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-   -   Largest Misconception in cycling- wheel weight matters! (https://www.bikeforums.net/showthread.php?t=987180)

frisbie17 12-28-14 05:30 AM

Largest Misconception in cycling- wheel weight matters!
 
Why do so many people think Aero wheel are worse for climbing?

I understand carrying a little extra weight seems like a big deal. But the Aero properties of wheels many times more important then the small changes in wheel weight. Mathematically speaking. Even with the weight away from the hub towards the rim.

See the link below for article and the math behind this misconception.

Wheel Performance

Whats your thoughts?

frisbie17 12-28-14 05:36 AM

Another study with same results.

Flo Cycling Blog: FLO Cycling - The Great Debate - Aero vs. Weight *Edited

frisbie17 12-28-14 05:39 AM

And another. Why Wheel Aerodynamics Can Outweigh Wheel Weight and Inertia - Slowtwitch.com

rpenmanparker 12-28-14 06:41 AM

Lighter wheels feel better and are more fun to ride than heavier wheels. Ride aero if you like, but also just remember you will like your wheels best if they are as light as you can afford while not sacrificing other characteristics you value. Lighter aero wheels will give a more attractive ride than heavier ones. As someone who doesn't care about the aero advantage for my type of riding, lightest, non-aero wheels are for me. That doesn't nullify the truth of anything you said, OP.

datlas 12-28-14 06:59 AM

I can't argue with physics. But if you think about how many races and even spirited club ride are ridden, there are periodic accelerations where you either snap with the group or you get dropped (and lose the draft which matters much more than wheels).

I don't think the analysis factors in frequent acceleration where light weight is more of a factor.

FrenchFit 12-28-14 07:18 AM


Originally Posted by frisbie17 (Post 17420389)
Why do so many people think Aero wheel are worse for climbing?

I understand carrying a little extra weight seems like a big deal. But the Aero properties of wheels many times more important then the small changes in wheel weight. Mathematically speaking. Even with the weight away from the hub towards the rim.

See the link below for article and the math behind this misconception.

Wheel Performance

Whats your thoughts?

The faulty assumption in your argument, and those "studies", is the rider is strong enough / light enough / fast enough to take advantage of the aero properties of those wheelsets. If you are taking about the rec rider who isn't hammering, I suspect weight trumps aero pretty much every time.

I recall a long climb I did where I was working very hard just to maintain about 12 mph. Two guys in full racing kits passed me like I was standing still, I'd say 20+ mph for sure - they obviously were on a a training ride - I was simply surviving. A little extra weight was a big deal for me, not so much for them.

frisbie17 12-28-14 07:38 AM

Overall weight of you and the bike does matter. The small variances in a few pounds in the wheels is far outweighted by drag on the wheels. Even at slow speeds.

frisbie17 12-28-14 07:41 AM

Also note the speed of you moving on the bike the rotating speed of the wheels is not the same. Do the math.

gsa103 12-28-14 08:07 AM

Yes, if you live in the flats or race then aero matters. At 8mph, aero is meaningless. Lightweight wheels also feel better standing.

frisbie17 12-28-14 08:10 AM

Review the first article I posted on the inertia facts.

carpediemracing 12-28-14 08:13 AM


Originally Posted by datlas (Post 17420455)
I can't argue with physics. But if you think about how many races and even spirited club ride are ridden, there are periodic accelerations where you either snap with the group or you get dropped (and lose the draft which matters much more than wheels).

I don't think the analysis factors in frequent acceleration where light weight is more of a factor.

+1

I should add that frequent accelerations are a huge factor when drafting.

I totally agree that aero wheels are overall faster than non-aero when riding solo - the numbers I've seen for my own rides over the last 4 years seem to support that. I generally ride on a flatter route so ideal for aero wheels.

However in a situation where drafting is present and the rider knows how to take advantage of it (group ride, race), the drafting aspect is significantly more important than wheel aerodynamics. It's most important to have the draft, a distant second or third or whatever to have aero wheels. In these situations having equipment that enables a rider to draft more effectively is key. This might include a shorter front end (motorpace bicycles use small wheels and backward/negative-rake forks to bring the rider closer to the moto), rider position (Specialized found a significant decrease in drag while drafting in the drops compared to the hoods, for the n=1 sample they did), distance to rider in front (closer is better although the benefits are measurable even when relatively far away), number of riders in front of you (more riders = more draft, ideally with at least one rider drafting behind you), and even self drafting (on shorter tracks a rider doing laps will set up his own wind current and end up "drafting himself").

Trsnrtr 12-28-14 08:55 AM


Originally Posted by gsa103 (Post 17420520)
Yes, if you live in the flats or race then aero matters. At 8mph, aero is meaningless. Lightweight wheels also feel better standing.

Unless that's 8 mph into a 30 mph headwind. People seem to forget that air resistance is not always generated by the rider going fast. For example, a wind tunnel. ;)

Trsnrtr 12-28-14 08:58 AM

I recently bought a new Giant Propel. I could afford the Di2 shifting or the 50mm carbon aero wheels but not both. I chose the wheels over electronics despite having an electronic shifting bike would mean using lighter wheels and an overall lighter weight.

frisbie17 12-28-14 09:07 AM

“climbing wheels”- If you want to know if a set of chi-chi “climbing” wheels is right for you, ask yourself these questions: Is the joy of a smooth riding bike more important than a competitive edge? If you do compete, do you spend the majority of the race going uphill at less than 17mph? Does your bike spend a significant amount of time on a gram scale? If you answered “yes” to all of these questions, then go out and buy those climbing wheels now! The facts are that a real aerodynamic advantage will beat a weight advantage at any speed above a crawl but a deep-profile aero wheel is going to ride harsher. Climbing wheels are also for the vanity of people who need the lightest bike their money can buy, and personally I am so over gram-counters. Yesterday at work, some tosser interrogated me about the weights of the inner tubes we had in stock. You can go ahead with your delusions that saving 15 grams on an inner tube would have you flying like Pantani on the cols, but buy yourself a gram scale and leave me out of it. (Besides, Pantaniwould have never gotten rid of a few grams.)
Is light weight a good thing? Yes. Is it better than aerodynamics? Usually not. Do I have to choose between weight and aerodynamics? With the latest carbon deep-profile wheels on the market, no…you can have both…you just won’t have money left to buy food or pay rent.

WhyFi 12-28-14 09:12 AM

Thank you for bringing this to our attention - I don't think that we've touched on this subject before!

xscottypx 12-28-14 09:44 AM

i rode one of my usual rides which is fairly flat with maybe a 200' change in elevation over a long stretch. lots of wind. i rode my newer wheels, which are around 700 grams lighter if not more and bladed spokes. maybe i was feeling good IDK but i was cutting through gusty winds a bit easier, made some great times. my wheels are not aero at all. i could feel the bike being easier to push. or it was all in my head.

gregf83 12-28-14 09:47 AM


Originally Posted by carpediemracing (Post 17420530)
+1

I should add that frequent accelerations are a huge factor when drafting.

I totally agree that aero wheels are overall faster than non-aero when riding solo - the numbers I've seen for my own rides over the last 4 years seem to support that. I generally ride on a flatter route so ideal for aero wheels.

However in a situation where drafting is present and the rider knows how to take advantage of it (group ride, race), the drafting aspect is significantly more important than wheel aerodynamics. It's most important to have the draft, a distant second or third or whatever to have aero wheels. In these situations having equipment that enables a rider to draft more effectively is key. This might include a shorter front end (motorpace bicycles use small wheels and backward/negative-rake forks to bring the rider closer to the moto), rider position (Specialized found a significant decrease in drag while drafting in the drops compared to the hoods, for the n=1 sample they did), distance to rider in front (closer is better although the benefits are measurable even when relatively far away), number of riders in front of you (more riders = more draft, ideally with at least one rider drafting behind you), and even self drafting (on shorter tracks a rider doing laps will set up his own wind current and end up "drafting himself").

Agree that staying in the draft is #1 and given your avg power numbers in a race I think you are the master at it. However, being in the draft and having aero wheels is not an either/or scenario. It's best to be in the draft with aero wheels. Even in the draft aero drag is still the most significant consumer of power and having aero wheels will lower that.

Over the course of a race you'll save far more energy with aero wheels than you will with lighter wheels. The energy costs of repeatedly accelerating a few hundred extra grams is surprisingly low relative to the savings from aero equipment. Ideally, it's best to have light aero wheels but if the alternative is heavy aero wheels vs light non-aero wheels, the aero ones will win every time in anything other than a steep hill climb.

wphamilton 12-28-14 09:47 AM

I like these wheel-weight threads, because the numbers say one thing while the riders say another! Something is missing in the physical mechanics, something more than "it feels better".

What we really need is an objective examination of the rider, on lighter and heavier wheels. It occurred to me that the rotational inertia impacts the steering, which in turn impacts how easily the rider holds a line or even stays upright. I don't mean holding the bike up due to the gyroscopic wheel - that force isn't nearly large enough. But it impedes turning the wheel, all of those tiny constant corrections we do without even thinking about it. These corrections will be slower with the heavier wheel, perhaps with a lower frequency and greater amplitude. Perhaps, and I'm just spit-balling, it can lead to either more serpentine motion or more large body movements to correct the balance. In either case it could lead to greater energy expended, that isn't captured by the basic equations of motion used in these calculations.

gregf83 12-28-14 09:48 AM


Originally Posted by xscottypx (Post 17420660)
i rode one of my usual rides ... my wheels are not aero at all. i could feel the bike being easier to push. or it was all in my head.

correct.

cruiserhead 12-28-14 09:50 AM

If you believe the studies, than people should be killin it riding Aerospokes.
1200g each and 4 aero spokes.
Fred Flintstone was on to something

I'll let you know when I win the Tour de France.
http://steelturman.typepad.com/photo...ne_bicycle.png

BoSoxYacht 12-28-14 10:04 AM


Originally Posted by wphamilton (Post 17420669)
I like these wheel-weight threads, because the numbers say one thing while the riders say another! Something is missing in the physical mechanics, something more than "it feels better".

What we really need is an objective examination of the rider, on lighter and heavier wheels. It occurred to me that the rotational inertia impacts the steering, which in turn impacts how easily the rider holds a line or even stays upright. I don't mean holding the bike up due to the gyroscopic wheel - that force isn't nearly large enough. But it impedes turning the wheel, all of those tiny constant corrections we do without even thinking about it. These corrections will be slower with the heavier wheel, perhaps with a lower frequency and greater amplitude. Perhaps, and I'm just spit-balling, it can lead to either more serpentine motion or more large body movements to correct the balance. In either case it could lead to greater energy expended, that isn't captured by the basic equations of motion used in these calculations.

maybe I'm wrong, but when riding on rough pavement(think of a gravel road, but it's actually paved), my heavier wheelset feels smoother. I was thinking the gyroscopic effect helped keep the bike more on line.

wphamilton 12-28-14 10:13 AM


Originally Posted by BoSoxYacht (Post 17420706)
maybe I'm wrong, but when riding on rough pavement(think of a gravel road, but it's actually paved), my heavier wheelset feels smoother. I was thinking the gyroscopic effect helped keep the bike more on line.

Maybe fewer, slower corrections are just the thing for rough pavement. This is a clue that at least it does impact the handling in some conditions, even though your example differs from what I had in mind.

frisbie17 12-28-14 10:24 AM

Every article I have read and found with data from tests show that Aero even at low speeds is much more important then weight. Please somebody post something scientific that shows different. The whole spins up easier does not pass the mustard. As the majority of acceleration is overall weight and drag not just wheel weight.

I can buy the argument that a lighter wheels feels better to a person or any other preference due to their opinion or feel. Just not that Aero is less important then weight when it is mathematically proven different in most if not all tests.

BoSoxYacht 12-28-14 10:29 AM


Originally Posted by wphamilton (Post 17420717)
Maybe fewer, slower corrections are just the thing for rough pavement. This is a clue that at least it does impact the handling in some conditions, even though your example differs from what I had in mind.

I notice that most of the time when I'm riding, my bike feels better handling when using my lightweight wheelset, and a little sluggish handling with my heavier aero wheels. Only over the rough pavement does it feel better with the heavy ones.

BoSoxYacht 12-28-14 10:33 AM


Originally Posted by frisbie17 (Post 17420737)
Every article I have read and found with data from tests show that Aero even at low speeds is much more important then weight. Please somebody post something scientific that shows different. The whole spins up easier does not pas mustard. As the majority of acceleration is overall weight and drag not just wheel weight.

I can buy the argument that a lighter wheels feels better to a person or any other preference due to their opinion or feel. Just not that Aero is less important then weight when it is mathematically proven different in most if not all tests.

none of the testing you have mentioned talks about how aero/heavier wheels affect handling.


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