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May 19, 2014 at 10:29 am #21473
PaulBox
Hi, sorry if this is a really stupid question, but I’m currently thinking about buying some new wheels for my road bike and can’t find the answer elsewhere.
I’m considering a set of Pro Lite Bracciano A42’s because they are supposedly strong (I’m a big lump), have the upside of being aero and look quite nice. Obviously not a sexy as their carbon equivalents, but due to being heavy I don’t want to risk getting carbon wheels at this point.
What’s putting me off is that I keep seeing references to aero section wheels not being good on climbs and in windy conditions. The windy conditions bit is self explanatory, but I can’t see why they would be detrimental to climbing. Being a big lump I certainly don’t need any other hindrances on climbs…
Thanks in advance for help/advice, Paul.
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matthewn5
I don’t want to get personal,
I don’t want to get personal, just to put it all in perspective regarding marginal gains. At 6′ 4″ (193.04cm) you have a BMI of 28.2, which is in the ‘overweight’ range:http://www.nhlbi.nih.gov/guidelines/obesity/BMI/bmi-m.htm
The maximum BMI in the ‘healthy range’ is 25, so your maximum healthy weight would be 93kg.
To become competitive you probably need a BMI of about 22.7 (the average BMI of nine cycle racing champions including Merckx, Altig and Gimondi, see http://www.etape.org.uk/BMI1.htm) which means a weight of 84.5kg…
So just enjoy riding your bike! Don’t worry about your weight, or your bike’s weight, unless you want to race.
bashthebox
Read Michael Hutchinson’s
Read Michael Hutchinson’s book, Faster, and specifically the section on aerodynamics and tech. He explains really well all the aero tech.
The biggest point you can grasp is that wind resistance increases with the square of velocity – i.e. the wind resistance increases exponentially the faster you go.
Apparently this is complicated at cycling speeds because we go roughly at the threshold speed for turbulent and laminar flow – so it’s really hard to design components to have good aero properties in both.
Also, our big lumpy bodies are rubbish in terms of aero profile, and the frontal area of the bike compared to the frontal area of us is tiny.
The lesson being – work on your flexibility so you can ride with your back as flat as possible. That’ll give you fairly big gains. After that, sort out baggy and flappy clothing. Then get an aero helmet. Finally, upgrading first wheels and then frame will all give you an extra half watt or so.
Basically, the bike bling makes no noticeable difference unless you’re TTing on your own against the clock… and even then, a few seconds per km.
So just buy the wheels you want rather than agonising over it. Remember half the reason pro teams ride all the bling is so the sponsors can advertise and sell the bling. If it made much difference, they’d all be on very similar tech all the time (see aero helmets for sprint finishes).Gordy748 wrote:Regarding
Gordy748 wrote:Regarding wheels specifically, you can get down to 1,100 grams for low profile alloy clinchers for about 700 quid, but these would be for races only. Whether these would be faster than heavier, deeper wheels is dependent on a number of factors…I don’t think that wheels that light would be a good idea given my weight. I’m looking at Zipp 30’s at the moment, forgetting the aero section now as I want something that I can use every day, i.e. not worrying about wind etc. (I don’t race or anything). They seem pretty reasonable value for a big brand factory wheelset. Do you think they would do a job for me?
Paul.
timtak wrote:The best way to
timtak wrote:The best way to climb faster is to loose weight. The best way to loose weight is to get on your bike. One good way to motivate yourself to get on your bike is to get one with a lot of bling including aero wheels.I 100% agree with the principal that enjoying your bike makes it easier to get out on it, but I don’t find that it helps me to lose much weight, probably due to the cake stops etc…
When I say I’m a big lump, yes I am overweight, but I’m also 6’4″ so even at my fighting weight I’m still 105kg. I also agree that losing a bit of weight is the best way of improving climbing performance, I certainly notice a huge difference when I’ve knocked off a couple of lbs.
timtak
The best way to climb faster
The best way to climb faster is to loose weight. The best way to loose weight is to get on your bike. One good way to motivate yourself to get on your bike is to get one with a lot of bling including aero wheels.Gordy748
Having just built a pair of
Having just built a pair of race wheels for a hill climb specialist…The best way to climb faster is to lose weight. Unless you’re an elite athlete, the chances are you can shift at least 5 – 10 pounds, and many could lose 20. Effectively this is the same as having a bike that weighs nothing or even floats. Plus you’ll look buffer than David Hasselhoff in Baywatch. Cool, huh?
The next fastest way is position. Work on staying on the hoods or the drops if you can. Using the hoods offers a more aerodynamic position. After that, focus on tighter clothing; you’d be very surpised how much drag is created by a ballooning jacket that’s too large, even at 15 mph. Getting an aero road helmet like a Giro shield is arguably one of the cheapest ways of shaving time.
Regarding wheels specifically, you can get down to 1,100 grams for low profile alloy clinchers for about 700 quid, but these would be for races only. Whether these would be faster than heavier, deeper wheels is dependent on a number of factors, such as:
1) gradient. The steeper the climb the more important weight (or lack of it) is. The lesser the gradient the more important aerodynamics is.
2) wind. Some places are a lot more exposed than others so deeper wheels are more likely to get pushed around.
3) direction. Deep rims work the same way as aircraft wings. Contrary to the above they are quicker on flats in a direct headwind, but as the angle of crosswind increases so does the likelihood they will stall. You won’t fall out of the sky but the deep rim will cause more turbulence than benefit so will actually slow you down as well as cause instability.
4) road surface. Deep rims are stronger but more rigid. If your hills tend to be on poor tarmac then you’re better off on shallower, more flexible rims.That said, what goes up must come down and go across flats. Unless you live somewhere where there is a gale every other day then deep rims will be overall faster than shallow rims.
matthewn5
British Cycling say the
British Cycling say the greatest climbing improvement you can make is to lose weight… losing a couple of kg will make a big difference for next to nowt, whereas as taking 2kg off a typical bike will cost you a couple of grand, at least.Cruel but fair:
“Bodyweight
It’s no coincidence that the most explosive and best climbers tend to be rake thin. If you’re carrying a few excess pounds then, some sensible weight loss, is one way to guarantee better climbing performance. Don’t try to crash diet though as you’ll compromise your training and, if you lose weight too quickly, you could end up losing muscle mass, power and end up climbing worse. Nigel Mitchell, Great Britain Cycling Team Nutritionist and Insight Zone expert, gives advice about safe, sensible and effective weight loss during training in our Power to Weight Ratio feature.”Remember that Wiggo had to lose 10% of his weight to be competitive in the TdF.
They go on to say:
“Bike Weight
Once you’ve trimmed down your waistline, shedding some weight off your bike is a fun but expensive way to improve your climbing performance. Before you start obsessing about titanium bottle cage bolts though, remember that the most significant performance gains are to be had by reducing rotating weight. Upgrading your wheels is usually the bang for your buck most effective way to buy some uphill speed. Additionally lower spec and heavy wheels, relative to the rest of the bike, are a common way for manufacturers to produce attractive looking packages, so it’s not unlikely that your wheels aren’t doing your bike justice.”All at http://www.britishcycling.org.uk/insightzone/techniques/climbing/article/izn20130115-Road-Climbing-Strong-0 (may need to log in).
colinth
I’m heavy, 95kgs and switched
I’m heavy, 95kgs and switched to 52mm aero rims from climbing wheels. The aero wheels are roughly 300 grams heavier and I’m faster over rolling / moderate hills. I haven’t done any major climbs on them, but overall my average speed over a rolling 30 mile test loop I do which has a couple of half mile climbs at 5% is 1.5mph faster.If I was doing some serious climbing in the Alps etc I’d probably switch back to climbing wheels, but that’d be mainly due to them being a bit more stable to side winds on fast alpine descents
To be fair, I’m not really
To be fair, I’m not really analysing anything, I only asked why they are not so good for climbing… 😉glynr36
Wesselwookie wrote:edster99
Wesselwookie wrote:edster99 wrote:Strava tells a story of an average speed difference of about 2.6kph between winter bike (blue ribble / 11kg / 36 spoke low profile rims) and summer bike (carbon Ridley /8.2kg / variety inc deep section carbons). Right now, that is a comparison of almost exactly 3000km on each so quite a good comparison. So – something is making a difference, and its not just the legs!That may be true but unless you are using both bikes in exactly the same conditions it may simply be you travel slower in the winter than the summer.
My winter average is 1 to 2 mph slower.Colder air is denser…
dangoscomb
I started riding 50mm carbon
I started riding 50mm carbon clinchers on my road bike (though i bought them for windy days on the TT bike in Lanzarote). I can’t say i’ve noticed the winds too much in the UK, but then on the TT bike I usually ride a disc and an 808 so may be i’m just a bit more used to it?I love them. They look great, sound great, are lighter than my previous Mavic KSYRIUM Elites.
Buy what makes you happy!
BBB
To the OP.
You may be
To the OP.
You may be over-analysing it.
It will make **** all difference to your average speed, acceleration and enjoyment of riding whichever half decent wheels you’re going to choose, especially as in your own words you are a “big lump”.
Pick the ones that look good.edster99
Wesselwookie wrote:edster99
Wesselwookie wrote:edster99 wrote:Strava tells a story of an average speed difference of about 2.6kph between winter bike (blue ribble / 11kg / 36 spoke low profile rims) and summer bike (carbon Ridley /8.2kg / variety inc deep section carbons). Right now, that is a comparison of almost exactly 3000km on each so quite a good comparison. So – something is making a difference, and its not just the legs!That may be true but unless you are using both bikes in exactly the same conditions it may simply be you travel slower in the winter than the summer.
My winter average is 1 to 2 mph slower.Yeah maybe. Some of it (as has been noted) is due to the weather and dancing carefully round wet corners. But the other thing I notice is how much more effort it takes to drive the blue battleship round the corners and accelerate out. thats at least partly due to the lighter weight of the wheels. If I’m getting back up to speed more quickly, then that will help my average.
Wookie
edster99 wrote:Strava tells a
edster99 wrote:Strava tells a story of an average speed difference of about 2.6kph between winter bike (blue ribble / 11kg / 36 spoke low profile rims) and summer bike (carbon Ridley /8.2kg / variety inc deep section carbons). Right now, that is a comparison of almost exactly 3000km on each so quite a good comparison. So – something is making a difference, and its not just the legs!That may be true but unless you are using both bikes in exactly the same conditions it may simply be you travel slower in the winter than the summer.
My winter average is 1 to 2 mph slower.
Simon E
700c wrote:The idea that
700c wrote: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.Really? Many, many people are buying bike kit (often prefixed with the word “carbon” or “lightweight”) simply because they can. For lots of cyclists training is not a priority, while having the ‘right’ gear most certainly is.
If you’re happy with your wheels that’s great. I really don’t have a problem with it, and you don’t need to justify yourself. I am merely trying to explain that the marketing guff and the real world can be some distance apart. Wind tunnel data is certainly not irrelevant, it’s how people test aero performance.
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