Generally agree (particularly when the road/gravel gets rougher and speeds get lower), but it obviously depends on how big the rolling resistance difference is vs. the amount of the aero penalty. Like most of this stuff, it’s highly dependent on course, speeds, and strengths/weaknesses of the tires being used. I recently tested a front race king vs. a front pathfinder pro and the pathfinder pro was a bit slower on a mixed surface course. Rolling resistance of pathfinder tests slower, but it was faster. I’d attribute that to being ~9mm narrower and more aero.
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It wasn’t a point about the balance point for CdA against Crr in isolation; this topic has formed much of this entire thread and is pretty heavily written into.
It was more about the (perhaps not examined) issue of unequal distributions of CdA and Crr front tyre to rear tyre - especially for those running a wider front.
The only source I can find for 70/30 for Crr is Continental’s head of tyres on a Road.cc article. Maybe he pulled it out of his backside. Silca quotes 47/53, but let’s be honest - anyone that has ridden for more than a few hundred miles can see that the wear to a rear tyre is more than 12% rear focused - it’s night and day. That said, i had a pretty indepth google and can’t find much beyond this.
It would seem to me that there could be an argument to run the widest and fastest rear you can fit in your frame without puncturing, then the most narrow (or, well, rim matched) front tyre you can run without crashing 
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No misunderstanding, had just moved on to additional discussion. And totally agree that wider probably has more rolling resistance benefits in the rear without as much aero penalty. But many bikes have more limited clearance in the rear so people tend to run a staggered setup. I look at the front on it’s own and there are certainly cases where larger makes sense with lower rolling resistance and better handling trumping aero losses. Would there be cases where you run larger in the rear and smaller in the front? Maybe, but if a road is rough enough to favor a wider tire, it’s often going to favor it front and back and having a grippier tire in the rear (compared to front) can also cause some handling challenges (ie- crashes).
edit - I wouldn’t read too much into tire wear as an indicator of rolling resistance percentage. Sure, some of that wear is related to weight and corresponds to Crr, but mostly they were faster because the rear is the drive wheel. Drive wheels always wear faster whether they are carrying more or less of the load compared to non-drive wheels.
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Haven’t read that one but I’d wager they then referred not to a crr distribution but a resistance/watts lost distribution. That would make sense as the resistance is crr times load on the respective tire. So in a typical road bike weight distribution on the flats it’s somewhat 40 %'ish of total weight on front and 60’ish on rear tire? Some tire pressure calculators even let you take this into account for their recommendations.
That would then give you the answer you were looking for. But it will change on rider position on the respective bike and whether on flats, up- or down hills.
Wasn’t planning this at all, but landed a spot for Cat 4 Gravel Chung Method testing today.
It’s pretty sketchy, so not putting it in the regular test course rotation but definitely interesting.
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Excellent, very interesting. Did you manage to ride the course without braking? That must be tricky, as well as the challenge of repeating the same line.
Interesting stuff yet again.
The Thunder Burt jumped by 0.0066 CRR from cat 2 to cat 3, and by 0.0035 from 3 to 4. In comparison, both of the 2.4" tires only jumped by 0.0037 from 2 to 3. Assuming that ratio stays constant would lead to a CRR of 0.0175 for the Peyote and 0.0189 for the Aspen on cat 4, in comparison to the 0.0202 of the Thunder Burt.
That seems reasonable on such a chunky course.
UK grade 1. Nice
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Correct no braking. Took a few tries to get length correct on it!
Nin that sounds quite reasonable to me.
Apparently Maxxis is coming out with something new in April 10th. The good news for them is that the expectations for a good rolling resistance is pretty low…
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I know the picture is very fuzzy but these don’t look like huge MTB tires lol
Curious what they are!
My assumption is a new gravel tire in the 50mm range. A 50 rambler? If so, no one is going to care that isn’t paid to ride their tires.
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If you need further proof that no one cares… The 50mm Rambler has been out for years… hahaha…
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Maxxis heard that a MTB tire is the fastest and best tire for gravel racing so went all in with DHF/DHR for gravel! 
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I’m convinced the tires Maxxis supplies their pro riders with are not the same tires available to us consumers. Every Maxxis tire I’ve ever put on my MTB has felt incredibly slow, even tires like the Rekon Race or Aspen.
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Ha! I was thinking, I’m pretty sure my wife’s e-bike came with 700x50 Ramblers. Got home and checked and sure enough, it did.
I understand these tests kind of leave a lot out for a MTB tire, but when we’re talking about gravel… I just don’t understand on the Maxxis tire has lower center knobs, is heavier, and has significantly worse rolling resistance. Having spent a few hundred miles on both tires (on singletrack), I feel like they both corner terribly, but the Conti is noticeably faster rolling. For gravel, I just don’t see why I would run a Maxxis.