Any scientific testing includes certain assumptions and limitations - they chose theirs. I agree it would be more appropriate to test any kind of deep-section rim (even a 50mm road-focused rim).

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ZONE3 - We Last Longer

I realise that. I've done my share. But I think they chose very badly both by using a rider and using box sections. Thus my comment.

Of course. If I had a dollar for every time I disagreed with an author's methods, I'd be able to publish in predatory journals...

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ZONE3 - We Last Longer

Actually, no. IME, testing road tires with a latex tube results in the same Crr as with it set up tubeless.

That's the reason I don't bother testing them set up as tubeless.

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http://bikeblather.blogspot.com/

Which is exactly my point.....

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The latex tube is in there, just in liquid form…

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Eric Reid AeroFit | Instagram Portfolio
Aerodynamic Retul Bike Fitting

“You are experiencing the criminal coverup of a foreign backed fascist hostile takeover of a mafia shakedown of an authoritarian religious slow motion coup. Persuade people to vote for Democracy.”

I'm not sure if I understand your point then. You are saying above that a test of the TL tire with and without a latex tube in it is somehow better than comparing the clincher w/latex vs. the TL?

The former doesn't give you much new info (i.e. they will test ~ the same), the latter tells you if you gain anything running the non-TL w/latex vs. the TL.

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http://bikeblather.blogspot.com/

I took a look at these results and I'm mind blown by the width/height difference between the 4000sii and 5000. I can't fit a 25mm 4000sii on my NP3 on wide rims (enve 7.8) . Now I'm debating if the 25m 5000 will fit, since it's much less wide and high...

Yes, the 5000, not the 5000TL. They do not specify tube type. But specify 90 PSI.

Front wheel : 23mm better for aero I guess. Plus 25mm does not work on my P3
Rear wheel : being a bit heavy (170lb) I will stick with 25mm on rear wheel, i think RR gain (at 115 PSI) will largely overcome slight aero loss, and is more comfortable

I’m not willing to give up puncture resistance for a minute. Over 20 races and I still have yet to get a flat with the 4ks2’s. I’ve had 2 flats in training in 5 years.

+1

Used GP4000S2 this year
Was planning Michelin Power Comp for next year. But GP5000 is looking good. Waiting for puncture tests :-)

I don’t need a test. Can’t be worse than the 4ks2’s. They already said it’s better.

Funny.

I am actually totally fine with their rim choice. I think it was Cycling Weekly that did a windtunnel test using the 25mm Michelin on something like 10 different aero wheels. That's a nice tire, but nobody designs for it. There were some really odd results that I can only attribute to the tire being different from the shape used to design the rim (e.g., the Rovals were absolutely terrible. Worse than some open mold rims). At least the box section rim indicates differences in the profile of the tire as the leading edge of an airfoil and whether the texture encourages flow attachment out to higher yaw angles.

This is "early" data but do you have any speculation as to how the tubeless tire with a butyl liner manages to perform on par with the regular clincher with a latex tube?

If you look at this test: http://www.cyclesetforme.fr/...-gp-5000-et-5000-tl/

...you'll see that he standardized at 6 bar and that the 25mm 5000 tl actually measured nearly 1mm narrower than the 25mm clincher... so if anything casing tension should have biased the test in favor of the clincher. The same goes for the RS tire which measured a full 3mm wider. I'm not sure how repeatable this tester's setup is but it sure seems like he's making a decent stab at it. His comment of switching from latex to butyl adding "10watts on the rollers and 2watts in the real world" is a bit strange...

It would not shock me if Continental took the approach of focusing improvements of the 5k on rolling resistance and weight. Then simply make claims on durability and puncture resistance that are on par or better than the 4kS2. Weight is super easy for anyone to confirm. Rolling resistance is going to get independently tested by multiple sources. But puncture resistance is highly anecdotal. For every person that says they get 2-3 flats per year on their 4k tires, there is another person that says they never got one in 5 years.

Overall, the 4k tires get good reviews on general puncture resistance due to the thousands of anecdotal responses from users...not really because Continental says it's good. So I don't think we'll really know if we'll know for sure about this for a while. And even if they puncture resistance on the 5k tires are 50% worse in reality, will anyone really notice the difference. That person who was getting 2-4 flats per year may now get 3-5 flats per year. That person who never got a flat in 5 years may now get 1 in 5 years.

I would love for it to be true that Continental lowered rolling resistance, lowered weight, maintained or slightly improved aero, and maintained or slightly improved puncture resistance. I'm just not going to hold my breath at this point.

I’m sure it can be tested somehow.
But what other test can be be better than empirical observation. 1 puncture every so often plus 20+ races of no flats is a strong evidence of some puncture resistance.

I get where you are coming from Tom. You make a valid point that the original test may be better. But I'm merely trying to point out that a tubeless tire setup tubeless is NOT any faster than with a latex tire in it. Your corsa speed test proved that but there are countless people out there that still think a tubeless tire is faster. Mostly due to the marketing of TLR wheels and tires.

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Rolling resistance will be tested seriously by independent sources
Aero also
Weight is easy to check

AND

Puncture resistance will be seriously tested also by at least one independent source (tread and lateral)
Durability can be easily tested by thousands of user

Finally, the only one parameter not seriously tested (to my knowledge) will be grip

Perhaps it's not a butyl liner? I don't recall Conti saying...

Best I can tell, he's using even smaller diameter rollers than I do, so that 2W to 10W "amplification" could make sense.

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http://bikeblather.blogspot.com/

Multiple press releases had it as a butyl liner. Whatever they're using, initial reports seem promising.

What I'm wondering is why do they even make a non tubeless version.

Because tubeless + inner tube will be heavier and less performing than standard + inner tube.
Not even sure tubeless alone will be better than standard + latex inner tube (apart maybe self healing capability from sealant). This comparison will be interesting, because up to now, from the serious comparison I've seen, the tubeless do not win. But it will come. Will it come with GP5000 ? May be.

But for sure tubeless + inner tube better than standard + inner.... no

And non-tubeless is ... mmmm... more than 90% of the market.

Why make a competitive product for 90% of the market... instead of a non-competitive product.... mmmm ,,,, wondering....

From what I see the tubeless tyre with latex tube is 2 watts faster. not calculating.,how hilly a course has to be to make it slower than the non tubeless due to weight, but I imagine it will be a lot of hills required

I would imagine that for most the heavier tubeless with latex tube will be faster.
I guess the reason they make the non tubeless is purely for the reason that conti believes most people are to stupid or lazy to use latex tubes ( they might have a point there but still it's not performance in my mind it's more an "Ignorance" tyre)
I don't think many people have complained that vitoria speed is only avaialbe in tubeless version.

I guess I'm coming from this point as I never use the 4000 as for me it's to slow for racing and to expensive for training.

Do not know where you find these 2 watts.

On the french site the guy (Alban Lorenzini) test "5000TL alone" vs "5000 + latex" and find 0,3w difference at 30km/h (calculated from roller measurement processed), probably less than the margin error for this test process (roller and 6 bars pressure - quite low).

So, as I say, "5000TL alone" might be slightly better than "5000 + latex", or not, but I will wait for more precise test on big drums to say.

And for sure, if you add an inner tube to the 5000TL, it won't help.

Thanks for this second link. Interesting also.

Similar results for "5000TL alone" and "5000 + latex".

Alban says in the comments that his recommended config is :
5000 + Latex for rear wheel
5000 + Butyl front wheel

due to similar perf with a "5000 TL alone" x2 config, and much better repairing possibilities with the 5000, compared to 5000TL.