Chrome Molly

The comparison is interesting, but not sure how relevant it is. On a solo 40k for time you would probably take a tri bike. On a group/race 40k you would be on someone's wheel most of the way (I would anyway). Tough to measure responsiveness between a retro roadie and a venge, but to me that is where the important difference would be. Also if you are on a smooth bike then you may not be as worn at the sprint.

Still think the venge would be faster, but maybe due to the aero weight combination, with less aero and some weight factor.

noglider 

I suspect the differences are measurable at maximum effort by a very fit athlete but not if you're not super fit or you're not pushing yourself to the limit. If either of those is true, the difference is probably insignificant.

TimmyT 

It's not just cross sectional area but also vortex shedding. Cylindrical tubes are oval against the wind. The cross section is circular as a builder would cut the tube, but that is rotated relative to the direction of travel. Circles have really terrible vortex shedding. The way the tube sheds a vortex can decrease the resistance. Cross sections that allow smooth reattachment at the lee (or aft) of the airfoil (tube) decrease the resistance.

Here is a simulation of a cylindrical tube. Notice how there is a "street" of eddies behind the tube:

Better vortex shedding occurs on aerodynamic fins. These have smooth streamline reattachment.
This video shows how the streamlines break down with increasing attack angle. Notice how they start to look like the cylinder linked above.

A lot of work has been done on airplane airfoils. Less work has been done on bikes as there's less money in product design (and if you fall, it's not from the sky), though the same physics applies.

DMC707

How do you handle the downshift on this rascal with it on the underside of the shifter?

noglider 

I reach the thumb button by rotating my hand, pushing my thumb forward.. It may sound awkward, but I'm able to do it quickly and reliable without fumbling or looking, so it works great for me.

noglider 

Cool stuff, Dr. Tim!

Kevindale

Yes, this is why I'm a believer in aero drop bars, even though only a portion of the bar is in an airfoil shape. I imagine, as someone else noted, this is also very relevant to the shaping of forks. I think it must also be pretty relevant to the head tube, and only marginally on the downtube. Probably seatstays too, upper seattube somewhat, and of course rear wheel.

Of course you can go crazy with this, and apply it to the way all the parts fit together (bottle cages, tube junctions, etc), which is pretty much what some of these modern shaped frame-makers are doing. However, from looking at the published stats I've seen, the frame and standard frame components are a tiny portion of the drag, compared to small changes in rider position, tight/smooth rider clothing, shoe covers, shaving down, aero helmet, aero bars, aero wheels/tires.

At the end of the day, I think the frame gives by far the least bang for the buck on this score. Still, I'm curious to try a truly aero frame one of these days.

himespau 

Interesting. I'd have sort of thought that with all the turbulance due to pedaling, that the shaping of the seattube and rear wheel wouldn't matter as much as the front because the air is all choppy back their anyway (or maybe slicing through that mess would mean it matters more?).

Kevindale

I think the results from using full disks on the rear wheels shows how useful that can be. But you're probably right about the seat stays, though the more they can help shape that trailing air flow over the rear wheel, the better.

TimmyT 

Some time ago, there was a post on TdF average speeds from the inception of the race to recent results. A few things give incremental jumps (like index shifting) to the overall trend of faster speeds, but it is really hard to tell what the gains should be attributed to. Certainly, if you took a bike from 40 years ago (say Campag SR 12 speed with round tubes) and tried to race it against a modern bike (say 2x11 speed with aero tubes), it gives an overall slower time. That said, those teams are trying to save fractions of seconds in many cases, so if there were a better design, they would use it.

Jeff Wills

Well, the fastest bicycles don't depend on airplane airfoils. They've gone beyond that into shapes that allow for highly laminar flows. I went to watch the Human Powered Speed Challenge last September, and one of the fastest bike's runs was spoiled by a bug splat on the shell.

(Yeah, yeah... "they're not real bikes". So sue me.)

Documentary from 2015:
Gag video from 2016:
Cool sound track:

vintagerando

I finally got this together about a month ago. I have been riding and enjoying it as much as possible. I don't care how cold it gets, with this bike sitting in the garage, how can I say, "oh, moan, gripe, its too cold out to ride". I will keep riding until it becomes unsafe, (ie ice on the road.) Funny thing how the world works: as soon as I finished this build, what do you know, along comes another Waterford in just the right size. So, I think I may move all the new components to the "new" frame.

velofinds

What are some concrete examples of aero drop bars? (And are any available with a 26.0mm clamp diameter?)

T Stew

Are you talking about these https://www.google.com/search?q=aero...jrAq4Q_AUIBygC seem to be dozens upon dozens out there. Doubt you'll find any 26mm though, but if you're concern is to keep the quill stem there is atleast one classic shaped quill stem out there for the modern larger bar. I'd really like to try an aero bar just for the hand comfort on the flats on long rides, but I really think it would look pretty hideous on my old school bikes, but maybe on a retro roadie all converted to newer styled components might not be too bad.

Kevindale

Yes to all that. I'm using Bontranger Race Lite Aero drop bars on my Cannondale. Everything I've seen in aero drop bars is black anodized alloy or CG, all in modern stem diameters. It would be cool if someone offered a vintage looking silver alloy bar that worked with vintage quill stems, but I doubt it will happen.

Edit: I'll have to search through this thread to see if anyone has used an aero drop bar on a retro roadie. I know I haven't seen it yet, but would be curious.

Dfrost 

It would be an interesting aero drop bar that allowed the 26.0mm clamp of a quill stem to slip over the aero sections.

T Stew

Yeah, I have not seen any in silver. I did find a set of clip on aero bars in silver, but not drop bars. Maybe a DIY project of getting aluminum ones and removing the anodizing? Hmmm. Still be stuck with the 31.8 though.

bikebakman

The original paint was in very bad condition. So I made a bold decision...



For details, see Classic Vintage Concorde thread.

Barchettaman

Ooh, that Concorde came out beautifully.

Top work.

Jeff Wills

Like these?

Vintage Scott Drop-In Handlebars 42cm 26mm Greg Lemond TT Triathlon Bars | eBay

MRT2

My son's new old early 80s Gitane, with 105 brifters.

RiddleOfSteel

I got a bit tired of running classically dropped vintage drop bars for rain/commuting duty, as good as it looked, as fun as it was, and as cool as it was to run Sante 7s indexed DT shifters over a Sante FD and Superbe Tech RD. So over the weekend, in addition to tending to five other of my bikes in minor and major ways, my Ross received a mid-cold&soggy season disassembly and cleaning. Creaky and tired 5500 Octalink BB swapped for a much healthier 6500 unit, same 7700 DA cranks, some 1994-era 8-speed Record Ergo levers I got for super cheap (and threw new hoods on), VGC super shiny fun times Mirage RD and 7410 Dura Ace FD. Modern bar conversion (short/shallow Kona compact bars) and cheap "well used" (LBS advertisement of them) Campy 8s wheelset rounded out the changes and I have a very much upgraded commuter.

I really think there is something to replacing the quill stem with an adapter+1 1/8" stem+31.8mm clamp drop bar on an old steel frame. You can choose to do so or keep that classic sexy quill stem (I still do on a few bikes), but the "sureness" and not-jarring ridgidy that comes from such a conversion, especially when out of the saddle, is a great feeling. Regardless, it's a (even more) fun and now noticeably faster ride (I had jockey wheel drag on the Suberbe Tech RD), good thing for the sub-40° weather we have now.

Anyway, bla bla pretty bike safely indoors:

Lascauxcaveman 

I'm not feeling it in this case, but I guess a slammed, stubby stem like that has got to be pretty stiff, alright! Something I've never really considered, even though my stems are all rather swan-like 120s and 130s.

Thanks for giving me something new to worry about, next time I'm standing on the pedals trying to catch up the younger, leaner guys waxing me up the hill!

I do like the rest of the bike; reminds me a bit of my Nishiki Landau when I had it set up for winter commuting. You can't see it in this pic, but it has the same bespoke metalic silver panel on the head tube as your Ross. (No brifters, though):

Soody

Thin tubes look better.

easyupbug 

Agree, don't know why and don't care.