Are tubeless tires more comfortable than cotton clinchers + latex tubes?

Discuss light weight issues concerning road bikes & parts.
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TonyM
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Joined: Thu Jan 22, 2015 4:11 pm

by TonyM

That‘s where I see a main difference between people being fatigued due to high pressure in their tires, harsh frame etc...and people who don‘t have many issued with that kind of things. Like people having back issues vs people w/o. Or older people etc...

Same I see people buying aero or semi aero race bikes (i.e Dogma, Venge etc...) but having problems due the harshness of the frame or due to the low position. They should better take a „regular“ bike and enjoy their ride (and may be even faster on a 150km ride).

by Weenie


ichobi
Posts: 911
Joined: Thu Jan 19, 2012 11:30 pm

by ichobi

zefs wrote:It's a bit a contradictive though, saying that suspension losses and bouncing makes you slower, then saying lower pressures are not slower than higher pressures on smooth tarmac. If you use low enough pressures (for your weight that is) to be super comfortable, the bike will bounce when applying power on the downstroke, and the effect will increase the more downward power you apply = this sluggish feeling which is indeed slower. But then, using a comfortable pressure can lead to being faster overall since you will probably be less fatigued.
Which is why every rider who cares to get the most out or their bike should test and find their own optimal pressure. I change the pressure according to route I pick each time. When you do it often enough you are in tune with your bike to know what pressure to use for which kind of road without getting that sluggish feel or the bouncy harshy feel.

Having said that I also find it contradictory to buy an aero bike( and by virtue a harsh bike, except may be the Madone) only to find it innately harsh and trying to use 28mm tires and low pressure on it, negating the aero benefit it’s supposed to give you in the first place. I had this experience first hand with the Aeroad cf slx. A reasonably comfortable bike but can’t really handle micro bumps all that well. Shook me to the bone even with wider tires and rim and low pressure. It will never be as comfortable as my SL6 for example.

TobinHatesYou
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Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

zefs wrote:
Mon May 27, 2019 9:40 pm
It's a bit a contradictive though, saying that suspension losses and bouncing makes you slower, then saying lower pressures are not slower than higher pressures on smooth tarmac. If you use low enough pressures (for your weight that is) to be super comfortable, the bike will bounce when applying power on the downstroke, and the effect will increase the more downward power you apply = this sluggish feeling which is indeed slower. But then, using a comfortable pressure can lead to being faster overall since you will probably be less fatigued.

On a perfect surface, higher pressures are almost certainly better. See all those hour record attempts with track tubs being inflated to almost 200psi.

I don't think they're really talking about tire deformation and suspension losses here, but the tire actually bouncing off the road surface to a very small degree at higher pressures. Apparently this happens even on pretty smooth roads >100psi. Imagine two identical setups, one at 90 psi and one at 100psi. Whenever that 100psi tire ever-slightly bounces into the air during a roll-down test, that's wheel spin not being used to cover a distance.
ichobi wrote:
Mon May 27, 2019 10:17 pm

Having said that I also find it contradictory to buy an aero bike( and by virtue a harsh bike, except may be the Madone) only to find it innately harsh and trying to use 28mm tires and low pressure on it, negating the aero benefit it’s supposed to give you in the first place. I had this experience first hand with the Aeroad cf slx. A reasonably comfortable bike but can’t really handle micro bumps all that well. Shook me to the bone even with wider tires and rim and low pressure. It will never be as comfortable as my SL6 for example.

Only semi-contradictory. Flip the script and ask why pros generally don't ride 23mm tires with their aero bikes. In the end rolling resistance pales in comparison to aerodynamic drag above about 10mph. Whether you think the aero gains from a 25mm tire and rim combo are worth it...that's up to you. There's clearly puncture resistance, impact absorption benefits from running wider tires at lower pressures.
Last edited by TobinHatesYou on Mon May 27, 2019 10:29 pm, edited 1 time in total.

petromyzon
Posts: 377
Joined: Mon Apr 05, 2010 4:14 pm

by petromyzon

Jarno has tested both Turbo and Turbo cotton and found 3.3W between them. The vulcanised tyre is lighter but slower, probably because it is thicker under the tread (2.8 vs 2.1). The casing in the vulcanised tyre is thinner (0.5 vs 0.75).
I am inclined to believe that compound is king but it would be nice to see vulcanised and non-vulcanised tyres of an identical thickness and puncture barrier tested against eachother.
I like cotton tyres but I suspect that tyre pressure is the most important factor in terms of suspension losses, and compound is the most important in terms of hysteretic losses.
Conti are claiming some kind of "active comfort technology" for the 5000 and I have to say I find it much smoother than the 4000.

coresare
Posts: 102
Joined: Thu Jun 18, 2015 8:19 am

by coresare

I have Corima MCC S+ 47mm carbon spoke wheels with Vittoria Corsa CX tubulars. These wheels are super stiff so it is not apples to apples comparison with my Zipp 303 clincher with continental GP4K with Vittoria latex innertubes, but they feel about the same to me in terms of comfort. Both are using 25mm tires. The Corima wheels are only 22.6mm wide though. The Zipps are much wider.
Last edited by coresare on Tue May 28, 2019 12:57 am, edited 1 time in total.

ichobi
Posts: 911
Joined: Thu Jan 19, 2012 11:30 pm

by ichobi

petromyzon wrote:
Mon May 27, 2019 10:22 pm
I like cotton tyres but I suspect that tyre pressure is the most important factor in terms of suspension losses, and compound is the most important in terms of hysteretic losses.
In other words, the former is comfort, and the latter is speed?

TobinHatesYou
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Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

ichobi wrote:
Mon May 27, 2019 11:50 pm
petromyzon wrote:
Mon May 27, 2019 10:22 pm
I like cotton tyres but I suspect that tyre pressure is the most important factor in terms of suspension losses, and compound is the most important in terms of hysteretic losses.
In other words, the former is comfort, and the latter is speed?

Suspension losses are hysteresis losses. When a tire casing deforms and then rebounds, it is absorbing energy and then releasing it. Some energy is lost in the process. There are hysteresis losses in rubber compound deformation, but the differences are tiny. Tire compounds all fall into a narrow band on the Shore A scale. Compound differences have a larger effect on grip, durability and direct friction losses

Hexsense
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Joined: Wed Dec 30, 2015 12:41 am

by Hexsense

perhaps, we need to define separation more clearly of hysteresis losses on the tire,
and suspension loss of the bike+rider.

Rock solid tire may not have hysteresis lost. Yet we lost a lot of energy by bike+rider suspend the micro bumps.

Wait a minute, it's the rider and bike that suspend the residue vibration that tire didn't absorb.
Rider and bike are generally bad at suspension efficiency compare to tire, and compare to solid weight (which don't suspend, it reflect energy back at the tire).
Is that what static weight on wheel rolling resistance test miss? It doesn't care how good a tire work in reducing vibration, so that the rider don't have to absorb it.
Last edited by Hexsense on Tue May 28, 2019 4:34 am, edited 1 time in total.

TobinHatesYou
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Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

Hexsense wrote:
Tue May 28, 2019 4:17 am
perhaps, we need to define separation more clearly of hysteresis losses on the tire,
and suspension loss of the bike+rider.

Rock solid tire may not have hysteresis lost. Yet we lost a lot of energy by bike+rider suspend the micro bumps.

A rock solid tire will also lift (aka bounce) over road surface imperfections whereas a more supple tire will deform around it and limit the energy lost through that lift. This is effectively what happens with tires on cobbles, but on a smaller scale. Every vibration, judder, jolt is energy not being used to move you forward.

Hexsense
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Joined: Wed Dec 30, 2015 12:41 am

by Hexsense

If the bump is truely micro, rider and bike are more than capable to suspend and hold it on the gound instead of lifting up off the ground. Our arms and legs are (effective but inefficient) suspension system on the bike.

TobinHatesYou
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Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

Hexsense wrote:
Tue May 28, 2019 4:37 am
If the bump is truely micro, rider and bike are more than capable to suspend and hold it on the gound instead of lifting up off the ground. Our arms and legs are (lousy) suspension system on the bike.

From a comfort perspective, that's true. It's still lost watts at the tire itself.

In a way I'm kinda saying I wish BRR's drum test would put the weight on the tire with some allowance of vertical, horizontal and perhaps even a slight bit of yaw. Right now everything is static and the weight is applied from the drum.

Hysteresis losses in that 60-120psi range we like to stay in are pretty insignificant in the grand scheme. The most important variable within these parameters is compound. The second is surface contact. A supple cotton casing does create observational differences at high pressures, but at lower pressures the effect is less dramatic. It's probably one reason why vulcanized/tubeless tubs never really caught on...the aren't supple or fast. And probably also why having cotton casing tubeless tires doesn't matter so much in real world use.

JoO
Posts: 152
Joined: Thu May 04, 2017 7:30 am

by JoO

Back on topic:
Is tubeless more comfortable than cotton clinchers + latex inner tubes?

1) Tire pressure seems to me to be the dominant factor. If you can run lower pressures with tubeless it is likely more comfortable. Within reason of course don't suspect you gatorskins to magically become a flying carpet.

2) For the same pressure cotton + latex tubes is likely more comfortable. The sidewalls are covered in latex as opposed to vulcanized rubber for the tubeless variant. Latex is more "elastic". The cotton threads might also be marginally suppler (less stiff) then the nylon stands that are often used in vulcanised tires.

video by silca on latex tubes
https://www.youtube.com/watch?v=XUpq27mG2CM

According to Tom Anhalt the rr difference between a tubless tires with and without a latex inner tube is almost inmeasurable.
http://bikeblather.blogspot.com/

TobinHatesYou
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Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

JoO wrote:
Tue May 28, 2019 5:24 am

According to Tom Anhalt the rr difference between a tubless tires with and without a latex inner tube is almost inmeasurable.
http://bikeblather.blogspot.com/

Probably has to do with the porosity of the tire casing+latex layers. He had to add 60mL of sealant just to get it airtight, not that far off the weight of a latex tube.

zefs
Posts: 391
Joined: Sat Aug 05, 2017 8:40 pm

by zefs

JoO wrote:
Tue May 28, 2019 5:24 am
Back on topic:
Is tubeless more comfortable than cotton clinchers + latex inner tubes?

1) Tire pressure seems to me to be the dominant factor. If you can run lower pressures with tubeless it is likely more comfortable. Within reason of course don't suspect you gatorskins to magically become a flying carpet.

2) For the same pressure cotton + latex tubes is likely more comfortable. The sidewalls are covered in latex as opposed to vulcanized rubber for the tubeless variant. Latex is more "elastic". The cotton threads might also be marginally suppler (less stiff) then the nylon stands that are often used in vulcanised tires.

video by silca on latex tubes
https://www.youtube.com/watch?v=XUpq27mG2CM

According to Tom Anhalt the rr difference between a tubless tires with and without a latex inner tube is almost inmeasurable.
http://bikeblather.blogspot.com/
Again, since the tubeless variants are faster by 4w (based on bicyclerollingresistance) total you can use less air pressure and make the tubeless tire more comfortable without compromising in speed (so why use the same pressure). If that lower pressure of the tubeless tire makes up for the stiffer sidewalls I guess it does since it doesn't matter as much on lower pressures but would have to be tested back to back to get a clear result.

The 4w difference might not sound much but it's a 20psi difference for the same rolling resistance, although if you are already using low pressures you might not wanna go that low for the reasons already discussed above.

Also tire casing would play a role, Hutchinson for example are flexible (you can stretch them by hand) compared to the Corsa's and GP5K and from my experience this has a difference in ride quality as well.
Last edited by zefs on Tue May 28, 2019 7:55 am, edited 1 time in total.

JoO
Posts: 152
Joined: Thu May 04, 2017 7:30 am

by JoO

TobinHatesYou wrote:
Tue May 28, 2019 6:41 am
JoO wrote:
Tue May 28, 2019 5:24 am

According to Tom Anhalt the rr difference between a tubless tires with and without a latex inner tube is almost inmeasurable.
http://bikeblather.blogspot.com/

Probably has to do with the porosity of the tire casing+latex layers. He had to add 60mL of sealant just to get it airtight, not that far off the weight of a latex tube.
I don’t understand your remark. Do you believe a latex inner does add significant rr and that this was offset by the need to add a lot a sealant in the tubeless setup?

by Weenie


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