https://bikerumor.com/tubolight-diamana-the-fastest-mtb-tire-liner-because-of-venturi-airflow-inside-your-tires/

Huh. I learned that pressure inside a closed space is equal
on all surfaces.

https://byjus.com/physics/pascals-law-and-its-application/
--
Andrew Muzi
am@yellowjersey.org
Open every day since 1 April, 1971

On 2/15/2024 4:55 PM, AMuzi wrote:
> https://bikerumor.com/tubolight-diamana-the-fastest-mtb-tire-liner-because-of-venturi-airflow-inside-your-tires/

Wow. Lots of new, um, "science" there!

--
- Frank Krygowski

On Thu, 15 Feb 2024 15:55:01 -0600, AMuzi <am@yellowjersey.org> wrote:

>https://bikerumor.com/tubolight-diamana-the-fastest-mtb-tire-liner-because-of-venturi-airflow-inside-your-tires/
>
>Huh. I learned that pressure inside a closed space is equal
>on all surfaces.
>
>https://byjus.com/physics/pascals-law-and-its-application/

Goodness, think if you put those liners in your 19 sew-ups think how
fast you would go. Why, you might even reach "lift off" speed. :-)
--
Cheers,

John B.

On 15.02.2024 22.55, AMuzi wrote:
> https://bikerumor.com/tubolight-diamana-the-fastest-mtb-tire-liner-because-of-venturi-airflow-inside-your-tires/
>
> Huh. I learned that pressure inside a closed space is equal on all
> surfaces.
>
> https://byjus.com/physics/pascals-law-and-its-application/

True, in the steady state, which will take a finite time after
a local bump has increased the pressure there. The added pressure
will propagate into the whole volume and even out. In this case
however, it bounces back in a complex way. As you then ride on
over a level surface, it will settle down to the same pressure
in the whole volume, until the next bump.
--
Dieter Britz

On 2/15/2024 4:55 PM, AMuzi wrote:
> https://bikerumor.com/tubolight-diamana-the-fastest-mtb-tire-liner-because-of-venturi-airflow-inside-your-tires/
>
> Huh. I learned that pressure inside a closed space is equal on all
> surfaces.
>
> https://byjus.com/physics/pascals-law-and-its-application/

To be fair, Diamana are talking about the complex movement of gas in the
tire as it hits bumps an recoils, not pressure in a static vessel. I'm
not savvy enough in the area of fluid dynamics to comment, but it does
raise some intriguing technical points.

--
Add xx to reply

John B. <slocombjb@gmail.com> wrote:
> On Thu, 15 Feb 2024 15:55:01 -0600, AMuzi <am@yellowjersey.org> wrote:
>
>> https://bikerumor.com/tubolight-diamana-the-fastest-mtb-tire-liner-because-of-venturi-airflow-inside-your-tires/
>>
>> Huh. I learned that pressure inside a closed space is equal
>> on all surfaces.
>>
>> https://byjus.com/physics/pascals-law-and-its-application/
>
>
> Goodness, think if you put those liners in your 19 sew-ups think how
> fast you would go. Why, you might even reach "lift off" speed. :-)

That’s not what they’re designed for, the theory (which I’m highly
sceptical of) is that during impacts during DH MTB racing it reduces the
energy lost during impact.

Unless you’re riding the Sew ups down a rocky trail I guess?

But it seems beyond marginal gains!

Roger Merriman

On Thu Feb 15 22:07:26 2024 Frank Krygowski wrote:
> On 2/15/2024 4:55 PM, AMuzi wrote:
> > https://bikerumor.com/tubolight-diamana-the-fastest-mtb-tire-liner-because-of-venturi-airflow-inside-your-tires/
>
> Wow. Lots of new, um, "science" there!
>
> --
> - Frank Krygowski
>

Are you suggesting that it isn't science? While a racing win is meaningless in and of itself, that doesn't nullify the fact that a scientific theory whether or not it is correct is not science. It doesn't not STOP being science umntil it is positively proven to be wrong.

On 2/17/2024 11:21 AM, Tom Kunich wrote:
> On Thu Feb 15 22:07:26 2024 Frank Krygowski wrote:
>> On 2/15/2024 4:55 PM, AMuzi wrote:
>>> https://bikerumor.com/tubolight-diamana-the-fastest-mtb-tire-liner-because-of-venturi-airflow-inside-your-tires/
>>
>> Wow. Lots of new, um, "science" there!
>>
>> --
>> - Frank Krygowski
>>
>
>
> Are you suggesting that it isn't science? While a racing win is meaningless in and of itself, that doesn't nullify the fact that a scientific theory whether or not it is correct is not science. It doesn't not STOP being science umntil it is positively proven to be wrong.

While there may be actual physics, this may also be
somewhere between snake oil and perpetual motion.
--
Andrew Muzi
am@yellowjersey.org
Open every day since 1 April, 1971

On Saturday, February 17, 2024 at 9:30:01 AM UTC-8, AMuzi wrote:
> On 2/17/2024 11:21 AM, Tom Kunich wrote:
> > On Thu Feb 15 22:07:26 2024 Frank Krygowski wrote:
> >> On 2/15/2024 4:55 PM, AMuzi wrote:
> >>> https://bikerumor.com/tubolight-diamana-the-fastest-mtb-tire-liner-because-of-venturi-airflow-inside-your-tires/
> >>
> >> Wow. Lots of new, um, "science" there!
> >>
> >> --
> >> - Frank Krygowski
> >>
> >
> >
> > Are you suggesting that it isn't science? While a racing win is meaningless in and of itself, that doesn't nullify the fact that a scientific theory whether or not it is correct is not science. It doesn't not STOP being science umntil it is positively proven to be wrong.
> While there may be actual physics, this may also be
> somewhere between snake oil and perpetual motion.
> --
> Andrew Muzi
> a...@yellowjersey.org
> Open every day since 1 April, 1971

I think that you're mistaking a theory which sounds preposterous on the face of it for something that may actually have some grounding in fact. This isn't something that is impossible but more along the lines of something that probably works but so little as to be too slight to worry about. Let's remember them pretending that hiding all of the cables inside of the frame tubes gives a decrease in drag. Well, yes, in theory but in practice so little as to be not worth the bother.

On 2/17/2024 3:44 PM, Tom Kunich wrote:
> On Saturday, February 17, 2024 at 9:30:01 AM UTC-8, AMuzi wrote:
>> On 2/17/2024 11:21 AM, Tom Kunich wrote:
>>> On Thu Feb 15 22:07:26 2024 Frank Krygowski wrote:
>>>> On 2/15/2024 4:55 PM, AMuzi wrote:
>>>>> https://bikerumor.com/tubolight-diamana-the-fastest-mtb-tire-liner-because-of-venturi-airflow-inside-your-tires/
>>>>
>>>> Wow. Lots of new, um, "science" there!
>>>>
>>>> --
>>>> - Frank Krygowski
>>>>
>>>
>>>
>>> Are you suggesting that it isn't science? While a racing win is meaningless in and of itself, that doesn't nullify the fact that a scientific theory whether or not it is correct is not science. It doesn't not STOP being science umntil it is positively proven to be wrong.
>> While there may be actual physics, this may also be
>> somewhere between snake oil and perpetual motion.
>> --
>> Andrew Muzi
>> a...@yellowjersey.org
>> Open every day since 1 April, 1971
>
> I think that you're mistaking a theory which sounds preposterous on the face of it for something that may actually have some grounding in fact.

"_Some_ grounding in fact" is a useless standard for judging a product
advertisement.

--
- Frank Krygowski