Are Aerodynamic in Wheels Important?

jane90

A question for all you experienced cyclists - in the real world, how much difference does having a set of aerodynamic wheels actually make? I'm not talking about the last few tenths when you're racing but just on a normal ride, does it make it easier to hold a slightly higher cruising speed for longer? How big does the depth have to be to feel the effect, if any? Many thanks.

ride_whenever

It's hard to say when the weights often vary wildly which makes a far larger difference to ride feel.

You certainly can notice the difference in depth say between a 40mm rim and a shallow one in terms of cruising ease, but they also tend to be stiffer.

ugo.santalucia

It is a very controversial topic... some will swear by aerodynamic rims, some will say it's all hype with little substance in the real world of 15-20 mph averages. I belong to the second lot, not because I don't believe in aerodynamics, but because the actual savings can be quanitified in a square of 7 x 7 cm, which is a very tiny tiny proportion of the total surface exposed to the air... the advantage is probably around 1%.
If that comes free of charge and drawbacks, by all means go for that, but if money is tight...

Stevie_gee

If you're cruising at high speeds (25 mph plus) then the difference is generally considered to be vast, but deeper rims are often heavy, and the rim is the single worst place on a bike to add weight, because of physics which I won't go into. This makes them much harder to accelerate, and at club riding speeds (afterall, this is road beginners) THAT is what you'll most likely notice, not the aero advantage

There is an article lurking on bikeradar somewhere which says that an aero helmet is actually a better buy that aero wheels! So if you're purely interested in a tt advantage then this will be cheaper and won't spoil normal riding. And won't be ruined the first time you hit a moderately large pothole

ugo.santalucia

There is a nice correlation between the weight of a car and the real world fuel consumption, the same correlation with aerodynamic coefficient is less obvious... Cars are faster obviously, so aerodynamics matter more, or so they should

Monty Dog

The are popular because you can have the words 'poseur' in 2-inch high letters on the side of your wheels when tooling-along - quite often this word appears in other forms such as "Zipp" "Mavic" "Easton" ;-)

clickrumble

Tried some for a while on one of my bikes, found them to be a problem in a side wind. As far as I'm concerned just another gimmick one can happily do without.

simon_masterson

Stevie_gee wrote:

If you're cruising at high speeds (25 mph plus) then the difference is generally considered to be vast, but deeper rims are often heavy, and the rim is the single worst place on a bike to add weight, because of physics which I won't go into. This makes them much harder to accelerate, and at club riding speeds (afterall, this is road beginners) THAT is what you'll most likely notice, not the aero advantage

There is an article lurking on bikeradar somewhere which says that an aero helmet is actually a better buy that aero wheels! So if you're purely interested in a tt advantage then this will be cheaper and won't spoil normal riding. And won't be ruined the first time you hit a moderately large pothole

This. Normally aerodynamics trump weight resoundingly, but unless you are going very fast, lighter wheels will probably make more of a difference to you.

(Though I have to say, I'm a little sceptical of the helmet vs. aero wheels proposition...)

markos1963

Aero wheels improved my 10TT time by 9 seconds, cost £500+
Aero helmet, skin suit and shoe covers improved my time by 44 seconds, cost £200

Work it out if it's worth it?

smidsy

Aero wheels = instant bling factor. 8)

Aero Helmet = instant 'look at alien head' factor. :-)

But to answer you OP its a definite probabilty that aero wheels may or may not offer advantages.

jane90

Thank you all for your replies and for confirming my suspicions. I've had a couple of comments recently that my wheels are letting my new bike down and I ought to upgrade to some aero ones which would be a noticeable improvement. But since I definitely don't cruise at 25mph and have no interest in racing, I was quite sceptical. I also think really deep rims look pretty ugly, so I'm very happy I can stick with what I've got without worrying that I'm missing out on buying an extra mile-an-hour! Thanks for your help.

Anonymous

WOAH there.
That isn't to say that it isn't time for new wheels!

There is always time for some new wheels. Just not aero ones.

tlw1

coriordan wrote:

WOAH there.
That isn't to say that it isn't time for new wheels!

There is always time for some new wheels. Just not aero ones.

good save

danlikesbikes

jane90 wrote:

Thank you all for your replies and for confirming my suspicions. I've had a couple of comments recently that my wheels are letting my new bike down and I ought to upgrade to some aero ones which would be a noticeable improvement. But since I definitely don't cruise at 25mph and have no interest in racing, I was quite sceptical. I also think really deep rims look pretty ugly, so I'm very happy I can stick with what I've got without worrying that I'm missing out on buying an extra mile-an-hour! Thanks for your help.

If it was another cyclist giving you the advice I'd be a bit sceptical too

New wheels will make a difference to your bike as will changing the tyres to something more suited to the type of riding you do compared with the amount of money you want to spend. As in life there have to be compromises sometimes with aero wheels being no exception as the downside to them is the "sail" like effect you can get from cross winds pushing you and the deep the rim section the more pronounced this can be.

Not going to big anyone up tonight but if your not looking at aero wheels as the answer but new wheels & you want them to be flash (or not if you don't want and prefer subtle), fit for purpose and not stupidly over priced then you could look at the hand built route.

Now if only we had someone on BR that did these...... OK only kidding Ugo is your man to talk too as I see it. There you go not bigging anyone up, just have seen some other BR contributors wheels made by Ugo and they do look very good indeed.

slowbike

I can only offer my limited experience with upgrading wheels ...

I rode a stock Allez with Mavic CXP22 rims on unbranded hubs - was fine and I could cruise everywhere at 15mph ...
It got to the end of last summer and I noticed a problem with the freehub so I decided to upgrade the wheels - I ended up with some Fulcrum racing 7 rims with FR5 hubs & aero spokes (those are the flat ones) - not an expensive wheelset by any stretch, but enough for my riding!
Anyway - what I noticed was that most of my riding didn't change - the climbs were still climbs and the flats stilled ran along nicely ... where I noticed the difference was when I got >20mph (after a descent!) and normally had to put in quite a bit of power to keep it going - it just felt easier. Difficult to quantify as there are so many factors involved, but I did get a PR on one segment straight after putting the new wheels on - probably partly helped by the tailwind and excellent timing of large overtaking vehicles....

jane90

Thanks guys, but just to clarify, I'm not really looking to upgrade my wheels. I've just bought my new bike and I'm very happy with it, I was just confused by some of the comments people have said about the aerodynamic wheels. I've seen a few threads debating whether aero frames really do have benefits at beginner level or whether it's mostly PR and it seemed to me to apply even more so to wheels, especially as I don't have an aero frame.

I've been lurking here for a few months now so I know how helpful and qualified ugo is, and if I ever did start another "what wheels should I buy?" thread, he'd be the first person I'd ask. Or alternatively, I could just ask the question, "how much money do I need to spend to be as fast as Lizzie Armistead?" Answer, 10 years and 10ml/kg/min.

VTech

I put my new wheels to the test this past week and y aero's are very slightly worse with a 360 degree turbo of the wheel in a wind test, and when given the extra strain needed (not that I have actually done this myself yet) during high side wind, I reckon they will overall be quite worse.
There will always be people for and against anything aero, on a cool day with little wind I am sure the aero will work well, but with a little side wind they will fair far worse than slighter rims.

yeachan153

Slowbike wrote:

I can only offer my limited experience with upgrading wheels ...

I rode a stock Allez with Mavic CXP22 rims on unbranded hubs - was fine and I could cruise everywhere at 15mph ...
It got to the end of last summer and I noticed a problem with the freehub so I decided to upgrade the wheels - I ended up with some Fulcrum racing 7 rims with FR5 hubs & aero spokes (those are the flat ones) - not an expensive wheelset by any stretch, but enough for my riding!
Anyway - what I noticed was that most of my riding didn't change - the climbs were still climbs and the flats stilled ran along nicely ... where I noticed the difference was when I got >20mph (after a descent!) and normally had to put in quite a bit of power to keep it going - it just felt easier. Difficult to quantify as there are so many factors involved, but I did get a PR on one segment straight after putting the new wheels on - probably partly helped by the tailwind and excellent timing of large overtaking vehicles....

very sceptical if it was the aero spokes that made your ride easier/faster... im inclined to think lower rim weight and freehub resistance? Also the fact that the stock allez comes with heavy wheels so you probably spun up to speed on the fulcrums faster