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i ride HED Ardenes +, and Pacenti SL23

both on decidedly NON-AERO frames. Look 585 and Ridley Damocles.

what kind of difference will i experience with, say, Reynolds Aero 46?

will it be like waking up from a nightmare?
 

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will they take me from B+ to A group?
Yeah maybe if the A group is normally closer than about 100 meters away after both of you going flat out for 50km. Otherwise, you won't notice a hill o' beans of difference. And that's if those wheels are lots more "aero" than what you now have. They might be worse. You can't tell by looking so book time in a wind tunnel.

will it be like waking up from a nightmare?
Nope and your nightmare might be in the form of some kid passing you in the last 50 meters of a balls-out race while riding a POS $700 bike with house-brick shaped rims.
 

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Aero wheels are faster, but they almost certainly won't take you from B to A unless you are close to already and most of the riding is at speeds over 25mph. I find the difference is quite noticable around 30 which I'm not going to hold for long as the lead, but it's fun while I do!
 

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Like most things in biking, it all depends on the condition of the engine. I love perusing classifieds for wheels and at least 1/2 of the aero wheels mention how "fast" the wheels are. I always wonder how is it that wheels can be fast? They don't go anywhere unless someone gets on the bike and starts pedaling!
 

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The objective answer to your topic question is that they categorically will not take you from the B+ group to the A group. Let's take your HED Ardennes+ as the "control" sample, and we'll substitute in a 45mm deep Zipp Firecrest 303 for the Reynolds Aero 46. The widest difference seen between those two in the wind tunnel, at 30mph, is 11 watts. That occurs at 12.5* yaw angle, which according to the most credible data accumulated is a condition which occurs roughly 4% of the time. During the approximately 80% of the time in which your yaw angle is 5* or less, there will be between zero and two watts of advantage to the 303 over the HED.

Since your construct is a group ride, you will be drafting. Drafting cuts the benefit of aerodynamics by about a third, for starters. So approximately 80% of the time, you will be benefitting about 70% of zero to two watts.

There are bigger aerodynamic gains all around. Better clothing fit is basically free and is a bigger gain, for example. Tire and tube (or not tube) choice can have a much bigger impact than aerodynamics, and occurs at all yaw angles, whether you are drafting or not.

In terms specific to your quest for making it from the B+ to the A group, working on riding skills and specific fitness things will be of exponentially greater help than anything you'd buy. Most A group riders drafting skills somewhere between "sort of competent" and "absolute invisible ninja." The pace of an A group is more demanding and will expose flaws in your drafting skills more readily. Learning to pull off the front while you still have plenty of gas left to get back onto the train (the hardest part of a pace line) will give you a big gain. Learning to anticipate, when to leave space to the rider ahead and when not to, will have huge benefits.

There is also the downside that deeper wheels bring, which is their handling demands. A rider in your situation has much more to gain from having absolutely zero drama wheel handling than 0 to 2 watts of aerodynamic speed.

There are a lot of things that good wheels can do for you. Taking you from the B+ group to the A is not among them.
 

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The first time I tried deep aero wheels I rode my wheels (Hed C2/DA Hubs) about 25 miles to a shop that was lending them to me to try. I mention the ride on my wheels to get there just to highlight that it was a back to back compare.
The wheels were tubular Corimas. Don't quote me on this but at the time I think they were about $4,000 and certain tests said they were the most aero on the planet.

My first impression was: Nothing. Felt just like the wheels I just got off.

My second impression was: Thank fck I tried these and saved myself some money I would have wasted. (I wouldn't have bought those $4000 wheels but probably would have sprung for a $2000ish pair)

Perhaps a power meter and a controlled environment would have told another story but anecdotally I couldn't tell any difference in speed or anything for that matter.
Actually there was one difference, to my surprise the braking was actually better on the carbon rims as compared to my alloy rims. It was a dry day though.
 

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Most A group riders drafting skills somewhere between "sort of competent" and "absolute invisible ninja." The pace of an A group is more demanding and will expose flaws in your drafting skills more readily. Learning to pull off the front while you still have plenty of gas left to get back onto the train (the hardest part of a pace line) will give you a big gain. Learning to anticipate, when to leave space to the rider ahead and when not to, will have huge benefits.
^^^^ This.
Hanging with the A group is about drafting. And climbing, if you live in a hilly area (which aero wheels won't help).
If you take too long of a front pull in a pace line, you're done. The train will pass you by and aero wheels won't catch you up. Get gaped off the back and you're done. Aero wheels won't catch you up.

Work on some interval training. Being able to sprint in short bursts and recover quick will help you hang much better.
 

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There were two main (and massive) differences that stand out when I had a set of 50mm deep carbon rimmed wheels for a whole "summer" season -

1) Wet weather braking was dangerously bad. And that was with the pads that were supposed to be used with that rim.

2) Strong crosswinds were just as dangerous. I took them off right after I got home from this - while descending a shortish 30-35mph hill, a truck passed me and took away the wind I was leaning on. And I was expecting it too. That moved me over almost the whole width of my lane. I could have gone under the wheels of that dumptruck or gotten hit by a following car. I can only imagine the devastation if I was with a group of other riders.

And to top it off, my well-kept average speed data didn't improve above my years of data on 19-24 & 30mm deep rims.

Yeah all this is far more anecdotal than Dave's techie response but it was good enough for me.

Effects on other deep rims may vary. Others' experiences may vary. Yada-yada.
 

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Corima tubulars have other-worldly dry braking. Their molding technique is fantastic and their cored construction means the brake pads are hitting what feels like a very smooth still I-beam. There is no squish. In the wet, it's still a carbon rim where you can only use one type of pad.
 

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Corima tubulars have other-worldly dry braking. Their molding technique is fantastic and their cored construction means the brake pads are hitting what feels like a very smooth still I-beam. There is no squish. In the wet, it's still a carbon rim where you can only use one type of pad.
Carbon clincher rims for us amateur cyclists is a (very expensive) step in the wrong direction. Carbon tubular rims for pro road racers is a whole other scenario.
 

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Carbon clincher rims for us amateur cyclists is a (very expensive) step in the wrong direction. Carbon tubular rims for pro road racers is a whole other scenario.
He was responding to something I said. Not suggesting those were a good idea for anyone likely to read this thread (just incase that's what you thought)
 

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46 isn't so bad, but for sure aero wheels can take you right off of the road. Or into it.

They very much can catch crosswinds, bad enough for you to be blown right into a passing car, or blown off of the road, or tossed around enough to crash without hitting anything.

I won't ride anything deeper than 50mm in the front, no matter how good the shape is. The wind is a powerful force not to be messed with.


And no wheels will allow you to keep up with the fast group, but altering your position could without question. Learn to live down in the drops and as aero as possible if you really want to go fast.
 

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He was responding to something I said. Not suggesting those were a good idea for anyone likely to read this thread (just incase that's what you thought)
Yes, absolutely, thanks. People don't offer consider that a "X" tubular is likely more like "Z" tubular than it is like "X" clincher. This perception that because some pro rides a certain tubular is proof of concept of the clincher version of that tubular is a fallacy. The fundamental differences between tubulars and clinchers is just so vast. Which is not a pro- or anti- tubulars or clinchers statement, but just a statement of fact as it is clear to me spending 99% of my life around bike wheels. But structurally, the tubular tire system is so much kinder to the wheel that it's almost laughable. We're rebuilding a 303 tubular for a customer this week (updating old hub to 11s), and without a tire on it, it had literally zero non-drive tension when it came in the door. A clincher wouldn't last a week like that without becoming unrideable.
 

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He was responding to something I said. Not suggesting those were a good idea for anyone likely to read this thread (just incase that's what you thought)
S'awright. I was just commenting on carbon rims (especially clincher rims) in general. I thought that was obvious. That's why my sentence started with 3 generic catch-all words and never mentioned the C-Word rims at all.

I think we're still allowed to comment around here.
 

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Let's take your HED Ardennes+ as the "control" sample, and we'll substitute in a 45mm deep Zipp Firecrest 303 for the Reynolds Aero 46. The widest difference seen between those two in the wind tunnel, at 30mph, is 11 watts. That occurs at 12.5* yaw angle, which according to the most credible data accumulated is a condition which occurs roughly 4% of the time. During the approximately 80% of the time in which your yaw angle is 5* or less, there will be between zero and two watts of advantage to the 303 over the HED.
Dave, appreciate all of the data you share. Averages are averages, so it definitely comes down to where and how you ride. Last night was typical group ride for Spring/Summer we averaged 22mph into a 20mph wind for about 15 miles before turning and flying home at 25-30mph. Those averages don't really tell the story.

The most windy sections typically have yaw angles of 10-20 degrees, and I spend about 40 minutes on a 90 minute ride in those conditions before turning at the river and catching a nice tailwind home.

Last night on the windiest stretch of 4 mile road, where open fields are below the road and there is nothing to blunt the wind, we were at ~14 degrees of yaw. Drafting the stronger riders, in my best aero position, required 280W to maintain 21.2mph. That is slightly above my FTP. So its not surprising that even a 10W aero advantage from wheels, in those conditions, has made a noticeable difference on being able to hang with the lead group versus getting dropped.
 

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The point of Aero wheels is to possibly make you a second or so faster in a crucial race where that second might count. That's my take. Not to state the obvious but how you position your body matters far more.
 

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Look at it like this; aero wheels will not stop you from getting to class A and in some specific instances may give you a temporary small boost but they will not sustain you there if your legs do not come along.
 

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There's no doubt that a 10w difference could be significant in those conditions or any others, for sure. However, there are a couple of things that call actual dynamics of the situation into question for me.

Before I start let me just say that I have an absolutely enormous case of "being that jerk on the internet" fatigue, and so it's not without a huge bit of hesitation that I go into this. Also, this is my analysis, given my experience and knowledge. It's not "nananana I'm right and you're wrong so go and stick it where the sun don't shine."

First off, you don't say which wheels you have but in any case you'd need to ensure that the wheel and tire combo (and interaction with frame/fork) you're using is indeed capable of providing that benefit.

Second, as you said, you are drafting. It's been conclusively demonstrated, and should be intuitively obvious, that drafting reduces aerodynamic benefits of any equipment. From memory, Specialized pegged it at 30% for the second wheel rider and has it go up to a max of 40% from there. So 10w becomes 7w becomes 6w pretty quickly.

Third, the precision which you're able to ascribe to this situation is notable. I say this both as a competitive sailor with significant credentials and as a former salesman and technical consultant for a sailing instrumentation manufacturer. I've had articles published in top tier sailing magazines about wind instrumentation, and I would just find it notable to have that much precision in what must be a guesstimate. I've windsurfed in the delta, though don't remember precisely where. Somewhere near Rio Vista. I've also taught a week long sailing clinic at Tinsley Island so I know the general area and the wind. It's windy, and extremely gusty and shifty. Combined with the effect of a group of cyclists, it would be conservative to call the wind at wheel level "chaotic" in that situation. Air is lazy, it doesn't like finding its way into nooks and crannies. In sailing, we call that the "snow fence effect," where air will basically flow over and around a large obstacle (like a group of cyclists). This is why sailing coaches (and I've coached to world and national titles as recently as one year ago, which again I say not to brag at all but just to hopefully establish that I'm not just some opinionated d-bag) continually hound their athletes to get separated from large packs of boats. The best air flow is where the air faces the minimum of obstacles.

Every gust changes the apparent wind angle (a term I'll always find way better than yaw), as does every acceleration and deceleration, every little turn, every hill, every rock of the bike, etc.

Fourth, air doesn't just go from laminar flow to turbulence (stall) and back like turning a light switch on and off. It's not like "we're at 12.5* apparent wind angle now - 10w bonus to me." Once the air gets chopped up and turbulence occurs, the air doesn't naturally seek the quickest route to reestablishing laminar flow. As with so many things in life, it's way easier to lose the flow than it is to get it back. I wrote a blog post touching on this about 5 years ago which which is still relevant.

Fifth, you're assuming that the deeper wheels are a "pure gain" environment. No losses due to increased handling demands or anything else.

Sixth, read "Top Dog" by Po Bronson and Ashley Merryman. Totally fascinating book that explains how your mind was likely giving you way more than a 10w boost in that situation. That's a bit sideways to the whole discussion but it's a book that absolutely everyone would benefit from reading.

There are others beyond those but those are the big ones and I've got to get to work. Again, this isn't me being argumentative or denying that an extra 10w helps or that wheel aerodynamics don't matter. I'm certain that you thought your wheels were an advantage in that situation, which per my sixth point is probably all that you needed in order for that to fulfill itself. But while your analysis is really good, it's - pardon the pun - too finite for me.

Happy Friday.
 
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