rolling resistance for the spreadsheet. i'm curious if that would affect it at all when you change the effective width of the tire from ~20mm to probably ~23mm.

It would...but then you'd drop the pressure to better match the mounted width...and end up at the ~same Crr value.

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http://bikeblather.blogspot.com/

The added complication is that existing Crr results for 20c and 23c SS on Tom's chart are the previous generation tires. BRR tested the 23c with a butyl tube and found it rolled slower than the GPTT. Some others on ST reported testing early versions that were bad vs. newer production tires that were faster. Some of those testing indicated the new 20c rolled better than the new 23c.

The new SS 20c measures more like a 23c and the 23c is more like a 25c or larger. The BRR test listed the 23c at 25mm wide on a 17mm rim. I think this SS 23c width difference shows up in TG's tunnel test result chart from last year.

right. i bought 20c supersonics to race on this year on jet+ rims for this reason. i need to check whether i got the old or new version though as i know some of the old 20c were still available when the 23 was not. I will be mounting these up this weekend and will try and get some measurements on jet + rims at a few different pressures.

Since you asked the ones that are on my bike right now. Until they wear out :0)

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All the new GP SS are supposed to have the smooth center with textured tracks to each side like the GP TT instead of being entirely smooth like the previous generation GP SS series.

There is also this reference for a hard manufacturing date: https://www.continental-tires.com/...aq/tyre-construction

I used to run GP 4000S II"s exclusively, but kept flatting them. Some have great luck with them, I didn't. Hated riding Gatorskins, too harsh of a ride for me, rode those previously. Switched to Michelin Pro 4 Endurance tires, loved them. Handled and rode great, and rarely got flats. Switched to tubeless and have been running Schwalbe Pro One tires. They don't flat often, are race tires, don't last particularly long, but have great ride quality as a race tire should. Hunting for a more durable version of same, not sure what to get next.

Ya no problem. I put a SS20 (latest Gen 3) on a Jet 6+ and 3+. The profile passed the eyeball wind tunnel test, with it being less of round "ball" on the front of the wheel compared to a TLR.

I would appreciate input from anyone who knows more about airfoils and whether my interpretation is about right.

I tested them using my Hobo roller testing (put different tires on the front wheel and measure total wattage for the entire bike at 24 mph). Let's call it 1 watts more for the "out of the box"a SS than a TLR with about 300 miles. Installed width for the SS=24.3 vs. 27. for the TLR 23.

Our cycling team gets a good deal on the turbos and they seem to be fine overall. I also like the Vittoria Rubino for a cheap training tire.

I’d like to try something else but just keep coming back to the GP4000SII. I can’t even be arsed with latex tubes anymore on my roadbike. Rain, shine, winter, summer, butyl tubes and a ‘shallow’ flo30. Who needs disc brakes or tubeless?

I’ve nearly ordered a set of regular s-works turbos a few times. and I’m a sucker for a skinwall, but so far I’ve avoided the siren call of a Vitoria corsa.

So, Tom, are turbo cottons your race tire? Or corsas?

I do agree with that but I guess we than should point out that the turbo cottons dosnt seem to do to well at lower pressures. So on a more common ok surface the test difference is not that far off from noise and given that not all tyres of one product test the same.
But I totally agree that for a roady that is still a very good tyre. Not my cup of tea but dosnt suprise me that somebody like you would love it.

I have never used the tyre but I am sure it's a very good tyre

What kind of "racing"?

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http://bikeblather.blogspot.com/

In what way? I run them at 80-85psi (I weigh ~165lbs) all day long...sometimes lower if there's some "adventure" on the route...

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http://bikeblather.blogspot.com/

The BRR site is extremely misleading. The TT they tested was a 25 mm so of course it’s going to roll faster than a 23 SS at the same pressure. It’s amazing to me how long it takes to find out what size they actually tested for each tire. It’s buried in each tires test report. They really need to update the front page (specifically their top tire charts) to show what size they are referring to when ranking the tires.

There is absolutely no freaking way a 23 mm TT rolls faster than a 23 mm SS. Yet some people believe that because of the misleading BRR site. Why they didn’t test a 23 mm TT is beyond me.

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I don't really look to BRR as a primary source for Crr because they use butyl tubes. Their info is more useful to help validate what is posted elsewhere.

I do use Tom A's Crr testing results and he always uses latex tubes. But in direct answer to your point about the 23c GP TT vs. 23c GP SS, Tom's data shows the 23c GP TT did roll faster than the "previous generation" 23c GP SS. He hasn't published any tests of the current generation GP SS in either 20c or 23c. Those that have shared testing results found that the new 23c GP SS doesn't roll as well as the previous generation. There have also been reports of the new 20c GP SS rolling better than the new 23c GP SS. Until tests of both are published from the same source this can't be verified.

Conti's rolling production changes have made it difficult to keep up with Crr and wind tunnel testing of their latest production variants. Vittoria releasing the extremely fast rolling Corsa Speed TLR took a lot of focus off testing the newest Conti tires:(

I don’t have any experience with the old SS so I can’t really comment on it.

I’m talking specifically about the new SS and new TT. Comparing the new tt to the new SS (23 mm). They are exactly the same tire with the exception of a Vectran belt layer on the TT. I have both tires (along with a 20mm SS) and have a really hard time believing that a 23 mm TT rolls faster than a 23 mm SS.

Jens had some testing about a year ago on both of these tires. His first test showed a TT rolling better but many were suspect on this because of the vectran belt layer difference. Turns out, he had a couple bad SS tires and when he retested, the SS wins by like .002 I believe.

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This website showed all the rolling resistance tests together in a good summary.
https://intheknowcycling.com/...est-road-bike-tires/

Basically, the Continental GP4000sII, Zipp Tangente Courses, and the Specialized S-Works Turbo are all pretty equivalent in terms of Crr.

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