheldonbrown.com/tires.html :
>>
>> "Tubulars are considerably more expensive than clinchers of comparable
>>performance.
>
>
> Not true. Continental Sprinters and Vittoria CX are very comparible to
> GP3000/4000 in constuction methods and are comparible in price. Same
> for lower end tubies and clinchers.
A quick Google finds the Sprinter selling for $68 at REI
The Vittoria CX is 69.95 at Lickton's.
I sell the Avocet FasGrip for $29.95, Panaracer Pasela for $19.95,
Panaracer Rolly-Poly for $49.95. I consider all of these superior to
the tubs you mention.
>> Tubulars are very much harder to repair once punctured. Most people
>>just throw them away.
>
> "Harder' to repair than clinchers no doubt but not hard to do at all.
>
Really? How long does it take you? When I used to do it it usually
took me about 45 minutes, with only about a 70% chance of success...
>> You need to carry a complete spare tubular in case you get a flat.
>>This negates the weight advantage over clinchers, unless you have a team
>>car following you with spare wheels.
>
> Unlerss you also as a clincher rider, carry a foldable tire, which many
> do, in case of a cut sidewall.
I usually carry a cut-up hunk from the sidewall of a discarded tubular
to use as a blow out patch in the event of a cut sidewall.
Some folks use dollar bills for this...
> Most tubie users, like me, use them NOT
> for the 'weight' savings anyway.
>
>> If you replace a tubular on the road, you cannot corner safely at high
>>speeds until you go home and re-glue the tire. For safe high-speed
>>cornering, the glue needs to dry for at least several hours.
>
>
> True, but often I have gone home after one of my infrequent flats and
> found that after checking the tire, at 95psi, I didn't need to reglue
> it.
But you don't _know_ it's that secure until you try to remove it.
>> Tubulars have higher rolling resistance than the best clinchers.
>
> True...but in the grand scheme of things, the differences are teeny,
> tiny and the 'advantages' of tubies, like the 95psi, supple feel far
> outweigh any rolling resistence advantages for the majority of us
> cyclists that just ride...
>
>> Tubulars are rarely as true and round as clinchers.
>
> Not true. The ones I use, even the low prices ones from Clement are
> very round and true. Lots of low end Vittorias are not true at all, the
> clinchers.
>
I stand by this one. Good Japanese clinchers are rounder than any
tubular I ever rode.
>
>> Improperly glued tubulars can roll off the rim. This almost always
>>causes a serious crash."
>
> Flated clinchers, when decending and turning..will also cause the tire
> to come off, resulting in the same type crash. I haven't had one of the
> trubulars I have gluded roll in the 20 years I have been doing it. For
> customers or myself.
I've never had a crash caused by a flatted clincher. I did once crash
due to a tubular rolling off (first bike I ever had with tubs, a used
bike where the previous owner had not installed the tub properly.)
> So, let the gent decide for himself...the great tire debate continues
> un abated...
Well, duh!
Sheldon "Clinchers For Me" Brown
+-----------------------------------------------------------------+
| When anyone asks me how I can best describe my experience |
| in nearly 40 years at sea, I merely say, "uneventful." |
| Of course, there have been many gales and storms and fog |
| and the like. But in all my experience, I have never been |
| in any accident of any sort worth speaking about. I have |
| never seen but one vessel in distress in all my years at sea. |
| I never saw a wreck and never have been wrecked, nor was I |
| ever in any predicament that threatened to end in disaster |
| of any sort. --E. J. Smith, Captain, RMS Titanic |
+-----------------------------------------------------------------+
Benjamin Lewis
>
> Benjamin Lewis wrote:
>> Mike Krueger wrote:
>>
>>> As someone who actually rides tubulars, please allow me to state some
>>> facts:
>>> Tubular tires are far less prone to pinch flats, regardless of what
>>> others here have claimed.
>>
>> Less than clinchers with latex tubes? Why should we believe this? Mere
>> experience isn't good enough, when others with experience make opposite
>> claims.
>
> Believe what you want. I attribute my own claims to the 40,000 miles I
> have ridden on tubulars without a single pinch flat. Prior to that, I
> was plagued with pinch flats on clinchers, or had to inflate them to
> teeth-rattling pressures.
Just to clarify -- you rode clinchers with latex tubes?
> Those here claiming that tubular pinch-flat as often as clinchers also
> freely admit that they haven't ridden a tubular tire in over 20 years! If
> that's your idea of experience...
... then what? Were the tubulars of 20 years ago more prone to pinch
flats? What has changed since then that invalidates the experience?
> I'm sure you enjoy the comfort and performance of your $7 tires, but,
> given the choice, I'll stick with my top-of-the-line professional
> racing tubulars. And, to address your third point, what's "perfectly
> good" about an inner tube with a hole in it?
What isn't, once you patch it?
John Forrest Tomlinson
>You say that as though something about tubulars is different today
>than when they were the mainstream of tires used by bikies. Can you
>explain what that might be and how it prevents pinch flats or rim
>heating?
On dealing with rim heating, it's quite likely that changes in rim
cement are making that less a problem.
The best rim cement was not available more than about ten years ago
(Vittoria Mastik 1 -- which is clear, not like the older red Vittoria
cement). It's possible that other brands of cement have also changed
in the last couple of decades. Certainly there was stuff in common
use 15 or 20 years ago that almost no one I know would dare to use
today -- like Tubasti.
JT
****************************
Remove "remove" to reply
Visit http://www.jt10000.com
****************************
John Forrest Tomlinson
but, in the long run, better solution for day-to-day riding.
John Forrest Tomlinson
<capt...@sheldonbrown.com> wrote:
>
>Are there now rim cements superior to Clement Red or 3M Fastack?
Continental and Vittoria Mastik 1.
Sheldon Brown
>
>>Are there now rim cements superior to Clement Red or 3M Fastack?
>
>
> Continental and Vittoria Mastik 1.
I've used the Continental stuff, found it inferior to both Clement red
and Fastack. In fact, the only time a customer shed blood and it was my
fault, it was when a tubular I had glued with Continental rolled off his
rim.
Vittoria stuff I've seen has appeared pretty much identical to Clement red.
I don't believe there has been any real improvement in tubulars in my
lifetime.
Newer tubulars I've seen have been notably inferior to the Clements and
Pirellis I used to ride.
I never had the opportunity to ride Dunlop tubulars, but from what I've
heard from the older folks, they were even better.
Sheldon "Clinchers Have Improved Greatly In My Lifetime" Brown
+--------------------------------------------------------+
| Daniel declined the tobacco with a wave of his hand. |
| "One day that Indian weed will kill more white men, |
| than white men have killed Indians." |
| Neal Stephenson - The System of the World |
+--------------------------------------------------------+
John Forrest Tomlinson
<capt...@sheldonbrown.com> wrote:
>I asked:
>>
>>>Are there now rim cements superior to Clement Red or 3M Fastack?
>>
>John Forrest Tomlinson replied"
>>
>> Continental and Vittoria Mastik 1.
>
>I've used the Continental stuff, found it inferior to both Clement red
>and Fastack. In fact, the only time a customer shed blood and it was my
>fault, it was when a tubular I had glued with Continental rolled off his
>rim.
In the last few years? I like Continental much more than Clement Red.
>Vittoria stuff I've seen has appeared pretty much identical to Clement red.
Vittoria Mastik 1 --- which is clear? The old Vittoria red seemed like
Clement Red, but the clear stuff seems to hold even tighter. At least
for me it's very very hard to remove tires installed with it.
jobst....@stanfordalumni.org
>>>> A tubular is much faster and easier to change on the road. Your
>>>> riding buddies will appreciate this...
>>> Does water make a difference? If a rider with tubular tires has a
>>> flat in the rain, it will be almost impossible to keep the
>>> portions of the rim and tube that are glue covered dry, unless the
>>> rider is carrying a tent or can find other covered shelter.
>>> How does cold affect the bond when a tubular is replaced? Will the
>>> glue be effective in below freezing temperatures?
>> Rim cement is not water-soluble. The tire will still stick to the
>> rim, otherwise any glued tubular would separate from the rim in the
>> rain...
> Two different situations. I was referring to surface water possibly
> preventing a bond from occurring between the glue on the tubular and
> the glue on the rim when the spare is mounted, not water affecting
> the glue on the already mounted tire as a solvent. If one dismounts
> a flat tubular in the rain, and then attempts to mount a pre-glued
> replacement tubular to the rim, does the water that will inevitably
> get on the glue surface prior to mounting affect the strength of the
> bond?
That tubular users cannot grasp this concept probably arises from not
patching tires on the road where a similar circumstance occurs. A
tube cannot be effectively patched when wet because water has a
greater affinity for surfaces (the tube) than rubber cement or for
that matter, tubular rim glue. A spare tire will not adhere
reasonably well if the rim is wet, even if it has a usable residue of
rim cement after pulling the flat tire off.
Jobst Brandt
jobst....@stanfordalumni.org
>> You say that as though something about tubulars is different today
>> than when they were the mainstream of tires used by bikies. Can
>> you explain what that might be and how it prevents pinch flats or
>> rim heating?
> On dealing with rim heating, it's quite likely that changes in rim
> cement are making that less a problem.
"Likely"! I thought you were reporting from some comparative
evaluation that you had made, not conjecture about what might be
better today than in the days of yore.
> The best rim cement was not available more than about ten years ago
> (Vittoria Mastik 1 -- which is clear, not like the older red
> Vittoria cement). It's possible that other brands of cement have
> also changed in the last couple of decades. Certainly there was
> stuff in common use 15 or 20 years ago that almost no one I know
> would dare to use today -- like Tubasti.
Yes, because someone like you might laugh at them for doing so without
knowing why. I have seen no indication that Vittoria glue is more
temperature insensitive than glues that I used with great success
after I fitted my wheels with thermal insulator strips. Even then, I
found the cost and tedium of sew-up repair not worth the effort... and
you are telling me that things are "likely" better today. I sense a
tubular tire chauvinist.
Jobst Brandt
jobst....@stanfordalumni.org
>>> As someone who actually rides tubulars, please allow me to state some
>>> facts:
>>> Tubular tires are far less prone to pinch flats, regardless of what
>>> others here have claimed.
This is "begging the question" as in debating. By claiming your
statement to be a "fact" you try to avoid showing why it should be
taken as fact.
http://www.nizkor.org/features/fallacies/begging-the-question.html
>> Less than clinchers with latex tubes? Why should we believe this? Mere
>> experience isn't good enough, when others with experience make opposite
>> claims.
> Believe what you want. I attribute my own claims to the 40,000
> miles I have ridden on tubulars without a single pinch flat. Prior
> to that, I was plagued with pinch flats on clinchers, or had to
> inflate them to teeth-rattling pressures. Those here claiming that
> tubular pinch-flat as often as clinchers also freely admit that they
> haven't ridden a tubular tire in over 20 years If that's your idea
> of experience...
So where do the pinch flats occur? The way you state that, we are all
incompetent, most of us having had a pinch flat on occasion with
tubulars and latex tubes. As I said, the term snake bite arose from
the occurrence when all bikies rode tubular tires with latex tubes.
You must be riding somewhere else when you ride than what athletic
bicyclists who get snake bites ride.
>>> Also, tubulars can be professionally repaired for $16 by
>>> TireAlert! if you can't do it yourself. This is more than a
>>> clincher inner tube, but it's not like you have to throw the tire
>>> away.
>> It's also as much as some decent clincher tires (e.g. you can
>> currently buy a Continental Sport 1000 at Nashbar for $7.48 US),
>> and why throw away a perfectly good inner tube?
> I'm sure you enjoy the comfort and performance of your $7 tires,
> but, given the choice, I'll stick with my top-of-the-line
> professional racing tubulars. And, to address your third point,
> what's "perfectly good" about an inner tube with a hole in it?
Well why didn't you say that at the outset instead of claiming that
those who don't use tubulars don't know what they are doing, and
implying they are inept riders?
Jobst Brandt
John Forrest Tomlinson
>John Forrest Tomlinson writes:
>
>>> You say that as though something about tubulars is different today
>>> than when they were the mainstream of tires used by bikies. Can
>>> you explain what that might be and how it prevents pinch flats or
>>> rim heating?
>
>> On dealing with rim heating, it's quite likely that changes in rim
>> cement are making that less a problem.
>
>"Likely"! I thought you were reporting from some comparative
>evaluation that you had made, not conjecture about what might be
>better today than in the days of yore.
>
Jobst, unlike you I don't presume/pretend to know everything, but am
willing to speculate openly, with my assumptions out in the open.
I'll ask you -- are you familiar enough with adhesives to say that it
is not possible that different glues might behave differently when
heated? If you know that for a fact, please share the information
with us.
If you don't know whether or not such differences can exist, it would
seem far more prudent of you to keep an open mind rather than
criticsing other people for speculation that is clearly labeled as
speculation.
So which is it? Do you know the possiblity I suggested cannot exist,
or are you just letting your anti-tubular bias lead to arrogant
ignorance.
>Yes, because someone like you might laugh at them for doing so without
>knowing why. I have seen no indication that Vittoria glue
> is more
>temperature insensitive than glues that I used with great success
>after I fitted my wheels with thermal insulator strips.
Have you conducted this test on current Vittoria glue (not the glue
from 20 years ago)? If you haven't, then you comments are besides the
point, which is that it possible that glues have changed.
So which Vittoria glue did you test and when?
> Even then, I
>found the cost and tedium of sew-up repair not worth the effort.
So do I. Why do you have bring random issues into the discussion of
glue melting?
Ryan Cousineau
"Qui si parla Campagnolo" <pe...@vecchios.com> wrote:
> Ted Bennett 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-
>
> >
> > Sheldon Brown sums it up well on http://sheldonbrown.com/tires.html :
> >
> > "Tubulars are considerably more expensive than clinchers of comparable
> > performance.
>
> Not true. Continental Sprinters and Vittoria CX are very comparible to
> GP3000/4000 in constuction methods and are comparible in price. Same
> for lower end tubies and clinchers.
Hm. On one hand, my tubular-riding friend thrives on picking up closeout
tubies. On the other hand, I get a local-racing-club deal from Kult
Bicycles (kultbike.com) that provides me with light, high-quality
clinchers that work great and are very cheap. Certainly less than what
my friend pays for his good tubulars.
> > You need to carry a complete spare tubular in case you get a flat.
> > This negates the weight advantage over clinchers, unless you have a team
> > car following you with spare wheels.
>
> Unless you also as a clincher rider, carry a foldable tire, which many
> do, in case of a cut sidewall. Most tubie users, like me, use them NOT
> for the 'weight' savings anyway.
I have used mylar granola/power bar wrappers and paper currency (both of
which are, ahem, dual-use technologies) more than once to repair
sidewall cuts. It works for return trips, though with the paper bill
it's a good idea to pull it out asap after the ride so the bill doesn't
get worn to a tatter. The mylar wrappers seem more durable, but does one
really want to ride around on a tire with a load-bearing granola bar
wrapper?
--
Ryan Cousineau rcou...@sfu.ca http://www.wiredcola.com/
"I don't want kids who are thinking about going into mathematics
to think that they have to take drugs to succeed." -Paul Erdos
jobst....@stanfordalumni.org
I see you want to go over the entire case. He descended Centennial
Dr. on his MTB past Lawrence Hall of Science and on the steep part of
the hill, at the botanical gardens, encountered a pot hole in the
pavement that could not be ridden. In the ensuing maneuver to avoid
the hole he hit a bump that cause a pinch flat. The subsequent
flat, at speed, caused a series of further cuts in the tire as he
continued before crashing and getting some skin abrasions.
More untruths in plaintiff's deposition emerged the farther the
incident was investigated. I was satisfied that the principal claim
against the bicycle shop was fabricated and that this could be proven
unambiguously.
Jobst Brandt
jobst....@stanfordalumni.org
>>>> You say that as though something about tubulars is different today
>>>> than when they were the mainstream of tires used by bikies. Can
>>>> you explain what that might be and how it prevents pinch flats or
>>>> rim heating?
>>> On dealing with rim heating, it's quite likely that changes in rim
>>> cement are making that less a problem.
>> "Likely"! I thought you were reporting from some comparative
>> evaluation that you had made, not conjecture about what might be
>> better today than in the days of yore.
> Jobst, unlike you I don't presume/pretend to know everything, but am
> willing to speculate openly, with my assumptions out in the open.
I never suggested you know anything about this. Why would you assume
you know "everything". You are the one who brought this up while
arguing that present day adhesives are better than the ones I used.
> I'll ask you -- are you familiar enough with adhesives to say that it
> is not possible that different glues might behave differently when
> heated? If you know that for a fact, please share the information
> with us.
Enough to say categorically that all pressure sensitive glues are
thermally unstable, becoming more liquid with increasing temperature.
That is why track (hard) glue exists for applications where reuse of
the adhesive is not required.
> If you don't know whether or not such differences can exist, it
> would seem far more prudent of you to keep an open mind rather than
> criticsing other people for speculation that is clearly labeled as
> speculation.
Your use of the subjunctive doesn't get you any free milage in arguing
that the age old problems surrounding tubular tires have been solved.
I guess you cannot imagine that there are scientific phenomena that
can be known and that all the conjecture you can muster won't change
that. What you propose is what seems prevalent in these discussions:
that there are no facts, only opinions, and the more people who hold
an opinion the more "factual" it is. The word "fact" being loosely
used in this forum as a variable, where it is used to beg the
question.
> So which is it? Do you know the possiblity I suggested cannot exist,
> or are you just letting your anti-tubular bias lead to arrogant
> ignorance.
I think you must have joined wreck.bike yesterday. I have stated
where the matter lies often enough over the last ten years or more as
well as in this thread. Don't belabor the question. In any case, if
you must ask, you shouldn't be telling this forum how much better
tubular glues work today than yesterday.
>> Yes, because someone like you might laugh at them for doing so
>> without knowing why. I have seen no indication that Vittoria glue
>> is more temperature insensitive than glues that I used with great
>> success after I fitted my wheels with thermal insulator strips.
> Have you conducted this test on current Vittoria glue (not the glue
> from 20 years ago)? If you haven't, then you comments are besides
> the point, which is that it possible that glues have changed.
Who wants to know. Have you conducted tests on current rim glues in
comparison to others? If not, you might do that instead of proposing
others do your research. You are the one making claims that there is
an improvement even though tests cited here show no such advances.
> So which Vittoria glue did you test and when?
This question is for you, not me.
>> Even then, I found the cost and tedium of sew-up repair not worth
>> the effort.
> So do I. Why do you have bring random issues into the discussion of
> glue melting?
This is a major issue and one that was a hazard for riders for all the
years tubulars were in general use.
Jobst Brandt
John Forrest Tomlinson
>
>Enough to say categorically that all pressure sensitive glues are
>thermally unstable, becoming more liquid with increasing temperature.
Do all pressure sensitive glues become equally unstable at any given
temperature, or can it vary? That is the issue I raised.
If you can't answer the question and haven't tested it, then my
speculation was quite valid and your bullying is lame.
>> Have you conducted this test on current Vittoria glue (not the glue
>> from 20 years ago)? If you haven't, then you comments are besides
>> the point, which is that it possible that glues have changed.
>
>Who wants to know. Have you conducted tests on current rim glues in
>comparison to others?
I haven't but given that we hear from "old timers" about glue melting
but less of that now, it seems extremely reasonalbe to speculate that
changes in glue could account for that. If you have facts or specific
knowledge to refute that please share them. Otherwise, you're just
being a bully and that doesn't work on me.
So -- do all road cements get soft at the same temperature? A simple
"I don't know; it's possible" will suffice.
Michael Press
John Forrest Tomlinson <usenet...@jt10000.com> wrote:
>
> I haven't but given that we hear from "old timers" about glue melting
> but less of that now,
That far fewer people run tubular tires can account for
`hearing less of that now'.
> it seems extremely reasonalbe to speculate that
> changes in glue could account for that.
All you bring is speculation, accusations, and demands
that others do your research for you. I do not care for
your speculations, because you have never shown technical
competence such as would pre-dispose me to entertain them.
> If you have facts or specific
> knowledge to refute that please share them.
Do it yourself. Tell us what you learn.
> Otherwise, you're just
> being a bully and that doesn't work on me.
Exactly how have you been bullied? I do not see it. If you
had been bullied, there are plenty of people on this forum
who would have said so. No, you do not get my sympathy.
You have not been bullied.
--
Michael Press
A Muzi
>>>>A tubular is much faster and easier to change on the road. Your riding
>>>>buddies will appreciate this....
>>Someone wrote:
>>>Does water make a difference? If a rider with tubular tires has a flat
>>>in the rain, it will be almost impossible to keep the portions of the
>>>rim and tube that are glue covered dry, unless the rider is carrying a
>>>tent or can find other covered shelter.
>>>How does cold affect the bond when a tubular is replaced? Will the glue
>>>be effective in below freezing temperatures?
> Mike Krueger wrote:
>>Rim cement is not water-soluble. The tire will still stick to the rim,
>>otherwise any glued tubular would separate from the rim in the rain....
Someone wrote:
> Two different situations. I was referring to surface water possibly
> preventing a bond from occurring between the glue on the tubular and
> the glue on the rim when the spare is mounted, not water affecting the
> glue on the already mounted tire as a solvent. If one dismounts a flat
> tubular in the rain, and then attempts to mount a pre-glued replacement
> tubular to the rim, does the water that will inevitably get on the glue
> surface prior to mounting affect the strength of the bond?
>
It doesn't seem to make any difference. Water just won't
mix with the cement and a reasonably fresh glue layer is
plenty sticky in spite of a little water.
I've only changed a flat in the rain once, on a club ride.
No more or less miserable than any other flat in the rain.
Riding to any available shelter is a big difference from
just standing in the rain.
Today for example I finished errands and rode another mile
or so before returning to the shop to change indoors out of
the sleet. I'd rather ride a flat tubular (leaning back,
taking some pressure off the front wheel) a while than deal
with it by the side of the road.
Rainy days sure do disturb the normally compacted crud in
the pavement. Every piece it seems washes sharp side up. . .
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
A Muzi
Sheldon Brown wrote:
> I've never had a crash caused by a flatted clincher. I did once crash
> due to a tubular rolling off (first bike I ever had with tubs, a used
> bike where the previous owner had not installed the tub properly.)
Which is not all that common an event. Sounds horrible
anyway. If it happened to _me_ at a young age, I might have
abandoned tubulars too!
A Muzi
-snip-
> It's possible that other brands of cement have also changed
> in the last couple of decades. Certainly there was stuff in common
> use 15 or 20 years ago that almost no one I know would dare to use
> today -- like Tubasti.
I hear you. Although I also used Tubasti exclusively for
about 15 years, I sure wouldn't now. Some Tubasti tubes are
like tapioca (yes, lumpy) and some like heavy cream. Clear
cements are consistent - much better for achieving a thin
even edge-to-edge layer. Although I can't say I ever saw a
Tubasti-ed tire lift because of it, ya gotta wonder. . .
As another contributor mentioned recently it is not rocket
science to mount a tubular on a rim. _Somebody_ is buying
all that Tubasti, yet we don't see a rash of lifted tires.
joseph.sa...@gmail.com
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?
Joseph
PK
>> Ted Bennett 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-
>>
> See above. I also don't sell leather hairnet helmets or slotted shoe
> cleats. Does that indicate that I'm ignorant of those things...or might
> it be that I've decided these are not products I can concienciously
> recommend to my customers?
The choice of the customer is more important than what you can and can't
recommend. You have decided to let down a customer who needs a tub. Think
about it you from the customers side.
PK
Earl Bollinger
news:1136222880.0...@o13g2000cwo.googlegroups.com...
> Ted Bennett wrote:
>> Sheldon Brown sums it up well on http://sheldonbrown.com/tires.html :
>>
>> "Tubulars are considerably more expensive than clinchers of comparable
>> performance.
>>
>> just throw them away.
>>
>> This negates the weight advantage over clinchers, unless you have a team
>> car following you with spare wheels.
>>
>> speeds until you go home and re-glue the tire. For safe high-speed
>> cornering, the glue needs to dry for at least several hours.
>>
>>
>>
>> causes a serious crash."
>
> facts:
> Tubular tires are far less prone to pinch flats, regardless of what
> others here have claimed.
> without risking pinch flats or blowing off the rim.
> A flatted tubular will stay on the rim, which is both safer and more
> advantageous in a race or where it is simply not convenient to stop.
> A tubular is much faster and easier to change on the road. Your riding
> buddies will appreciate this.
> bead edges to get dinged if you hit a pothole.
> Tubular rim extrusions have a higher strength-to-weight ratio than
> comparable clincher rims (see above).
>
> There is a right way and a wrong way to do everything. A properly glued
> tubular will not roll off the rim, and a pre-glued spare will stay on
> the rim under normal circumstances if you do have to change it on the
> regular basis where melting glue would ever be an issue. Also, tubulars
> can be professionally repaired for $16 by TireAlert! if you can't do it
> yourself. This is more than a clincher inner tube, but it's not like
> you have to throw the tire away.
>
> pair are built with Mavic GL330 rims (354 grams), 15g spokes, and
> 700x24C Clement Paris-Roubaix tires (269 grams). These wheels are
> light, comfortable, and durable. I buy the tires for only $43 each (I
> have a friend, but similar discounts are available if you buy tires
> mail-order from the UK).
>
That saves a lot of hassle as to what to do with expensive flatted tubulars
for sure.
SocSecTr...@earthlink.net
> a shy person writes:
I may be a lot of things but I'm not shy.
> > 3M is not a good choice for tubular glue. Despite Brandt's claims to
> > the contrary, glue *does* make a difference in heat resistance, and
> > unlike Brandt, I can point you to hard evidence to support my
> > statement:
>
> http://www.engr.ku.edu/~kuktl/bicycle/Part6.pdf
>
> Reading this article I see a report by someone who has never don
> this. Rolling a tire is not the hazard of heated rim glues but rather
> tire creep around the rim.
It is reasonable to suppose that if the glue is resistant to softening
and allowing it to roll off, it would be resistant to softening in a
way that would allow it to creep around the tire. In fact, it is
completely absurd and grasping at straws to suggest otherwise. The fact
remains that there is a significant dfference among glues in heat
resistance.
> Besides that the temperatures investigated never
> got to the level that cause serious problems and those are above 100
> degrees C.
You have no hard evidence of that. Get a thermometer, and then tell us
what the temperature is. However, it is clear from the test that there
are temperatures where some glues, 3M for instance, are significantly
weakened, and Vittoria is completely safe.
> That this report focuses on rolling tires laterally off the rim is a
> glaring failure investigate the heated glue problem.
Bull$hit. Roll-off strength is a way of measuring the comparative
resistance of the glue to softening and relative strength of the bond,
and applies equally to creep or roll. The problem here for you is that
there is hard experimental evidence that exposes the position you have
taken for decades, that tubular road glues are hopelessly flawed by a
tendency to soften when heated, as complete and utter BS. The fact is
that there *is* a difference in glues, and that under any but the most
extreme conditions ( your fabled descents on steep unpaved Alpine roads
with constant braking to avoid having the bike slide out on
switchbacks) this difference is demonstrably significant. Furthermore,
there is no evidence that even under your
extreme-beyond-reality-for-99.99%-of-people (the roads in your scenario
were paved decades ago and if they're not they're properly ridden now
on MTBs) scenario that Vittoria glue would be inadequate.
> Worse yet is the
> assumption that this is a linear function of adhesion vs. temperature
> with almost no data in the graph.
No one makes that assumption. There is test evidence to show that there
is a difference in glues; the author explains also why they think the
temperature that they tested to is meaningful. If you have other hard
evidence involving a thermometer and a survey of the conditions that
people are likely to encounter that suggests that higher temperatures
are commonplace in mountain descents, please present it. The fact that
you got snow to sizzle on your wheels 40 years ago on unpaved Alpine
roads does not provide such evidence.
> This rings of so much "bench
> racing". Don't bet your safety on this "research".
What do you bet your safety on, then? Their research is well done.
Here's an idea: next time anyone wants to test their rim temperature
after a descent{ squirt your water bottle on the rim and see if the
water boils off. If it does, you have matched the extreme conditions
that Brandt managed to create; otherwise, you're more in the realm of
everyday reality tested by the researcher.
> You'll not that rim glue turns dark grey with use as it abrades the
> aluminum rim. In fact the base tape wears through the anodizing if
> that surface is anodized. Non-anodized rims develope cloth pattern
> more rapidly in the contact surface from base tape motion without
> descending under hard braking.
Irrelevant to this discussion, and probably not universally true.
Certainly not tested under any kind of controlled conditions, and not
my recent experience.
John Forrest Tomlinson
>In article <krujr1h0fi0jdm4dd...@4ax.com>,
> John Forrest Tomlinson <usenet...@jt10000.com> wrote:
>
>>
>> I haven't but given that we hear from "old timers" about glue melting
>> but less of that now,
>
>That far fewer people run tubular tires can account for
>`hearing less of that now'.
Sure, that's possible too.
>
>> it seems extremely reasonalbe to speculate that
>> changes in glue could account for that.
>
>All you bring is speculation, accusations, and demands
>that others do your research for you. I do not care for
>your speculations, because you have never shown technical
>competence such as would pre-dispose me to entertain them.
>
>> If you have facts or specific
>> knowledge to refute that please share them.
>
>Do it yourself. Tell us what you learn.
No -- this guy told me my speculation is wrong. I say it's possible.
I haven't proven it's possible -- that's why I label it is as
speculation. He's saying it's wrong -- that's an assertion of fact
that requires some backup. Otherwise Jobst should admit he's
speculating. Nothing wrong with that -- but I don't think he's
willing to come down off his high horse and admit that he's willing to
go by instinct/speculation whatever.
>
>> Otherwise, you're just
>> being a bully and that doesn't work on me.
>
>Exactly how have you been bullied? I do not see it. If you
>had been bullied, there are plenty of people on this forum
>who would have said so. No, you do not get my sympathy.
>You have not been bullied.
He's a bully because he jumps on speculation w/o specific knowledge or
alternate explanations and fuzzes over the issue with claims of
testing w/o offering specific info. You alternate explanation of the
paucity of reports on glues melting is the opposite -- a productive
attempt to find reasons for change
John Forrest Tomlinson
wrote:
I think what happens is people by the Tubasti once, then when putting
on the tire they notice it's not real confiendence-inspiring, so they
toss it and re-install. I know I did that once.
It's like candy corn -- the stuff is terrible but everyone tries it
once.
John Forrest Tomlinson
>
>Do you know of anyone who has tried the Schwalbe Stelvio 700x25
>tubulars?
I got a deal on Schwalbe stuff and got some of their tubulars in the
size narrower than that. Haven't used them yet, but they appear
well-constructed. The 700x25 are the same other than size, I think,
so if I can remember I'll report on the tires in April or May when I
use them.
John Forrest Tomlinson
>jobst....@stanfordalumni.org wrote:
>> a shy person writes:
>
>I may be a lot of things but I'm not shy.
>
>> > 3M is not a good choice for tubular glue. Despite Brandt's claims to
>> > the contrary, glue *does* make a difference in heat resistance, and
>> > unlike Brandt, I can point you to hard evidence to support my
>> > statement:
>>
>> http://www.engr.ku.edu/~kuktl/bicycle/Part6.pdf
>>
>> Reading this article I see a report by someone who has never don
>> this. Rolling a tire is not the hazard of heated rim glues but rather
>> tire creep around the rim.
>
>It is reasonable to suppose that if the glue is resistant to softening
>and allowing it to roll off, it would be resistant to softening in a
>way that would allow it to creep around the tire. In fact, it is
>completely absurd and grasping at straws to suggest otherwise. The fact
>remains that there is a significant dfference among glues in heat
>resistance.
Thanks.
On this issue it seems Jobst Brandt's claims that that isn't so were
themselves the sort of SPECULATION he denouces.
Qui si parla Campagnolo
Sheldon Brown wrote:
> Peter Chisholm scritta:
>
> > Don't ask Jobst for any advise about tubulars. He hates them and those
> > that use them.
>
> That's uncalled for. He may not like tubulars, but there's no reason to
> accuse him of hating those who use them.
Responses to me from Jobst, unlike your responses, have always been
rude, surly, condesending. I can only surmise he has a personal problem
with users of tubies, Delta brakes, tied and soldered wheel users.
>
> > He hasn't seen or used a tubular for as long as I have
> > been using them. His knowledge is not current, on these and other
> > subjects.
>
> Could you be more specific about what has changed in tubular technology
> since Jobst switched over? Tubulars I see seem the same as they were 30
> years ago, though perhaps the workmaship is a bit shoddier on the
> cheaper models.
More consistent, rounder, better materials(Conti specifically). The
Vittoria factory in Thailand is state of the art, MUCH better product,
both clincher and tubular. Not the arcane, cotton and silk hand made by
a gent in a dark room type tire. Better tread, glues, bodies, etc.
>
> Are there now rim cements superior to Clement Red or 3M Fastack?
Conti and Vittoria is what I use. I have no problems like stire creep
or rolling tires.
> >
> > Ted Bennett 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-
> >
> See above. I also don't sell leather hairnet helmets or slotted shoe
> cleats. Does that indicate that I'm ignorant of those things...or might
> it be that I've decided these are not products I can concienciously
> recommend to my customers?
Then don't recommend them. I don't recommend Sora shifters either. NOT
the point. Tubulars are still a viable alternative for tires on a road
steed. They have advantages, some I see when I ride them, like
yesterday. When is the last time you rode on tubulars for an extended
amount of time Sheldon? That's my point.
> >
> >>Sheldon Brown sums it up well on http://sheldonbrown.com/tires.html :
> >>
> >> "Tubulars are considerably more expensive than clinchers of comparable
> >>performance.
> >
> >
> > Not true. Continental Sprinters and Vittoria CX are very comparible to
> > GP3000/4000 in constuction methods and are comparible in price. Same
> > for lower end tubies and clinchers.
>
> A quick Google finds the Sprinter selling for $68 at REI
> The Vittoria CX is 69.95 at Lickton's.
And a Vittoria Open CX and latex tube is the same price. A GP-4000 is
$55, conti tube is $7, we sell Conti Sprinters for $64. You said
'considerably more expensive'..I guess 'considerable' means different
things to us.
>
> I sell the Avocet FasGrip for $29.95, Panaracer Pasela for $19.95,
> Panaracer Rolly-Poly for $49.95. I consider all of these superior to
> the tubs you mention.
Great. I don't sell Avocet, Panaracer or many others. 'Superior' is
also a subjective measutement.
>
> >> Tubulars are very much harder to repair once punctured. Most people
> >>just throw them away.
> >
> > "Harder' to repair than clinchers no doubt but not hard to do at all.
> >
> Really? How long does it take you? When I used to do it it usually
> took me about 45 minutes, with only about a 70% chance of success...
Undisturbed about 20 minutes tops. The hardest thing was finding the
right spot to open the seam.
>
> >> You need to carry a complete spare tubular in case you get a flat.
> >>This negates the weight advantage over clinchers, unless you have a team
> >>car following you with spare wheels.
> >
> > Unlerss you also as a clincher rider, carry a foldable tire, which many
> > do, in case of a cut sidewall.
>
> I usually carry a cut-up hunk from the sidewall of a discarded tubular
> to use as a blow out patch in the event of a cut sidewall.
Too heavy!!!!
>
> Some folks use dollar bills for this...In Boulder it has to be a $5 bill.
>
> > Most tubie users, like me, use them NOT
> > for the 'weight' savings anyway.
> >
> >> If you replace a tubular on the road, you cannot corner safely at high
> >>speeds until you go home and re-glue the tire. For safe high-speed
> >>cornering, the glue needs to dry for at least several hours.
> >
> >
> > True, but often I have gone home after one of my infrequent flats and
> > found that after checking the tire, at 95psi, I didn't need to reglue
> > it.
>
> But you don't _know_ it's that secure until you try to remove it.
Well, I can 'test it' on the road. The point is that it is not so
'dangerous' that you have to limp home..hardly riding at any speed.
With something that actually gets the pressure to 95psi, like CO2, no
prblems. Remember we are just ridin' alog here, not racing.
>
> >> Tubulars have higher rolling resistance than the best clinchers.
> >
> > True...but in the grand scheme of things, the differences are teeny,
> > tiny and the 'advantages' of tubies, like the 95psi, supple feel far
> > outweigh any rolling resistence advantages for the majority of us
> > cyclists that just ride...
> >
> >> Tubulars are rarely as true and round as clinchers.
> >
> > Not true. The ones I use, even the low prices ones from Clement are
> > very round and true. Lots of low end Vittorias are not true at all, the
> > clinchers.
> >
> I stand by this one. Good Japanese clinchers are rounder than any
> tubular I ever rode.
Okay, but like I stated, I sell Vittoria, Continental and Ritchey. Some
of the dual tread clinchers tires are not true at all.
> >
> >> Improperly glued tubulars can roll off the rim. This almost always
> >>causes a serious crash."
> >
> > Flated clinchers, when decending and turning..will also cause the tire
> > to come off, resulting in the same type crash. I haven't had one of the
> > trubulars I have gluded roll in the 20 years I have been doing it. For
> > customers or myself.
>
> I've never had a crash caused by a flatted clincher. I did once crash
> due to a tubular rolling off (first bike I ever had with tubs, a used
> bike where the previous owner had not installed the tub properly.)
>
> > So, let the gent decide for himself...the great tire debate continues
> > un abated...
>
> Well, duh!
>
My point is that clincher advantages are firmly in the grey area, and
no 'FAQ' demonstrates that they are a dumb idea. Some don't want to
glue their tires on, some don't want to reach for their shifters, some
want to tighten the strap on their pedals. For us non racers that just
ride along, each day, there is nothing black or white, in terms of
equipment.
Sandy
news:1136296539.0...@g14g2000cwa.googlegroups.com,
Qui si parla Campagnolo <pe...@vecchios.com> a réfléchi, et puis a déclaré :
>>> Not true. Continental Sprinters and Vittoria CX are very comparible
>>> to GP3000/4000 in constuction methods and are comparible in price.
>>> Same for lower end tubies and clinchers.
>>
>> A quick Google finds the Sprinter selling for $68 at REI
>> The Vittoria CX is 69.95 at Lickton's.
>
> And a Vittoria Open CX and latex tube is the same price. A GP-4000 is
> $55, conti tube is $7, we sell Conti Sprinters for $64. You said
> 'considerably more expensive'..I guess 'considerable' means different
> things to us.
While it's not a great racing tire, lots of guys in my club use a tubular
from the *supermarket'* which sells for 11,90. No problems with it as a
training tire, according to their reports. I don't ride them, but
experienced racers do.
>> I sell the Avocet FasGrip for $29.95, Panaracer Pasela for $19.95,
>> Panaracer Rolly-Poly for $49.95. I consider all of these superior to
>> the tubs you mention.
>
>>>> Tubulars are very much harder to repair once punctured. Most
>>>> people just throw them away.
>>>
>>> "Harder' to repair than clinchers no doubt but not hard to do at
>>> all.
Well, I wonder how may tubulars get punctured before they wear out. I think
rather few, and the guys here who prefer them (those cheap ones I mention
above), have (all the guys, all the rides) _never_ flatted during a year and
a half I have been with this club. On the other hand, there is usually a
flat on a clincher around every second ride.
>> Really? How long does it take you? When I used to do it it usually
>> took me about 45 minutes, with only about a 70% chance of success...
>
> Undisturbed about 20 minutes tops. The hardest thing was finding the
> right spot to open the seam.
> My point is that clincher advantages are firmly in the grey area, and
> no 'FAQ' demonstrates that they are a dumb idea. Some don't want to
> glue their tires on, some don't want to reach for their shifters, some
> want to tighten the strap on their pedals. For us non racers that just
> ride along, each day, there is nothing black or white, in terms of
> equipment.
Incidentally, I don't ride tubulars any more. I was never handy with the
glue.
--
Sandy
--
Il n'est aucune sorte de sensation qui soit plus vive
que celle de la douleur ; ses impressions sont sûres,
elles ne trompent point comme celles du plaisir.
- de Sade.
SocSecTr...@earthlink.net
Sheldon Brown wrote:
> I've used the Continental stuff, found it inferior to both Clement red
> and Fastack. In fact, the only time a customer shed blood and it was my
> fault, it was when a tubular I had glued with Continental rolled off his
> rim.
>
> Vittoria stuff I've seen has appeared pretty much identical to Clement red.
Well, I guess I would agree that it *appears* pretty much identical to
Clement red. However I wouldn't recommend making any assumptions about
its performance based on its appearance. In the tests under controlled
conditions its performance is vastly superior, and the evidence is
convincing enough that until someone comes up with new data that
suggests otherwise, it's case closed.
> I don't believe there has been any real improvement in tubulars in my
> lifetime.
>
> Newer tubulars I've seen have been notably inferior to the Clements and
> Pirellis I used to ride.
I don't know about Pirellis but it seems that I get fewer flats these
days than I did on the Clements I used to ride, although I am still
riding a twenty year old Clement Criterium (it hasn't been ridden
continuously) with a lot of miles on it. The two flats I had with it
have been fixed with Tufo sealant. I think that the really cheap
"training" tires I get are inferior to training tires from 20 years ago
and have given up on them but may try some of the ones I've seen
suggested here.
SocSecTr...@earthlink.net
> > I'll ask you -- are you familiar enough with adhesives to say that it
> > is not possible that different glues might behave differently when
> > heated? If you know that for a fact, please share the information
> > with us.
>
> Enough to say categorically that all pressure sensitive glues are
> thermally unstable, becoming more liquid with increasing temperature.
*Everything* is thermally unstable. You get it hot enough, the rim will
melt or burn; in fact it will turn into plasma. But making a statement
that something is thermally unstable is not the same as providing
experimentally derived hard data that that shows that the temperature
at which something becomes unstable is one at which there is more than
an extremely remote possibility of it occurring in real world operating
conditions.
Only a complete blockhead would continue to insist that there are no
meaningful differences among glues WRT heat resistance. The data is
there; it's black and white. The irony is that your own insistence that
your extreme example is important actually emphasizes the importance of
the difference. If your situation can occur then it follows that other
braking situations generating less heat will occur more frequently, and
since there is incontrovertible evidence that there is a significant
difference at those more frequently encountered temperatures, only a
fool would ignore the data and pick a glue that has less heat
resistance if they do any kind of riding down mountain roads.
> > If you don't know whether or not such differences can exist, it
> > would seem far more prudent of you to keep an open mind rather than
> > criticsing other people for speculation that is clearly labeled as
> > speculation.
>
> Your use of the subjunctive doesn't get you any free milage in arguing
> that the age old problems surrounding tubular tires have been solved.
The subjunctive has nothing to do with tubulars, it has to do with you.
You have spent decades arguing that the heat softening of glue is a
fatal flaw in tubulars, and now you have been proven wrong by hard
data.
> I guess you cannot imagine that there are scientific phenomena that
> can be known and that all the conjecture you can muster won't change
> that. What you propose is what seems prevalent in these discussions:
> that there are no facts, only opinions, and the more people who hold
> an opinion the more "factual" it is. The word "fact" being loosely
> used in this forum as a variable, where it is used to beg the
> question.
Wow. Projection. You use conjecture to question the facts of a solid
research paper with important experimental data, and then call it
conjecture and your own conjecture facts.
> > Have you conducted this test on current Vittoria glue (not the glue
> > from 20 years ago)? If you haven't, then you comments are besides
> > the point, which is that it possible that glues have changed.
>
> Who wants to know.
The OP.
> Have you conducted tests on current rim glues in
> comparison to others? If not, you might do that instead of proposing
> others do your research.
The research has been done.
> You are the one making claims that there is
> an improvement even though tests cited here show no such advances.
What it shows is that there is significant difference among glues WRT
heat resistance.
> > So which Vittoria glue did you test and when?
>
> This question is for you, not me.
The tests have been done. The data is there. If you want to question it
you will need to provide other data. In the meantime, case closed.
> > So do I. Why do you have bring random issues into the discussion of
> > glue melting?
>
> This is a major issue and one that was a hazard for riders for all the
> years tubulars were in general use.
It was not a notable hazard. With 30 years of tubular riding I have not
seen it to be an issue, was never warned about it by the European pros
I rode with in mountains 30 years ago, never saw them get off a bike
and turn the front wheel around. It may have been a hazard but it
occurred only under extreme, extreme circumstances- constantly riding
the brakes over long or very steep descents instead of using air
braking, or riding down unpaved switchedback roads. Whether or not
Vittoria glue would fail under that situation is open to conjecture-
neither you nor I know the answer because we don't know the rim
temperature under those conditions, and we don't know what that glue
would do above 60oC. What we do know, though, is that under conditions
that people are more likely to encounter, the right glue choice will
make a difference. It doesn't take a genius to figure out that there is
a range of operating temperature between 27o and 60oC (or higher if we
may be allowed some reasonable extrapolation) where Vittoria provides
an added margin of safety that other glues do not.
The answer to "Heat resistant tubular glue?"
Vittoria MastikOne.
joseph.sa...@gmail.com
> > > So do I. Why do you have bring random issues into the discussion of
> > > glue melting?
> >
> > This is a major issue and one that was a hazard for riders for all the
> > years tubulars were in general use.
>
> It was not a notable hazard. With 30 years of tubular riding I have not
> seen it to be an issue, was never warned about it by the European pros
> I rode with in mountains 30 years ago, never saw them get off a bike
> and turn the front wheel around. It may have been a hazard but it
> occurred only under extreme, extreme circumstances- constantly riding
> the brakes over long or very steep descents instead of using air
> braking, or riding down unpaved switchedback roads. Whether or not
</snip>
You never saw it because you lightweights dropped the 90+ kg guys so
bad that they were half an hour after you guys to the summit! ;-)
I have had the glue melt while on descents in the mountains of
Switzerland, Italy, Norway, and Southern California. Maybe in a race
with no worries of cars coming the other way I may have been able to
use the brakes less, but when one weighs 100kg, speed builds up fast
down a 10% grade! From experience it was plainly obvious that riding
the brakes was bad. I made a serious effort to do all braking as short
as possible to not generate excessive heat. The only time I ever rode
the brakes was only after the glue had already melted so bad that I had
to go at not much more than a walking pace.
If we say that any given corner has a more or less max possible
cornering speed, and a certain descent has any number of corners, how
much braking would a 100kg rider need to do to keep the speed down, vs
a 65kg rider? How much heat would this generate? Any math whizzes fell
like modeling this?
Joseph
joseph.sa...@gmail.com
John Forrest Tomlinson wrote:
> On 3 Jan 2006 00:24:48 -0800, joseph.sa...@gmail.com wrote:
>
> >
> >Do you know of anyone who has tried the Schwalbe Stelvio 700x25
> >tubulars?
>
> I got a deal on Schwalbe stuff and got some of their tubulars in the
> size narrower than that. Haven't used them yet, but they appear
> well-constructed. The 700x25 are the same other than size, I think,
> so if I can remember I'll report on the tires in April or May when I
> use them.
>
> JT
Any chance you could pump one up and measure it's width? If it has an
actual width of 22, ther eis reason to belive the 25's will actually be
25. If so I may be inclined to order some.
Joseph
jobst....@stanfordalumni.org
> I may be a lot of things but I'm not shy.
So why do you snipe anonymously?
>>> 3M is not a good choice for tubular glue. Despite Brandt's claims
>>> to the contrary, glue *does* make a difference in heat resistance,
>>> and unlike Brandt, I can point you to hard evidence to support my
>>> statement:
http://www.engr.ku.edu/~kuktl/bicycle/Part6.pdf
>> Reading this article I see a report by someone who has never done
>> this. Rolling a tire is not the hazard of heated rim glues but
>> rather tire creep around the rim.
> It is reasonable to suppose that if the glue is resistant to
> softening and allowing it to roll off, it would be resistant to
> softening in a way that would allow it to creep around the tire. In
> fact, it is completely absurd and grasping at straws to suggest
> otherwise. The fact remains that there is a significant dfference
> among glues in heat resistance.
Oh oh! Here is another hypothesizer speaking from the KBD rather than
actual use of tubulars. "It is reasonable to suppose " is not a
convincing testimony of fact. Of course there are no facts, it's all
opinion in your perspective.
>> Besides that the temperatures investigated never got to the level
>> that cause serious problems and those are above 100 degrees C.
> You have no hard evidence of that. Get a thermometer, and then tell
> us what the temperature is. However, it is clear from the test that
> there are temperatures where some glues, 3M for instance, are
> significantly weakened, and Vittoria is completely safe.
I see you also are a recent visitor here. In many of these "tubulars
are better" threads I explained where that was "researched" as I
descended The Nufenen Pass in the Alps after stream crossings and snow
riding only to believe I had a flat as the tire hissed on entry into
hairpin turns, but stopped "leaking" as soon as I let up on the
brakes. When the tire did not go flat I discovered upon stopping,
that steam was coming out of the stem hole. That settles the question
for me.
Can you explain why "Vittoria is completely safe"? What is
"completely safe" anyway, there being no evidence of that in the
report.
Just the same, thanks for defining experiments that I should do to
support your claims of advancing glue technology. I spent many years
riding tubulars and am fully familiar with their feet of clay as well
as their strong points.
http://www.sheldonbrown.com/brandt/mounting-tubulars.html
http://www.sheldonbrown.com/brandt/making-tubulars.html
http://www.sheldonbrown.com/brandt/tubular-repair.html
http://www.sheldonbrown.com/brandt/rolling-resistance-tubular.html
http://www.sheldonbrown.com/brandt/tubular-folding.html
>> That this report focuses on rolling tires laterally off the rim is
>> a glaring failure investigate the heated glue problem.
> Bull$hit. Roll-off strength is a way of measuring the comparative
> resistance of the glue to softening and relative strength of the
> bond, and applies equally to creep or roll. The problem here for
> you is that there is hard experimental evidence that exposes the
> position you have taken for decades, that tubular road glues are
> hopelessly flawed by a tendency to soften when heated, as complete
> and utter BS. The fact is that there *is* a difference in glues,
> and that under any but the most extreme conditions (your fabled
> descents on steep unpaved Alpine roads with constant braking to
> avoid having the bike slide out on switchbacks) this difference is
> demonstrably significant. Furthermore, there is no evidence that
> even under your extreme-beyond-reality-for-99.99%-of-people (the
> roads in your scenario were paved decades ago and if they're not
> they're properly ridden now on MTBs) scenario that Vittoria glue
> would be inadequate.
You speak as a newcomer with no experience of the subject. If you are
as sure as you seem to be about this subject, how about presenting
what you have discovered about riding tubulars under limiting
conditions? I rode those years with many riders, locally and on tours
in the Sierra and Alps. No one rolled tires but they exploded them
from tire creep as the glue melted and the tire advanced around the
rim such that the valve stem was ripped from the tube. That was the
primary failure from hot glue. Tires creep every time the brakes are
applied and it is not a go-no-go event such as rolling a tire.
>> Worse yet is the assumption that this is a linear function of
>> adhesion vs. temperature with almost no data in the graph.
> No one makes that assumption. There is test evidence to show that
> there is a difference in glues; the author explains also why they
> think the temperature that they tested to is meaningful.
The assumption is glaring in the graph of that article because there
is practically no data while straight lines are shown to fit that
meager data. Those lines could be almost anywhere and they don't go
through the points.
> If you have other hard evidence involving a thermometer and a survey
> of the conditions that people are likely to encounter that suggests
> that higher temperatures are commonplace in mountain descents,
> please present it. The fact that you got snow to sizzle on your
> wheels 40 years ago on unpaved Alpine roads does not provide such
> evidence.
Oh? I see, the boiling point of water has probably also changed in
your estimation. The point is that this is a typical descent of which
we have many right here in the Santa Cruz Mountains except that I
never had the opportunity to descend them with water in the rim.
>> This rings of so much "bench racing". Don't bet your safety on
>> this "research".
> What do you bet your safety on, then? Their research is well done.
That is your opinion. I don't share that and, as a research engineer,
have developed a record on which I can rely and believe without acts
of faith but rather on repeatable practical experience.
> Here's an idea: next time anyone wants to test their rim temperature
> after a descent{ squirt your water bottle on the rim and see if the
> water boils off. If it does, you have matched the extreme conditions
> that Brandt managed to create; otherwise, you're more in the realm of
> everyday reality tested by the researcher.
I see you don't read well either. It is surprising how fast rims cool
on such descents and, of course, that is why rim brakes work as
well as they do. I suppose you have also never blown a tire off a
clincher rim from braking heat and don't believe that occurs. I think
you need to talk to tandem riders about that.
>> You'll not that rim glue turns dark grey with use as it abrades the
>> aluminum rim. In fact the base tape wears through the anodizing if
>> that surface is anodized. Non-anodized rims develop cloth pattern
>> more rapidly in the contact surface from base tape motion without
>> descending under hard braking.
> Irrelevant to this discussion, and probably not universally true.
> Certainly not tested under any kind of controlled conditions, and
> not my recent experience.
There you go again: "probably not universally true" trying to convince
readers that you don't ride tubulars, or at least not much. I'm sure
if you visit a bicycle shop like Peter Chisholm's where you can witness
abraded aluminum surfaces of tubular rims.
Why do you insist on hypothetically arguing this subject about which,
by your own words, you have no experience.
Jobst Brandt
joseph.sa...@gmail.com
SocSecTr...@earthlink.net wrote:
<snip>
> What do you bet your safety on, then? Their research is well done.
> Here's an idea: next time anyone wants to test their rim temperature
> after a descent{ squirt your water bottle on the rim and see if the
> water boils off. If it does, you have matched the extreme conditions
> that Brandt managed to create; otherwise, you're more in the realm of
> everyday reality tested by the researcher.
</snip>
That is exactly as I have done many, many times. As I posted earlier
(perhaps in a differnt thread...) when I lived in Switzerland, I
routinely carried 2 water bottles; one for me, and one for the rims.
Squirting water onto the rims and seeing steam was a regular
occurrence. The only thing extreme about the situation was that I was
100kg and trying to keep myself from reaching terminal velocity in
free-fall off a cliff! Squirting was not done after the descent, rather
during to try to control the melt-down.
If the melt was severe and the creep got so bad that I could feel the
bump caused by the valve being forced at an angle, I would stop and
swap the wheel so it would creep back. This was not practical with the
back wheel, and since it only creeped a bit, it was enough to just pull
off the rear tire every few days and stick it back on where it was
supposed to be.
Joseph
PK
<joseph.sa...@gmail.com> wrote in message
news:1136126481....@g14g2000cwa.googlegroups.com...
> Howdy,
>
> I am considering going back to tubulars, but one of the issues that was
> most problematic for me using them in the past was the glue melting
> during heavy braking. I weigh 95-100 kg so it doesn't take too much
> breaking to get generate lots of heat, and the braking forces are high
> too, so the tires slide around on the rim a lot. This is not good. I
> used 3M Fast Tack for a while but it seemed to kill the base tapes. I
> haven't had to use glue for many years now.
>
> So what is the story with tubular glue these days? What suggestions do
> folks have for solutions to the melting problem?
>
> Joseph
>
Joseph look what you have stated in this thread fellow cyclists sniping at
one another, well some are.
I do like riding sprints and tubs I glue them using Jantex competition 76 de
lux adhesive rim tape its clean to use comes away with the tub leaving the
rim clean no problems in the wet I have never had one come off nor have I
suffered creep.
I use sprints and tubs on some of my lightweight bikes only, my audax, light
touring, expedition touring,trike, tandems, moultons roadsters and some
lightweights have clinchers.
So I hope this helps in your decision.
PK
Michael Press
<1136289523.2...@z14g2000cwz.googlegroups.com>,
SocSecTr...@earthlink.net wrote:
> You have no hard evidence of that. Get a thermometer, and then tell us
> what the temperature is. However, it is clear from the test that there
> are temperatures where some glues, 3M for instance, are significantly
> weakened, and Vittoria is completely safe.
Apply a thin layer of glue to foil, and allow to cure to
your specifications. Warm a household iron to various
temperatures and lay the unglued surface of the foil on
the iron. Repeat with different glues and temperatures.
Put different glues on the same foil and do side by side
comparisons.
--
Michael Press
Michael Press
A Muzi <a...@yellowjersey.org> wrote:
Most folks rarely corner at the very limit. When I first
was on tubulars with no experience I rolled a tire at ~15
km/hr on a very tight turn. I had not glued the tire.
But remember that it is not primarily the glue that holds
the tire. Think of a short cylinder woven of straw about
2-3 cm in diameter. Put your fingers in the cylinder, and
pull. The cylinder tries to extend and the circumference
of the cylinder tries to contract.
The cords are laid on a diagonal to the axes of the tire.
At any point on the surface of the tire the air pressure
and the curvature of the tire produce a resultant force to
stretch the tire. The resultant force is proportional to
the curvature of the surface, and therefore the force to
expand the tire along the circumference of the small
circle is greater than the force to expand the tire along
the circumference of the large circle. As the tire expands
along the small circle the angle of the bias laid cords
changes and the tire actually tries to shorten the length
of the circumference of the large circle, forcing the tire
radially into the rim.
All this applies to clincher tires as well. All bias ply
tires contract radially when inflated.
The experiment is easy. Put an unglued tubular tire on an
unglued rim, inflate, then attempt to remove it.
--
Michael Press
John Forrest Tomlinson
>
>John Forrest Tomlinson wrote:
>> On 3 Jan 2006 00:24:48 -0800, joseph.sa...@gmail.com wrote:
>>
>> >
>> >Do you know of anyone who has tried the Schwalbe Stelvio 700x25
>> >tubulars?
>>
>> I got a deal on Schwalbe stuff and got some of their tubulars in the
>> size narrower than that. Haven't used them yet, but they appear
>> well-constructed. The 700x25 are the same other than size, I think,
>> so if I can remember I'll report on the tires in April or May when I
>> use them.
>Any chance you could pump one up and measure it's width? If it has an
>actual width of 22, ther eis reason to belive the 25's will actually be
>25. If so I may be inclined to order some.
They are 22mm or maybe a little less or more -- my eyesight is not
great and don't have calipers handy. But very close.
But really, I just don't think you should be using tubulars for
everyday use -- get a frame that'll fit big fat road clinchers.
SocSecTr...@earthlink.net
jobst....@stanfordalumni.org wrote:
> > It is reasonable to suppose that if the glue is resistant to
> > softening and allowing it to roll off, it would be resistant to
> > softening in a way that would allow it to creep around the tire. In
> > fact, it is completely absurd and grasping at straws to suggest
> > otherwise. The fact remains that there is a significant dfference
> > among glues in heat resistance.
>
> Oh oh! Here is another hypothesizer speaking from the KBD rather than
> actual use of tubulars. "It is reasonable to suppose " is not a
> convincing testimony of fact. Of course there are no facts, it's all
> opinion in your perspective.
I'm not hypothisizing, I am extrapolating from test results to the real
world, the same as what you do when you endlessly tell us how your
Avocet tests on a test device prove that tubulars ridden on asphalt
have worse RR than clinchers. You don't like it? Than stop it.
> I see you also are a recent visitor here. In many of these "tubulars
> are better" threads I explained where that was "researched" as I
> descended The Nufenen Pass in the Alps after stream crossings and snow
> riding only to believe I had a flat as the tire hissed on entry into
> hairpin turns, but stopped "leaking" as soon as I let up on the
> brakes. When the tire did not go flat I discovered upon stopping,
> that steam was coming out of the stem hole. That settles the question
> for me.
I guess I would have thought you able to know the difference between
anecdote and research.
> Can you explain why "Vittoria is completely safe"? What is
> "completely safe" anyway, there being no evidence of that in the
> report.
It is an attempt to summarize the test results that show Vittoria to
retain considerable strength at 60oC, based on the assumption that the
strength of 3M at 27o is also safe, and since strength of 3M@27o =
strength of Vittoria@60o, Vittoria is safe at 60o. Are you really so
dense that you cannot fill in the omitted steps yourself?
> Just the same, thanks for defining experiments that I should do to
> support your claims of advancing glue technology. I spent many years
> riding tubulars and am fully familiar with their feet of clay as well
> as their strong points.
Yes, we know. Your anecdotes are well documented here. Your hard data
is quite sparse, though.
> You speak as a newcomer with no experience of the subject. If you are
> as sure as you seem to be about this subject, how about presenting
> what you have discovered about riding tubulars under limiting
> conditions?
We all have our anecdotes, but when it comes to hard data, the papers I
referenced trump anecdote. You have some hard data about temperatures
commonly attained in Alpine descents and glue strength, how about
presenting *it* ?
> > No one makes that assumption. There is test evidence to show that
> > there is a difference in glues; the author explains also why they
> > think the temperature that they tested to is meaningful.
>
> The assumption is glaring in the graph of that article because there
> is practically no data while straight lines are shown to fit that
> meager data. Those lines could be almost anywhere and they don't go
> through the points.
No one knows what happens over 60o, but only a liar would try to argue
that we need data points between 27o and 60o WRT Vittoria- it's safe at
27 and it's safe at 60; we know it's safe at all temperatures in
between.
> > If you have other hard evidence involving a thermometer and a survey
> > of the conditions that people are likely to encounter that suggests
> > that higher temperatures are commonplace in mountain descents,
> > please present it. The fact that you got snow to sizzle on your
> > wheels 40 years ago on unpaved Alpine roads does not provide such
> > evidence.
>
> Oh? I see, the boiling point of water has probably also changed in
> your estimation.
Well, of course it does change. We don't know the altitude at which you
noted said sizzle, therefore the boiling point of water is a
significant undefined variable. But the real point I was trying to make
is that noting water sizzling on your wheel does not provide the
slightest shred of evidence that such sizzling would be commonplace in
descents. You admitted in this ng that the circumstance was descending
on high altitude unpaved Alpine roads. That is an extreme situation
beyond the experience of of the great majority of tubular riders.
> The point is that this is a typical descent of which
> we have many right here in the Santa Cruz Mountains except that I
> never had the opportunity to descend them with water in the rim.
Unpaved? Get an MTB! But don't tell us that making a ride like that on
tubulars is proof that tubulars are unsafe on normal mountain roads.
> > What do you bet your safety on, then? Their research is well done.
>
> That is your opinion. I don't share that and, as a research engineer,
> have developed a record on which I can rely and believe without acts
> of faith but rather on repeatable practical experience.
So you are trumpeting anecdote (experience) over research, then. I have
no doubt that it is possible to melt the glue of a tubular rim if that
is your purpose, just as I have no doubt that it would be possible to
blow up a clincher from overheating of a rim if I was trying to prove
that it was possible. But taking such extreme situations and using them
as evidence that you can't use either tubulars or clinchers safely in
descents is absurd.
> > Here's an idea: next time anyone wants to test their rim temperature
> > after a descent{ squirt your water bottle on the rim and see if the
> > water boils off. If it does, you have matched the extreme conditions
> > that Brandt managed to create; otherwise, you're more in the realm of
> > everyday reality tested by the researcher.
>
> I see you don't read well either. It is surprising how fast rims cool
> on such descents and, of course, that is why rim brakes work as
> well as they do. I suppose you have also never blown a tire off a
> clincher rim from braking heat and don't believe that occurs. I think
> you need to talk to tandem riders about that.
See above, but you're right, I have never done that.
> >> You'll not that rim glue turns dark grey with use as it abrades the
> >> aluminum rim. In fact the base tape wears through the anodizing if
> >> that surface is anodized. Non-anodized rims develop cloth pattern
> >> more rapidly in the contact surface from base tape motion without
> >> descending under hard braking.
>
> > Irrelevant to this discussion, and probably not universally true.
> > Certainly not tested under any kind of controlled conditions, and
> > not my recent experience.
>
> There you go again: "probably not universally true" trying to convince
> readers that you don't ride tubulars, or at least not much. I'm sure
> if you visit a bicycle shop like Peter Chisholm's where you can witness
> abraded aluminum surfaces of tubular rims.
I have seen them in the past (although I didn't realize it at the time)
but I don't see them now on the wheels I use. I don't know why that is
so I will not try to tell you that I do. But I can technically modify
my statement to say "is certainly not universally true" because it is
not true for me in my recent cycling.
> Why do you insist on hypothetically arguing this subject about which,
> by your own words, you have no experience.
Your most recent experience riding tubulars is 30 years ago; mine is
the day before yesterday. Everyone on this ng knows that you haven't
ridden tubulars in years, but I don't really care whether anyone thinks
I do or not. The question is "Heat resistant tubular glue?" The answer
is not based on my anecdotes of riding in Germany 30 years ago, it is
based on scientific data that is absolutely current.
SocSecTr...@earthlink.net
Michael Press wrote:
> The experiment is easy. Put an unglued tubular tire on an
> unglued rim, inflate, then attempt to remove it.
Easy enough. Try the converse: try to pull a Vittoria-glued tire
without any air in it off a rim. It will be harder than your
experiment, or the tire isn't glued down properly.
Contrary to Brandt's claim, inflation is *not* the primary force
holding the tire on the rim, or shouldn't be, at least.
SocSecTr...@earthlink.net
joseph.sa...@gmail.com wrote:
> SocSecTr...@earthlink.net wrote:
> <snip>
>
> > What do you bet your safety on, then? Their research is well done.
> > Here's an idea: next time anyone wants to test their rim temperature
> > after a descent{ squirt your water bottle on the rim and see if the
> > water boils off. If it does, you have matched the extreme conditions
> > that Brandt managed to create; otherwise, you're more in the realm of
> > everyday reality tested by the researcher.
> </snip>
>
> That is exactly as I have done many, many times. As I posted earlier
> (perhaps in a differnt thread...) when I lived in Switzerland, I
> routinely carried 2 water bottles; one for me, and one for the rims.
> Squirting water onto the rims and seeing steam was a regular
> occurrence.
Seeing "steam" is not evidence of boiling. Water in a true gaseous form
is an invisible gas. I take Brandt at his word that the snow was
boiling off his rim because it was hissing, but evaporation rate
increases proportionately to temperature. The boiling point is simply
the hottest temperature at which water can still exist in liquid form
(for a given pressure, which changes significantly with altitude).
Still, I believe you that it was hot, and you bring up a good point
that I hadn't really thought about, that weight could add to the
extremity of the rim heating. If you look at the study I referenced you
will notice that some of the glues basically cease to work at the same
temp where Vittoria still provides considerable strength. The question
is, how hot were your rims, really? If you were using any other glue
besides Vittoria, that may give you a clue, because you have some idea
of how much the tire rotated under given conditions. From your
description, it sounds like you did not always reach the point where
you had to stop and flip the wheel over. Is it possible that 100%
better bond strength under the same conditions would have been enough?
It might be worth it to compare the tested performance of your glue to
Vittoria and see whether there is an indication that it might help your
situation.
jobst....@stanfordalumni.org
>>> It is reasonable to suppose that if the glue is resistant to
>>> softening and allowing it to roll off, it would be resistant to
>>> softening in a way that would allow it to creep around the
>>> tire. In fact, it is completely absurd and grasping at straws to
>>> suggest otherwise. The fact remains that there is a significant
>>> dfference among glues in heat resistance.
>> Oh oh! Here is another hypothesizer speaking from the KBD rather
>> than actual use of tubulars. "It is reasonable to suppose " is not
>> a convincing testimony of fact. Of course there are no facts, it's
>> all opinion in your perspective.
> I'm not hypothisizing, I am extrapolating from test results to the
> real world, the same as what you do when you endlessly tell us how
> your Avocet tests on a test device prove that tubulars ridden on
> asphalt have worse RR than clinchers. You don't like it? Than stop
> it.
Extrapolation in this event is purely hypothesis since you are
extrapolating extrapolated data that does not fit a curve.
>> I see you also are a recent visitor here. In many of these
>> "tubulars are better" threads I explained where that was
>> "researched" as I descended The Nufenen Pass in the Alps after
>> stream crossings and snow riding only to believe I had a flat as
>> the tire hissed on entry into hairpin turns, but stopped "leaking"
>> as soon as I let up on the brakes. When the tire did not go flat I
>> discovered upon stopping, that steam was coming out of the stem
>> hole. That settles the question for me.
> I guess I would have thought you able to know the difference between
> anecdote and research.
It depends on how the experiment is done and who does it. Being aware
of the parameters involved and the relationship between generating
bursts of steam and not doing so on hard and light braking is better
research than test stands in a laboratory, especially if the observer
is aware of the physics involved.
>> Can you explain why "Vittoria is completely safe"? What is
>> "completely safe" anyway, there being no evidence of that in the
>> report.
> It is an attempt to summarize the test results that show Vittoria to
> retain considerable strength at 60oC, based on the assumption that
> the strength of 3M at 27o is also safe, and since strength of 3M@27o
> = strength of Vittoria@60o, Vittoria is safe at 60o. Are you really
> so dense that you cannot fill in the omitted steps yourself?
You have no indication of whether the glue would allow tire creep on a
descent. That occurs long before you can lift the tire from the rim
when glue softens. As I said, these folks have no experience in the
matter they are trying to define and missed the appropriate test
method. Tires rolling off rims is not the critical mode of failure,
but rather valve stem separation as the tire creeps on the rim.
>> Just the same, thanks for defining experiments that I should do to
>> support your claims of advancing glue technology. I spent many
>> years riding tubulars and am fully familiar with their feet of clay
>> as well as their strong points.
> Yes, we know. Your anecdotes are well documented here. Your hard
> data is quite sparse, though.
Watch out, you can overuse disparaging words. I see your word of the
day is anecdote. Don't wear it out.
>> You speak as a newcomer with no experience of the subject. If you
>> are as sure as you seem to be about this subject, how about
>> presenting what you have discovered about riding tubulars under
>> limiting conditions?
> We all have our anecdotes, but when it comes to hard data, the papers I
> referenced trump anecdote. You have some hard data about temperatures
> commonly attained in Alpine descents and glue strength, how about
> presenting *it* ?
How hard must the data be. I have sheared off about six or eight
valve stems and blown four clinchers off the rim from brake heating.
Besides that, people with whom I have ridden had similar incidents.
On the 9other hand you keep referring to a bench test that tried to
place some numerical value on pull-off force that is not the critical
parameter.
>>> No one makes that assumption. There is test evidence to show that
>>> there is a difference in glues; the author explains also why they
>>> think the temperature that they tested to is meaningful.
>> The assumption is glaring in the graph of that article because
>> there is practically no data while straight lines are shown to fit
>> that meager data. Those lines could be almost anywhere and they
>> don't go through the points.
> No one knows what happens over 60o, but only a liar would try to argue
> that we need data points between 27o and 60o WRT Vittoria- it's safe at
> 27 and it's safe at 60; we know it's safe at all temperatures in
> between.
I see you are grasping for straws as you allude to lies. How is it
that these technical discussions end in rude name calling. I see no
evidence that you have unearthed in your riding that makes any of your
claims more than conjecture. I have my road tests and results that
you prefer to ignore and call anecdotes.
>>> If you have other hard evidence involving a thermometer and a
>>> survey of the conditions that people are likely to encounter that
>>> suggests that higher temperatures are commonplace in mountain
>>> descents, please present it. The fact that you got snow to sizzle
>>> on your wheels 40 years ago on unpaved Alpine roads does not
>>> provide such evidence.
>> Oh? I see, the boiling point of water has probably also changed in
>> your estimation.
> Well, of course it does change. We don't know the altitude at which
> you noted said sizzle, therefore the boiling point of water is a
> significant undefined variable. But the real point I was trying to
> make is that noting water sizzling on your wheel does not provide
> the slightest shred of evidence that such sizzling would be
> commonplace in descents. You admitted in this ng that the
> circumstance was descending on high altitude unpaved Alpine roads.
> That is an extreme situation beyond the experience of of the great
> majority of tubular riders.
I think you don't understand steam generation. It is more than sizzle
and the heat of vaporization is enough to raise the temperature of a
rim substantially above 100 degrees C in the absence of steam
generation. Are you aware of heat of vaporization?
http://www.physchem.co.za/Heat/Latent.htm
>> The point is that this is a typical descent of which we have many
>> right here in the Santa Cruz Mountains except that I never had the
>> opportunity to descend them with water in the rim.
> Unpaved? Get an MTB! But don't tell us that making a ride like
> that on tubulars is proof that tubulars are unsafe on normal
> mountain roads.
I don't know where you get that but these effects were experienced
primarily on paved roads. Paved or unpaved has no effect on rim glue
although the curves and road surface affect how fast one can let the
bicycle roll. Typically, steep paved roads such as the ones in this
area and on the Sierra like Old Priest Grade, melt rim glue regardless
of the weight or skill of the rider.
>>> What do you bet your safety on, then? Their research is well done.
>> That is your opinion. I don't share that and, as a research
>> engineer, have developed a record on which I can rely and believe
>> without acts of faith but rather on repeatable practical
>> experience.
> So you are trumpeting anecdote (experience) over research, then. I
> have no doubt that it is possible to melt the glue of a tubular rim
> if that is your purpose, just as I have no doubt that it would be
> possible to blow up a clincher from overheating of a rim if I was
> trying to prove that it was possible. But taking such extreme
> situations and using them as evidence that you can't use either
> tubulars or clinchers safely in descents is absurd.
"Trumpeting" is see your position less assured as you grasp and
ridicule to support your point of view.
You may call this anecdote but you ignore the irrefutable evidence my
observations reveal and that they are good and reliable
characterization of physical phenomena that affect the safety of
tubular tires. Not all research is done in lab coats and indoors. If
you prefer to have someone in a laboratory with a thermometer to tell
you that tubular rim glue presents no problems with respect to braking
heat, that is your prerogative. I don't see that you should lend it
any endorsement if you haven't tried it on the road to see if the test
data has any relation to performance.
It would be good if you could explain what changed since then and why
you believe that all the problems with tubulars have been solved in a
time when they are no longer used by most riders.
Jobst Brandt
jobst....@stanfordalumni.org
Well... make up your mind, which way is it. You may have given tire
creep on a hot rim some thought. If constriction from inflation
pressure weren't holding the tire in place, then it would creep off
sideways in a longer curve.
The equations for constriction forces can be found in "the Bicycle
Wheel" because these also effect spoke tension slightly.
On the other hand, if you looked at the geometry, you would see that
even at 45 degrees lean angle to the road, the center of pressure
still lies within the bed of the rim and does not tend to roll off.
As I mentioned, this mathematical analysis arose after a rider had
changed to a "dry" spare tire after a flat and descended a road while
leaning hard into turns. When arriving home, the spare was
effortlessly removed to be replaced later by a new and well glued
tire. There was no glue holding the tire in place.
Jobst Brandt
Johnny Sunset
Qui si parla Campagnolo wrote:
> Sheldon Brown wrote:
> > Peter Chisholm scritta:
> >
> > > Don't ask Jobst for any advise about tubulars. He hates them and those
> > > that use them.
> >
> > That's uncalled for. He may not like tubulars, but there's no reason to
> > accuse him of hating those who use them.
>
> Responses to me from Jobst, unlike your responses, have always been
> rude, surly, condesending. I can only surmise he has a personal problem
> with users of tubies, Delta brakes, tied and soldered wheel users.
Jobst is Jobst. I suggest learning to appreciate his style.
> ...Great. I don't sell Avocet....
That is too bad, since I have found Avocet smooth tread tires to be of
excellent quality, have better than average wet traction and
durability, and reasonably puncture resistant.
> ...some don't want to reach for their shifters....
That is why I by preference use Dura-Ace bar-end and twist-grip
shifters.
--
Tom Sherman - Fox River Valley
Ted Bennett
Peter, I wrote none of that. Please be careful with your attributions.
--
Ted Bennett
Johnny Sunset
joseph.sa...@gmail.com wrote:
> ... As I posted earlier
> (perhaps in a differnt thread...) when I lived in Switzerland, I
> routinely carried 2 water bottles; one for me, and one for the rims.
> Squirting water onto the rims and seeing steam was a regular
I hate to think how the contents of the first bottle ended up cooling
the rim!
> The only thing extreme about the situation was that I was
> 100kg and trying to keep myself from reaching terminal velocity in
> free-fall off a cliff! Squirting was not done after the descent, rather
> during to try to control the melt-down.
I hate to think how the contents of the first bottle ended up cooling
the rim!
Your mass is not that much greater than Jobst Brandt's estimated 85-90
kg [1]
[1] Based on previous posts by Jobst Brandt.
joseph.sa...@gmail.com
John Forrest Tomlinson wrote:
> On 3 Jan 2006 11:35:02 -0800, joseph.sa...@gmail.com wrote:
>
> >
> >John Forrest Tomlinson wrote:
> >> On 3 Jan 2006 00:24:48 -0800, joseph.sa...@gmail.com wrote:
> >>
> >> >
> >> >Do you know of anyone who has tried the Schwalbe Stelvio 700x25
> >> >tubulars?
> >>
> >> I got a deal on Schwalbe stuff and got some of their tubulars in the
> >> size narrower than that. Haven't used them yet, but they appear
> >> well-constructed. The 700x25 are the same other than size, I think,
> >> so if I can remember I'll report on the tires in April or May when I
> >> use them.
>
> >Any chance you could pump one up and measure it's width? If it has an
> >actual width of 22, ther eis reason to belive the 25's will actually be
> >25. If so I may be inclined to order some.
>
> They are 22mm or maybe a little less or more -- my eyesight is not
> great and don't have calipers handy. But very close.
>
> But really, I just don't think you should be using tubulars for
> everyday use -- get a frame that'll fit big fat road clinchers.
>
Thanks for measuring them. I just got a new frame. If I could find some
nice 25's that are actually 25's and not 28's, and get some stiff
wheels, I'll be fine.
Joseph
A Muzi
>>-snip-
>>> It's possible that other brands of cement have also changed
>>>in the last couple of decades. Certainly there was stuff in common
>>>use 15 or 20 years ago that almost no one I know would dare to use
>>>today -- like Tubasti.
> A Muzi <a...@yellowjersey.org> wrote:
>>I hear you. Although I also used Tubasti exclusively for
>>about 15 years, I sure wouldn't now. Some Tubasti tubes are
>>like tapioca (yes, lumpy) and some like heavy cream. Clear
>>cements are consistent - much better for achieving a thin
>>even edge-to-edge layer. Although I can't say I ever saw a
>>Tubasti-ed tire lift because of it, ya gotta wonder. . .
>>
>>As another contributor mentioned recently it is not rocket
>>science to mount a tubular on a rim. _Somebody_ is buying
>>all that Tubasti, yet we don't see a rash of lifted tires.
Michael Press wrote:
> Most folks rarely corner at the very limit. When I first
> was on tubulars with no experience I rolled a tire at ~15
> km/hr on a very tight turn. I had not glued the tire.
> But remember that it is not primarily the glue that holds
> the tire. Think of a short cylinder woven of straw about
-snip-
> The experiment is easy. Put an unglued tubular tire on an
> unglued rim, inflate, then attempt to remove it.
Yes, that's right - it's the exact test we saw conducted by
the ABL guys before every race back in prehistory. And they
yanked a few guys off the line for unsafe tubs too.
But we weren't talking about gross negligence, rather the
general usefulness, safety, suitability of tubulars [about
which no one ever changes his/her mind despite a lot of
verbiage]
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
SocSecTr...@earthlink.net
jobst....@stanfordalumni.org wrote:
> anonymous snipes:
>
> >> The experiment is easy. Put an unglued tubular tire on an unglued
> >> rim, inflate, then attempt to remove it.
>
> > Easy enough. Try the converse: try to pull a Vittoria-glued tire
> > without any air in it off a rim. It will be harder than your
> > experiment, or the tire isn't glued down properly.
>
> > Contrary to Brandt's claim, inflation is *not* the primary force
> > holding the tire on the rim, or shouldn't be, at least.
>
> Well... make up your mind, which way is it. You may have given tire
> creep on a hot rim some thought. If constriction from inflation
> pressure weren't holding the tire in place, then it would creep off
> sideways in a longer curve.
I have been consistent about this. I didn't say constriction doesn't
hold the tire in place; what I have consistently said is that with a
properly glued tire with a superior glue, the glue provides more of the
strength than inflation constriction. I know that I can roll an
inflated tire off a rim with my bare hands; I also know that it is
almost impossible for me to get a tire glued on with Vittoria off
without a lever after a flat. This corresponds to the claim in the
research that glue provides 60% of the strength. Obviously, this would
vary greatly with the glue used since Vittoria is twice as strong as
some of the other glues tested and with weaker glues or poor mounting
inflation constriction would be stronger. Maybe your decades-ago
experience was with a weaker glue, or maybe you don't know how to glue
a tire properly, and this is on what you've been basing your claim
since then that constriction provides the majority of the clamping
force. You have stated repeatedly on this ng that the gluing has to be
weak enough to allow removal after a flat on the road, presumably
without a lever (unless you state otherwise, which you haven't to
date), which I take as an admission that when you glue on a tire it is
not as strongly glued as it should be.
Qui si parla Campagnolo
jobst....@stanfordalumni.org wrote:
> Peter Chisholm writes:
>
> >> I don't believe so. If your tires are bottoming on roads, then you
> >> are close to damaging rims and getting pinch flats anyway. I think
> >> you need a suspension bicycle if the roads are that bad. Running
> >> small soft tires is not a reasonable solution as I see it. I
> >> suspect you gained some weight since you last rode tubulars.
>
> > Hmmm. I am 200 pounds...have NEVER had a pinch flat on tubies, I use
> > 95psi...
>
> I wouldn't make much hay on that. I have riding companions that
> weigh 150 lbs who got pinch flats with tubulars.
I'm surprised you let them ride with you.
I can't imagine to
> what roads you limit your rides but occasional pinch flats are a fact
> of bicycling for active riders.
"limit my rides', 'active riders'...I rode 7000 miles last year
according to my records and I live in Colorado, not a flat state. I
have not had a pinch flat when riding tubulars for 2 decades. Your
attempt to paint me as a flat lander that rides occasionally every
third weekend or so is not accurate.
That you haven't had heating problems
> tells me that you haven't descended any twisty roads that require
> constant braking, especially steep dirt roads, where high cornering
> speeds are out of the question.
>
> > Don't ask Jobst for any advise about tubulars. He hates them and
> > those that use them. He hasn't seen or used a tubular for as long as
> > I have been using them. His knowledge is not current, on these and
> > other subjects.
>
> You say that as though something about tubulars is different today
> than when they were the mainstream of tires used by bikies. Can you
> explain what that might be and how it prevents pinch flats or rim
> heating? I hear this mantra of "tubulars are better today" without
> supporting evidence.
When's the last time you actually rode a set of tubies, when was the
last time you actually saw, touched, rode any tubular...I started when
youi stopped riding tubulars...
>
> As I see it, looking at tubulars that come across my way, they are no
> easier to repair, some of them essentially not made to be repaired and
> rim glues, as was posted here not long ago are no better than those of
> yore, especailly Fastack.
>
> Gluing tires on rims has not changed:
>
> http://www.sheldonbrown.com/brandt/mounting-tubulars.html
>
> Jobst Brandt