Do Aero Road Bars look ok on Non Aero frames
Moderator: robbosmans
53x12 ... the issue re on the hoods is that given the typical yaw angles when cycling the aero section of the tops will be sheltered to a significant extent by the hands on the hoods and arms attached to those hands.
That is why we need a disaggregation of any test that claims to have combined time on the drops with time on the hoods to measure bar drag ...
That is why we need a disaggregation of any test that claims to have combined time on the drops with time on the hoods to measure bar drag ...
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Stiff, Light, Aero - Pick Three!!
Stiff, Light, Aero - Pick Three!!
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The only place I could see it looking a little goofy is with a classic-looking small tube steel/ti bike. Modern bikes with their hydroformed and chunky tube geometries are sufficiently swoopy that an aero handlebar fits. Does certainly look better with deep rims, but even with some 30mm alloy hoops, it's not too out of place. Something like a 32 spoke open pro, well... (and even then, if you're out riding, I'm happy to see you out here).
Round tube frame + aero goodies = "Hey man, working with what I've got" and ain't nothing wrong with that. Unless he/she blows my doors off, but that ain't the goodies.
Round tube frame + aero goodies = "Hey man, working with what I've got" and ain't nothing wrong with that. Unless he/she blows my doors off, but that ain't the goodies.
I also think that a skinny steel frame with a slim head tube might be more aero than some half-assed aero frames with super fat tubes, especially since the angled down tube presents a nice oval section to the wind. Would love to see/do a test.
Krackor wrote:I doubt time spent in each position comes into play. They probably took a measurement on the hoods then took a measurement in the drops and averaged the two.
Which would imply an assumption of 50% of time spend in each position ...
It clearly is relevant when the only aero benefit is the tops.
53x12 ... re the head-on shot ... a photo can fail to capture wind direction. Typical yaw angles for amateurs will reduce any "head-on" aero benefits because of arms and hands,... though it's not clear how this has been measured in the tests that have been done ...
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Stiff, Light, Aero - Pick Three!!
Stiff, Light, Aero - Pick Three!!
- jekyll man
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Sawyer- its not just the position that can make them more aero; cabling is generally cleaner too (ie exiting out the rear and not looking like the proverbial birds nest), so whilst probably only a minimal gain on its own, it all adds up.
Official cafe stop tester
I don't think you'll ever get anything better than the tour test, unless someone does a Chung method road test.
Re Yaw angles, IMO this is a marketing buzzword invented by wheel manufacturers needing to push wide rims and tires to us. Actual encountered yaw angles for people who actually care about aero are much lower than generally discussed.
If all you ride is the coastal highway maybe, but for all the rest of us, the wind will mostly come from the front.
Reference:
http://www.cyclingpowerlab.com/Yaw.aspx
"In fact modelling suggests that somewhere between 50 and 70 percent (let's say 2/3rds) of effective wind yaw angles experienced by a rider are lower than 10 degrees, the faster your ride, the higher this percentage."
Re Yaw angles, IMO this is a marketing buzzword invented by wheel manufacturers needing to push wide rims and tires to us. Actual encountered yaw angles for people who actually care about aero are much lower than generally discussed.
If all you ride is the coastal highway maybe, but for all the rest of us, the wind will mostly come from the front.
Reference:
http://www.cyclingpowerlab.com/Yaw.aspx
"In fact modelling suggests that somewhere between 50 and 70 percent (let's say 2/3rds) of effective wind yaw angles experienced by a rider are lower than 10 degrees, the faster your ride, the higher this percentage."
Marin wrote:Re Yaw angles, IMO this is a marketing buzzword invented by wheel manufacturers needing to push wide rims and tires to us.
+1
There's a certain truth into that.
sawyer wrote:
53x12 ... re the head-on shot ... a photo can fail to capture wind direction. Typical yaw angles for amateurs will reduce any "head-on" aero benefits because of arms and hands,... though it's not clear how this has been measured in the tests that have been done ...
Not really. Go to a yaw calculator and play with it. Typical rider sees low yaws most of the time. At least where I live. Remember wind speed (at least here in USA) is from a weather station pole 3m off the ground. True wind speed is much less than reported. I am usually riding in wind angles <7 degrees here. So for most riders, head on/law yaw is still the vast majority of the time.
This also fits in with data that several bike companies have reported from their extensive testing.
"Marginal gains are the only gains when all that's left to gain is in the margins."
Marin wrote:I also think that a skinny steel frame with a slim head tube might be more aero than some half-assed aero frames with super fat tubes, especially since the angled down tube presents a nice oval section to the wind. Would love to see/do a test.
Isn't that the case with everything in life? Some product half-assed in design and/or production is half-assed? When talking about aero road bikes, we shouldn't be talking about the worse frames but the best. If one is considering an aero frame, then one should really consider an aero frame. It would be like wanting a ww frame but then considering a frame that weighs 1300 grams.
Small diameter tubing is definitely faster than wide diameter tubing. But the shape eventually is the limiting factor.
"Marginal gains are the only gains when all that's left to gain is in the margins."
There's no graphic for an ellipse...
There is a graphic for ellipse online after a little search. But I thought we were talking about small diameter steel tube frames?
It is a fallacy to think that aerodynamics is just about diameter or size of something punching through the air. It is much more complicated than that and deals with how the air interacts with said object and flow seperation and boundary layer separation. Some items (like Cervelo) are designed with a rider onboard as they design the flow around said rider as best they can.
It is a fallacy to think that aerodynamics is just about diameter or size of something punching through the air. It is much more complicated than that and deals with how the air interacts with said object and flow seperation and boundary layer separation. Some items (like Cervelo) are designed with a rider onboard as they design the flow around said rider as best they can.
"Marginal gains are the only gains when all that's left to gain is in the margins."
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Due to the angle, the downtube presents an elliptic cross section to the wind, so this is very relevant to thin tubed steel frames