Aero Wheels
 

So I have been wondering what the whole deal is with aero wheels and their advantages. Specifically which wheel is more needed to be aero. I like hills and want top performance there, but why not try for better in both areas.

With that in mind I am curious, if I only did one aero wheel to keep the general weight down which would be better? Front or back? I ask this because TT bikes seem to do deeper dish or disk in the back, not the front.

So my real question is would there be an advantage to put an aero on the front, and keeping the climbing wheel on the back?

In general, if you are going for hills mainly, you should go for light wheels and then worry about their aeroness if you can still afford it.
I guess 303's or 404's tubulars are about as aero as you can get while still remaining very light.
Mixing wheels for climbing doesn't make a lot of sense and it is generally accepted that the deeper wheel should go rear ... the total weight will remain about the same overall any way you place them.

People go deeper in the rear because you can go super deep (like a disc) without affecting your handling. Unless you're only doing a hillclimb time trial aero wheels will trump lightweight. Of course a set of 404s is very aero and very lightweight, so you can get the best of both if you have the money.

Changing to an aero wheel in the rear will lower drag by ~75% of what would be seen putting the wheel in the front. Riders put a deeper wheel in back because the rear wheel does not affect steering stability, and adding surface area to the rear actually makes the bike more stable.

Two comments: first you might want to check out analyticcycling.com to see how little effect wheel (or bike) weight has on performance especially compared to reduced drag, and second, deep dish is for pizza. Wheel dish refers to the different spacing from the centerline for the right and left flange on the rear hub.

Generally, aero trumps weight unless you only ride uphill.

I recently purchased a set of Easton EC90 Aero wheels, full carbon, clinchers, campy, weigh in at about 1500 gm mol. Immediately have noticed 1.5-2 mph average speed on 50-75 mi ride. Rode the Hotter'n Hell 100 yesterday in Wichita Falls, Tx 5 of us went 100k in a five man line the whole way, averaged right at 22 mph. Today we went and climbed Mt Scott in the Wichita Mts near Lawton, OK, about 1000 ft vertical in just over 2 miles. Rode the same wheels, they climb very well also. I also believe it has been said that aero trumps weight even going up hill.

Oops 1.5-2 mph increase, sorry. At 1.5 mph aero not much help

let me take this a step further and see if anyone can estimate quantitative data.

I have a wheelset with fusion rims, circus monkey hubs and 32 spokes. they weigh in at 1575grams. to me that is light cuz i'm a clyde and I have another wheeset that is 2200 grams. What kind of performance improvement could i expect going to something like a 88mm carbon tubular rim 20/24 spokes? and for the sake of argument lets say they weighed the same just the profile changed to 88mm from 27?

The reason i ask is that as I do research on stuff it seems like I can go with some deeper carbon tubulars and go lower spoke count and get really light wheelsets that will still be clyde friendly. I'm not afraid of taiwan carbon, too many good experiences my self with a couple of items and a lot of research tells me the particular supplier i'm considering has a solid rep. I'm just wondering do aero spokes make that much of a difference vs a dt comp/ revolution? keeping cost down is also a big part of this and going with bladed spokes definately pops the price up.

so what everyone is saying that aero wheels are worth it eh? if you can handle the cashola...

What kind of performance are you after?
Are you wanting to shave about a second per kilometer to do better at your next time trial?
If that's the case: go for it.
If you're expecting anything drastically more than that you're in for a dissapointment.

That's VASTLY higher improvement than even the wildest marketing claims of the manufacturers! If you look at manufacturers' claims, the boldest claims are talking around 40 seconds improvement in 40km on a flat course on a TT bike at 26+ mph -- about 0.29 mph. At lower speeds, the improvement CLAIMED by manufacturers is less or even nonexistent.

And also, the manufacturers only say aero trumps weight IF the wind direction, relative to the bike, is within a certain narrow range. Otherwise, you're just carrying more weight.

(I suspect they would like to hear your testimonial.)

Never underestimate the power of placebo.

My new 58mm carbon clinchers haven't done much to increase my average soloing speed, but that's okay since I didn't expect them too.
My goal was to have them give me a 1-2% increase in aero advantage in a group. This 1-2% will help me stay with the group longer and in turn give me a much better workout, which in turn will help me gain more fitness, which in turn will make me faster. Sheesh.

Sidenote: I did notice I was able to hold my speed at lot easier on Saturday with my 58mm wheels vs my 30mm wheels. Usually when I fall off the back I slow down to 18-20. On Saturday I was able to hold 21-22 mph. I can't say for certain the 58mm wheels are to thank for this, they probably only helped a small amount.

As AdelaaR said above, they certainly bring a nice placebo effect. :)

This.

And this.

But not this.

For reference, an increase in speed from 20 to 22MPH takes about 30% more power. You definitely won't get that much help from a set of wheels.

For climbing, you really don't need aero wheels. You are better with lighter weight rims.

But, if you want them because they look cool, you could do a shallower rim, something in the 38-45mm range, that will still be light and aero.

As for only buying one wheel, you will get more aero advantage having a deeper front.

The reason you see others with very deep rear wheels is that handling is less affected by a deep rear than by a deep front. But the front wheel is cutting through the wind. Also, it looks funny to have a deeper rim on the front.

I have Dura-ace c24 tubeless wheels which are over a pound lighter than my Zipp 808 clinchers. The Zipps are 3-5 mph faster on downhills and 2-3 mph faster on the flats. Up hill I can't tell much difference. Lighter is better uphill but 1 pound is the weight of one water bottle. Can you tell how full your water bottle is going up hill. Aero trumps light weight most of the time. For ever uphill there is a down hill, same up faster down equals faster.
So I ride my Zipps most of the time. They only have 14,000 miles on them so I don't know how they will hold up.

I live in nyc which is mostly flat. I have a set of "lightweight" wheels that are 1575 grams but not an aero profile. Because i'm 240lbs I have to be wary about going too much lighter that. Research tells me that tubular rims are stronger than clinchers so whether it be alloy or carbon I could go with tubulars to save some weight and keep strength up. FWIW, I do a decent amount of rides between 50-100+miles in length so the long duration aero wheels could make a difference. at the same time being 6'3" 240 doesn't make for much of an aero body shape so I wonder if wheels will even provide ANY help.

I don't expect miracles but small performance improvement at reasonable price is what i'm looking for. my research tells me that 60 or 88 mm profile carbon rims are heavy rims but they will be strong so even as a clyde I can go with 20-24 on the spokes and be okay. others have said that even at my weight a 38 or 44mm carbon tubular will still be plenty strong. If the aero advantage doesn't matter much, I'd rather go as light as I can because I notice a huge difference between my 1575gram wheelset vs my 2000+gram set

And miscalibration of the cycling computer. Changing wheels will "increase" your average speed if the circumphrence of the new tire wheel combination is smaller than the wheel you replace, and you don't recalibrate.

Indeed :)

Aero wheel look cool and sound nice. That's about it for us mortals. Performance improvement is small at best. I ride aero wheels daily, and I am regularly desctryoed riding and racing by those with normal wheelsets. That said, if you can afford a nice set go for it.

If you're looking for performance at a reasonable price, wheels isn't it I believe because wheels are extremely expensive for only a minor improvement.
Your position on the bike is the deciding factor ... especially if you are quite big as you say.
Consider dropping your handlebar or getting an aerobar for the biggest gains.
Even a simple thing like a more aero helmet could possibly have more benefit than wheels in your case at a fraction of the cost.
The best upgrade is upgrading your engine and if possible losing weight ... I'm going to upgrade my engine this winter and next spring :)

Ordinary mortals would be lucky to gain 1/3 mph with aero wheels. On the other question, the counter-intuitive answer is the back wheel gives you more advantage if I recall correctly. Also as the front wheel becomes more aero - disk, blades or whatever, it will become incrementally more skittish with the increased lateral area.

was wondering about that :beer:

Unless the bearings in the old ones were really bad, right? and I mean like no longer round and no grease, chunky kind of bad.