Newbie – Why aren’t Aero section rims good for climbing?

PaulBox wrote:I’ve been told

PaulBox wrote:

I’ve been told that aero section rims will improve average speeds on the flat by between one and two miles per hour, is that bull?

If you want aero wheels because they are shiny and everyone wants them, get it. But for the majority of normal people riding around they offer very little to no increase in performance. If you have money to throw around you are better off getting some lighter wheels. OR you have enough money to get wheels that are both light and aero.

i live in plymouth, and i
i live in plymouth, and i have ridden 50mm carbons for the last 7-8 months. they look AMAZING!

(see my pic on the bikes stickey, tcr with 50mm near the bottom of the list)

but i am getting rid of them asap to get some rs81 or something similar as they are terrible in the wind, verging from annoying if you want to say take your armwarmers off to down right lethal in strong coastal winds.

and no im not a chopper, i race and have ridden for 20 years.

on a wind free day they are great, best things ever! sound amazing and all that.

but there are 2-3 routes which are always dogged with a perma cross wind and holding a straight line sucks the fun out of my ride.

i say buy them if your area is not inherintly windy but if you live anywhere windy like fecking plymouth dont waste your time

I wouldn’t buy expensive bike
I wouldn’t buy expensive bike kit based on manufacturer claims, I’m not sure anyone is that stupid are they?

I also wouldn’t base decisions on wind tunnel figures. You simply can’t factor in real world and human factors.

The idea that anyone would neglect their own training or technique and rely on expensive equipment ‘to make them go faster’ is also pretty patronising in this debate, to be honest. Yes I like my carbon wheels, and I disagree with the ‘you won’t notice the difference’ brigade, that doesn’t mean I’ve bought some manufacturer BS or am relying on expensive gear to make me go faster.

I’ve just put on my summer wheelset and it’s improved my ride and speed to a significant extent -ie I notice the difference and I’m setting my fastest average speeds of the year now.

I’m not claiming they’d be right for everyone, but certainly wouldn’t be so dismissive of a different opinion like some are on here

Simon E wrote:The numbers are

Simon E wrote:

The numbers are from wind tunnel tests of just the wheel and tyre. The aero effects still exist at lower speeds since physics doesn’t change from 15mph to 25mph. But I agree, it’s meaningless for general riding.

It’s strange how the ‘you have to be going fast to benefit’ thing is so often repeated when it’s not the case, as you can see with a play on here:

http://www.cyclingpowerlab.com/componentaerodynamics.aspx

vorsprung wrote:the lower

vorsprung wrote:

the lower rotational weight, especially on climbs is helpful. For beginners this is more likely to be the case. So it’s possible that light wheels could actually give someone with a poor pedalling style a small but measurable advantage on climbs.

Measurable? I doubt it. We’re talking about tiny micro-accelerations within each pedal stroke. An improvement in pedalling technique (and choice of gears, if possible) will be far more beneficial. Lighter, fast rolling tyres and lightweight inner tubes would be a better bet.

vorsprung wrote:

Secondly, the 1%-1.5% figure for aerodynamics only applies for time trialists moving at 25mph+ who have presumably already adopted an aerodynamic position. For general riding any effect is unlikely to be noticeable at all

700c wrote:

It’s basically personal opinion. This has been covered many times before and there are a couple of usual suspects here who always come out against aero/ lightweight wheels – or perhaps the idea of someone else spending what they consider to be a lot of money on equipment.

It’s not my opinion, the numbers are consistent across a wide number of sources. We all like shiny kit but just because brand X says their wheels are fast/light/whatever doesn’t mean you just buy it and automagically go faster.

It’s basically personal
It’s basically personal opinion. This has been covered many times before and there are a couple of usual suspects here who always come out against aero/ lightweight wheels – or perhaps the idea of someone else spending what they consider to be a lot of money on equipment.

Try them, see if they make a difference for you. Certain manufacturers – and possibly some good bike shops – will have a try before you buy policy

Simon E wrote:Firstly, let’s

Simon E wrote:

Firstly, let’s dispel a couple of myths: lightweight wheels will not make much difference to your climbing and aero wheels will not noticeably improve your speed on the flat.

A lighter wheelset may feel a bit nicer but it won’t have much effect on the time it takes. If you’re on the heavy side then the percentage of all-up weight saved (which is what really matters) is miniscule.

As for aero wheels, even at 25mph you’re looking at going 1-1.5% faster compared to a traditional 32-spoke box section wheel. A semi-aero rim (25-30mm) with ~20 spokes that is common now is likely to gain you at least half of that. American Classic 430, Bracciano or any number of others would do the job but after reading more wheel discussions than I care to count I’d get a handbuilt set with something like H Plus Son Archetype or Velocity A23s.

Unless your wheels are worn and need replacing I’d spend the money on a week riding somewhere nice. Riding your bike lots will do more for your fitness and enjoyment than all the bling in the world ever could.

I basically agree with this and I’m glad someone has explained more about this type of wheel! However I have a couple of cavets with your excellent reply.

First, there is an argument that if you do not have good souplesse (smooth regular pedalling style) then wheels do have micro accelerations all the time. Pedalling style is likely to be worse at high power input, such as when ascending. This effect is plain to see when using an inappropriate gear on a slope as the bike lurches forward with each downward stroke.

This means the the lower rotational weight, especially on climbs is helpful. For beginners this is more likely to be the case. So it’s possible that light wheels could actually give someone with a poor pedalling style a small but measurable advantage on climbs.

Secondly, the 1%-1.5% figure for aerodynamics only applies for time trialists moving at 25mph+ who have presumably already adopted an aerodynamic position. For general riding any effect is unlikely to be noticeable at all