kingfishr

Isn't the aero benefit only relevant at a maximal or near maximal effort? The fact that someone doing 14mph gets a greater time savings is only relevant if they are in a time trial, and their maximum effort is 14mph. But as soon as you are riding in a group your pace is set by the group and not your max effort. So no matter what kind of rider you are, if you want an additional edge when you are at maximal effort, than an aero frame might be one solution. But if you're not racing it's never going to provide much of a benefit...

Campag4life

Everybody has a thought on this and mine is, the ride quality deficit and fractional increase in weight, isn't worth the fractional tube shape difference translating to any speed on a road bike. On a TT bike, go narrow tube
So I want the best 'feeling' and climbing bike with explosive acceleration if racing...and yes aero wheels...but not an aero frame because the give up to me is too much for overall performance. The guy who won the TdF this year agrees btw.

sced

Since you're not really competing with anyone but yourself, what point is there in just buying a faster time as opposed to actually doing better because you were physically and mentally better prepared?

These arguments by ordinary people for buying equipment in order to save a few seconds or even, for God's sake, a whole minute on some personal best or inconsequential race are inherently vacuous.

wphamilton

When I see people proclaiming that the speed doesn't matter if you're not near a race podium, I always get the mental picture of fat tire beach cruisers, and yelling "pin a number on" at everyone who passes.

Why can't we stipulate that speed does matter to various people for various reasons, and look at the aerodynamics question from that basis?

wphamilton

The original question "is it really that big of a deal as long as the bike frame is fairly smooth and streamlined?"

Personally, no it's not that big of a deal. If it saved me 30 seconds on a beer run, well I do like having 30 seconds more time for something else. But the frankly minor aero gain isn't enough for me to seek out a frame optimized for that one quality.

StanSeven

An excellent suggestion.

gregf83 

You obviously don't compete and that's fine but it shouldn't be that hard to understand that for many people competition is enjoyable and part of the game is doing better relative to your peers.

canam73

I don't know if sced competes but I know I do and I understand his point. I often do endurance events each year on the same equipment I used the first time I entered them as a direct comparison to compete against myself. I also race crits on bike that is not my most aero, partly as a "race what you can replace thing" but also because my results are always going to be relative. I am an amateur and always will be, and the attraction for me is in the actual competition, not seeing a number afterwards.

If I was either truly near the top of the field (meaning pro or at least sponsored in some way), or right at the bottom where I needed a boost to just to make a time cut or stay with the pack, I might feel differently. But as long as I am relatively competitive, which I am, the small equipment gains and losses just don't seem that important.

gregf83 

I'm the same way as far as aero bikes. I don't have one and have no plans to buy one. In the crits I do there are maybe 20 factors that determine my results and the aero effects of my bike is well down the list. On the other hand I do understand why someone would be interested in optimizing their equipment either for weight or for aero. I have a couple of power meters and collect way more data than I 'need' but I enjoy it and it is a hobby after all.

I don't think you need to be at the top of your field for it to be relevant. For example, if you're competitive in Cat 3 racing against the same guys every year you might want to do everything you can to improve your results even if it's only for bragging rights.

Darth Steele

Nothing makes me smile more or brightens my day like seeing some fat guy on the latest and greatest aero/tri bike.

oh man, I love it. And if by chance he breaks 15mph and reaches close to 16mph on the flats then that is money well spent. These gentlemen will always spend countless time expounding the virtues of said bike at the rest stops, it doesn't matter that they were the last to arrive at the stops.

Team Sarcasm

if someone is better then you, someone is better then you. And bikes being relatively equal, an aero frame vs. a normal frame wont change much.


but with enough money thrown into something...........

Smokehouse

I'll dodge the entire question for the most part but I'd like to say that same thing I always say about quality of bike/kit. It sounds dumb but I always tell myself:

"Feel pro, ride pro"

When I finally stepped up to a nice road bike, and put on full cycling kit...I "feel" pro. I have no delusions of grandeur, I am not pro by a country mile. BUT...when I "feel" pro, I ride hard. It's in my head, I know, but it's amazing what you can do when your head is in the game.

So...for many, if they buy a fancy aero bike, many will feel like a fancy aero rider. If they feel like one, they may be more prone to acting like one (obviously, within the limits of their abilities).

delcrossv

2 cents:

Here's the drag equation without Crr (rolling resisitence))



Cd is the drag coefficient which is a form factor- that's what Aero frames try to reduce. The also reduce A, but a little compared to the rider

A is the frontal area of the machine/rider combination.

Let's look at various "A's"



Rider positioning counts for alot more than frame configuration. But if everyone is in position 4 (like doing a TT) then that small improvement in CdA makes a noticable difference.

and finally here's a nifty table of CdA's



Credits: Freely stolen from Lonnie Morse.

grolby

Fair enough, the parameter being discussed - speed or time - makes a difference. That said, while you may be right that most people may TALK about "going faster," they are still ultimately interested in finishing faster. Forgive me, as this will sound a bit ridiculous, but you don't set a PR by going faster, you set a PR by finishing in less time. In real terms, that means a higher average speed, of course. But to dig into it a bit, someone who wants to set a PR on a favorite training route, or improve in a time trial or triathlon doesn't need to be able to increase their maximum speed. Okay, maybe an aero benefit will make it possible for me to go 37 mph when I'm going all-out versus 34 or 35 mph. As a road racer, that matters to me because being able to follow attacks and sprint competitively is more important than being able to motor along at a high average speed. For a time trialist, triathlete or just a club rider trying to ride a faster century, being to reach a higher max speed is irrelevant as they will just be wasting energy.

And I'm afraid I have to disagree that a slow rider will not care about saving 14 minutes. Slow riders also get personal goals and have aspirations! What is with the continual assertion in these threads that only fast people want to lower their times either in competitive events or for personal satisfaction? What matters is what you care about. If said slower rider doesn't care about improving their times, then obviously they shouldn't worry about getting an aero frame. But slow people who want to improve their times do exist, and they will see larger improvements with aero equipment than the people who are already fast. That's the whole point.

I'm not sure what you mean by that. Not significant in the outcome of a competitive event, true. But that's often not what people are shooting for. To use running as an example, the number of people who sign up for a 10k expecting to be competitive with the elite athletes at the event is quite small. But it's common for people who sign up to have a goal or aspiration for the event, and it often involves going for a personal best. People do the same thing with organized rides or triathlons that they enter, or even just on their personal training loop. For them, the benefit could be very significant.

Right, that's what I'm saying - you seem to think that the fact that lab data cannot tell the whole story means we should just throw our hands up in the air and pretend that the data is useless. But that's baloney. Do you think drugs get to clinical studies straight from the idea phase? No! Things get tested in a lab first to prove that the principle of operation is sound. That lab data is extremely valuable. This analogy has limitations, of course - aerodynamic equipment development and testing is much simpler and much less difficult than drug development. And as time has gone by, lab testing for aerodynamic equipment has gotten sophisticated enough that most aero equipment being developed today truly is better-suited for real world conditions than it used to be. Field testing is great, but the fast-in-the-real-world equipment is being developed in wind tunnels. Geez, I guess I'm sorry that this upsets your world view, but lab testing of aero gear is by far the best way to develop equipment that is fast under real world conditions because it is actually possible to examine different components of the environment separately (yaw angle vs. wind speed vs turbulence, etc) and tweak the design to optimize for each. This is MUCH more powerful than trying to develop with field testing.

Obviously, lab data needs to be taken in the proper context; if you see a test showing that HED Trispokes are faster than Zipp Firecrest wheels, you should make sure you know what component of performance is being measured. In that case, you can bet that comparison was made at very low yaw angles. Another test might show the Zipps as faster - in that case, the test was probably done at higher yaw angles, where the Zipp wheels are going to clobber a Trispoke. This information can actually be very useful, as now you can make a decision about which wheels to use in different circumstances - Trispokes will probably be faster on an indoor velodrome, or in very calm conditions. For all your shouting about how we need to have field testing, field tests will not reliably give you that kind of granular data!

Really, you aren't favoring field tests because they are more scientific at all. You are using science and "common sense" as a shield for your own biases. Yes, independent studies and field testing are great and more would be nice. That doesn't make the wind tunnel data unreliable, false or useless.

grolby

+1000. Personally, I find the suggestion that no one who is not in the hunt for a race podium "should" care about speed distasteful, even insulting. Isn't it up to an individual to decide what matters to them, whether or not they should set goals for improvement and how they go about achieving that improvement?

I will absolutely be the first person to say that the benefits of frame aerodynamics are small, that the bang-for-buck you get with an aero frame is even smaller and that there is no need to be anxious about whether your bike is fast enough when there is still lots of low-hanging fruit to go after first. I'm a bike racer myself, with a skinny-tube steel bike and 30mm alloy wheels, it's not like I'm going out to equip myself with the latest and greatest aero gear. I have other priorities and a tight budget besides. But, to the question of whether frame aerodynamics make a difference (and whether that difference can be measured reliably in a wind tunnel), the answer is an unequivocal YES. Is it really so hard to hold more than one thought on a subject in your head at once?

njkayaker

???

People commonly talk about "going faster".

They also commonly talk about a benefit as a percentage change of some base performance.

Somebody going at 11.1 mph would gain 0.5 mph on a tri bike and shave 14 minutes (4.3%) off of a 60 mile ride.
Somebody going at 27.0 mph would gain 1.6 mph on a tri bike and shave 7.5 minutes (5.6%) off of a 60 mile ride.

The person going 27 mph decreases their time by a larger percentage.

If you want to talk about absolute time saved, go ahead. But be clear that's what you are talking about (rather than saying people are "wrong" without explaining why).

Keep in mind that the aero benefit drops to zero at some "high" speed.

Keep in mind, too, that the numbers I'm showing are estimates and are comparing "in the drops on a racing bike" versus a "triathlon bike". I'm not sure if the model is assuming any aero benefit to the frame. Most if the increase in performance is likely going to be due to the rider position on the tri bike, which, I suspect, is going to be significantly larger than the effect of the difference in the frame.

https://cyclingtips.com.au/2010/04/bi...ial-equipment/

Using equipment to make significant changes in a PR is a little suspect anyway since it doesn't demonstrate an improvement in your ability.

5.7%? It would seem very unlikely that it would have such a great effect at that speed!

I wasn't talking about "maximum speed". I don't think anybody was.

According to this (it might be old), an aero frame is the most expensive way to increase your speed:

https://cyclingtips.com.au/2010/04/bi...ial-equipment/

You haven't established that this is correct at all.

Saving 14 minutes over 5.4 hours on a 60 mile ride isn't necessarly "important" (a value judgement) at all.

Even a smaller benefit in the racer's case would likely be much more valuable.

Campag4life

Agree with this.

canam73

Personally, I post in these threads hoping people will simply get a more realistic view of what gains aero drag and weight reductions might garner. If somebody fully understands what returns they are likely to see on their investment and want to buy a new frame or wheels anyway I am happy for them.

But it is not uncommon for somebody to start a thread who has just bought a new bike or some other expensive upgrade and is wondering why they don't notice much if any difference. Many of those people appear to have been caught up in forum and/or marketing hype. And in case one them happens to read this thread or one like it before "pulling the trigger", I think it might be beneficial for them to see some realistic info on what is actually on offer and see some opinion on how it might play in to there specific wants and needs. They might even see that there may be an easier or cheaper way to accomplish their goal through training or a fit adjustment that will have a bigger impact.

And for every thread I see like that, I am guessing their are countless other lurkers living in denial.

grolby

Holy cow, this is awfully vociferous for such a small point. I was of course referring to absolute time saved at slower speeds, which I do not need to establish at all - it's simply a fact that aero benefits will accrue a larger absolute improvement in time over a course to a slower rider. But more than that, I was pointing out that there's not some magic speed at which aerodynamic benefits are suddenly important. Nor can the "importance" of the benefits be validated by a particular event that the rider is entered in. The only objective way to answer the question of whether aerodynamics matters is by showing that better aerodynamics do improve speed or lower times over a fixed course. Anything else comes down to the humans involved and their various values and motivations. I can't and won't tell anyone how much they should care. I can tell you that I have much higher priorities, as a bike racer, than getting my hands on the most aerodynamic equipment available. That doesn't mean an aero frame would not benefit me.

As for your attempts to educate me about the importance of body position and the poor bang-for-buck of an aero frame - thanks, but those facts are a) known to me, and b) not relevant.

grolby

Oh, absolutely. I get frustrated because it seems that, every single time this comes up, we get a whole posse of people trying to establish conditions for when aerodynamics or weight are important or when they are not that have nothing to do with the empirical reality of what an aero frame or lightweight wheels will actually do for you. So we get things like "unless you're racing," or "aero only matters if you're already really fast" and other irrelevancies that need to be debunked.

And it's too bad, because I am 100% on-board with showing people the low-hanging fruit of better performance that they can achieve for much less money than fancy aero wheels or aero bikes, or even for free. I am grateful for people like delcrossv showing up in these threads to point out the great significance of rider position. I have to admit that I too easily end up pulling my hair out and getting annoyed at the nonsense when it would be more productive to give out that kind of information. Unfortunately, I came into this thread in a grouchy mood yesterday, which should have been a clue for me to not get involved.

StanSeven

Not jealous are you?

Darth Steele

not at all,

I don't get the correlation between mocking someone and jealous. Please explain it to me


I also mock people for wearing crocks with socks... yes, that means I am jealous of them

StanSeven

Most people don't care what other people ride. Or they people that have nice bikes. Saying you get a smile out of fat guys on the latest and greatest sounds like jealousy to me. Otherwise why even care?

Darth Steele

lol, so you don't mock anything unless you have vested interests?

you got me, I am jealous of fat guys on tri-bikes..guilty

sced

This is great. The fact that you can simply go with a fairing and cut the drag by an order of magnitude really underscores what a Rube Goldberg affair all the other aero stuff like booties, expensive frames and wheels, funny helmets etc. is. If you want to go really fast, just add a fairing to that old tank everybody laughs at.