What's the deal with aero road handlebars? Advantageous?

[carpediemracing]

Originally Posted by quauhnahuac

in tri it's generally conceded that the front section of the bike is the biggest determinate in aerodynamics. a cervelo p3 with a cockpit upgrade is 99% as fast as the much more expensive p6 that comes with the better aero bars standard.

given this, I assume aero road bars are useful to some degree. i've tried the s-works aero fly bars long term and really don't mind the flat tops, though I marginally prefer round tops from a comfort perspective. I would go with aero bars if it meant I would be more aerodynamic.

outfitting a new bike. any data on whether aero road bars are worth any speed?

There are two ways of looking at it:
- aero is always aero. If you have to buy bars and you buy aero bars, you have aero bars. If you buy the Griepel "biggest cylinder possible" bars then you'll always have these massive tops hitting the wind. Even if the benefit is minor, 0.1 or 0.2 mph, it's still there, every single time you go 25 mph (or whatever).

- the other is that will you notice it? You may not.

I went through a similar debate when I first got into aero wheels. I asked people about their wheels, I tried to get some data (not much out there other than on the Specialized TriSpoke at the time), etc.

Finally I had a conversation along these lines with one of my friends: Do you want the wheels? Yes. Can you afford them? Yes. Well then get them. It doesn't matter if they're faster or not, as long as they're not just bad wheels.

[echappist]

savings from aero road bars are greater than savings from an aero front wheel. So push comes to shove, get the bar first, before the wheel.

As for Garmins, I use an out-in-front mount that directly slots into the face plate of my 3t Arx stem.

As for aeroness, 26.7 mph at 335W on some rather bumpy roads (this from going around the course thrice). Of course my position is pretty aero, but i take whatever aero advantage i can get my hands on (bad number placement notwithstanding)



I should also add that the flat section makes doing the IAB a lot more comfortable

[berserk87]

Originally Posted by echappist

savings from aero road bars are greater than savings from an aero front wheel. So push comes to shove, get the bar first, before the wheel.

Where are you coming up with that?

[peanutgallery]

All the savings and then some is negated by those belgian touring socks

Originally Posted by echappist

savings from aero road bars are greater than savings from an aero front wheel. So push comes to shove, get the bar first, before the wheel.

As for Garmins, I use an out-in-front mount that directly slots into the face plate of my 3t Arx stem.

As for aeroness, 26.7 mph at 335W on some rather bumpy roads (this from going around the course thrice). Of course my position is pretty aero, but i take whatever aero advantage i can get my hands on (bad number placement notwithstanding)



I should also add that the flat section makes doing the IAB a lot more comfortable

[echappist]

CdA savings of bars vs wheels

Wheel data from here: http://flocycling.blogspot.com/2016/...reduction.html

The wheel i'm comparing against is not the 32H Open Pro, but rather a standard 30mm tall, 24mm wide rim (e.g. the Kinlin C31W). A 60mm front aero wheel will save you about 50 grams of drag (or 7.3 W) at 30 mph. At 25 mph, this becomes 4W.

Aforementioned aero road bars generally save 4-5W at 25 mph.

Which is to say, neither saves as much as what an aero road helmet would provide. Too bad i was idiotic and went wheel first, followed by the bar and finally the helmet this year.

Also, this: http://www.drag2zero.co.uk/wp-conten...-Sept-2012.pdf. Caveat being that a good helmet generally saves you quite a bit more; ditto a good skin suit. I doubt an aero road bar could reduce CdA by 0.025 (which is huge)

[shovelhd]

You're losing another 4w with that number pinning job.

[peanutgallery]

If I trim my ear hair, how many wattz?

I going to call BS on the aero road bars saving much if any at all. Wheels and the dorky lid I can see working out and making the biggest difference. Pretty sure the rest is all fluff

For the record, the cycling gods should remove the powermeters from the bicycles of all evergreen bike ride participants and eviscerate them in a giant pool of hot lava. It wrecks the ambience of the sport an ecourages all the worst attributes of the aging roadie as they ride/train like the grim reaper is chasing them. I can see a class action lawsuit for the spouses and families of those affected. Be bigger than dieselgate. Those aging roadies that persist should be sentenced to having Frank Day robot live in your basement while he continuously attempts to sell you power cranks

[echappist]

Originally Posted by peanutgallery

If I trim my ear hair, how many wattz?

I going to call BS on the aero road bars saving much if any at all. Wheels and the dorky lid I can see working out and making the biggest difference. Pretty sure the rest is all fluff

For the record, the cycling gods should remove the powermeters from the bicycles of all evergreen bike ride participants and eviscerate them in a giant pool of hot lava. It wrecks the ambience of the sport an ecourages all the worst attributes of the aging roadie as they ride/train like the grim reaper is chasing them. I can see a class action lawsuit for the spouses and families of those affected. Be bigger than dieselgate. Those aging roadies that persist should be sentenced to having Frank Day robot live in your basement while he continuously attempts to sell you power cranks

you are entitled to your opinions, but not your facts.

The fact is, the saving between aero front wheel over any modern alloy clincher is comparable to that of aero road bar over traditional roaad bar. If you dig a bit deeper, this (4-5W) is the difference between the 2nd gen of aero road frames over that of the first gen aero road frames.

Perception might say to you that the aero road wheels save a lot; perhaps compared to that 32H Open Pro, but not so much when compared to the current generation

[peanutgallery]

I think you've been shopping in Floyds new store. Your socks have more drag than the "aero" supposedly hooks you up with and there is no way the bars are as aero as a aero wheel.

Originally Posted by echappist

you are entitled to your opinions, but not your facts.

The fact is, the saving between aero front wheel over any modern alloy clincher is comparable to that of aero road bar over traditional roaad bar. If you dig a bit deeper, this (4-5W) is the difference between the 2nd gen of aero road frames over that of the first gen aero road frames.

Perception might say to you that the aero road wheels save a lot; perhaps compared to that 32H Open Pro, but not so much when compared to the current generation

[shovelhd]

Whatever gains your bars give you are negated by your hands draped over them.

[Mark McM]

Originally Posted by peanutgallery

I think you've been shopping in Floyds new store. Your socks have more drag than the "aero" supposedly hooks you up with and there is no way the bars are as aero as a aero wheel.

What do you call someone who chooses to ignore factual evidence (such as the data already presented here about the power savings of aero drop bars vs. front wheels)?

Maybe this will help:

Aerodynamic drag is largely determined by frontal area. If you look at a bike head on, you'll see that the handlebars are a very large percentage of the frontal area. In particular, a front wheel is roughly 66 cm x 2.5 cm = 165 cm^2, whearas the top section of the handlebar is roughly 42 cm x 2 cm = 84 cm. But here's the thing: The frontal area of an aerowheel is the same as a non-aerowheel. In contrast, the top section of the aerobar is only about half as wide as a non-aerobar, cutting the frontal area in half (frontal area reduced by 42 cm^2).

This means that a wheel can only improve aerodynamics by using a shape that decreases the drag coefficient. In contrast, the top section of a aerobar can both improve drag coefficient, and reduce frontal area. The net result is that although the aerobar is smaller than the front wheel, the combined coefficient and frontal area savings can reduce power as much or more than an aerowheel.

[benb]

Originally Posted by berserk87

I seriously question the testing behind that small, flat portion of handlebar versus a round section, in terms of gain, especially if your hands are resting there anyway at any point in the ride. Maybe knuckle shaving would offer more benefit?

Your hand should never be on the tops if you're going all out...

[berserk87]

Originally Posted by shovelhd

Whatever gains your bars give you are negated by your hands draped over them.

Yes - how are you saving anything that is being claimed (via the bars) when your arms are covering your bars?

The 2nd article references "aero bars" - this refers to TT aero bars, not aero road bars that the OP questioned. Are we talking about the same thing? I would agree that aero bars (ala TT bike style) would benefit more that a front wheel Just plain road handlebars with a wing-shaped top section I would debate.

I am not seeing anything in either article that supports your claim that aero road bars save more than an aero front wheel. Can you point out what I am missing?

By covering your bars with your arms, you have assumed the same position as TT aero bars, which indeed would offer you some efficiency.

[berserk87]

Originally Posted by benb

Your hand should never be on the tops if you're going all out...

Says who? What is "going all out"? A sprint? A 40k TT pace?

[thegunner]

Originally Posted by berserk87

By covering your bars with your arms, you have assumed the same position as TT aero bars, which indeed would offer you some efficiency.

I think Jim sometimes takes microefficiency gains too far, but the emphasis on reduction of surface area is across the width of the bar, not just the part where his hands are draped over the tops. a traditional bar is still going to have a circular cross section throughout the entirety of the width, if you reduce SA there, then you would be saving watts.

the amount i'm skeptical about, especially given the turbulence in that general area already, but i'm sure they're non-zero.