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Discussion Starter · #1 ·
And if not, why?

According to Velo News - Where the rubber meets the road: What makes cycling tires fast? | VeloNews.com - the range of watts that account for the rolling resistance of race tires is massive - from 60 watts - to 120 watts (set) with the tires they tested.

Even being "fair" in the selection of tires - picking a $160 set of Schwalbe tubulars - there's a 20-watt advantage to the Spec' Cottons. 20 Watts. Imagine, on your last race or hard ride, just upping your avg by 20 watts.

We read/hear about all the watt savings from aero wheels, frames, helmets, etc. but those are A. much smaller than this tire test and B. only when you're the one in the wind. The tires' rolling resistance doesn't care about your headwind or lack thereof.

So... what am I missing? Are the test results bull****, or is every rider currently switching to the Spec' Cottons?
 

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Pros pretty much use tubular tires, and they did not test any tubular tires in that article.

They also did not test some of the fastest existing clinchers, such as the continental supersonic or TT or force/attack. It also doesn't have results from newer tires such as the Vittoria graphene tires or Michelin power.
 

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Here's another site that has tested a lot of tires: Bicycle Rolling Resistance | Rolling Resistance Tests

They have a similar order to the rankings, although the spread is much smaller. However keep in mind their test is done at 29 km/h while the velonews one was done at 40 km/h so that accounts for some of the difference.

Also check on Tom A's blog blatherboutbikes for testing of bother aerodynamics and resistance.

Flo also recently did a large tire wind tunnel study looking at both aerodynamics and rolling resistance of tires on their wheels.

Josh Poertner at Silca has had several interesting blog articles recently looking at rolling resistance and aerodynamics and how it is affected by pressure and road surface.

There's lots of sources of good information out there.

edited for typo
 

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The performance difference (Crr) between a set of Specialized Turbo Cottons and a set of Tufo S33's is obvious. But when you take a set of Turbo Cottons and ride them back to back with the latest version of a Conti GP4000, for example, the difference in Crr becomes very much less noticeable. Considering aero, durability and cost the GP4000 is way more attractive than 2W/tire the Cotton has over the GP4000...For me. And I would say I have a healthy obsession looking for free speed. But I still have limited income. And not being a pro or top amateur I tend to run tires longer than I should. Given how thin the tread is on the Cotton to begin with they will never be as reliable as I need a tire to be.
 

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Roger that. But, the question still (somewhat) stands - who would not spend a few dollars more to save 20-50 watts?
People who know it's BS.

Just an anecdote but my speeds are pretty similar when I use tougher tires for crappy spring road conditions. Pretty sure I'd know if I was putting out an extra 50 watts to do it. So either I have a spike in fitness in the early spring after goofing off for a couple months, I'm putting in much more effort and don't notice it, or that watts savings between rugged tires and cotton race tires isn't 50 watts. I'm going with the third option.
 

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I think Pro's ride on the tires of their sponsor. Amateur cyclists without sponsors just buy what they buy and I do not know about that either. Locally all the racer types are racing cyclocross and again I do not know what tires they prefer.

However in the world I live in of recreational road cyclists I would say the most popular tire in this area is the gatorskin as it has very good durability. I ride Michelin service course at the moment but I generally shop sale items and will ride something different next time most likely.

Anyway I would not spend extra for more watts. I just go for bike rides with friends or solo and am not in training for the big race or anything.
 

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Discussion Starter · #13 ·
I ride Michelin service course at the moment but I generally shop sale items and will ride something different next time most likely.
This is a great example of what I'm getting at - you're giving up 25 watts by not riding (example) Conti 4000s IIs. 25 watts! Those tires are on sale right now for $78 for a pair. If you've ridden with a power meter, you know that jumping from say, 250 watts to 275 is an enormous feat. Just hard to believe that there's that much advantage rolling around for $50 or so
 

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Our roads are generally course chip seal, I wonder what I'm giving up by running 28mm Roubaix Pro's at 65psi?
A Specialized 2 for 1 deal is hard to pass up.
 

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Most serious racers I know, myself included, race Conti GP 4000s II.

I tried the Specialized model right below the cottons but the performance in the wet was so abysmal I ditched them for the Contis.

CRR is a big consideration, but also have to consider flat protection and tire wear, especially at those prices. The Contis check a lot of the boxes for people not getting their stuff for free.
 
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