Illusion of "aero" bike frames
10-05-19, 07:09 AM
#76
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Exactly.
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10-05-19, 02:46 PM
#77
Aluminium Crusader :-)
I'd be very surprised if Lemond's "aero" Bottecchia frame reduced much drag at all, despite the tiny "fin" behind the head tube, and what I gather were ovalised main tubes.
For instance, recent tests have obviously shown that a horizontal top tube is more aero. I suspect he would've been better off on a standard frame (perhaps smaller than his usual size, to enable the low bars) with a long, aero seatpost
For instance, recent tests have obviously shown that a horizontal top tube is more aero. I suspect he would've been better off on a standard frame (perhaps smaller than his usual size, to enable the low bars) with a long, aero seatpost
10-06-19, 03:56 AM
#79
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10-06-19, 05:15 AM
#80
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I'd be very surprised if Lemond's "aero" Bottecchia frame reduced much drag at all, despite the tiny "fin" behind the head tube, and what I gather were ovalised main tubes.
For instance, recent tests have obviously shown that a horizontal top tube is more aero. I suspect he would've been better off on a standard frame (perhaps smaller than his usual size, to enable the low bars) with a long, aero seatpost
For instance, recent tests have obviously shown that a horizontal top tube is more aero. I suspect he would've been better off on a standard frame (perhaps smaller than his usual size, to enable the low bars) with a long, aero seatpost
10-06-19, 01:03 PM
#81
Aluminium Crusader :-)
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10-06-19, 02:31 PM
#83
Rhapsodic Laviathan
10-06-19, 04:08 PM
#84
Rhapsodic Laviathan
I have a military bag from my stepdad; I would use it to carry a load of laundry and I swear I was faster. I figured it made my body more aero, as there was more surface area along my side profile and a more rounded trailing edge versus my turbulent flat back. Almost like the magnus effect, especially since I wasn't going 20+mph. I still felt the difference, I wasn't pushing as hard to get speed.
10-06-19, 04:22 PM
#85
Rhapsodic Laviathan
10-06-19, 04:46 PM
#86
Rhapsodic Laviathan
I knew somebody that had one of these tanks at the co-op. We were comparing the frame simularities to it and my Genesis Roadtech, as both are technically aero frames. Yes my roadtech was lighter, even than his 1990 World Sport.
10-06-19, 11:33 PM
#87
Aluminium Crusader :-)
Ha, nah, on here.
Good point. 
Even if it he wasn't busy chewing, he might've been too busy unwrapping all the stuff he had in his pockets
Even if it he wasn't busy chewing, he might've been too busy unwrapping all the stuff he had in his pockets
10-06-19, 11:38 PM
#88
Aluminium Crusader :-)
10-07-19, 12:35 AM
#89
Senior Member
Because it's the same design that levers for flat bars use.
Also because it allows for housing routing with minimal sharp bends, which helps to minimize cable friction. Almost nobody bothered putting return springs in brake levers until "aero" cable routing added a bunch of stiction.
Also because you can fiddle with brake cables and housing without pulling up the bar tape. (Downtube shifters achieve the same result for shift cables and housing.)
Anyway, the main advantage of "aero" brake levers isn't the housing routing at all. It's the placement of the brake lever pivot: it gives the fingers a more squeeze-like pull angle when braking from the hoods.
Also because it allows for housing routing with minimal sharp bends, which helps to minimize cable friction. Almost nobody bothered putting return springs in brake levers until "aero" cable routing added a bunch of stiction.
Also because you can fiddle with brake cables and housing without pulling up the bar tape. (Downtube shifters achieve the same result for shift cables and housing.)
Anyway, the main advantage of "aero" brake levers isn't the housing routing at all. It's the placement of the brake lever pivot: it gives the fingers a more squeeze-like pull angle when braking from the hoods.
10-07-19, 05:02 AM
#91
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Purely a matter of curiosity while scanning this thread, is there any science to back this "aero" business, with wind tunnel tests, etc?
10-07-19, 06:55 AM
#92
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The reason for dimples on a golf ball is to disturb laminar flow where that combined with the spin of the ball creates lift. So we need a design where the TT spins creating a huge advantage on the climbs
dave
10-07-19, 07:07 AM
#93
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Univega's 1984 catalog shows a 20 lb "Aero" model as their top of the line bike. I have never seen one of these, they must be quite rare. Would love to modify one of these with modern wheels and components.
10-07-19, 07:13 AM
#94
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I realize that this was mostly in jest, but just because this is an internet discussion board ...
The reason for dimples on a golf ball is to disturb laminar flow where that combined with the spin of the ball creates lift. So we need a design where the TT spins creating a huge advantage on the climbs
dave
The reason for dimples on a golf ball is to disturb laminar flow where that combined with the spin of the ball creates lift. So we need a design where the TT spins creating a huge advantage on the climbs
dave
https://www.autoblog.com/2009/10/22/...-dimpling-mpg/
10-07-19, 07:43 AM
#95
Aluminium Crusader :-)
Last edited by 531Aussie; 10-07-19 at 10:07 AM.
10-07-19, 09:35 AM
#96
10-07-19, 12:41 PM
#97
Aluminium Crusader :-)
If it's good enough for a ship it's good enough for a bike. As for a catchy name......hmmm....
Perhaps if some of the normally non-moving parts of the bike spun like this, the minor lift generated could reduce rolling resistance. 
