Fat tire riders look like "fat heads."

On 7/5/2020 3:53 PM, Sir Ridesalot wrote:
On Sunday, 5 July 2020 13:10:07 UTC-4, Frank Krygowski wrote:
On 7/4/2020 8:21 PM, Rich wrote:
On Saturday, 4 July 2020 17:28:28 UTC-4, Andre Jute wrote:
On Saturday, July 4, 2020 at 4:21:07 AM UTC+1, Rich wrote:
Unless the stupid bike is powered, why endure that ridiculous rolling resistance?

You may be inexperienced or a troll, but I've already settled that question, he http://thorncyclesforum.co.uk/index....16360#msg16360

Andre Jute
I don't follow the fashion, I create it

PS. BTW, you're ill-informed. Low pressure balloons have a lower rolling resistance, so there is no "ridiculous rolling resistance". Where'd you ever pick up that dumb street corner myth?

You are complete wrong on this, it's not possible for a tire with a larger contact patch to have lower rolling-resistance than a small, higher inflation tire. Where did you learn physics, grade-school?
I know a lot of people on mountain bikes who switched from 2.25" tires to 1.9" to lower rolling resistance.


Assertions and "I know a guy" anecdotes without data and links don't get
much respect around here.

What do you know about mechanical hysteresis?

--
- Frank Krygowski

Yet a lot of times you use anecdotes about people you know, to try and prove a point.

“One must learn the rules so one can break them properly.� ― Adrienne
Posey

--
- Frank Krygowski

On Sun, 5 Jul 2020 22:13:14 -0400, Frank Krygowski
wrote:

On 7/5/2020 8:06 PM, AMuzi wrote:
On 7/5/2020 5:41 PM, Duane wrote:
Andre Jute wrote:
On Sunday, July 5, 2020 at 5:46:09 PM UTC+1, Jeff Liebermann wrote:
On Sat, 04 Jul 2020 19:21:20 -0700, Jeff Liebermann
wrote:

When you take the same rider and bike, and switch from slicks to
knobbies, you reduce the ground patch area.* That increases the ground
pressure, which causes the rolling resistance to increase.* That's one
reason why riding knobbies on pavement is like dragging an anchor.

I forgot to mumble something about tire pressu

"Everything You Think You Know About Bicycle Tire Pressure is Probably
Wrong"
https://www.roadbikerider.com/the-tire-pressure-revolution-by-jan-heine-d1/

Quoting:
Tire pressure has almost no effect on a tire’s speed.

If lower pressures don’t make tires slower, then you
can create wide tires with supple casings. You run
them at lower pressures, and you don’t give up any
performance on smooth roads. On rough roads, you
actually gain speed, because the tire (and you) bounce
less. And on all roads, you are more comfortable.

Conclusion
Tire pressure does not significantly affect your
bike’s rolling resistance, but the casing construction
of your tires does. This means that you can ride lower
pressures without going slower, and that wide tires
are no slower than narrow ones - as long as they have
similar casings. The fastest tires have supple casings
that consume less energy when they flex, and transmit
fewer vibrations, creating a win-win situation. These
tires roll super-fast no matter at what pressure you
run them.

So, you have a choice.* A hard stiff narrow tire at high pressure or
a soft flexible wide tire at low pressure.

I'm not surprised, Jeff. Comparing the standard and the lightweight
folding Big Apples, and the thinner T19A tubes with the standard T19
tubes for 60x622 tyres, I found the lightweight versions to be very much
more comfortable with no degradation in handling and roadholding at the
limit, and not more fragile either on my rough but tarmacced lanes.
Handling is what the tyre does that is expected in response to normal
inputs up to the margin of error, roadholding is recovery from something
extreme stupid the rider does (or the road or environment does to him)
beyond the margin of error.

It must have been a common experience, because elements of the folding
Big Apple, and especially its ultra-flexible sidewall, were then spread
throughout the Big Apple range by Schwalbe, so that the folding tyre is
no longer a separate line within the brand.

Andre Jute
A life spent on the response of wheeled vehicles is not wasted.
Sometimes
I wish I continued as a hot rodder all my life.


I tend to notice handling more than slight differences in rolling
resistance.* Granted I’m not a racer trying to milk milliseconds
from my
times.* But cornering in a tight downhill is something I care about.* My
HED wheels running 23mm conti folding tire at 90 psi are the sweet
spot for
me.* Comfortable and good handling.** Just my two cents but I find the
discussion on rolling resistance without handling considered to be a bit
useless.


+1

Except rolling resistance is quantifiable, at least to a degree.
Handling is a pretty nebulous item.

Similarly, I've been skeptical of Jan Heine's testimonies about bikes
that "plane" i.e. that have the precise degree of flexibility (not too
stiff) that allows the frame to somehow match his pedal strokes and go
faster with less effort. like a speedboat that planes over the water.

I'm not saying such a thing is impossible; but I'd like some hard
evidence "planing" exists other than his rave review. If some bikes
"plane" more than others, how can we measure it?

Likewise, if one tire "handles" better than others, how can we measure
it? Does anyone know if there is an actual metric?

Boats "plane" because they rise up out of the water and thus have far
less drag.

For a bicycle to "plane" it would require the bicycle to somehow
decrease it's "drag" in some manner to allow it to increase its speed.
Note that this can be accomplished by going from an erect position on
the bike to a "head down, over the bars" position and can be easily
demonstrated by coasting down a hill and changing one's position and
watching the speedometer :-)
--
Cheers,

John B.

Andre Jute wrote:
On Sunday, July 5, 2020 at 11:41:11 PM UTC+1, Duane wrote:
Andre Jute wrote:
On Sunday, July 5, 2020 at 5:46:09 PM UTC+1, Jeff Liebermann wrote:
On Sat, 04 Jul 2020 19:21:20 -0700, Jeff Liebermann
wrote:

When you take the same rider and bike, and switch from slicks to
knobbies, you reduce the ground patch area. That increases the ground
pressure, which causes the rolling resistance to increase. That's one
reason why riding knobbies on pavement is like dragging an anchor.

I forgot to mumble something about tire pressu

"Everything You Think You Know About Bicycle Tire Pressure is Probably
Wrong"
https://www.roadbikerider.com/the-tire-pressure-revolution-by-jan-heine-d1/
Quoting:
Tire pressure has almost no effect on a tires speed.

If lower pressures dont make tires slower, then you
can create wide tires with supple casings. You run
them at lower pressures, and you dont give up any
performance on smooth roads. On rough roads, you
actually gain speed, because the tire (and you) bounce
less. And on all roads, you are more comfortable.

Conclusion
Tire pressure does not significantly affect your
bikes rolling resistance, but the casing construction
of your tires does. This means that you can ride lower
pressures without going slower, and that wide tires
are no slower than narrow ones - as long as they have
similar casings. The fastest tires have supple casings
that consume less energy when they flex, and transmit
fewer vibrations, creating a win-win situation. These
tires roll super-fast no matter at what pressure you
run them.

So, you have a choice. A hard stiff narrow tire at high pressure or
a soft flexible wide tire at low pressure.

I'm not surprised, Jeff. Comparing the standard and the lightweight
folding Big Apples, and the thinner T19A tubes with the standard T19
tubes for 60x622 tyres, I found the lightweight versions to be very much
more comfortable with no degradation in handling and roadholding at the
limit, and not more fragile either on my rough but tarmacced lanes.
Handling is what the tyre does that is expected in response to normal
inputs up to the margin of error, roadholding is recovery from something
extreme stupid the rider does (or the road or environment does to him)
beyond the margin of error.

It must have been a common experience, because elements of the folding
Big Apple, and especially its ultra-flexible sidewall, were then spread
throughout the Big Apple range by Schwalbe, so that the folding tyre is
no longer a separate line within the brand.

Andre Jute
A life spent on the response of wheeled vehicles is not wasted. Sometimes
I wish I continued as a hot rodder all my life.


I tend to notice handling more than slight differences in rolling
resistance. Granted Im not a racer trying to milk milliseconds from my
times. But cornering in a tight downhill is something I care about. My
HED wheels running 23mm conti folding tire at 90 psi are the sweet spot for
me. Comfortable and good handling. Just my two cents but I find the
discussion on rolling resistance without handling considered to be a bit
useless.

Yes, that is why my original article at
http://thorncyclesforum.co.uk/index....16360#msg16360
considered roadholding (the mannered response of a tyre) and handling
(its tolerance for rude inputs) at some length, and then considered
comfort ahead of rolling resistance. By comparison, making a mountain out
of rolling resistance, as Rich (and of course Franki-boy) try to do,
because that is what they feel can understand from the welter of
interrelated considerations, is a juvenile descent to triviality.

All the same, I clearly put a higher value on comfort than you do, Duane.
Anyone for whom 23mm tyres at 90psi are the sweet spot must have an backside of cast iron.

Andre Jute
Tyres are horses for courses


It’s probably more to do with the bike geometry than my cast iron backside
but it’s good to have lots of choices.

For me, coming from tires narrow enough to get caught in cobblestones
running 135psi this IS comfort. And my wheels are 23 mm wide so the 23 mm
tire behaves differently than on a standard width rim. Specs on HED
wheels are available online.

I do see many new road bikes showing up with wide tires and disc brakes now
though so I guess it will become the norm.

On Monday, July 6, 2020 at 12:19:42 PM UTC+2, Duane wrote:
Andre Jute wrote:
On Sunday, July 5, 2020 at 11:41:11 PM UTC+1, Duane wrote:
Andre Jute wrote:
On Sunday, July 5, 2020 at 5:46:09 PM UTC+1, Jeff Liebermann wrote:
On Sat, 04 Jul 2020 19:21:20 -0700, Jeff Liebermann
wrote:

When you take the same rider and bike, and switch from slicks to
knobbies, you reduce the ground patch area. That increases the ground
pressure, which causes the rolling resistance to increase. That's one
reason why riding knobbies on pavement is like dragging an anchor.

I forgot to mumble something about tire pressu

"Everything You Think You Know About Bicycle Tire Pressure is Probably
Wrong"
https://www.roadbikerider.com/the-tire-pressure-revolution-by-jan-heine-d1/
Quoting:
Tire pressure has almost no effect on a tire s speed.

If lower pressures don t make tires slower, then you
can create wide tires with supple casings. You run
them at lower pressures, and you don t give up any
performance on smooth roads. On rough roads, you
actually gain speed, because the tire (and you) bounce
less. And on all roads, you are more comfortable.

Conclusion
Tire pressure does not significantly affect your
bike s rolling resistance, but the casing construction
of your tires does. This means that you can ride lower
pressures without going slower, and that wide tires
are no slower than narrow ones - as long as they have
similar casings. The fastest tires have supple casings
that consume less energy when they flex, and transmit
fewer vibrations, creating a win-win situation. These
tires roll super-fast no matter at what pressure you
run them.

So, you have a choice. A hard stiff narrow tire at high pressure or
a soft flexible wide tire at low pressure.

I'm not surprised, Jeff. Comparing the standard and the lightweight
folding Big Apples, and the thinner T19A tubes with the standard T19
tubes for 60x622 tyres, I found the lightweight versions to be very much
more comfortable with no degradation in handling and roadholding at the
limit, and not more fragile either on my rough but tarmacced lanes.
Handling is what the tyre does that is expected in response to normal
inputs up to the margin of error, roadholding is recovery from something
extreme stupid the rider does (or the road or environment does to him)
beyond the margin of error.

It must have been a common experience, because elements of the folding
Big Apple, and especially its ultra-flexible sidewall, were then spread
throughout the Big Apple range by Schwalbe, so that the folding tyre is
no longer a separate line within the brand.

Andre Jute
A life spent on the response of wheeled vehicles is not wasted. Sometimes
I wish I continued as a hot rodder all my life.


I tend to notice handling more than slight differences in rolling
resistance. Granted I m not a racer trying to milk milliseconds from my
times. But cornering in a tight downhill is something I care about. My
HED wheels running 23mm conti folding tire at 90 psi are the sweet spot for
me. Comfortable and good handling. Just my two cents but I find the
discussion on rolling resistance without handling considered to be a bit
useless.

Yes, that is why my original article at
http://thorncyclesforum.co.uk/index....16360#msg16360
considered roadholding (the mannered response of a tyre) and handling
(its tolerance for rude inputs) at some length, and then considered
comfort ahead of rolling resistance. By comparison, making a mountain out
of rolling resistance, as Rich (and of course Franki-boy) try to do,
because that is what they feel can understand from the welter of
interrelated considerations, is a juvenile descent to triviality.

All the same, I clearly put a higher value on comfort than you do, Duane.
Anyone for whom 23mm tyres at 90psi are the sweet spot must have an backside of cast iron.

Andre Jute
Tyres are horses for courses


It’s probably more to do with the bike geometry than my cast iron backside
but it’s good to have lots of choices.

For me, coming from tires narrow enough to get caught in cobblestones
running 135psi this IS comfort. And my wheels are 23 mm wide so the 23 mm
tire behaves differently than on a standard width rim. Specs on HED
wheels are available online.

I do see many new road bikes showing up with wide tires and disc brakes now
though so I guess it will become the norm.

The idea that wider tires equals comfort is false IMO. Lower pressure equals comfort. Wider tires gives you the option to run lower pressures without an increased chance of a pinch flat and at that lower pressure a better handling cornering.

Lou

On 7/6/2020 2:02 AM, John B. wrote:
On Sun, 5 Jul 2020 22:13:14 -0400, Frank Krygowski
wrote:

On 7/5/2020 8:06 PM, AMuzi wrote:
On 7/5/2020 5:41 PM, Duane wrote:
Andre Jute wrote:
On Sunday, July 5, 2020 at 5:46:09 PM UTC+1, Jeff Liebermann wrote:
On Sat, 04 Jul 2020 19:21:20 -0700, Jeff Liebermann
wrote:

When you take the same rider and bike, and switch from slicks to
knobbies, you reduce the ground patch area.Â* That increases the ground
pressure, which causes the rolling resistance to increase.Â* That's one
reason why riding knobbies on pavement is like dragging an anchor.

I forgot to mumble something about tire pressu

"Everything You Think You Know About Bicycle Tire Pressure is Probably
Wrong"
https://www.roadbikerider.com/the-tire-pressure-revolution-by-jan-heine-d1/

Quoting:
Tire pressure has almost no effect on a tire’s speed.

If lower pressures don’t make tires slower, then you
can create wide tires with supple casings. You run
them at lower pressures, and you don’t give up any
performance on smooth roads. On rough roads, you
actually gain speed, because the tire (and you) bounce
less. And on all roads, you are more comfortable.

Conclusion
Tire pressure does not significantly affect your
bike’s rolling resistance, but the casing construction
of your tires does. This means that you can ride lower
pressures without going slower, and that wide tires
are no slower than narrow ones - as long as they have
similar casings. The fastest tires have supple casings
that consume less energy when they flex, and transmit
fewer vibrations, creating a win-win situation. These
tires roll super-fast no matter at what pressure you
run them.

So, you have a choice.Â* A hard stiff narrow tire at high pressure or
a soft flexible wide tire at low pressure.

I'm not surprised, Jeff. Comparing the standard and the lightweight
folding Big Apples, and the thinner T19A tubes with the standard T19
tubes for 60x622 tyres, I found the lightweight versions to be very much
more comfortable with no degradation in handling and roadholding at the
limit, and not more fragile either on my rough but tarmacced lanes.
Handling is what the tyre does that is expected in response to normal
inputs up to the margin of error, roadholding is recovery from something
extreme stupid the rider does (or the road or environment does to him)
beyond the margin of error.

It must have been a common experience, because elements of the folding
Big Apple, and especially its ultra-flexible sidewall, were then spread
throughout the Big Apple range by Schwalbe, so that the folding tyre is
no longer a separate line within the brand.

Andre Jute
A life spent on the response of wheeled vehicles is not wasted.
Sometimes
I wish I continued as a hot rodder all my life.


I tend to notice handling more than slight differences in rolling
resistance.Â* Granted I’m not a racer trying to milk milliseconds
from my
times.Â* But cornering in a tight downhill is something I care about.Â* My
HED wheels running 23mm conti folding tire at 90 psi are the sweet
spot for
me.Â* Comfortable and good handling.Â*Â* Just my two cents but I find the
discussion on rolling resistance without handling considered to be a bit
useless.


+1

Except rolling resistance is quantifiable, at least to a degree.
Handling is a pretty nebulous item.

Similarly, I've been skeptical of Jan Heine's testimonies about bikes
that "plane" i.e. that have the precise degree of flexibility (not too
stiff) that allows the frame to somehow match his pedal strokes and go
faster with less effort. like a speedboat that planes over the water.

I'm not saying such a thing is impossible; but I'd like some hard
evidence "planing" exists other than his rave review. If some bikes
"plane" more than others, how can we measure it?

Likewise, if one tire "handles" better than others, how can we measure
it? Does anyone know if there is an actual metric?

Boats "plane" because they rise up out of the water and thus have far
less drag.

For a bicycle to "plane" it would require the bicycle to somehow
decrease it's "drag" in some manner to allow it to increase its speed.
Note that this can be accomplished by going from an erect position on
the bike to a "head down, over the bars" position and can be easily
demonstrated by coasting down a hill and changing one's position and
watching the speedometer :-)

I agree. Jan Heine doesn't seem to attribute "planing" of a bike to
reduced resistance. He seems to believe that a bike frame with just the
right flexibility - not too much, not too little - somehow flexes in
synchrony with his pedal strokes and allows him to put in more power
with less fatigue.

Absent measurements and data, I'm very skeptical.


--
- Frank Krygowski

On 7/5/2020 3:41 PM, Duane wrote:
Andre Jute wrote:
On Sunday, July 5, 2020 at 5:46:09 PM UTC+1, Jeff Liebermann wrote:
On Sat, 04 Jul 2020 19:21:20 -0700, Jeff Liebermann
wrote:

When you take the same rider and bike, and switch from slicks to
knobbies, you reduce the ground patch area. That increases the ground
pressure, which causes the rolling resistance to increase. That's one
reason why riding knobbies on pavement is like dragging an anchor.

I forgot to mumble something about tire pressu

"Everything You Think You Know About Bicycle Tire Pressure is Probably
Wrong"
https://www.roadbikerider.com/the-tire-pressure-revolution-by-jan-heine-d1/
Quoting:
Tire pressure has almost no effect on a tire’s speed.

If lower pressures don’t make tires slower, then you
can create wide tires with supple casings. You run
them at lower pressures, and you don’t give up any
performance on smooth roads. On rough roads, you
actually gain speed, because the tire (and you) bounce
less. And on all roads, you are more comfortable.

Conclusion
Tire pressure does not significantly affect your
bike’s rolling resistance, but the casing construction
of your tires does. This means that you can ride lower
pressures without going slower, and that wide tires
are no slower than narrow ones - as long as they have
similar casings. The fastest tires have supple casings
that consume less energy when they flex, and transmit
fewer vibrations, creating a win-win situation. These
tires roll super-fast no matter at what pressure you
run them.

So, you have a choice. A hard stiff narrow tire at high pressure or
a soft flexible wide tire at low pressure.

I'm not surprised, Jeff. Comparing the standard and the lightweight
folding Big Apples, and the thinner T19A tubes with the standard T19
tubes for 60x622 tyres, I found the lightweight versions to be very much
more comfortable with no degradation in handling and roadholding at the
limit, and not more fragile either on my rough but tarmacced lanes.
Handling is what the tyre does that is expected in response to normal
inputs up to the margin of error, roadholding is recovery from something
extreme stupid the rider does (or the road or environment does to him)
beyond the margin of error.

It must have been a common experience, because elements of the folding
Big Apple, and especially its ultra-flexible sidewall, were then spread
throughout the Big Apple range by Schwalbe, so that the folding tyre is
no longer a separate line within the brand.

Andre Jute
A life spent on the response of wheeled vehicles is not wasted. Sometimes
I wish I continued as a hot rodder all my life.


I tend to notice handling more than slight differences in rolling
resistance. Granted I’m not a racer trying to milk milliseconds from my
times. But cornering in a tight downhill is something I care about. My
HED wheels running 23mm conti folding tire at 90 psi are the sweet spot for
me. Comfortable and good handling. Just my two cents but I find the
discussion on rolling resistance without handling considered to be a bit
useless.

For a very different perspective, yesterday I took the gravel bike out
for a spin.

On the gravel bike - on gravel - rolling resistance takes on a much more
dominant role. Handling is more of an issue than on pavement. Never
mind efficiency, a harder/narrower rear tire gives so much bouncing and
skittering side-to-side that /control/ takes a lot more effort - and I'm
talking about riding in a straight line! I've found that good side lugs
on a tire help with the skittering - feels like the tire stays on top of
pieces of gravel rather than riding up and falling off sideways.

I've written before that the gravel in my county is pretty rough, though
that seems to vary by the week. Sometimes I'll find a nice hard-pack
track down the middle of the road, but I think the county just re-spread
gravel, 'cause it was all loose stuff yesterday.

There's no doubt I'm sinking a lot more energy into rolling resistance
than on a road bike. I can even quantify it a bit, being a data junkie
and having PowerTap wheels on both road and gravel bikes. On the road,
it takes a very brisk ride to burn over about 33-34 kiloJoules per mile.
Yesterday on the gravel, at a much lower speed, I averaged 35 kJ/mile.
This is for rides that start and end at the same elevation.

It's a topic for another post, but I find on the road that energy /per
mile/ is surprisingly consistent, ranging from around 27 kJ/mile for a
gentle pootle to maybe 35 kJ/mile for a very brisk hilly ride, with most
rides in the 30-33 range. Not, of course, on rides that start and end
at different elevations.

Lower pressure helps handling/skittering with the wider contact patch.
But the lower limit of tire pressure to avoid pinch flats seems to vary
by the minute; it all depends on what you hit, so there's no rule there
even for a given tire/rim/rider. I've only pinch flat once so far in
many rides, but I think it was a fluke rock hit.

The rims on my bike - Trek Checkpoint SL 5 - are really too narrow for
my tastes, but I took too long to figure that out. The bike came with
35mm tires, quickly swapped to 42mm. The tires are so much wider than
the rim, and run around 35-37psi, that they /always/ LOOK flat, even
when they're fine. Between the bounce of intentionally soft tires and
the vertical flex designed into the frame, the tires always /feel/ a bit
flat too, enough that I sometimes stop and check.

It's a good question what pressure I'd use on a comfort-be-damned
go-as-fast-as-possible ride, since I'm doing this for fun and I haven't
raced in many years.

Mark J.

On Monday, July 6, 2020 at 7:15:32 PM UTC+2, Mark J. wrote:



It's a topic for another post, but I find on the road that energy /per
mile/ is surprisingly consistent, ranging from around 27 kJ/mile for a
gentle pootle to maybe 35 kJ/mile for a very brisk hilly ride, with most
rides in the 30-33 range. Not, of course, on rides that start and end
at different elevations.


Tell that to the people that say that 10-20 Watt on average is insignificant.

Lou

On Monday, 6 July 2020 13:15:32 UTC-4, Mark J. wrote:
On 7/5/2020 3:41 PM, Duane wrote:
Andre Jute wrote:
On Sunday, July 5, 2020 at 5:46:09 PM UTC+1, Jeff Liebermann wrote:
On Sat, 04 Jul 2020 19:21:20 -0700, Jeff Liebermann
wrote:

When you take the same rider and bike, and switch from slicks to
knobbies, you reduce the ground patch area. That increases the ground
pressure, which causes the rolling resistance to increase. That's one
reason why riding knobbies on pavement is like dragging an anchor.

I forgot to mumble something about tire pressu

"Everything You Think You Know About Bicycle Tire Pressure is Probably
Wrong"
https://www.roadbikerider.com/the-tire-pressure-revolution-by-jan-heine-d1/
Quoting:
Tire pressure has almost no effect on a tire’s speed.

If lower pressures don’t make tires slower, then you
can create wide tires with supple casings. You run
them at lower pressures, and you don’t give up any
performance on smooth roads. On rough roads, you
actually gain speed, because the tire (and you) bounce
less. And on all roads, you are more comfortable.

Conclusion
Tire pressure does not significantly affect your
bike’s rolling resistance, but the casing construction
of your tires does. This means that you can ride lower
pressures without going slower, and that wide tires
are no slower than narrow ones - as long as they have
similar casings. The fastest tires have supple casings
that consume less energy when they flex, and transmit
fewer vibrations, creating a win-win situation. These
tires roll super-fast no matter at what pressure you
run them.

So, you have a choice. A hard stiff narrow tire at high pressure or
a soft flexible wide tire at low pressure.

I'm not surprised, Jeff. Comparing the standard and the lightweight
folding Big Apples, and the thinner T19A tubes with the standard T19
tubes for 60x622 tyres, I found the lightweight versions to be very much
more comfortable with no degradation in handling and roadholding at the
limit, and not more fragile either on my rough but tarmacced lanes.
Handling is what the tyre does that is expected in response to normal
inputs up to the margin of error, roadholding is recovery from something
extreme stupid the rider does (or the road or environment does to him)
beyond the margin of error.

It must have been a common experience, because elements of the folding
Big Apple, and especially its ultra-flexible sidewall, were then spread
throughout the Big Apple range by Schwalbe, so that the folding tyre is
no longer a separate line within the brand.

Andre Jute
A life spent on the response of wheeled vehicles is not wasted. Sometimes
I wish I continued as a hot rodder all my life.


I tend to notice handling more than slight differences in rolling
resistance. Granted I’m not a racer trying to milk milliseconds from my
times. But cornering in a tight downhill is something I care about. My
HED wheels running 23mm conti folding tire at 90 psi are the sweet spot for
me. Comfortable and good handling. Just my two cents but I find the
discussion on rolling resistance without handling considered to be a bit
useless.

For a very different perspective, yesterday I took the gravel bike out
for a spin.

On the gravel bike - on gravel - rolling resistance takes on a much more
dominant role. Handling is more of an issue than on pavement. Never
mind efficiency, a harder/narrower rear tire gives so much bouncing and
skittering side-to-side that /control/ takes a lot more effort - and I'm
talking about riding in a straight line! I've found that good side lugs
on a tire help with the skittering - feels like the tire stays on top of
pieces of gravel rather than riding up and falling off sideways.

I've written before that the gravel in my county is pretty rough, though
that seems to vary by the week. Sometimes I'll find a nice hard-pack
track down the middle of the road, but I think the county just re-spread
gravel, 'cause it was all loose stuff yesterday.

There's no doubt I'm sinking a lot more energy into rolling resistance
than on a road bike. I can even quantify it a bit, being a data junkie
and having PowerTap wheels on both road and gravel bikes. On the road,
it takes a very brisk ride to burn over about 33-34 kiloJoules per mile.
Yesterday on the gravel, at a much lower speed, I averaged 35 kJ/mile.
This is for rides that start and end at the same elevation.

It's a topic for another post, but I find on the road that energy /per
mile/ is surprisingly consistent, ranging from around 27 kJ/mile for a
gentle pootle to maybe 35 kJ/mile for a very brisk hilly ride, with most
rides in the 30-33 range. Not, of course, on rides that start and end
at different elevations.

Lower pressure helps handling/skittering with the wider contact patch.
But the lower limit of tire pressure to avoid pinch flats seems to vary
by the minute; it all depends on what you hit, so there's no rule there
even for a given tire/rim/rider. I've only pinch flat once so far in
many rides, but I think it was a fluke rock hit.

The rims on my bike - Trek Checkpoint SL 5 - are really too narrow for
my tastes, but I took too long to figure that out. The bike came with
35mm tires, quickly swapped to 42mm. The tires are so much wider than
the rim, and run around 35-37psi, that they /always/ LOOK flat, even
when they're fine. Between the bounce of intentionally soft tires and
the vertical flex designed into the frame, the tires always /feel/ a bit
flat too, enough that I sometimes stop and check.

It's a good question what pressure I'd use on a comfort-be-damned
go-as-fast-as-possible ride, since I'm doing this for fun and I haven't
raced in many years.

Mark J.

I remember a few years ago a ride on our MTBs when we were coming home along a dirt road. A few kilometers along after turning onto another dirt road we discovered that it had just been freshly graveled. that gravel layer was deep and loose, so much do that it was hard io ride a straight line on my rigid MTB or my friend's front suspension MTB. Both had 26" x 2.125 or 2.25 knobby tires on them. On a skinny tire it'd have been impossible to ride that stretch or road.

Cheers

On Monday, July 6, 2020 at 2:08:32 PM UTC+1, Lou Holtman wrote:
On Monday, July 6, 2020 at 12:19:42 PM UTC+2, Duane wrote:
Andre Jute wrote:
On Sunday, July 5, 2020 at 11:41:11 PM UTC+1, Duane wrote:
Andre Jute wrote:
On Sunday, July 5, 2020 at 5:46:09 PM UTC+1, Jeff Liebermann wrote:
On Sat, 04 Jul 2020 19:21:20 -0700, Jeff Liebermann
wrote:

When you take the same rider and bike, and switch from slicks to
knobbies, you reduce the ground patch area. That increases the ground
pressure, which causes the rolling resistance to increase. That's one
reason why riding knobbies on pavement is like dragging an anchor..

I forgot to mumble something about tire pressu

"Everything You Think You Know About Bicycle Tire Pressure is Probably
Wrong"
https://www.roadbikerider.com/the-tire-pressure-revolution-by-jan-heine-d1/
Quoting:
Tire pressure has almost no effect on a tire s speed.

If lower pressures don t make tires slower, then you
can create wide tires with supple casings. You run
them at lower pressures, and you don t give up any
performance on smooth roads. On rough roads, you
actually gain speed, because the tire (and you) bounce
less. And on all roads, you are more comfortable.

Conclusion
Tire pressure does not significantly affect your
bike s rolling resistance, but the casing construction
of your tires does. This means that you can ride lower
pressures without going slower, and that wide tires
are no slower than narrow ones - as long as they have
similar casings. The fastest tires have supple casings
that consume less energy when they flex, and transmit
fewer vibrations, creating a win-win situation. These
tires roll super-fast no matter at what pressure you
run them.

So, you have a choice. A hard stiff narrow tire at high pressure or
a soft flexible wide tire at low pressure.

I'm not surprised, Jeff. Comparing the standard and the lightweight
folding Big Apples, and the thinner T19A tubes with the standard T19
tubes for 60x622 tyres, I found the lightweight versions to be very much
more comfortable with no degradation in handling and roadholding at the
limit, and not more fragile either on my rough but tarmacced lanes.
Handling is what the tyre does that is expected in response to normal
inputs up to the margin of error, roadholding is recovery from something
extreme stupid the rider does (or the road or environment does to him)
beyond the margin of error.

It must have been a common experience, because elements of the folding
Big Apple, and especially its ultra-flexible sidewall, were then spread
throughout the Big Apple range by Schwalbe, so that the folding tyre is
no longer a separate line within the brand.

Andre Jute
A life spent on the response of wheeled vehicles is not wasted. Sometimes
I wish I continued as a hot rodder all my life.


I tend to notice handling more than slight differences in rolling
resistance. Granted I m not a racer trying to milk milliseconds from my
times. But cornering in a tight downhill is something I care about. My
HED wheels running 23mm conti folding tire at 90 psi are the sweet spot for
me. Comfortable and good handling. Just my two cents but I find the
discussion on rolling resistance without handling considered to be a bit
useless.

Yes, that is why my original article at
http://thorncyclesforum.co.uk/index....16360#msg16360
considered roadholding (the mannered response of a tyre) and handling
(its tolerance for rude inputs) at some length, and then considered
comfort ahead of rolling resistance. By comparison, making a mountain out
of rolling resistance, as Rich (and of course Franki-boy) try to do,
because that is what they feel can understand from the welter of
interrelated considerations, is a juvenile descent to triviality.

All the same, I clearly put a higher value on comfort than you do, Duane.
Anyone for whom 23mm tyres at 90psi are the sweet spot must have an backside of cast iron.

Andre Jute
Tyres are horses for courses


It’s probably more to do with the bike geometry than my cast iron backside
but it’s good to have lots of choices.

For me, coming from tires narrow enough to get caught in cobblestones
running 135psi this IS comfort. And my wheels are 23 mm wide so the 23 mm
tire behaves differently than on a standard width rim. Specs on HED
wheels are available online.

I do see many new road bikes showing up with wide tires and disc brakes now
though so I guess it will become the norm.

The idea that wider tires equals comfort is false IMO. Lower pressure equals comfort. Wider tires gives you the option to run lower pressures without an increased chance of a pinch flat and at that lower pressure a better handling cornering.

Lou

That's right. The link between wider tires and greater comfort isn't direct but via the possibility of lower pressure. People are always surprised after they ride my bike to discover that the comfort comes despite the reluctance of the stiff rolling surface on my Big apples to flex very much under finger pressure. But the flex is in the air against the soft sidewalls.

Andre Jute
Nothing in suspensions, automobile or bicycle, is as straightforward as one might expect

Lou Holtman wrote:
On Monday, July 6, 2020 at 12:19:42 PM UTC+2, Duane wrote:
Andre Jute wrote:
On Sunday, July 5, 2020 at 11:41:11 PM UTC+1, Duane wrote:
Andre Jute wrote:
On Sunday, July 5, 2020 at 5:46:09 PM UTC+1, Jeff Liebermann wrote:
On Sat, 04 Jul 2020 19:21:20 -0700, Jeff Liebermann
wrote:

When you take the same rider and bike, and switch from slicks to
knobbies, you reduce the ground patch area. That increases the ground
pressure, which causes the rolling resistance to increase. That's one
reason why riding knobbies on pavement is like dragging an anchor.

I forgot to mumble something about tire pressu

"Everything You Think You Know About Bicycle Tire Pressure is Probably
Wrong"
https://www.roadbikerider.com/the-tire-pressure-revolution-by-jan-heine-d1/
Quoting:
Tire pressure has almost no effect on a tire s speed.

If lower pressures don t make tires slower, then you
can create wide tires with supple casings. You run
them at lower pressures, and you don t give up any
performance on smooth roads. On rough roads, you
actually gain speed, because the tire (and you) bounce
less. And on all roads, you are more comfortable.

Conclusion
Tire pressure does not significantly affect your
bike s rolling resistance, but the casing construction
of your tires does. This means that you can ride lower
pressures without going slower, and that wide tires
are no slower than narrow ones - as long as they have
similar casings. The fastest tires have supple casings
that consume less energy when they flex, and transmit
fewer vibrations, creating a win-win situation. These
tires roll super-fast no matter at what pressure you
run them.

So, you have a choice. A hard stiff narrow tire at high pressure or
a soft flexible wide tire at low pressure.

I'm not surprised, Jeff. Comparing the standard and the lightweight
folding Big Apples, and the thinner T19A tubes with the standard T19
tubes for 60x622 tyres, I found the lightweight versions to be very much
more comfortable with no degradation in handling and roadholding at the
limit, and not more fragile either on my rough but tarmacced lanes.
Handling is what the tyre does that is expected in response to normal
inputs up to the margin of error, roadholding is recovery from something
extreme stupid the rider does (or the road or environment does to him)
beyond the margin of error.

It must have been a common experience, because elements of the folding
Big Apple, and especially its ultra-flexible sidewall, were then spread
throughout the Big Apple range by Schwalbe, so that the folding tyre is
no longer a separate line within the brand.

Andre Jute
A life spent on the response of wheeled vehicles is not wasted. Sometimes
I wish I continued as a hot rodder all my life.


I tend to notice handling more than slight differences in rolling
resistance. Granted I m not a racer trying to milk milliseconds from my
times. But cornering in a tight downhill is something I care about. My
HED wheels running 23mm conti folding tire at 90 psi are the sweet spot for
me. Comfortable and good handling. Just my two cents but I find the
discussion on rolling resistance without handling considered to be a bit
useless.

Yes, that is why my original article at
http://thorncyclesforum.co.uk/index....16360#msg16360
considered roadholding (the mannered response of a tyre) and handling
(its tolerance for rude inputs) at some length, and then considered
comfort ahead of rolling resistance. By comparison, making a mountain out
of rolling resistance, as Rich (and of course Franki-boy) try to do,
because that is what they feel can understand from the welter of
interrelated considerations, is a juvenile descent to triviality.

All the same, I clearly put a higher value on comfort than you do, Duane.
Anyone for whom 23mm tyres at 90psi are the sweet spot must have an
backside of cast iron.

Andre Jute
Tyres are horses for courses


It’s probably more to do with the bike geometry than my cast iron backside
but it’s good to have lots of choices.

For me, coming from tires narrow enough to get caught in cobblestones
running 135psi this IS comfort. And my wheels are 23 mm wide so the 23 mm
tire behaves differently than on a standard width rim. Specs on HED
wheels are available online.

I do see many new road bikes showing up with wide tires and disc brakes now
though so I guess it will become the norm.

The idea that wider tires equals comfort is false IMO. Lower pressure
equals comfort. Wider tires gives you the option to run lower pressures
without an increased chance of a pinch flat and at that lower pressure a
better handling cornering.

Lou


Agreed.