chaadster

Their net drag reduction value does take into account 0° yaw, but not exclusively. From one of their many and very detailed blog posts:

“We have updated our 2012 NDRV formula. In 2012 we thought a rider spent 80 percent of their time between 10 and 20 degrees of yaw. Now we know that a rider actually spends 80 percent of their time between zero and 10 degrees of yaw. This discovery forced us to focus on designing wheels that were more aerodynamic at shallower yaw angles instead of focusing on designing wheels that were fast between 10 and 20 degrees of yaw. Our old estimates for how much time a 2012 FLO wheel would save you aren’t as accurate as they could have been, and we have recalculated them below. We have compared those to the new 2016 models.”

https://blog.flocycling.com/aero-whe...unnel-results/

Lombard

As Warren Buffett would say, beware of geeks bearing formulas.

bblair

I don't understand this. Unless you always ride the same direction. The wind is always the same direction and strength. You only ride an out-and-back route. Maybe some of you have wheels for every occasion: climbing wheels, windy wheels, wet weather wheels.....

Lombard

I ride mostly loop routes. Winds vary, but across open farmland, can come in any direction and are unpredictable.

I get enough crosswind action as it is and all my wheels are 27mm or less. Being that I have wide shoulders and also ride more upright, aero wheels would be zero advantage for me even without crosswinds.

terrymorse 

At a given speed, aero wheels save the same number of watts for all riders. The speed advantage never goes to zero.

Lombard

That's at a given speed. If you are a 20mph hammerhead, then possibly. Otherwise I would be unlikely to notice a difference.

bblair

Ok, back to the OP question: should he buy new wheels. My honest answers are that my current alloy (American Classic) are fine, but are showing wear on the brake tracks. Quality, mid level wheels for rim brakes are getting harder to find, so I decided to buy while there is still some choice. Many high end hubs/wheels no longer come in rim brake versions. So, kind of like buying a new car, while your old one is ok, but has 200k miles on it.

And they look cool.

hubcyclist

I did a couple of rides with my new 36mm carbon wheels. Both rides ended up with a speed of 18.8mph and averaging around 220w (normalized power 241 and 231). I’ve done solo centuries on my stock allow rims at 20mph with similar power. Obviously only a couple of data points but consistent with my previous experience trying out a friend’s 60/88mm wheels and not seeing a big change in my speed for similar effort.

Hermes

I think it is tricky to accurately measure gains or losses due to changing equipment from riding routes but I take the point that using your protocol, you are not seeing any difference. I think a more accurate way is to go to the velodrome (indoor or outdoor) and ride laps and collect data. One needs use a speed sensor and do a roll out to set the distance covered by one wheel revolution and an accurate power meter.

GhostRider62

I can't understand why riders do not understand that any aerodynamic improvement results in more time savings for slower riders compared to so-called hammerheads. They may not care or may not notice but the effect is real. I believe the effect is greater for slower riders due to more transitions (so-called stalling or moments of detached airflow) and the lack of symmetry (takes longer to get attached, all nice and tidy compared to losing it and slow riders being a higher yaw in general are always closer to that effect)

I have RChung'd the crap out of different setups and half the time I trust the data and the other half I don't trust it but if you do enough runs and also do real world ABBA testing, the lies are half exposed.

hubcyclist

sure, definitely more scientific ways, but as with a lot of my riding I look at general trends in my day to day usage, so its still really early for me to really draw conclusions, just something I’ll keep observing over time, esp on my z2 rides where I tend to stay really steady

The Chemist

I got my first set of deep (50mm) carbon wheels for my new Ti road bike. They feel faster than the alloy rims I had on my old bike, and the new bike as a whole is definitely faster than the old one, but I have no idea how much of that is due to the wheels.

Still, as far as I'm concerned, they look cool and they sound cool, and I don't have a major problem with crosswinds with them, so I can't complain.

vespasianus

I believe the impact starts at 20 KPH.

chaadster

Well, no. Rim shape doesn’t change with speed, so Cd doesn’t change, so lower Cd is lower Cd at every speed.

But regardless of whether the effect occurs at 1mph or 10mph, whether someone notices it is an entirely different question with a whole host of variables, most of which have nothing to do with whether the effect exists. I mean, there are more than 5 thousand satellites in orbit providing myriad services, but few folks ever notice one because we simply don’t look for them.

rosefarts

Who is the customer? Let’s get silly.

Aero wheels help. Look at the breakdown of what allows someone to ride faster though. Body shape and body position are key factors, the wheels are to gain a little more.

Rider A has a dedicated breakaway bike (lets not use Time Trials here). He’s planning to attack the pack early and is hoping that some disorganization helps him get to the finish line first. And extra 0.1mph could mean everything. Damn right he’s using aero wheels.

Rider B has a pretty cool mid tier carbon road bike. He also has some grey hair, a little gut, and a cardiologist. He’s got a weekly loop he rides alone. He’s well aware that aero may allow him to do the loop 0.3mph faster, but he also knows his position is totally upright, his fitness level moderate, and one of the kids is going to need braces soon.

See the difference?

Koyote

First, I'm pretty sure a cardiologist can afford fancy wheels and braces for his kid.

Second, I do get your point. I find it pretty funny every time a poster asks whether this or that little bit of equipment will make him a little bit faster, and there is no mention of racing or even challenging group rides. There's a word for such riders, and it rhymes with 'hoser.'

FWIW, as far as equipment goes, I find the most noticeable difference comes from my jersey choice: going from a comfy merino wool club fit jersey to a proper aero (but still comfy, if it's a good one) jersey actually IS noticeable, at least to me. But I guess a great jersey isn't as exciting (to most riders) as a bling wheelset.

bbbean 

This! This times 100. I pull my hair out every time someone posts "this only has an effect above X mph" or "That only matters if you're in the Tour" as if we were talking quantum physics instead of relatively simple aerodynamics and efficiencies.
FWIW, lots of mere mortals ride for pure enjoyment and still want to ride fast.

bbbean 

No. If rider B is enough of an adult to see the doctor and have kids, he's enough of an adult to decide whether saving a few watts is worth a few bucks. He can also decide whether his car needs AC and satellite radio, whether buying name brand shoes is better than going to Payless, and whether it's worth paying an extra few bucks for faster broadband even though he never watches movies or plays online games. Crux of the matter is the wheels provide a benefit, and as long as the user appreciates the benefit and can justify the expense, it doesn't matter whether anyone else thinks it was worthwhile.

terrymorse 

Nonsense, that's gatekeeping. The desire to go faster on a bike is very common, and it isn't limited to competitive cyclists only.

rosefarts

I should have been more specific, I meant has a cardiologist, IE, isn’t in fantastic shape.

Although the point remains mostly the same if we say it’s an overworked doctor. Just replace the mid level carbon bike with a Serrotta.

Koyote

Guess I struck a nerve.

superdex

This. This. This. This. Everything else is keyboard jerking.

terrymorse 

No nerves struck. You just wrote some judgmental gibberish, and you got called out for it.

Eric F 

Nonsense. The enjoyment of moving down the road quickly and efficiently, under one's own power, does not require competition against other riders. Fast is fun.

rosefarts

Lets jerk some more.

Ive found that super light wheels “feel” so much faster than heavier wheels. Even when the clock doesn’t justify the feeling.

So if we’re talking about a theoretical cyclist who has an unlimited budget but does not have a person to finish ahead of. What is going to make this dude happier. Ultra light or aero?