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Aero wheels for a small light rider

Hi guys

Am new to this forum and am hoping you guys can guide me in the right direction!

I’m after a set of new wheels. However, I don’t really know what I’m looking for. I currently have the Mavic Cosmic Elite’s which came with my bike when I bought it. This weekend just gone, I hired a set of Enve 6.7 clinchers and used them on the Ironman Wales bike course. I've only done that course once before, this time last year, but I can see from my times I was noticeably faster. That might be due to having an extra year of cycling in me though, I'm not sure. However, the wheels certainly felt faster on the flats. I'm on the small side (5 foot 1, 7 and a half stone) so hills have never been an issue for me. However, I'm generally pretty rubbish on the flats and these aero wheels seemed to make it feel a lot easier.

So, now I think I'm after some aero wheels  1 However I literally have no idea what I'm looking for! I didn't intend on getting the Enve wheels - that was a mistake with the shop. I had asked for some FFWD FR6s but they gave me the Enve ones instead because someone already had the FR6s.

I don't want to spend any more than £1k on a set but I really don't know where to start. Is my size and weight an issue? I've never used aero wheels before and they definitely did feel a bit twitchy when they caught the wind.

Any help or advice would be massively appreciated. Thanks  1

If you're new please join in and if you have questions pop them below and the forum regulars will answer as best we can.

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76 comments

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freebsd_frank replied to alotronic | 8 years ago
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Quite, just what I am going to do [go for a ride], 300km overnight Audax
on my new Ti frame. I guess I will be imagining any difference it makes
to my comfort levels and speed?

You will have to imagine your @rse isn't hurting after doing 300K already  3

Ti is an excellent material for bike frames: light, strong and corrosion
resistant. Because it's
strong , you can use fairly small diameter tubes for the frame which, along
with the materials other physical properties, means a
certain amount of give when compared with the over sized tubes used in
carbon fibre composite or Al alloy frames.
So the plush ride of Ti spoken of by riders is based on engineering fact and
not imagined.

One thing against Ti: it's expensive.
I wanted to buy a Ti frame but couldn't afford it, so I've had to make do with
a very stiff carbon composite frame.

Have a good ride!

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Iamnot Wiggins replied to freebsd_frank | 8 years ago
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freebsd_frank wrote:

I wanted to buy a Ti frame but couldn't afford it, so I've had to make do with a very stiff carbon composite frame.

You massive fashion victim!

A "very stiff carbon frame" will cost similar to a good ti frame. If you've picked up something off eBay from a Chinese seller, it's not very stiff in the slightest.

And, before you tear into me for not knowing what I'm talking about, I have ridden many miles on a cheap carbon frame from China before it failed. Compared to my current carbon frame, the difference was night & day. Just like when I compare my 35mm deep wheels to the ride offered by my hand built wheels. Just like when I ride on my 23mm tyres and then on my 25's a few days later. Funny how people can actually tell the difference between things, isn't it. Do you also think that the driving comfort of an old farming Land Rover is akin to that of a newer model of Range Rover or is that just "marketing guff" too?

Whilst your engineering knowledge it admirable and probably comes in useful somewhere, you are still quite the neanderthal.

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Mrmiik | 8 years ago
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Heyo - thought I'd chip in as I'm in a similar position to the OP. Got a couple of sets of factory builts from Miche and Campag, but my best wheels are a set of modern (wide rim) handbuilts, with a few extra spokes on the rear to deal with Flemish cobbles.

Now, I'm aware that ShortStuff84 hired a set of ENVEs... we all know that wheels are not created equal and that certainly applies to aero wheel. ENVE wheels are considered some of the best in the biz, and if you look at all the papers put out by companies, the advanced shapes of high end rims are where the benefits come into play - not by just going down the deep section route - well that seems to be the consensus. People are going to be cynical but if you look at the R&D that has gone into aero wheel development, it seems convincing that the engineers have worked to eek out performance at a variety of yaw angles... etc etc

However, some of the more open mould stuff that Planet X, DCR and wheelsmith sell seem to be catching up with wider rim and I have infact ridden a pair of 50mm wheelsmith tubs. Fast on the flat, but naff climbing - exciting and terrifying descending.

After much consideration myself - I can say that I would only go for carbon tubs - clinchers are just too heavy and problematic. Plus tubs ride soooooo nice  1

Cervelo have demonstrated that ALL riders do benefit from aero (much more than low weight in fact), but certainly its fair to say that fast riders stand the most to gain from aero wheels in particular. As the wheelsmith website says about their 50mm rim: Lift is noticeable at just 18mph and above. Although I also reckon shiny wheels do motivate people to train harder.

Aero wheels, combined with refined aero positioning on the bike, quality clothing and helmet will all add up to faster times!

Now onto a recommendation. EXPLOIT THE EURO! check out the prices of wheels on sites like bikediscount right now - we are talking sub £1000 for a set of new Campag bora tubs.  16  16  16

Seems a shame that the conversation has taken a nasty turn...

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Chris James | 8 years ago
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I got a bit bored leafing through the last post. I guess frank has a bit of a crush on Jobst brandt?

If I were frank I would worry more about the Open Pros reputation for cracking around the eyelets than whether a factory built wheel's spokes have been properly stress relieved. FWIW many (most?) 'factory' wheels are built by hand anyway. Certainly the Shimano ones are.

I have both 32 spoke and low spoke count wheels. Both are fine (i.e. the low spoke count wheels have not proved to be 'weak') and have lasted without problems for years, although as another poster recommended above I prefer a wider rim than the open pro.

I like my hand builts on my commuter and 'cross bike as they are easily re-trued and re-rimmed. I wouldn't buy a 32 spoke wheel specifically to race / time trial on - I would buy something that has been designed for racing - e.g. low spoke count, deeper section rim with a profile optimised to reduce drag across a wide range of yaw angles (yes, wind tunnel testing does look at this), wider rim to better match tyre profile etc.

In fact, even when I race cyclocross I swap out my box sections for rims that shed mud better.

The original poster said they trialled some deep section clinchers and was MUCH FASTER on the same course than the previous year on mid section alloy rims, and so was asking for suggestions for aero wheels.

frank answered that by ignoring the request completely and denying that it is possible for wheels to have any real world aerodynamic benefits over box section rims and 32 spokes. In fact, in your last post you seem to be saying that all wheels except those built by someone who has read Jobst Brandt are unsuitable for any use at all.

I don't know if this thread attracts techy types, but I am another mechanical engineer (B.Eng. + M.Sc. + 20 years in aerospace manufacture and quality roles).

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freebsd_frank replied to Chris James | 8 years ago
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I got a bit bored leafing through the last post. I guess frank has a bit
of a crush on Jobst brandt?

I'm sorry my post bored you. I guess it contained a bit too much in the way
of technical information with relevant links. Stuff you as a "professional"
engineer don't seem to find interesting. Perhaps a more suitable occupation
for you would be as a toilet attendant.

As for my "crush" on Jobst Brandt, he wrote the definitive book on spoked
bike wheels. You should read it some time before you next spout your worthless
opinions on wheels on this forum. He would have whooped your sorry @rse
as an engineer. Fact.

If I were frank I would worry more about the Open Pros reputation for
cracking around the eyelets than whether a factory built wheel's spokes
have been properly stress relieved.

That's because you're a muppet masquerading as an engineer. FYI, spokes that
haven't been properly stress-relieved will fail in no short order. Read the
link I posted, sh*t-for-brains.

As for Open Pros cracking around the eyelets. All Al alloy componentry
subjected to cyclical stresses will eventually fatigue fail because it doesn't
have a fatigue limit like steel. It's why you should change your Al alloy
handlebars if you've done a lot of miles because if you don't, you'll end up
on your face when (not if) they fail. I don't know if this was the reason that
they increased the diameter of alloy handlebars

FWIW many (most?) 'factory' wheels are built by hand anyway. Certainly the
Shimano ones are.

Hogwash. They're laced and tensioned by machine. But are they stress-relieved?
The manufacturers don't publish useful data like that, just marketing guff.

I have both 32 spoke and low spoke count wheels. Both are fine (i.e. the low spoke count wheels have not proved to be 'weak') and have lasted without problems for years, although as another poster recommended above I prefer a wider rim than the open pro.

Anecdote filling in for engineering facts. You should be ashamed of yourself
as an engineer.

What are the technical reasons for preferring a wider rim to an Open Pro?
Thought so: none, or you would have posted them.

I would buy something that has been designed for racing - e.g. low spoke count, deeper section rim with a profile optimised to reduce drag across a wide range of yaw angles (yes, wind tunnel testing does look at this),

How about a link? Not from a manufacturer (they're trying to sell something)
but somebody independent. If the engineers doing the testing are of the calibre of you, what do you rate their chances of getting anything more than worthless
data? Vanishingly small, I'd say.

The original poster said they trialled some deep section clinchers and was MUCH FASTER on the same course than the previous year on mid section alloy rims, and so was asking for suggestions for aero wheels.

You obviously think it was the exact same conditions. I'll let you into a
secret: the wind is a variable, so her anecdote is worthless; isn't it?
Engineer? There are some useless ones in any profession, I guess.

In fact, in your last post you seem to be saying that all wheels except
those built by someone who has read Jobst Brandt are unsuitable for any
use at all.

No, anybody who builds wheels in accordance with the engineering principles
and facts established by Brandt. I gave a link to Musson's book on
wheelbuilding who's wheelbuilding method is based on Brandt.
I don't need to read Principia to know that Newton was right.

I don't know if this thread attracts techy types, but I am another mechanical engineer (B.Eng. + M.Sc. + 20 years in aerospace manufacture and quality roles).

Thanks for the info. That's the last time I'm flying.

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Chris James replied to freebsd_frank | 8 years ago
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freebsd_frank wrote:

I'm sorry my post bored you. I guess it contained a bit too much in the way
of technical information with relevant links. Stuff you as a "professional"
engineer don't seem to find interesting. Perhaps a more suitable occupation
for you would be as a toilet attendant....your worthless opinions on wheels on this forum. ........That's because you're a muppet masquerading as an engineer. ...., sh*t-for-brains... You should be ashamed of yourself
as an engineer....Engineer? There are some useless ones in any profession, I guess.....Thanks for the info. That's the last time I'm flying.

Cheers for that constructive post frank.

Given your views on technical innovation I am surprised you have got round to using anything as new fangled as aircraft anyway.

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Shortstuff84 | 8 years ago
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Firstly, not that it really matters, but I’m a she not a he.

Secondly, I did not acknowledge his help because I am a brown-noser and a lickspittle, whatever that is. I posted my original question because I genuinely had no idea of where to start. I had done a Google search prior to posting my query and found the amount of information out there overwhelming. So I came to this forum to ask for advice on where to start. And pretty much everyone, yourself included, gave me advice for which I am actually genuinely grateful for. I’m sorry that you live in a world where you automatically assume someone is a brown-noser and a lickspittle just because they thank people who have given up their time to help.

You can take this however you want but I do triathlon and a small part of the appeal is all the shiny new bits of gear you can get, wheels included. I completely appreciate your view that I shouldn’t waste money on something that will not benefit me. I also take on board your comment of “I’m sorry, you’re just going to have to train harder”. I am not expecting any wheels to do the work for me. But – and this could be a complete coincidence – as mentioned, at the weekend I had aero wheels on my bike and I felt faster and it felt easier. I have a bit of spare money that I had set aside for an upgrade on my bike and this is where I have chosen to spend it.

You’ve mentioned a few times that buying into carbon wheels seems to be some kind of fashion choice. Maybe it is. I’m pretty sure buying a helmet that matches the colour scheme of my bike isn’t going to improve my performance but it does look better.

I certainly have more to go on than I did a few days ago so thank you everyone for your opinions and advice  1

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freebsd_frank replied to Shortstuff84 | 8 years ago
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Firstly, not that it really matters, but I’m a she not a he.

My apologies, it didn't occur to me that you are of the fairer sex.
I thought when you posted: "Crikey, he's bit of a weed; better not refer to it,
he's bound to have issues with it"!

As you say, your sex doesn't matter but I'm glad you, as a woman, have taken
up the sport/hobby: not enough have, IMO. You'll act as an example which
hopefully your girlfriends will follow.

Secondly, I did not acknowledge his help because I am a brown-noser and a
lickspittle, whatever that is.

I'm sorry, I mistakenly thought you were a regular poster and if I'd known you
were a woman, I wouldn't have abused you in the way that I did. I know that
probably doesn't make any sense to you and it's a poor justification but I'm of an age where such behaviour
was beyond the pale. Men on the other hand, I consider fair game. Sexist
nonsense but there it is. We are what we are.

You can take this however you want but I do triathlon and a small part of the appeal is all the shiny new bits of gear you can get, wheels included. I completely appreciate your view that I shouldn’t waste money on something that will not benefit me. I also take on board your comment of “I’m sorry, you’re just going to have to train harder”. I am not expecting any wheels to do the work for me. But – and this could be a complete coincidence – as mentioned, at the weekend I had aero wheels on my bike and I felt faster and it felt easier. I have a bit of spare money that I had set aside for an upgrade on my bike and this is where I have chosen to spend it.

I completely understand where you're coming from, cycling is much more than
dry facts and figures and technical details. A large part of it is psychology:
I know, though I've never raced, that some days I fly and others I can barely
turn over the cranks.

As you will have noticed, I tend to come from things from an engineering
perspective and you kindly thanked me for my views. If you think that your
wheels will make you faster and you can afford the money: go for it. I can't
give any opinions whether brand x is better than brand y; I'd guess that for
the amount you're spending, you're likely to get yourself a decent set of
wheels whichever reputable brand you go for. I would, like I think I said, use
a cheaper more robust pair for training; so if you trash them you're not so
much out of pocket.

You’ve mentioned a few times that buying into carbon wheels seems to be some kind of fashion choice. Maybe it is. I’m pretty sure buying a helmet that matches the colour scheme of my bike isn’t going to improve my performance but it does look better.

A large part of my original post's purpose was to save you money. I don't want
people reading this forum to think that they need expensive gear. You don't
and it's not as easy as equating "more expensive" equals "better". Often it is
but it's not always true.

BTW, the person who first posted a reply, IIRC, gave an informative link to the
opinions of an aerodynamics engineer with regards to aero gear which will make
you faster. He listed a variety of things: aero helmets, skinsuits etc. but he
didn't mention aero wheels. That suggests to me that he thinks the gear he
lists gives you a greater advantage than aero wheels.

Maybe you could buy some of the gear he suggests with your next purchase.

All the best, happy cycling and I hope you win your next triathlon (with your
new go-faster wheels)!

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Podc | 8 years ago
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I might buy some. They look cool  103

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alotronic | 8 years ago
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And lets stop this thread now shall we?

Not really helping the OP much is it?

Otherwise you should just take it to the next step old school stylee - pistols at dawn.

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Nixster replied to alotronic | 8 years ago
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alotronic wrote:

And lets stop this thread now shall we?

Not really helping the OP much is it?

Otherwise you should just take it to the next step old school stylee - pistols at dawn.

I agree entirely, I don't think either of us have anything to learn from further exchanges.

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alotronic | 8 years ago
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Well that was an entertaining read.

Being (as many people will be) an owner of 3cross 32 hand built wheels and 20/24 deep section alloy rim aero wheels (and indeed of many more wheels) I can state my *opinion* based on owning both sets for four years and *seat of the pants* and also a bit of *garminology* that the aero wheels are, not surprisingly, faster and that the 32 hand-builts feel more stable and more comfortable (not a contradiction - more spokes, round spokes and more crossing). They wheels sets cost within £20 of each other and were around £250 from memory.

The OP would certainly be better off with the aero wheels given their weight and intention. And guess what, I *change my wheels* depending on what I am about to do. I have training wheels and fast wheels. I don;t race so the fast wheels are *just for fun*. Cycling is a joy, I am allowed to indulge it in anyway I like. I have fun riding and buying and tinkering with bikes. It's not an equation.

While I share a little of the cynicism above and am a bit of a scrooge myself (I mostly buy second hand) if I did race I would certainly consider a set of carbon rims in the aero format... but only if I were Cat2 or above  3 Otherwise it's much more useful having two sets of wheels which are 'good enough' at their respective jobs.

Also worth noting that open pros have pretty much had their day, they are a good cheap training rim but not a patch on the newer wider rims from Velocity (Pacenti and so on, but I don't have those). I base this *opinion* on having ridden both, one after the other on the same hubs with the same lacing pattern and the same tyres.

Finally would recommend a good read of the DCR website as there is a lot of pretty well balanced commentary in there on relative strengths and weaknesses of materials etc.

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freebsd_frank replied to alotronic | 8 years ago
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the 32 hand-builts feel more stable and more comfortable (not a contradiction - more spokes, round spokes and more crossing).

More stable than a deep section? Possibly. You wont have
side winds catching your low profile rims as much. But on the contrary,
your probably heavier deep section rims will have more angular momentum
at any given speed and require a greater torque applied via the handlebars for
the wheel to be deflected off course.

More comfortable? You're imagining things. FYI, a properly tensioned spoked
wheel will not "give" to any significant degree. Not to an extent that you can
feel it. Doesn't matter whether your spokes are laced radially or cross,
number of spokes and section of spoke or type of rim.
The spokes are made of stainless
steel which is a strong but not very elastic material. They will stretch a bit
and return to their original shape/length, but the longitudinal stress you have to subject a spoke to, for it to visibly stretch is considerable even though a
spoke is thin. To stretch it visibly, you'd have to apply a load that would
cause the material to pass it's elastic limit ie. you'd have permanently
stretched the spoke and it would henceforth be useless. Rims don't really
come into it, their purpose is as an attachment for the spokes and tyres.
Those who say "my deep section carbon rims are so strong" are talking rot.
What your 32 crossed spoke handbuilt wheels will be though, are much stronger.
Assuming, they've been built by a competent wheelbuilder.

A long time ago I asked my LBS to build me a set of wheels. The f*ckwit,
didn't even realise that you had to use different length spokes on the rear DS
and NDS or he calculated the spoke lengths wrong. Hence, the rim wasn't
centered between the dropouts!

After that experience, I built my own. I recommend others do likewise.

Perhaps it's because of your different tyres on that wheel, you ask? No.
A racing tyre blown up to it's manufacturer's specification ie. at least
100psi, has the constituency of a rock. You can feel the gravel embedded in the
tarmac. Those who think they can tell the difference between a 23mm tyre
blown up to spec and a 25mm; they're also fantasists. Those who think brand x
feels more comfortable than brand y? Fantasists. Those who buy expensive
carbon fibre seatposts because they "smooth" the ride and are more
"comfortable"? Fantasists. There's a whole load of
them riding the TdF ATM. I saw on this site, that the journalist spotted that
one of the pros (or rather his mechanic had on his orders) had gone to the
trouble of re-branding his tyres to brand x from brand y. The pro was
obviously a fantasist who thought brand x was more comfortable/faster/better
than brand y. Yes, some tyres use grippier rubber compounds than others so you
wont get so many miles out of pair. Some are more puncture resistant than
others dependent on how they're carcassed and with what material. But more
"comfortable"? Fantasy.

This re-badging dishonesty has been going on for years. When the pros used to
ride steel frames, it was strongly rumoured that some teams whose frame
manufacturers didn't have a Ti frame in their range would use
re-badged/sprayed Ti Litespeeds!

Also worth noting that open pros have pretty much had their day, they are a good cheap training rim but not a patch on the newer wider rims from Velocity (Pacenti and so on, but I don't have those). I base this *opinion* on having ridden both, one after the other on the same hubs with the same lacing pattern and the same tyres.

So what did you notice having ridden both? I suggest you noticed nothing. Why
are the wider rims better than Open Pros? I've told you above that rims have
little to do structurally with a wheel but anchor spokes and tyres. Your
opinion is entirely bogus; you cant tell the difference between wheels with
rims of similar section and weight. Mechanically and aerodynamically any
difference is going to be so vanishingly small as to be not measurable let
alone to be noticed by the rider.

Was the problem that the Open Pros were cheap? Why have they "had their day"?
Or is it because they have been around a longtime and hence not "trendy"
enough? My opinion: Open Pros have been around for a long time because it's
difficult to improve on them and riders who have ridden them over the many
years they've been available must come back for more because they haven't
been failed by them. They recommend them to friends. They say to themselves,
these rims were cheap, why should I risk going for a newer more expensive and
untrusted brand? That's why Mavic keeps making them. You've no idea of the
tooling costs of making a different section Al alloy rim. It's considerable.
Why tool-up when your product is still selling? It doesn't make economic
sense.

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fukawitribe replied to freebsd_frank | 8 years ago
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freebsd_frank wrote:

Those who think brand x
feels more comfortable than brand y? Fantasists.
..
Yes, some tyres use grippier rubber compounds than others so you
wont get so many miles out of pair. Some are more puncture resistant than
others dependent on how they're carcassed and with what material. But more
"comfortable"? Fantasy.

Frank, when you think about the logical consequences of what you've just written I think, I hope, you'll realise that it's clearly nonsense and reconsider... perhaps you've been listening to Beastie too much  3

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Martyn_K | 8 years ago
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Cheers Nixster. Next we will discuss in the inherent strength of the plate that his ar$e has just been handed to him on.

Back to the OP.

Do a little research. Talk to some humans about their experiences. Take any advice on the internet with a pinch of salt. If possible hire some more wheels.

Most importantly, do what YOU think is right for YOU. If you have money to spend then spend it on what you like. If you make a purchase which is biased towards looks, fine. If you make a purchase biased towards performance, fine.

The bottom line is ride your bike. Enjoy riding your bike. Have fun riding your bike.

Out.

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Nixster | 8 years ago
0 likes

Sorry, how rude of me, you asked for a response on some 'facts' and I assume from an 'engineering' point of view.

1 aero wheels are weak: there is no inherent reason why this should be the case. Wheels with a lower spoke count will be less robust all other things being equal, however all other things are not equal. Deeper sections will have higher Section modulus and therefore resist bending better than shallow sections. The material is likely to have a higher tensile strength as carbon is normally used in preference to aluminium, although it may be more brittle. But more importantly, in the world of engineering we are normally trying to optimise conflicting requirements. The OP weighs 7.5 stone and proposes to use them for triathlon races. This suggests that strength is not the overwhelming priority for the intended use, so 'strong enough' should be well within the capability of well made aero wheels.
2 aero wheels are not very aero in most conditions: there's pretty good evidence that they are more aero most of the time than box section rims, so I assume what you're getting at here is that they're not aero enough for enough of the time? I think that's up to the purchaser but again looking at the intended use, triathlon, drafting is illegal, courses are usually not mountainous and the handling issues are limited because there is no bunch racing so if there is a situation where the benefits are most likely to be realised this is probably it.
3 they're expensive: my first suggestion costs £400, roughly the same as your hand built open pro example. And there are non aero options up to the £1k limit given. So no, not necessarily. You can go cheaper than that if you're willing to compromise on weight but given the budget available, there seemed no reason to. They certainly can be expensive like most things but it's not a given.
In an engineering sense I think where you went wrong was to ignore the brief. It's a tendency we engineers have to be vigilant against.

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freebsd_frank replied to Nixster | 8 years ago
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Sorry, how rude of me, you asked for a response on some 'facts' and I assume from an 'engineering' point of view.

That would be nice. As a CEng I would value your perspective on the matter
rather than the name-calling and pop-psychology.

1 aero wheels are weak: there is no inherent reason why this should be the case. Wheels with a lower spoke count will be less robust all other things being equal, however all other things are not equal. Deeper sections will have higher Section modulus and therefore resist bending better than shallow sections.

The strength of a spoked wheel lies overwhelmingly in it's spokes, they are
in tension and the section modulus of the rim doesn't really come into it. You
just need it strong enough that the spokes don't pull through the eyelets on
the rim. I believe, that carbon fibre composite rims have re-inforcement at
the eyelets to stop spokes pulling through when they're tensioned, during
the wheelbuilding stage or when out riding.

Aero wheels are weak because they are generally radially laced (which is not
as strong as conventional crossed lacings, although they're crossed on the
drive side rear, for obvious reasons) and they use too few spokes. The fewer
the spokes, the weaker the wheel. As I said in a previous post, my Khamsins
are only rated for riders of no more than 82Kgs - that's a weak wheel. They're
medium section but 20 plain gauge spokes (butted or bladed spokes have a
higher Young's modulus as they have been work-hardened in the forming process)
radially laced. Radial lacings with lower spoke counts also mean that the
spokes are in much higher tension. Campag Record hubs can't be built radially
because the flanges fail. You have to use something beefy like steel forged
hubs. Because of this high spoke tension, you also need a stronger rim which
in practice means heavier.

You say that a deep section wheel will resist bending better than a lower
section rim. While true, composite carbon fibre is a very brittle material and
for all intents and purposes it will fail before it bends to any degree.
With Al alloy, as long as you stay below it's yield strength you won't put a
"set" into it. Go over it and you will. I prefer the behaviour of Al alloy in
practice: go down a pothole and you may bend the rim and break the odd spoke
or two. With the carbon fibre, if the stress isn't along the lay-up of the
fibre, then you're largely dependent on the polymer it's embedded in for
strength ie. nothing like as strong as the Al alloy.

Have the engineers: manufacturing and
mechanical, working for the wheel manufacturers done all their homework about the various stresses in a wheel?
Have they read Brandt's "The Bicycle Wheel"? I don't know. As a CEng, you must
have come across people everyday who haven't done their homework. Who was the
engineer who thought about using carbon fibre composite for spokes? They failed
catastrophically; they obviously hadn't read Brandt.

A link to Brandt's obit on this site (he unfortunately died recently):

http://road.cc/content/news/150563-rip-jobst-brandt-author-bicycle-wheel...

If you think I'm rude, you obviously never read Brandt on usenet. He would
batter any clueless newb or fashion follower into submission with engineering
and scientific fact. Never saw him bested; he knew his onions when it came to
engineering.

There's an archive of some of his writings at Sheldon Brown's site:

http://sheldonbrown.com/brandt/index.html

Read what Sheldon Brown has to say about the Spoke Scam:

http://sheldonbrown.com/wheelbuild.html#spokes

Somebody posted earlier about their spokes failing on their fairly cheap
wheels. Almost certainly because the wheels were factory made and the spokes
not being stress-relieved in the building process:

http://sheldonbrown.com/brandt/stress-relieving.html

My advice to the poster is build your own. I use Roger Musson's instructions
(Roger has read Brandt):

http://www.wheelpro.co.uk/wheelbuilding/book.php

2 aero wheels are not very aero in most conditions:
there's pretty good evidence that they are more aero most of the time than
box section rims,....

Have you got a link for that? If it's wind-tunnel testing, have they tested
when the wind isn't straight on to the wheel? Which it is most of the time if
you're not on a track or in still conditions. I don't know if you know
anything about sailing but I think it might be a comparable situation
where you get what's called "apparent wind" which is the wind you get
if you add that created by the boats forward velocity to the existing wind.
Anyway, the action of the sails and the keel results in a vector of forces
being set-up, with a forward component driving the boat along. Of course, you
can trim sails, tack and alter the boat's course. None of which you can do on
a bike.

so I assume what you're getting at here is that they're not aero enough
for enough of the time?

Very much so.

I think that's up to the purchaser but again looking at the intended use, triathlon, drafting is illegal, courses are usually not mountainous and the handling issues are limited because there is no bunch racing so if there is a situation where the benefits are most likely to be realised this is probably it.

IIRC, the triathlon bike stage is about 40k. If it's windy and the course
is winding or loops back on itself, then the wind is going to be coming from
all sorts of directions. I don't know if deep section rims would be any
advantage in those circumstances.

3 they're expensive: my first suggestion costs £400, roughly the same as your hand built open pro example. And there are non aero options up to the £1k limit given. So no, not necessarily. You can go cheaper than that if you're willing to compromise on weight but given the budget available, there seemed no reason to. They certainly can be expensive like most things but it's not a given.

I don't know if the expensive wheels are that much better than the cheaper
ones. They all use radial lacings with few spokes with the
disadvantages that brings: weaker, heavier rims and hubs. The expensive ones
seem to use butted or bladed spokes: an advantage not for the minimal aero
gains but because they have a higher E and UTS so less likely to fail. But do
any of these machine laced spokes get properly stress-relieved? Or do they
just go round with a tensiometer and say: job done.

I'll stick with my handbuilt Open Pros 32 spokes 3x. I know they've been built
properly and will last and I still think the OP would be better off with them
too. It's an unfashionable opinion but so be it.

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hampstead_bandit | 8 years ago
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I've spent some time this year riding a variety of bikes from Giant (I work at a Giant brand store) including the Defy Advanced (disc), TCR (race) and Propel (aero race).

I've used 2 different Propel, the mid range with the carbon/aluminum deep sections, and the bike below with the full carbon wheel. I've also experimented using low profile aluminium wheels from the TCR in the same bikes, when its been very wet / windy.

//ep1.pinkbike.org/p6pb12338129/p5pb12338129.jpg)

I don't claim to be an expert, I don't race. I do like riding fast whether its climbing hills, descending hills or on the flat - I have Regent's Park less than 1km from my house in NW London which is ideal for fast flat sessions.

The aero wheels are very noticeable in terms of straight line speed, and maintaining a high speed once moving. Once moving fast, the wheels make a cool humming noise!

Acceleration is slower than the low profile wheels, obviously.

The full carbon wheel accelerates faster than the carbon / aluminium wheels, as the lighter weight (approx 200 gm) than the carbon / aluminium wheel is very noticeable. It also feels stiffer in terms of side to side flex. All the wheels have DT Swiss 240 internals so similar pick up.

The carbon / aluminium is much better behaved in wet weather as it has a regular aluminium brake track; the full carbon wheel works much better braking in the dry. Both aero wheelsets can be a handful in blustery conditions, but you get used to maintaining a firm grip on the bars!

If you are getting aero wheels, I'd look carefully at spending a decent amount to get a quality wheel set, and research the support you will get from the distributor in terms of spare parts and repair; as this makes 'ownership' of your wheelset much less painful.

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Nixster | 8 years ago
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Carbon clinchers are fine on long alpine descents as long as you don't use the brakes...

Carbon rims don't deal well in general with heat from braking. On long alpine descents, particularly if you brake for long periods rather than just for the bends, heat builds up in the rims. This affects the resin in the CF composite, weakening it. With clinchers you are reliant on the rims to stop the tyres blowing off, potentially explosively, so weak rims are a bad thing. There's a double whammy as the increased heat also increases the pressure in the tyres compounding the issue. Having said all that there are ways of mitigating this by pulsing rather than dragging the brakes and the top brands are on top of if not completely resolved the problem. You could of course just stop from time to time to let everything cool down.

Tubular wheels aren't reliant on the rims to keep the tyres on, they use glue and the pressure stress remains in the tyre because they are, well, tubular. So less of an issue in terms of catastrophic failure but if the resin is breaking down due to heat that still isn't a good thing. So apply suitable braking technique as before.

Are tubs the better option? Another tribal issue this one. In general they get you a lighter wheel & tyre system because the rim doesn't hold the tyre together. This is particularly true with carbon rims because of the direction specific nature of its material properties. Tubular tyres suffer fewer punctures as they don't pinch flat readily. In carbon rims, particularly deep section ones, tubs can be cheaper as they are easier to make. Zipp 303 are about £1.5k tub £2.2k clincher, round numbers. There's a host of other stuff which is more subjective and amounts to 'tubs are nicer'. Downside is fitting the tyres in the first place, although using tape not glue makes that easier, and dealing with punctures. For event or 'best' wheels at aero rim depths, and with you being light weight I would say tubs are the better option but not everyone would agree.
Hand built vs factory built is an article of faith thing. Some factory wheels are machine laced and hand finished so it's not cut and dried but price wise it can be cheaper and you can get a custom product tailored to your needs and you can get better customer service and maintenance post purchase. After that it's back to subjective 'hand builts are nicer' arguments.

I really should get out and ride my bike more  17

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Shortstuff84 replied to Nixster | 8 years ago
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This is super helpful, thank you  1 I'm pretty sure I could smell burning when I was braking hard over the weekend so that makes sense now! I guess if I did go for tubs, it'll just take practice. Touch wood, I've only ever had one puncture. Might be luck, or maybe its hard to get a puncture when you ride as slow as I do  21

And yes, you should get out and ride your bike more  1

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Shortstuff84 | 8 years ago
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Thanks again everyone for your input, really appreciate it. Lots of options to consider so I definitely have somewhere to start now.

I hadn't realised there was so much to consider. Must admit before I posted I was going to see what had the best/most reviews on wiggle!

I'm going to email DCR to see what he suggests. I don't know if I'm getting this wrong but it almost seems like the handbuilt wheels are cheaper than factory built? How does that work?

I do like the look of the cero wheels so a definite possibility  1

Also, again please excuse my lack of knowledge but why would you not want to use carbon clinches on long alpine descents? Are tubs always the better option, assuming you know what you're doing with them?

Thanks again guys x

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freebsd_frank replied to Shortstuff84 | 8 years ago
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Also, again please excuse my lack of knowledge but why would you not want to use carbon clinches on long alpine descents?

I think he's referring to carbon clincher rims.

They heat up and can fail:

http://www.bikeradar.com/gear/article/are-carbon-fiber-clinchers-safe-34...

In that article, there is a lot of hand-waving by the Reynolds spokesman:

Aguero said Reynolds’ heat failure rate is “less than 1 percent.”

Yeah, but what he doesn't mention is that probably <1% who buy their wheels go down Alpine passes with them ie. a 100% failure rate.

You might also want to look at:
http://www.wheelbuilder.com/faq.php?q_id=10

Aluminum braking surfaces generally stop in all weather conditions and do not require special brake pads. Carbon braking surfaces require special brake pads, do not stop as well in wet weather, and are more sensitive to overheating under heavy braking conditions.

I forgot about them being crap in the wet in my original post

This though from the same FAQ, sums it up:

Beauty is in the eye of the... , however we all agree those carbon wheels look cool on your bike.

Translation: they're an expensive fashion accessory.

Don't believe the bogus wind-tunnel testing. In most conditions they are not
going to make you go any faster. Even in ideal conditions, on a straight
course with no hills or cross-winds, the gains are marginal in the grand
scheme of things.

I'm sorry, you're just going to have to train harder and for that you need a
robust set of wheels. When training it doesn't matter a damn how heavy or
non-aero your wheels are. In fact, it's an advantage (more resistance).

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Nixster replied to freebsd_frank | 8 years ago
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freebsd_frank wrote:

I'm sorry, you're just going to have to train harder and for that you need a
robust set of wheels. When training it doesn't matter a damn how heavy or
non-aero your wheels are. In fact, it's an advantage (more resistance).

Hey freebase frank, if I buy 32 spoke 3 cross open pros like you say will I become an obnoxious, self opinionated @rse too?

OP didn't ask about training, or training wheels but about aero RACE wheels. for the RACES they plan to do. If you don't have anything constructive to say on the topic, why not put the computer down and go out and train. Or are you just a troll?

6 posts and look how many friends you've made.

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freebsd_frank replied to Nixster | 8 years ago
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Nixster writes:

Hey freebase frank, if I buy 32 spoke 3 cross open pros like you say will I become an obnoxious, self opinionated @rse too?

No, you already are one. But you'd save yourself some money by not following
the rest of the fashion victims on here.

OP didn't ask about training, or training wheels but about aero RACE wheels. for the RACES they plan to do. If you don't have anything constructive to say on the topic, why not put the computer down and go out and train. Or are you just a troll?

And I told him my opinions and facts about aero wheels and gave him some links
to other sites. On the contrary, WTF have you done? Attacked me for giving my
opinions on the matter.

And you suggest I'm a troll? Don't you know that when you point the finger,
you've got 4 pointing at yourself?

How about addressing some of the facts about aero wheels: they're weak,
they're not very aero in most conditions, they're expensive.

Yeah, the facts hurt don't they when you've (at great expense) bought into
the aero wheels myths as pushed by the manufacturers. I can imagine that you
feel a little bit sore after being scammed out of £100s because you're a
know-nothing but do try not to let it show.

6 posts and look how many friends you've made.

ROFL. You think I care how many "friends" I make on here? FYI, I don't give a
rat's @rse. Life's not a popularity contest.

I just give my opinions and state the facts from an engineering point of view;
I've studied mech/man engineering, WTF have you done? Oh yeah, bought an
expensive pair of aero race wheels in the misguided belief that they'll
mystically make you go faster. That suggests you're an ill-informed blowhard with more money than sense.

And you shouldn't care about being popular either but you obviously do: an insecure manchild. You're not the only one on here,
as evidenced by the way your post got modded up by the rest of the sheeple.

Go and read Jobst Brandt. He used to post on rec.bicycles.tech. Grok what he
has to say about wheels and then come back to me with some considered facts
and opinions.

Until you can hold your own in a technical discussion, you should just b*gger off, you muppet.

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Nixster replied to freebsd_frank | 8 years ago
0 likes

Some facts for you:
I don't own the wheels in question, I never said I did. I offered some opinions relevant to the question based on my research. I sought to help which was graciously acknowledged.

I have a degree in engineering, I am a chartered engineer, I am a director of one of europe's larger engineering consultancies. I don't struggle in technical discussions, it's what I am paid to do.

Some opinions:
I don't particularly care about being popular but I do care about common courtesy and reasonable manners. I challenged you as you seem not to care for these aspects of normal social interaction. The technical term for someone who has no regard for others opinions or feelings is 'sociopath'.

I would agree that there is some mixed evidence around aero wheels, reading the results posted by Flo shows that. But the evidence is just that, mixed and doesn't support your 'all aero wheels are a con' point of view. Take a moment to read what I posted- I never said aero wheels would make the OP faster.

Where we disagree is that you have ignored the original post, made numerous unchecked assumptions, pushed your own viewpoint to the exclusion of all others and aggressively attacked those who disagree with you.
I find aggression is often the result of insecurity, personally.
Enjoy your bike riding.

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freebsd_frank replied to Nixster | 8 years ago
0 likes

I don't own the wheels in question, I never said I did. I offered some opinions relevant to the question based on my research. I sought to help which was
graciously acknowledged.

Your "research" such as it was, seems to have consisted of going to various
online cycling shops and finding wheels within the original poster's budget
and telling him without even posting a link(s).

Your "opinions" seemed to consist of nothing more "than brand x is cheaper
than brand y which costs z."

I sought to help which was graciously acknowledged.

He acknowledged your help because he's a brown-noser and a lickspittle and
you're a regular poster, not because your "research" and "opinions" were of
any particular use. I'm sure the OP can use Google too.

I have a degree in engineering, I am a chartered engineer, I am a
director of one of europe's larger engineering consultancies.
I don't struggle in technical discussions, it's what I am paid to do.

If you're a CEng and don't struggle in technical discussions, then why don't
you discuss the technical merits of deep section rims and their low spoke
counts? Or do you know SFA about it? If so isn't it about time you informed
yourself before telling somebody to blow £1000 on a set of weak wheels?

I don't particularly care about being popular but I do care about common courtesy and reasonable manners. I challenged you as you seem not to care for these aspects of normal social interaction. The technical term for someone who has no regard for others opinions or feelings is 'sociopath'.

If you don't particularly care about being popular, why do you play to the
peanut gallery? As for caring about common courtesy and reasonable manners,
I've never heard such hypocritical BS. Who was it who wrote:

Hey freebase frank, if I buy 32 spoke 3 cross open pros like you say will I become an obnoxious, self opinionated @rse too?

It was you, you muppet. The self-regarding hypocrisy is staggering. You should
be thoroughly ashamed of yourself with posting such hypocritical guff but I'm
sure you're not.

Where we disagree is that you have ignored the original post...

I replied to it with my opinions and technical arguments with regards to deep
sectioned rims using low spoke counts laced radially. You, a CENG, haven't.
You just abused me and then in a latter post said such behaviour was abhorrent
to you.

I find aggression is often the result of insecurity, personally.

I didn't come on here to hear your blatherings on pop-psychology, stick to the
engineering and try and post something worthwhile reading next time.

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edster99 | 8 years ago
0 likes

Free speed = tubulars. Less weight to get rolling, more compliant, not as much hassle as people imply (due to having no experience of them and being scared of them). Whatever you buy, you'll get more performance with a tubular version. And if you ever want to do long alpine descents, you won't want to be using carbon clinchers, based on my and several people I know's personal experience.

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fukawitribe replied to edster99 | 8 years ago
0 likes
edster99 wrote:

Free speed = tubulars.

Well speed perhaps - lovely ride quality, often - but 'free' ?....

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bechdan | 8 years ago
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someone else has already mentioned DCR and I would second him as a wheelbuilder.
Go on his website and send him an email with your requirements and your current bike spec. Give him an idea of what you are looking for and your budget and Im sure he will give you some good options.
Ive got two different wheels by him and after 3 years neither need any truing.

Spokes are often not given that much consideration when choosing a wheel but at speed they do add a lot of drag. Certainly having fewer spokes helps with this but the spoke profile does also. I opted for Sapim Laser on mine and am certain they help reduce drag.

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Martyn_K | 8 years ago
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I had a few months of researching deep section carbon wheels with a £1k budget earlier in the year. It is indeed a minefield. I ended my search by buying a pair of Cero RC45 wheels from Cycle Division. At £800 they are below your budget and when i got them i even got a free pair of Conti race tyres.

I have been riding them now for a couple of months and i am really happy with them. Good pick up from a standstill, great speed retention, very stiff with good response in the corners and in cross winds they are not too bad (<20mph wind). They even climb very well in comparison to a set of lighter, low profile rims i also own.

Cycle Division themselves were very good too. I had some queries that they answered both in email replies and also in person on the phone. When i ordered them i got next day delivery for the nominal p&p charges. A worry free purchase process and i'm sure there will be no problems sourcing spares when the time comes.

That's my experience, i'm sure others will be along with theirs.

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