I agree that the "white paper" culture is gone. I mentioned this in the Felt IA2 thread. A few remain, like Flo wheels.

Also the market for independent testing is pretty thin. The "peak aero" independent test was a huge effort with a lot of volunteered time. Not something that can be sustained. When subscription-based media posts independent testing we tend to copy and paste the results here and then taking turns trying to impress each other by trashing the methodology. And I doubt it drives any big subscription numbers. So why should media sites continue to try to do "budget testing?"

CeramicSpeed bought out the drivetrain testing guys.

Occassionally ERO and others post tidbits, but they have businesses to run, and that business model isn't providing a free public service.

We still get some rolling resistance independent testing, as it doesn't take a much in the way of equipment overhead.

So I'm not sure what we can really expect.

I have the RSL75 wheels on my speed concept. Overall, I am really impressed with the wheels. A 25 mm tire looks like a 28mm on these wheels. They don’t seem overly twitchy as I have ridden them in 20+ mph crosswinds without major issues. The dtswiss hubs are really nice. No tire levers are required for these wheels. I’ve mounted several tires without any tools with zero issues. I’ve had mine setup with tubes but I plan to convert them to tubeless in a few weeks. I’m not sold on the rim strip quite yet so I plan to use Stan’s tape.

My only complaint is that wheels are a little too deep for training. I would gladly get one of the smaller sets for training.

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blog

It was another brand that claimed 17 with some "creative" explaining. They published raw data and you could see that old bike to new bike was 2 watts. But all fan-boys of the brand heard was 17watts..

But if we talk about the SC, this is a paragraph Dan wrote on the SC article

"About half of that 16 watts is what happens below the “waist” of the bike, that is, at the wheels, tires, the interaction between the wheels and the fork. Some of you are going to cry foul at this, but Trek says that one-third of the speed increase is in the latest model Bontrager wheel and that’s discounting the aero increases in the wheel. It’s just rolling resistance. When I pressed the engineers on this it’s simply Bontrager’s move to a wider inner bead width. Just the move to a 23mm inner bead – just that – gets you 5 or 6 watts. That seems hard to believe. But this is what tire testing company Wheel Energy reported back (Trek relied on a third party for this). I would have some questions about protocol, but that’s a subject for another day."

I liked the direction it was going. Take the manufacturer claims, analyze, pick apart, question......the problem is I'd like the "subject for another day" be addressed eventually. "It's just rolling resistance".....hmmmmm.... that is actually pretty easy to test.

IMO, ST has the clout to ask for the data and ask the hard questions. I would think over time manufacturers would step up their game.

They got the 17watts in a super disingenuous way. They listed in a single place (likely to make it less obvious) that it was in comparison to the tubular version of the xxx wheel. As tubulars are much slower than clinchers both aerodynamically and rolling resistance wise (then add in using narrow tubulars on a bad road surface vs 25 or 28mm tires), they can easily inflate those numbers by making a ridiculous comparison.

I really do wish they came out with white papers again. Trek had a history of great white papers old Aeolus D3, Aeolus XXX, gen 1/2 speed concepts, and three madone versions. I feel that they stopped writing white papers as if they presented results truthfully, the gains would be so small that no one would buy new equipment.

Does it come with a 18t or 36t Ratchet? Have you upgraded to the 54t yet?

Yes, this exactly. That's a great example of where Slowtwitch (and Dan in particular) were on their 'A game' that day. It was a proper critical appraisal but was still pitched at the right level. Too many magazines just can't/won't do that.

As another data point, I am on the new SpeedConcept with the RSL 75's (set-up with Continental GP5000 tubeless) and I am faster than last year with the last-gen SpeedConcept and XXX90's set up tubeless with the same tires. Handling has been reasonable is the gusty spring winds. Still may go full Disc in the rear, but that's for the small gains and because I already have a place for the rear RSL75 on my Emonda (handling is good enough for fast group/racing in my experience so far). IMHO, of course.

Hey there! For the calculation of the XXX to RSL wheel difference, we used clincher XXX wheels and clincher RSL wheels, no tubulars involved. we did find an article (https://www.bikeradar.com/...aeolus-rsl-51-62-75/) that incorrectly references the claim to tubular XXX wheels, but this probably comes from confusion of the shared name of “XXX” for our old performance clincher and tubular wheels. For the aerodynamic portion of the claim, both wheels were wind tunnel tested with the same physical clincher tires swapped wheel-to-wheel (Bontrager R3 25c tires). As Dan mentioned, the rolling resistance portion comes from a third party test with Wheel Energy, but again with the same R3 25c tires on both wheels.

As for including those wheel results in the Speed Concept claims, that was done because the old Speed Concept was rim brake only, which caused some difficulty in comparing the two bikes. The new bike allows a rider to take advantage of all the R&D we’ve put into our new disc wheelsets that was not possible with a rim brake bike, so we did want to show what it looked like as a system to move from a rim brake tri bike to a disc brake tri brake, as that’s a question we get a lot. We split out the portions of the gain that were coming from each particular portion (rolling resistance vs aero) in our media launch materials and our online webinar.

Speaking of the webinars, that’s kind of where we’ve gone to replace the white papers in an effort to engage more people, but we absolutely appreciate reading the feedback here. The engineers like having the white papers up to showcase the work, but we think writing them can be a tough sell with the time involved. Another place we’ve set up to host whitepaper-like content is our Trek blog, that the Trek Performance Research group sometimes posts to. The more feedback we get like this, the more motivated we’ll be to post some more technically dense material up there!

RSL Wheel webinar: https://www.youtube.com/watch?v=Lx0htMHaBlg
Speed Concept Webinar: https://www.youtube.com/watch?v=RTyDjAXVXYY
Trek Performance Research Blog: https://blog.trekbikes.com/...erformance-research/

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Mitchell Mathews | Community Manager | Trek Bikes | @mitchmathewz

Good to have the confirmation it’s vs clinchers as the bikerumor (https://bikerumor.com/...aeolus-pro-51-depth/) launch article mentions all the comparisons are vs tubulars multiple times.

What's the widest tire/rim I can fit in my 2015 Speed Concept frame?

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Happy to confirm that - we just wanted to jump in and make sure that was known!

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Mitchell Mathews | Community Manager | Trek Bikes | @mitchmathewz

26mm is the suggested max outer rim width for that generation Speed Concept - this is ultimately all that the brake pad spacing would allow when fully opened up in the adjustment.

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Mitchell Mathews | Community Manager | Trek Bikes | @mitchmathewz

tire or rim? if rim, inner or outer width?

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Dan Empfield
aka Slowman

In my head I figured that the outer was self-identified, sorry there! The max is a 26mm outer rim width - which is a tight squeeze.

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Mitchell Mathews | Community Manager | Trek Bikes | @mitchmathewz

OK. but i don't see that the rim is the issue here. i've never had a rim hit the frame. the tire, yes. i've had all 3 speed concept editions, and i never had a tire clearance issue. but i think i probably rode 23mm in 2011, 25mm in 2014, and i'm likely to run 28mm now. thankfully, the new SC handles 28mm tires easy peasy.

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Dan Empfield
aka Slowman

Agreed. It's always the tire that hits the frame first - which I've seen comments about even a 25c tire touching the frame for 2nd gen SC owners. We list a 25c tire being the max tire size for that gen too - but that is conforming to our generous ISO standards.

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Mitchell Mathews | Community Manager | Trek Bikes | @mitchmathewz

When you say "25c", what does the c mean?

My understanding is that the "c" is historically referenced from an old French system for the wheel style and tire size in millimeters. So the next time you shop for road tires, you'll commonly see them listed as 700x25c, for example, which is stating the tire is 25mm wide.

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Mitchell Mathews | Community Manager | Trek Bikes | @mitchmathewz

I thought the tire size was 700C.

Hello,
Just wondering if anyone has been running 28" tires on this wheelset, maybe 25" in the front and 28" in the rear. I will buy new tires for the racing season, most likely the GP5000 TT (latex/tpu tubes), and I'm considering going 28" for both wheels.
Any experience/feedback is appreciated.
Thank you.