Vittoria Corsa Pro Speed rolling resistance data

[Mocs123]

@xav - One question on your chart - is the Contintinental GP5000 TT TL on your chart the same as the TT TR that is currently sold? I can't seem to ever remember a TT TL being sold, just the regular TL, the S-TR, and the TT TR.

[da123]

Thanks Xavier for the updated test.

I have a question which may related to this thread and it has been boggled my mind for quite sometime. Do you have any insight as to why Specialized sponsored pro teams still use the S-Works turbo cotton tires? On road application that does not surprise me given they use it with latex tubes and it’s still one of the fastest road tires (in your test).

However what I don’t get is in the time trial application - they also use the turbo cotton. Which looks like they are leaving 6-10 watts (per pair) on the road. I am sure for really critical race specialized would not mind Remco using an unlabeled corsa speed tlr or conti tt?

Or tire crr does not matter much for some teams in the grand scheme of things? I know the crr is constant vs cda where you get exponential benefit as you go faster. But that can’t be it given how obsessed to minute details some of these riders are.

It's only 5w for a pair of wheels at 45kph, and that's with the advent of the new Corsa Pro Speed. Compared with the old Corsa Speed it's 4w/pair, and vs. the GP5000 TT it's 2w/pair so not that great a difference, and I think for the riders knowing they can corner just like on their road bike with the same tyres is of some benefit. Specialized also really don't let a lot of debranded stuff go through (yes yes, I know about the wheels ), and there are always compromises with Pro Tour setups, regardless of the team.

Certainly with things like helmets and skinsuits as a TT specialist sometimes you'll be fine one year with a good setup and the next year it just won't work for you, which can be quite frustrating for the riders that monitor it themselves.

Cheers for this. Any observations on how easy they were to set up tubeless compared with the Conti TT TLR? Did they require more sealant? Thanks, Dave

[ichobi]

Wow. I did not notice that it was per pair. Which means practically the turbo cotton is as fast as or faster than the normal Corsa Pro and gp5000s tr. obviously it’s clincher only but it’s light and it’s almost 10 years old since it was launched!

I went and check aerocoach ranking again and yes the turbo cotton is faster than a few tt tires and a lot more modern tlr tires.


No wonder the team kept using it instead of specialized’s myriad choices of tlr tires, which i find mostly mediocre.


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[TobinHatesYou]

Wow. I did not notice that it was per pair. Which means practically the turbo cotton is as fast as or faster than the normal Corsa Pro and gp5000s tr. obviously it’s clincher only but it’s light and it’s almost 10 years old since it was launched!

I went and check aerocoach ranking again and yes the turbo cotton is faster than a few tt tires and a lot more modern tlr tires.


No wonder the team kept using it instead of specialized’s myriad choices of tlr tires, which i find mostly mediocre.


Sent from my iPhone using Tapatalk

I thought you were using BRR’s data, which even when accounting for the butyl tube handicap, has the Turbo Cotton much slower than the fastest TT tires.

[da123]

Wow. I did not notice that it was per pair. Which means practically the turbo cotton is as fast as or faster than the normal Corsa Pro and gp5000s tr. obviously it’s clincher only but it’s light and it’s almost 10 years old since it was launched!

I went and check aerocoach ranking again and yes the turbo cotton is faster than a few tt tires and a lot more modern tlr tires.


No wonder the team kept using it instead of specialized’s myriad choices of tlr tires, which i find mostly mediocre.


Sent from my iPhone using Tapatalk

I thought you were using BRR’s data, which even when accounting for the butyl tube handicap, has the Turbo Cotton much slower than the fastest TT tires.

Is it? Turbo Cotton 24 is 10.1w with butyl tube on BRR. With latex, realistically 8.5 ish. That's only 1.5w slower per tire than the fastest TT tires, so 3w over a pair of wheels.

[xav]

@xav - One question on your chart - is the Contintinental GP5000 TT TL on your chart the same as the TT TR that is currently sold? I can't seem to ever remember a TT TL being sold, just the regular TL, the S-TR, and the TT TR.

Yes it is the same, we just changed the suffixes on the tyres so it was obvious what was what. All the tubeless tyres should say "TLR" after them in the chart but looking at it now they don't so that needs changing

[toxin]

The "105% rule" or whatever it is really doesn't hold true with modern wheel technology and especially variations in the location of maximum rim width (this is really critical to tyre choice). It's just too simplistic a metric to capture what's really happening lower down the wheel rim so we don't subscribe to it and instead either collect/publish the tyre data ourselves on our own products, or get people to pester other companies to find out what the actual aero data is they've collected.

VINDICATION! I've been prattling on the same thing here and nobody takes me seriously

[MTM]

Thanks Xavier for the updated test.

I have a question which may related to this thread and it has been boggled my mind for quite sometime. Do you have any insight as to why Specialized sponsored pro teams still use the S-Works turbo cotton tires? On road application that does not surprise me given they use it with latex tubes and it’s still one of the fastest road tires (in your test).

However what I don’t get is in the time trial application - they also use the turbo cotton. Which looks like they are leaving 6-10 watts (per pair) on the road. I am sure for really critical race specialized would not mind Remco using an unlabeled corsa speed tlr or conti tt?

Or tire crr does not matter much for some teams in the grand scheme of things? I know the crr is constant vs cda where you get exponential benefit as you go faster. But that can’t be it given how obsessed to minute details some of these riders are.

The sponsored teams get different versions of the Turbo Cotton for different events/disciplines - including versions you can't buy.

[Matte86]

Thanks Xavier for the updated test.

I have a question which may related to this thread and it has been boggled my mind for quite sometime. Do you have any insight as to why Specialized sponsored pro teams still use the S-Works turbo cotton tires? On road application that does not surprise me given they use it with latex tubes and it’s still one of the fastest road tires (in your test).

However what I don’t get is in the time trial application - they also use the turbo cotton. Which looks like they are leaving 6-10 watts (per pair) on the road. I am sure for really critical race specialized would not mind Remco using an unlabeled corsa speed tlr or conti tt?

Or tire crr does not matter much for some teams in the grand scheme of things? I know the crr is constant vs cda where you get exponential benefit as you go faster. But that can’t be it given how obsessed to minute details some of these riders are.

The sponsored teams get different versions of the Turbo Cotton for different events/disciplines - including versions you can't buy.

Could you tell anything more about the non released ones? Maybe we could infer something on future releases
Thanks

@Xav maybe I missed it, but how was setting them up?Would you reckon that for ‘daily’ use they require more sealant than a GP5000 TT?
Thanks

[Wildh]

Thanks, I think we like(d) the 105% rule because it was simple to understand, if not to apply.

Now it sounds like we have to rely on manufacturers doing testing and actually telling the truth about it. Transparency is a big issue in the cycling industry and to a large extent outfits like yours, Tour and BRR are the only way to truly verify manufacturers' claims. Keep up the great work.

I know, me coming on here and saying "forget the 105% rule" but not giving an alternative apart from "go ask the manufacturer" is a bit rubbish, but honestly it really is the right answer! Certainly getting independent data for tyres and wheels when it's not the manufacturer doing the testing is almost impossible - from our perspective we have a huge volume of data on other brands and their wheel & tyre interactions but we don't publish it because it's not our job to help them sell their products. But hopefully over time the more the consumer demands data the more that brands will be obliged to provide it, which is only a good thing for everyone

This is good info. I've often posed the question and searched for data, but haven't found anything concrete or even consistent.

I'm still very curious on what the loss is on say a 19mm internal rim 26.5 external running a 25 tire vs 28...as a whole system. Is it .05% greater drag...or 15%?

It'd be really interesting to see a an average of your info across 5 different wheels of similar widths and depths (with the same frame) and only changing the tire width.

[xav]

@Xav maybe I missed it, but how was setting them up?Would you reckon that for ‘daily’ use they require more sealant than a GP5000 TT?
Thanks

Ah sorry - they seated better than previous Corsa Speeds, but no long term use info yet I'm afraid. I'll be racing on them this year but I won't run them tubeless, some of our team riders will though so we'll get info one way or another!

[xav]

I'm still very curious on what the loss is on say a 19mm internal rim 26.5 external running a 25 tire vs 28...as a whole system. Is it .05% greater drag...or 15%?

It'd be really interesting to see a an average of your info across 5 different wheels of similar widths and depths (with the same frame) and only changing the tire width.

Just as an example then, and in contrast to what I said earlier - here is a graph from our internal testing showing the difference between swapping between a 25mm and 28mm GP 5000 S TR on an AeroCoach AEOX Zephyr (78mm) front wheel and a Princeton 7580 (average 77.5mm). It's not loads, only a couple of watts at TT speeds.

[Matte86]

@Xav maybe I missed it, but how was setting them up?Would you reckon that for ‘daily’ use they require more sealant than a GP5000 TT?
Thanks

Ah sorry - they seated better than previous Corsa Speeds, but no long term use info yet I'm afraid. I'll be racing on them this year but I won't run them tubeless, some of our team riders will though so we'll get info one way or another!

Thanks for getting back!
Out of curiosity why aren’t you running them Tubeless?
More broadly Would you suggest people to use them Tubeless or with a TPU tubes/latex?
Thanks

[xav]

@Xav maybe I missed it, but how was setting them up?Would you reckon that for ‘daily’ use they require more sealant than a GP5000 TT?
Thanks

Ah sorry - they seated better than previous Corsa Speeds, but no long term use info yet I'm afraid. I'll be racing on them this year but I won't run them tubeless, some of our team riders will though so we'll get info one way or another!

Thanks for getting back!
Out of curiosity why aren’t you running them Tubeless?
More broadly Would you suggest people to use them Tubeless or with a TPU tubes/latex?
Thanks

It just means I can swap out tyres quickly to adjust to conditions/road surface etc. For example when I travel abroad to race you often don't know what the road surfaces/conditions are going to be like so I'll take a selection of tyres for broken roads/wet weather and so on.

Whether you run them tubeless or not is entirely a personal decision, speed wise it's the same so whatever you feel most comfortable with/happiest with is best

[Matte86]

@Xav maybe I missed it, but how was setting them up?Would you reckon that for ‘daily’ use they require more sealant than a GP5000 TT?
Thanks

Ah sorry - they seated better than previous Corsa Speeds, but no long term use info yet I'm afraid. I'll be racing on them this year but I won't run them tubeless, some of our team riders will though so we'll get info one way or another!

Thanks for getting back!
Out of curiosity why aren’t you running them Tubeless?
More broadly Would you suggest people to use them Tubeless or with a TPU tubes/latex?
Thanks

It just means I can swap out tyres quickly to adjust to conditions/road surface etc. For example when I travel abroad to race you often don't know what the road surfaces/conditions are going to be like so I'll take a selection of tyres for broken roads/wet weather and so on.

Whether you run them tubeless or not is entirely a personal decision, speed wise it's the same so whatever you feel most comfortable with/happiest with is best

Thanks!