Thanks for testing these! I’m guessing that the Cda differences will make the overall drag between the Caracal and TB closer on Cat 1 gravel? Which overall package was faster?
Ah, good question. I’ll work on that today.
ENVE 3.4……and I have a set of Alex rims / DT 240’s that are narrower that I’ll try if they don’t work.
Worst case scenario is I run my Thundero 48 on the back.
While not a crux, my mosaic GT-1 45 is rated for 45mm (has measured 6mm clearance with a 45mm tire). With my TB on a 27mm IR wheel, it measures around 53/53.5. It doesn’t rub free wheeling in the rear, but absolutely can when putting power down. I can see the brushed titanium has some wear marks. I’m fine running it with a metal frame but it’d probably tear up carbon pretty quick.
Saturday will be my first time running the TB up front and the 47 pathfinder in back. I’m optimistic that it will be a good setup for comfort/speed/puncture resistance.
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You are braver than me 
Curious to hear your experience!
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Nice! That should be a good setup. FWIW I really like conti terra speeds and they measure a true 45mm for me - if the pathfinders don’t work out.
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Braver or dumber? We’ll find out! 
ETA - looks like I have 4-5mm between my Thundero 48’s and the chainstays. It is gonna be TIGHT when I mount the 2.1’s!
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Now I have to figure out if the .0006 crr on tarmac, makes up for the .0007 on cat 1 gravel plus any aero benefit of the thinner tire on a deep wheel.
Yes, I know people will reference this post when they need an example of how ridiculous cyclists are. Oh well.
Shoutout to @jsiegrist for shipping these Caracal Race 40s across the country just so I could test them properly. Much appreciated!
Anyway… I put them through it.
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Happy to help and really interesting results. Thanks for doing the work!
Have you done any comparative aero testing? Seems like a cat 1 gravel course that’s 50/50 tarmac these caracals are maybe still the right choice vs a 2.1 burt?
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Yes I base lined CdA values for these vs Thunder Burt 2.1s.
Caracals very viable option for that scenario.
More soon, test wheels arrive tomorrow.
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Cool cool. Sorry to jump the gun. 
Will you post a picture of what you are considering Cat 3 Gravel? Your Cat 2 Gravel looks like soft dirt, so I’m thinking your Cat 3 Gravel is probably what most of the trails I ride on look like
Pic is in this IG post
The Cat 2 is dirt road that cars can’t access. Loose gravel over dirt and some leaf cover in some places. It’s generally very representative of a “regular” gravel section. I’ve ridden it on down to a 35 mm tire.
The Cat 3 is definitely mtb territory.
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Hadn’t seen the latest data that included the Aspen on the Cat 3…
That one is very interesting because everyone tips on the Maxxis for making such slow tires…but it seems like once it gets rougher and extra volume of the Aspen really seems to help. Marginally slower than the Thunderburt, which on other surfaces tests faster than the RK - is it possible that the Aspen might test faster than the RK on Cat 3 for you?
DJ might completely write you off if you suggest that and Aspen is a comparable or faster MTB tire than the RK 
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And yet, at least @jkarrasch is bringing real roll down data! I wonder if DJ would produce some of his own roll down data from the rides he’s hinted at in Brevard when he’s done his own testing…
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Yeah there are probably a few methods of rolling resistance testing. My courses def have some up and down in them. The cat 2 one is has around 180 feet of climbing for 3 miles of laps.
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That’s interesting, but odd. I wonder why the 2.1 Super Race tested so slow on BRR.
Looks like the 2.1 Super Ground 'Burt is gaining momentum on BRR, should win either this month or next month. We’ll finally get a like-for-like comparison.
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The Super Ground vs Super Race in the same tire and size will be interesting. Schwalbe themselves still claim the Super Race as the faster tire. My only concern would be year to year variation in the tires given the prior reports of some inconsistency with Schwalbe tires.
Separately, there has been lots of discussion regarding the 2.1 TB as a fast option for gravel. The 2.1 size squeezes into a number of popular gravel bike frames. However, for bikes that have proper clearance for a 2.25 (ie rated for it), would there be any reason to not run the 2.25 TB in that case? This is assuming it would be used for a course that is primarily gravel and not primarily road.
That’s the logic I used to go 2.25 on mine. Real world width isn’t much different. Mine measure 2.10-2.15in on 25mm rims. 2.1s on my wife’s 25mm rims measure more like 2.0s.