I’m inclined to think they may have used 25c. Enve does best with 25c while DT/SwissSide does best with with 23c. If they used 23c, then kudos to Enve
While Enve claims the 25c does best, the old aero shootout we did would seem to indicate otherwise, at least with the tire we (I) selected.
Tom, I know this is likely answered before, but is enve’s claim on the newer SES rims that 25 works best an absolute measirement? Or 25mm on the Gp4000? Only reason I’m asking is that the bike I have on the way has specced enve disc SES wheels but comes standard with Gp4000 25 tires, while I know the Gp4000 run large.
Should I be choosing 25mm gp5000 going forward? Or something that is slightly larger than 25mm?
First off, I would not base a couple of wind tunnel tests we did as the holy grail. If there is anything I learned from the second time at the tunnel with Brian and Heath (they helped with the actual protocol), it is that wow, small changes with tires (think heating up of the tire and slightly expanded tire via increased pressure) can cause pretty drastic changes. I think part of why I wanted to do it was because of transparency. I always admired industry white papers. What I would have liked to see when Enve, or anyone for that matter, makes claims is to show the data. Show how many runs and what they had to do to make something true. Was the 23mm inflated to 120 psi but the 25mm at 60 psi?
At the end of the day unless your livelihood is made racing I would say go with whatever gives you the most confidence. The 25mm is still a fine choice and who knows, when you factor in the fork, and your PSI, and the tire, and rolling resistance, and handling, well, it maybe be the fastest option.
I think its also important to note that the the Roval 50 series was tested as CL and Not CLX which has the aero spokes…this would have most likely offered a strong differentiator from the “pack”…The 64 was the CLX
The CL doesn’t have aero spokes? Are you sure about that? Did they make a production change at some point. I thought the only difference between the CL and CLX was the ceramic bearings.
I think its also important to note that the the Roval 50 series was tested as CL and Not CLX which has the aero spokes…this would have most likely offered a strong differentiator from the “pack”…The 64 was the CLX
The CL doesn’t have aero spokes? Are you sure about that? Did they make a production change at some point. I thought the only difference between the CL and CLX was the ceramic bearings.
Absolutely positive. I designed them 
CL to CLX is ceramic bearings and aero spokes for this generation of Roval Road (32/50/64)
In real life though & ymmv, I sort of think that the 2-3w range is noise as much as difference. Now am I going to select something that is 3w faster from tunnel testing? Absolutely 2w? IDK, let me think and it also depends what part of the human/bike machine that 2w comes from.
Good point.
To add to that: it seems to me that the difference between most comparable wheels is probably lower than the variance introduced by testing protocols, wind tunnel accuracy, etc. - that’s my take-away from looking at various aero tests where one brand is sometimes better in one test, and poorer in another: but not by much.
And not to refer too much to everyone’s favorite maker of BB brackets and aerodynamics expert, but Hambini did have a good point that real world conditions (gusty) add a level of variation to performance that cannot really be replicated in the steady state flow of a wind tunnel. For sure, I would guess that the error margin introduced by this would be an order of magnitude higher than the vanishingly small difference between 2 wheels of more or less similar rim size and shape.
At this point, I have decided not to obsess about aerodynamic differences between various brands too much, but to focus on other attributes like stiffness, weight and price. Oh yeah, and how well the logos match my bike (the MOST important thing, of course).
It would be interesting to take the hunt data, and see iff/how the pecking order changes in non steady state. It would be a dirty way to see how comparable performance is in each protocol.