I don’t normally pay much attention to speeds when doing Chung testing, so I went back and had a look at the data. The average speeds were around 15 mph (see below) but it varied across each 6-lap test because varying the power and speed can often be insightful when doing Chung method testing. Grass is probably slower than gravel, even though the underlying ground was dry and hard, and slower than your Pathfinder/RK tests that you described earlier. With hindsight though, and if I did this kind of Bike A vs Bike B test in the future, I would try to ride at typical race speeds because that’s probably important when trying to find the net effect of aero and rolling resistance changes (since rolling resistance power losses vary with speed, and aero power losses vary with speed cubed).
This was quite a quick and dirty test, not done on the same day, and with different power meters, so that’s another caveat worth keeping in mind with this result. I did my best to correct for PM differences, but I’d like to test this again at some point, on the same bike, same PM, same day, with ABAB type repeats, to isolate only the tyre effect. Gravel would be interesting to test too, but it’s more tricky to find a suitable gravel loop near me that’s not filled with dog walkers.
Mine are advertised as Gravel too, but “cross listed” for XC (We Are One Revive) - and I have them built with Berd Spokes. Just call or email Berd and ask them why specifically. It could be that it’s just a general recommendation.
(Also, these are a marathon wheelset for me where light weight matters, I have another every day set for the bike)
BRR is always sus in my opinion. I have no proof, but the amount of Schwalbe tires that dominate seems wild.
I’m in the midwest and currently try and run 700 x 40 Maxxis Receptors as much as possible because they are fast. I moved from 38c Gravel King SS, which for some reason felt more draggy. Plus they sucked to set up tubeless.
If I need more traction I’ll run 700 x 45 Maxxis Ramblers. If I need more flotation for whatever I run 27.5 x 2.0 Specialized Fast Traks. Which honestly are way faster than they should be.
Plus I mean, drop bar gravel bikes with MTB tires just look rad.
Take the rubber/casing names with a grain of salt.
The Superground looks to mean they use an e-bike friendly and more rim/snakebite proective casing. Schwalbe , at face value, looks to build MTB tires and Gravel tires the same, but the Gravel tire might be made more durable because of the higher off road tire pressures.
On the BRR tests, they use a textured surface that doesn’t agree with some tread patterns and the pressures on the MTB test aren’t realistic at face value (if you’re comparing medium to medium).
Anyway, go Superrace if the brown sidewalls agree with your bikes paint.
I had the same predicament, trying to decide between the Super Race and the Super Ground version after seeing those BRR test results for the Racing Ralph. In the end, I decided to go with the Super Race version. I’m hoping that those strange BRR results for the Ralph are the result of some manufacturing teething problems and inconsistencies, not too long after the introduction of those new casings. It’s certainly Schwalbe’s intention and their belief that the Super Race version is faster rolling. Those BRR tests create some doubt about which casing is fastest, though.
If you’re able to buy both versions and do you own testing, that would be best and the most rigorous way to be sure which version is fastest. In fact, when I did my own roller testing of the Super Race Thunder Burt versus the Conti RK, I also had a Super Ground version of TB that I wanted to test too. Unfortunately I couldn’t get the Super Ground tyre it onto my rim (a Stans Crest), despite wrestling with it for half an hour. The Super Race was very tight, but do-able. I gave up with it and returned the Super Ground version for a refund.