Gear

What’s the point of carbon wheels?

Carbon wheels are all over the place these days. But what do they do? And why would you want some?

Carbon wheels are everywhere. Well, not everywhere, they’re not on cars, for example. Or cats. But in cycling, it seems like carbon wheels are one of the must-have accessories for the serious cyclist. Or even the semi-serious rider. But why?

Why are they so popular? Why does it seem like everyone wants a set? And are they really a worthwhile purchase, or would you be better off spending your money elsewhere?

Fundamentally, there are three basic factors people think about when they buy carbon wheels. They’re outlined below and I’ve taken a look at the reasons why you should – or shouldn’t – part with your hard-earned cash. Or stolen cash. I don’t judge.

There are three main reasons why people buy carbon wheels: they’re lighter, more aerodynamic and, quite frankly, just look cool (Pic: Nils Nielsen)

Reason one: they make your bike look cool

I can’t decide whether this is the best or the worst reason of the three, but that’s okay. And you can admit it. You like carbon wheels because they make your bike look cool. Hell, I like carbon wheels because they look cool and I’m paid to say all sorts of significantly more erudite things than ‘they do look wicked, don’t they?’

The thing is, carbon wheels are the tool of the pro. Or, at least, the very serious amateur (the racer, basically). For anyone who doesn’t pin a race number on, there’s no need to buy a set of carbon rims other than the above. That is to say, no need other than the fact that you want them. And actually, there isn’t really a much better reason to buy anything than because you want it.

Why would you want your bike to look like this? Why would you NOT want your bike to look like this…

I mean, I once bought a Caisse d’Epargne jersey and matching shorts because I wanted them. And you know what? I enjoyed it. And that was despite the fact that even though I looked a little like Alejandro Valverde I didn’t ride much like him. And he has way more Monument victories than me. But I have way more hair than him – so we’re basically equal. Anyway, the point is, a lot of people might say that I shouldn’t have bought that kit because I didn’t need it. But I liked it, and it made me want to ride my bike more, and anything that makes you want to get out and ride can’t be bad thing.

Unless, of course, you like to ride places and commit crime then ride home. That’s an example of really bad motivation to ride. I don’t suppose that applies to 99.9 percent of you, but it’s possible to find scenarios in which riding isn’t always good is what I’m saying.

Reason two: they’re lighter

Well they are and they aren’t. Actually, it’s best not to think about it in pure weight terms, because many carbon wheels aren’t actually lighter than a set of alloy clinchers in a straight up test of the scales, which can certainly be confusing.

For example, your classic set of decent quality alloy clinchers probably come in around the 1,500-1,600g mark. That’s very similar to, say, a set of Zipp 404s, which are going to set you back around £1,500. So if it’s purely weight savings you’re after, you won’t find a great deal unless you want something carbon and shallow, like trading those 404s in for a set of 202s, for example.

Your deep section carbon wheels might not actually weigh any less than a set of standard alloy clinchers like these because they’re designed to be able to use a lot more material for a smaller weight penalty, rather than to be lighter in a like for like test

And that’s where the weight thing becomes a bit of misdirection. Think about it this way: when you buy deep section carbon wheels you’re not paying just for lower weight, you’re paying for a better weight relative to the amount of material used and, as a result, an improvement in aerodynamics.

If you made a 50mm deep wheel entirely out of aluminium alloy, it’d weigh lots. Like LOTS. Think about the first time you picked up a deep section carbon clincher. It felt light, right? But was it actually light, or light compared to what you thought it’d weigh when you looked at it? The fact that it’s a significantly more substantial wheel but doesn’t weigh lots is what makes you think that it’s light, not the fact that it’s actually any lighter than your alloy wheel, because it’s probably not.

Plus the fact that you can buy a 50mm carbon wheel that weighs the same as a box section alloy clincher means that you are, quite literally, getting a lot more for your money. Although that’ll likely be a lot more wheel for a lot more money, but there we go.

Reason three: improved aerodynamics

Carbon wheels will make you faster. Possibly. If you have the power in your legs to hold the speed at which the aerodynamic gains become significant, then definitely. Unless other variables come into play. So what I mean is that under certain circumstances, providing you’re powerful enough, carbon wheels will definitely make you faster.

But the real truth is only one thing makes you faster on the bike and that’s training. Everything else is just designed to maximise what you already have, helping you to maintain a higher speed for less effort, and carbon wheels are no different. It’s why all that fancy equipment you see the pros using is so important at their level. Pro cyclists are all so good that the differences between them are, at most, very small percentages meaning the difference between winning and losing are not particularly significant, all things considered.

They also tend to ride a bloody long way, and small savings over, say, an hour’s worth of riding end up as much bigger savings over the course of six hours.

On the other hand, if you’re a time triallist, carbon wheels are a good way to save time. Of course, the most important thing is your position, which accounts for a good 75-80 percent of drag, and the power you can put out, but I’m assuming that if you’re even a semi-serious TT rider you’ve probably got that sorted.

Time trialling is another of those areas in which the margins are so small that equipment can be very important. So if you’re a time triallist, carbon wheels should be high up on your shopping list. In fact, aero helmets, skin suits, shoe covers, tying your arms around your body for eight hours a day in an attempt to reduce the width of your shoulders and all sorts should be on your list of things to try in order to get more aero. Everything is pretty much fair game except, of course, for that particular method of improvement that rhymes with groping.

If you’re a time triallist, it’s perfectly acceptable to do all sorts of crazy things in an attempt to ride faster. One of the least crazy would be to go super deep with your wheel choice (Pic: Sirotti)

One other thing to think about is speed. Next time you look at a comparison chart for carbon wheels’ drag values check out what speed the tests were performed at. I’ll bet you it’s 50kph. I don’t know about you, but I don’t ride at 50kph. Certainly not on the flat. Maybe on the downward slope of the Champs-Elysees (from the Arc de Triomphe downwards) I could hold 50kph, but that would be balanced out by the fact that heading back up the other way I’d need an extra 45kph to reach 50.

The point is that a saving that’s significant at 50kph will be less significant at 40, and significantly less significant at 30, if you see what I mean. Another point is that these graphs frequently show just how small the difference between wheel brands are even at high speeds, meaning that for you or I there isn’t much point agonising endlessly over which wheels will provide the most significant gains. I’ve ridden probably 50-100 sets of carbon wheels over the years and, no matter how impressive, none have made my stupid legs any better at pedalling, which is a shame. Nothing could turn me from post-winter Jan Ullrich into Tour-form Jan Ullrich. Or even 10-years-into-retirement Jan Ulrich, most likely. But when someone invents a set that can, I’ll be top of the waiting list.

So…

So what’s the point of carbon wheels? Well, they’ll make you faster, providing you’re already pretty fast. And if you’re not fast, they’ll make you look cooler, which is like being fast but when you’re standing still.

If you race, and definitely if you time trial, a set of carbon wheels is a good investment and probably something which will benefit you when you compete. If you don’t then you most likely don’t need a set of carbon wheels. But since most of the funnest things in life are things we want rather than things we need, you should probably get some anyway.