the thing about eating ice and so on, it’s very good, it thermoregulates your body.
Had to dig up your post about the Roval Rapide front wheel as I compared my front wheels in the velodrome, too and the results…they dont add up to me.
Short disclosure:
All runs were on a Shiv TT Disc in the Augsburg 200m Velodrome at ~ 48km/h and calculated down to 45km/h.
Baseline / Lauf 1 Aerocoach Titan (GP5000TT 25mm with Campagnolo Disc Rotor and hidden valve)
Lauf 5 Enve 5.6 (GP5000 25mm with Shimano SM-RT900 Disc Brake Rotor and about 2cm of valve) → re-calculated as if the Crr was from a GP5000 TT
Lauf 6 Revolver Troika TMD (GP5000 TT 25mm with Shimano SM-RT900 Disc Brake Rotor and about 4cm of valve)
And if the results are to be believed the Enve 5.6 would be marginally faster than the Aerocoach Titan or the Revolver Troika TMD 
. What I got to confess, and the eagle eyed among you will have spotted it:
- The tire width is not optimal for the Titan and the Campagnolo Disc Rotor probably isnt faster than a old Shimano one…probably slower.
- The hideous long valve on my Troika Trispoke might negatively influence the measurement. Additionally its said to perform best in slight crosswinds. At 0deg Revolver material shows that their own Kronostock X is slightly faster.
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While I think the difference between a 5.6/ Rapide and a super deep/ aero wheel like a Titan/ Troika etc. Will bei smaller than one would expect, I think this test really shows the limitations of track vs the Wind Tunnel.
The track can mainly measure at 0 or super low yaw, while you are likely to experience other yaw angles in the real world as well. Deep wheels, and for example disc wheels really start making a difference when the wind comes from the side.
When I tested in Augsburg, one of the guys tested ENVE 7.8 front and back vs ENVE 7.8 front, ENVE disc rear and the former was faster…
Grain of salt for sure.
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Based on the swissside data you really can only expect a difference of around 3w and that’s within the margin of error. Interesting test nevertheless.
Shows how finding the best tire to fit your wheels and not go overly long with your valve stem might matter more than a fancy new wheelset 
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Hmm I just got my new Titan in the mail yesterday and put a DA rotor on it no problem. I was nervous after your post, but now I’m curious as to what your fitment issue was.
The track can mainly measure at 0 or super low yaw, while you are likely to experience other yaw angles in the real world as well. Deep wheels, and for example disc wheels really start making a difference when the wind comes from the side.
Super interesting, is this why I have heard anecdotally that testing position on the track and equipment in the tunnel is often used?
Testing Position on the Track makes a lot of sense.
Firstly, position is usually not that dependent on yaw angle. More importantly, you can test, that you can actually ride at power and speed. Helmets and suits usually function at all yaw angles too, so that’s great in the track. Wheels, fairings, tire widths, and other minimal changes like hand position are usually really tough to measure or make hardly and difference at zero yaw. Hence, measuring them in a wind tunnel makes more sense.
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Why are devices like Notio, Velocomp etc that help you with outside testing (ideally on course) not more popular then?
Seems like that would be the most accurate and also cheaper (compares to repeated aero testing in the velodrome)
From my experience with Notio:
I found it really difficult to get reliable data, with hedges, trees etc. creating turbulence in the wind. The Notio will calculate stupidly high or low CdA values, which we had to sort out manually.
But it can be done.
The biggest issue I had was the software. It’s the worst thing I’ve ever used.
The problem really is, that conditions outside are not consistent, and it is difficult to pinpoint where the wind really comes from, if you really traveled the same distance and many other factors.
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I can confirm this as someone who bought a Notio, too.
- The App is annoying and still, after so many years, only available for iOS.
- The Golden Cheetah plugin is okayish…not the most user friendly but you can get it to work.
- And thats not the Notios fault, but generally outside testing: Stuff changes…Comparing Day 1 to Day 2 results doesnt work and even on same day testing you can run into troubles from the wind picking up or changing direction.
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Also road surface can cause discrepancies in the data and there is no way to mitigate/adjust for it. eg if your route changes from a rough to smooth tarmac partway through, it won’t be able to tell the difference. But you will obviously go slower/work harder on the rougher surface, so the software will assume you are less aero - it was actually the rolling resistance slowing you down, not the wind resistance. For a single run it’s not a problem, but if over multiple runs you have some with more wind on the rougher section and others with less, the accuracy of any results will drop way off.
Basically aero testing is subject to many variables, most of which are difficult/impossible to measure and even more difficult/impossible to control. Wind tunnels are by far the best environment for aero testing, as they offer the lowest number of variables and the greatest amount of control.
Off topic: you recon this is stupid to put the bottle as a fairing even though I never tested it, or you recon it is likely faster?
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You’ll have an easy excuse if you’re slower…
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Bummer to hear the app/UX is so frustrating.
I have a few different segments that are somewhat flat, along or through a forest and barely any cars - doing repeats for testing back-to-back should be 80% there, but was hoping Notio or other devices would help to eliminate the wind variable.
Not reliable to compare across days obviously.
Decided against the bottle, and had a blast at the TT this weekend. Great course, with a few hills, good weather and strong competition.
Ended up 4th overall and won my age group (ironically Men‘s Elite 
). 2 masters riders were about 20 to 30 seconds faster while the overall winner, a user on this forum too, completely obliterated everyone by a country Mile.
Still very happy with the result. Felt like a good prep for King of the Lake in 2 weeks time.
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Shocked by the empty space below my torso.
Looking at the British cycling champs, where basically everyone had a chest fairing, I think I might really benefit from it:
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The “chest fairing” has been in use for years in longer TTs where it’s the most convenient place to store hydration (at least without a frame with an integrated bladder), and people have always done wacky things in CTT events with it’s more relaxed regulations.
But I’d draw the line at inflating a hydration bladder (Dowsett had a video of himself doing this before the start of a 10 mile TT) and carrying two empty bottles behind the saddle!
The problem now is that if the guys on the podium at the national 10 are doing this, then the guys who aren’t on the podium are going to have to follow suit to be competitive!
It’s going to be very hot for my 25 mile TT Sunday. Not sure I need hydration for a 50 minute ride (hopefully more like a 48 minute ride 
) but I may freeze some water in a bladder for the race, and then I’ll have a drink ready for the finish line.
I wouldn’t want a frozen bottle on my bare skin, but I understand the idea.
I’ll definitely try it out and see what gives.
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Some initial testing done by Jim @ ERO indicates that it is faster….but as usual, the answer is “it depends”
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For the none UK TT’er that didn’t see.
Last weekend at the 10-mile National championships some of the body fairings were pretty extreme.
Probably going to be some rule changes coming in next year around this.
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