While that could be true for the general TR population…this is literally the “Best RACING Gravel Bike” thread, so I think it’s reasonably safe to assume that most of us are racing these bikes. That’s at least the context we should be operating under.
While I don’t completely disagree with you that the use of big MTB might be a little overdone, there are plenty of races that have far more than 90sec of terrain where a larger tire is absolutely the right tool.
What else is there?
Hystersis + Suspension Losses = Impedance
Aero
Weight
I don’t think the “science” has moved on. The only new stuff from 2025 is from John Karrasch and Cycling News. The former generally reinforcing what we already thought with respect to the first two variables. The latter; confusing and often contradictory findings from the Silverstone Pedaling Efficiency Rig.
Gravel tires, 50mm and smaller, have been getting faster but at the same time seem to be giving up puncture resistance and durability to do so. This may be a worthwhile trade, but often isn’t, given the relative speed for the Dubnital/Thunder Burt.
I do not think that there is any new science that disputes the current framework, nor do I think wide tires are an outdated 2024/25 concept. Choosing the right tire for the course is important to many, while to many others, we’ve settled on just running 2.1s/2.2s.
I was partially on XC tires in 2023 and 2024, and went all in for 2025. My results have been better. The fastest XC tires may have drawbacks and limitations, but gravel tires as a whole have not surpassed them. I’ve heard many different privateers talk about how slow XC tires feel pulling through or going off the front and almost in the same breath talk about getting bounced around on the rough stuff so much with narrower tires without realizing they are discussing two different variables of vastly different magnitude.
While I think that “horses for courses” is an acceptable viewpoint, I’m not entirely sure it’s supported by the framework that led everyone into wider tires in the first place. Previously “we” were overweighting BRR hystersis metrics, and now I feel “we” are overweighting aero losses.
But as I said, I’m doing better on XC tires, I get through more selections and the selections where I am eliminated are much more contentious than when I was running gravel tires. From what I see racing, I think most riders would be faster on XC tires.
IMO “Race Gravel” will settle at 50mm clearance, 45mm just seems a little too narrow even with all the aero claims. Schwalbe at least seems able to make tires that are “just as fast” and as the sport is able to generate and internalize more aero results the difference may be minimal when evaluated in the whole.
Ronan over at Escape Collective has been doing some very detailed work on tire width, pressure, etc all in ‘real world’ settings. So far it has just been with road tires though. It’ll be interesting if he expands his work to off-road tires.
It this actually the case though? Comparing the new-ish Hutchinson Caracal to the Thunder Burt it seems like the former has better puncture resistance and grip? And rolling resistance though they were tested at different PSI (which makes sense given they are different widths)
This is what I do. I run a 2.1 in on some courses or rides that are a bit more rowdy. But I personally find that these wide tires don’t feel/handle on as good on pavement or nice gravel, so in those cases I run a narrower tire which I enjoy/feel more confident riding on
BRR tests smooth surface wet grip and it does that very well, but knobby tires consistently score worse there. The Caracal also has better smooth surface wet grip than a 2.4" Barzo but I know which one I’d take for cornering on gravel.
How much of the course are you actively cornering?
Optimizing for edge cases does not lead to increased overall performance.
Escape Collective (and Cycling News) has an issue with making assumptions about tire construction when comparing different tire widths within the same brand and product line. The testing with the P Zero fails to account for the difference in construction of the larger models and attempts to generalize what is a specific result. This is the same issue they had publishing the results from Marc Graveline’s trial with Pirelli MTB and Gravel tires with suspension fork.
While it’s easy to think we are expecting too much, but if someone is going to say “Get ready to rethink accepted wisdom” they need to be able to accurately measure, monitor, and track every variable between tires under test. While there are many, there are certainly not too many. Nor is exorbitant cost or complexity an issue.
There may be new entrants and new types of testing, I do not think there has been a general upheaval of the framework at the cutting edge. It’s following the same pattern with the same results that has been building for several years.
Simply put, what is different from 2024/2025 that would make this statement correct? Nothing was provided, for either the specific claim or evaluated as whole.
It depends on where those edge cases are happening. I did a race earlier this year on mostly tame gravel. I ran my Race King 2.2’s, mostly because I was too lazy to swap tires for a fun early season race. I honestly thought I’d regret the tire choice at the start line. What I forget about the course was how many loose corners there were all day long, including several in the last quarter mile. The difference in cornering traction/confidence between a 2.2 MTB tire at 18-19psi and a 45mm gravel tire at 25+ psi is huge. And most corners (at least early and late in gravel races) are selection points where people are pushing it as hard as possible trying to break the elastic. At one point, I was on the front going into a corner and not even pushing that hard and about 5 guys in our group slid out trying to make the corner at the same pace. And no, we certainly didn’t wait for them. Whether you call them “edge cases” or not, gravel races are often decided at selection points. Unless you are treating a gravel race like an individual TT, optimizing for selection points can often be better/faster than optimizing for the majority of the race.
The context was a claim that Caracals have more grip than Burts (per the BRR wet grip test). I was simply saying that by that same logic they have more grip than a 2.4” Barzo as well. It was an example to show the irrelevance of the BRR wet grip test as a proxy for offroad grip.
