i meant minimize / negate a part of it
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I just wish they were a bit more clear on their testing procedure. I can’t find how they weight their yaw angles and each bike has different bar widths, tyres and wheels. You could make the top 30 bikes move around quite a bit just by altering those. For example, the Orbea Orca aero tests at a slow 212 watts, but it has slow wheels, tyres and a massive 42 cm non-integrated handlebar. Put its aero bottle on (takes it down to 209 watts), modern one piece narrow cockpit, Dt Swiss di cut 62 mm with gp5000 tyres and it could well be in the 206 or below range. Because they don’t test with a fully dummy, the front wheel and handlebar disproportionately have more effect. Although it is still a heavy bike.
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AFAIK they don’t publish their angles. Also do you really think bar width tested without a rider would alter testing much? Think about if you have a skinny aero bar that’s 36cm wide vs even 44cm, because it’s so skinny top to bottom you’re really not adding a lot of frontal area that hits the wind. Sure the shifters are further out but they are the same size. If we were comparing a 36cm vs 44cm round bar, I’d agree and if you test the 36 vs 44 with a rider ON, and you’re gonna see some changes for sure.
I think between modern aero or semi aero bikes you’ll notice more of a difference in comfort and handling and stuff but they’re all fairly close for most people. I do think if you’re coming from a bike from 10 years ago then yes you’ll def feel a difference. My Madone is just objectively fast, even going out for an endurance ride it just always feels like it wants to go another gear harder and if the road points down just a little it’s a rocket
My first ride on my new Aero road bike and modern wheel/tires. I am fairly impressed.
Road condition - worn/bumpy
Wind conditions - 12mph NNE @ 6pm fading to 5mph N @ 7pm
Course direction - south counter clockwise to starting point
Riders - (3) riders in pulling/breakaway formation with (1) rider along for the ride.
Perceived pulls/front effort - 35-40% of ride
I wish we could have caught that fast tailwind ride home 
I will say, I feel very slippery on this bike - the bike simply fits me very well. I spent a lot of time finding a good geometry/fit for me.
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I definitely do. With no human/mannequin body, the front of the bikes makes up most of the A and cd. Even different brands of tyres will alter the result Look at how fast the systemsix is as it uses a 64 mm rim and a weird old Vittoria tyre in 23 mm, if you plonk a Shimano wheel on with a 25 mm tyre it will likely be slower. Also SL7 vs SL8 difference is a lot to do with the new handlebar. When they tested the r5, it got 6 watts faster with a zipp wheel.
Regarding the bar, I’m on about comparing a 2 piece 42 cm bar (as on the Orbea) vs the one piece narrow Specialized bar. Put that on the Orbea it will perform better. If Tour results impact sales, I am really surprised at companies stocking the bike with poor aero parts.
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I think the tires impact it more due to how they change the airflow interaction with the wheel especially at any kind of yaw outside of 0, but who knows. I don’t think Tour really impacts sales too much, they are probably not even known by most cyclists who just walk into a store and buy whatever frame or color looks nice. People like us are a small niche of the buyers IMO
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Supersize Evo (road bike) vs Crux (cyclocross bike) is hardly real world. Different geometry, different position on bike, probably deeper section rims. Rider position (e.g. hands on hoods, flatter back/profile, arms parallel to road) are probably baked into the design of the Evo. Crux is optimized differently in terms of stack, reach, BB height) than road bikes. A “non-aero” road frame geometry bike would probably also have improved your crux PRs. Add some deeper dish wheels , and flatter bar…Adding an aero helmet will save ya 6W at 20mph. Now slightly wider tires and lower pressure. It all adds up, but an aero frameset is a very marginal gain compared to other factors. There are other factors we haven’t studied, like vibration/ compliance on the road surface. But just ride whichever bike you like the most. A well fit, comfortable bike will always produce more watts than a wind tunnel tested frameset.
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Sorry to be confusing. Thread was about aero bikes, not cross bikes vs road bikes for road. It does all add up, but an “aero frameset” is actually a very expensive drop in the bucket c/w other upgrades. As a shop owner and bike builder, I see time and time again people who are slow and uncomfortable on the road on their $12k, wind tunnel tested, TDF-proven road bikes with 4cm of spacers under the aero stem to try and get comfortable on a bike built to be riding solo in a time trial. Making size adjustments to these (seem, bars, etc is laborious and time consuming). Traveling with the bikes is tough because of the integration. To some extent, it is the industry’s way of keeping people buying by selling dreams. There are a lot of factors that we don’t have the metrics to capture, either.
My own anecdote: when I started building custom Ti bikes, my first “experiment” was to build the exact facsimile of an aero road bike I’d raced and loved for years in titanium to see what the difference was in material. Identical geometry, EVERYTHING in the build kit was identical (drivetrain, wheels, etc) only one was monocoque carbon aero shaped tubes, the other round tube Ti. The verdict? Something about Ti seems to carry speed over the road. I’m faster on segments I do all the time, and on longer 100-200mi outings I’m faster and more comfortable. Clearly it isn’t more aero, but there are factors at play here (road dampening, vibration, and some sort of energy rebound) that doesn’t occur with carbon but we’ve no way to objectively measure because wind tunnels don’t have hills, rough surfaces, or measure how the bike responds to power outputs from the rider.
Anyhoo Miles. If you love your bike that’s all that matters. Sounds like it’s set up well and comfortable for ya. Keep riding it!
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If you trace back how most “innovations” in the cycling world begin nowadays, it comes from the marketing department or a (non-technical) product manager. Then Tour comes around and quantifies these innovations with “empirical data”, which you can then rank bikes from 1-100 with. Before aero was mainstream, their focus was stiffness tests, and stiffness to weight ratios.
So there’s zero doubt they are marketing, but that’s not to say that the data is useless. Validating some of this data to show how progress is across the whole bike industry adds value, but a few watts here and there under their testing protocol is within the margin of error and likely isn’t going to make or break your race (more than other factors). People make purchase decisions based on what speaks to them, whether or not they translate into real world performance is how the rider reacts to the whole set of compromises created due to equipment choice.
I clearly won’t change your mind, and don’t need to. At some point, try a road-specific, light handbuilt titanium bike and compare to your favorite steed. One of us has done this. It is worthy of consideration.
If you’re ever in Seattle, we can do just that.
Thanks for the discourse, I always learn something.
you two are debating which broscience is more valid.
do aero frames test faster in wind tunnels? yes.
does this translate to the real world? depends.
I’m not a subscriber of Tour Magazine but what I’ve gathered about their tests is that they test a specific frame size with stock wheels and then again with their control wheels. How do they control for stack height? Do they remove all the spacers from endurance bikes and add a bunch to aero bikes? Do they have a test-cockpit or stem/bar combo or just test what’s being sold as stock?
Aerodrag of a cyclist is 80/20 rider/bike so if you maxed out the body position part, clothing, helmet, shaved legs, overshoes then maybe the aero bike does make a difference. I don’t know if it’s in the realm of 20-30W though… maybe it’s more for some and less for others but saying X frame is Y Watts amount faster than Z frame without factoring in the rider and the position they’d be in is a bit broad imho.
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I’m not sure that they do impact sales, but I’m also not convinced I want to buy an aero bike from a company that makes poor aero choices! I think it’s valid to compare stock bikes as most people don’t buy a brand new aero bike and then immediately start swapping over wheels and bars (especially if there’s an integrated bar). So if a company is selling an aero bike with 42mm wide bars and <50mm deep wheels that tells me they’re not that serious about actually helping their customers to get more aero.
I have done this. In fact my custom ti road frame was even made in Seattle and while it is fantastic riding/handling bike my carbon aero road bike is definitely faster and handles every bit as well.
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True but dt swiss wheels and 25 mm tyres will perform faster in a wind tunnel, most people will be annoyed with those as stock as the trend is wider tyres.
I could knock 5 to 10 watts off the orbea orca aero by swapping to the bars and wheels the simplon has.
Is there any physics reason why adding an upper body to the equation would change results, given that the upper body is in identical position for both bikes being compared?
Serious question, I don’t know physics, I do understand that pieces added can have very different aerodynamic effects than the individual parts, but adding the exact same thing on top of something like a bike, not sure you’d suddenly see a bike that was 20w slower without the upper body catch up with the upper body added.
It seems like adding the body will make the percentage change between two bikes smaller. Maybe they want to do that to keep the differences between bikes more based in reality?
I looked at the Tour mag tests a couple of years ago. The 100km simulation test stood out to me. One is saving like 3-4 minutes over a 100km/66mi from the best to worst bike. That tells me that once you are in the top 10 or even top 20 bikes the overall differences are going to be small. Even Pogacar can win everything on a Colango all-arounder bike which isn’t the most aero bike in existence.
I’m not saying that aero isn’t real. It certainly is but you aren’t getting much by ‘upgrading’ from a Tarmac SL7 to an SL8. A handful of theoretical watts is hardly anything.
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I’d head over to the Rule 28 aqa thread for your answers and maybe a better place for your questions. Early on the guy from Rule 28 listed a hierarchy of aero gains starting with biggest being kit and with the last and least being a frame. They seem to spend a lot of time in the wind tunnel testing their clothes so they would have good insight as to why an aero frame may be of least concern.
to add on to that: someone recently posted a study about repeatability of aero positions on, was it, track cyclists? In principle track cyclists were to do laps in a velodrome and were tasked to hold the same position for each lap. Some participants were really good, others were way off and the positions had a standard deviation of couple of Watts.
Is it though? As I said, I’m not a Tour magazine subscriber but assuming they test stock bikes with stock components it would surprise me if they equalize for stack height and cut test bikes steerers to try to equalize frontal area. If a 56cm aero frame with 550mm stack and a 360mm handlebar tests 30W faster than a 56cm endurance frame with 580mm stack and 420mm handlebar what does that tell you? It tells you that reducing your frontal area is more aero… in other news, water is wet.
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This is fascinating and actually a very good point - if seeking to identify whether a particular ‘frame’ is more aero than another in isolation.
I presume to be balanced and ‘fair’ in any assessment of just the difference between actual frames, you’d need to have the same width / style bars at the very least..
You could (possibly) argue that because stack height is inherent to the actual frame that it’s a fair enough in a like-for-lile comparison, albeit the comment already made serves well in explaining an obvious observation that greater overall frontal area (even if quite minor) is likely to present a greater drag.
I imagine back to back bike tests would be most often be comparing similar bikes (so aero frame versus aero frame as opposed to aero frame versus comfort frame?).
So fitting the same or similar bars (if offered) might lead to a more accurate test.
I guess the fair counter argument here is that bike manufacturers offer their bars / frames etc as a ‘system’ so the average buyer is going to get what their given unless high levels of personalisation are available?
Good food for thought indeed 
Considering that for most aerobikes the cockpit is integrated and sometimes totally proprietary and can cost a lot to replace. It is only fair to test with the Cockpit they come with.
The doubt that roundtube bikes are significantly slower then aerobikes is hilarious there is so much testing out there… If the gains are worth it for someone is another question and a personal decision.
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