Originally Posted by cyclezen

I did watch that video again and same conclusions.... Their 'real world' study is not there. as They noted , they did a lot of 'simulation', not actual measurement - from a group focused on their business, Aero Stuff. I'm all about and for science, but there is well substantiated science, and some which is not that. Let's see how the data was gathered and what it is...

Originally Posted by cyclezen

Of course you're welcome to believe whatever you think ... I could do my usual post lengthy, but not gonna completely hijack this thread...
Aero is certainly king for much of what we're talking about - and for that the human and 'position' is by far the biggest thing. So lets set aero aside as a 'given'.
I did watch that video again and same conclusions.... Their 'real world' study is not there. as They noted , they did a lot of 'simulation', not actual measurement - from a group focused on their business, Aero Stuff. I'm all about and for science, but there is well substantiated science, and some which is not that. Let's see how the data was gathered and what it is...
The Crit (as with most Brit based stuff) is on an enclosed course, no real corners - we could talk about many, maybe most real Crits, which have constant, sharp deccel & accel out of sharp corners... ****** road surfaces with drains, potholes, many possible traps...

Flywheel effect - certainly true, but so is energy loss.
Flywheel effect fades rapidly for your average rider who rides a rolling course which longer rollers which might be 4-5% grades - very common around here... In a group, you're off the back. Alone you're 10 ish seconds slower , especially at the crest, and so slower resuming a faster pace. All Additive...
Climbing longer uphillls, well I think most everyone will climb better with lighter gear... I don't know anyone in some hundreds of riders (prollu more like thousands) who has contradicted that in their approach - and certainly is true even in the higher rungs of today's sport - with adapting for the conditions.
I've done my own 'studies', and lighter comes out always faster - in some significant way.
So, why are riders spending up over $10K these days for the lightest bikes available? Certainly the aero advantages of the thousands less cost bikes are equal...
My suggestion, let each rider do their own comparison - if you have an older machine (of most any age older) and recently bought a newer machine/bike. Do some equal comparison...
decide for yourself...
Yeah, of course, the argument can be better/more choice in 'gearing', 'comfort' (maybe...).etc. But 'faster' is 'faster'... So New Bike or Old Bike - faster?
In my case
A very equal time trial of 10 miles on a light rolling course with no marked stops, equal enviromental conditions & apparent wind, aero hoods position, same kit. 3 bikes. 2009 Spec tarmac 56cm 17.6 lbs, 2023 Trek Emonda 56 cm 21.5 lbs, 1984 Colnago Master, 58cm 21.5 lbs The Tarmac by far the fastest by 26 sec. Emonda was the slowest 42 sec. behind the Tarmac. the Colnago was 26 sec behind the Tarmac (and the least aero by both position and tech). My 2014 Tarmac is always 'faster' than the 2009 (more aero and efficient), but the 2009 tarmac is my weekday ride...
Aero matters, Wheels matter, Weight matters... and, of course, the motor, most of all.
Just my view from almost 40 years of very strong involvement in competitive cycling...
Ride On
Yuri

Originally Posted by cyclezen

Climbing longer uphillls, well I think most everyone will climb better with lighter gear... I don't know anyone in some hundreds of riders (prollu more like thousands) who has contradicted that in their approach - and certainly is true even in the higher rungs of today's sport - with adapting for the conditions.

Originally Posted by PeteHski

Talking of rollers with 4-5% grade, they are my bread and butter as an 80 kg rider. 1 kg of weight is neither here nor there on that kind of terrain. We also have plenty of super steep 20%+ climbs and I do suffer on those compared to the sub 70 kg guys. Again the physics supports my observations. Weight makes a lot more difference on a 20% slope and momentum helps me on those constant rollers. Weight penalty is not such a big deal on a sub 5% slope. Especially not within the range of wheel weights anyone would be using.

Originally Posted by terrymorse

The significance of weight on a specific grade is speed dependent. The absolute speed gain from weight reduction doesn't depend much at all on speed, but the percentage gain is higher at slower speeds.

Put another way, the slower you climb, the more significant weight reduction becomes. The grade doesn't really matter that much.

Using 3 kg reduction, the speed effect on a 5% grade (kreuzotter.de with default settings):

Watts : Speed Increase
150 : +3.3%
350 : +2.1%

Originally Posted by tFUnK

I know you asked about speed but the other part of this is how much more enjoyable it will be to ride nicer tires and lighter wheels.

Originally Posted by terrymorse

The significance of weight on a specific grade is speed dependent. The absolute speed gain from weight reduction doesn't depend much at all on speed, but the percentage gain is higher at slower speeds.

Put another way, the slower you climb, the more significant weight reduction becomes. The grade doesn't really matter that much.

Using 3 kg reduction, the speed effect on a 5% grade (kreuzotter.de with default settings):

Watts : Speed Increase
150 : +3.3%
350 : +2.1%

Originally Posted by RChung

Which video did you rewatch?

How have you done your studies, and your comparisons?

Was elapsed time the thing you were measuring? How did you account for differences in wind or power?

Originally Posted by Smaug1

My road bike is a Trek Domane AL3. A lower end, aluminum-framed road bike.
Wheels are: Bontrager Paradigm, Paradigm SL or Affinity Disc,
Tires are: Bontrager R1 Hard-Case Lite, wire bead, 60 tpi, 700x32mm

I was poking around researching tire pressure, and this simple calculator says:


Here are my questions:

1. I'm guessing that those Hard-Case Lite tires are not considered supple, but I sure like the fact that I've had zero flats in over 2,000 miles of riding it. How many more flats am I going to get (all else being equal) if I get "supple, high-performance tires"?
2. How much faster will I be? I typically ride 15-17 mph, where 15 is comfortable at around a 150 heart rate and 17 is maximum effort at 175 heart rate.)
3. Someone once told me: "Get rid of those stock wheels and get something decent and it'll make a big difference in your speed." How much, do you think?

Thanks!

Originally Posted by cyclezen

the video I believe PeteHski was referring to might be this:
https://www.youtube.com/watch?v=0QDnUkUaQfk
it's anecdotal, as are my comments...

Originally Posted by RChung

...
Do you know my friend Tom? He lives in Goleta and used to be pretty active in the TT scene, and used to be fairly active in the crit racing scene. He's done a lot of testing of aero and rolling resistance on real world venues. He and I have worked together on some pretty cool bike-related tests and projects.

Fair enough. It's hard to measure the differential effects of wheel weight on acceleration without *some* equipment. It turns out that it's possible if you have some minimal equipment but the more sensors you have the easier it is. Without an accurate power meter, an accurate speed sensor, and an accurate bathroom scale it's orders of magnitude harder.

Originally Posted by terrymorse

Using either latex or TPU tubes with non-tubeless GP5K tires will produce the same rolling resistance as the tubeless-ready tires. Without the need to use liquid sealant.

Originally Posted by cyclezen

Anhalt - Blather 'bout bikes Blog... he did good stuff... also a bit younger than I.
hard to recognize anyone, in real life, when they're not in their riding kit ! LOL !

True... Not having that stuff, one does with what one has. Bike computer, HRM, whatever... course, if you can keep the variables down to one big one, humans can and do make assumptions...
and when you aren't sure (which is mostly always) , 'lighter' has mostly always been a safe bet... LOL!
anyway, it's great that we do get some great science for our thing, even though it's often poorly funded...
Ride On
Yuri

Originally Posted by cyclezen

the video I believe PeteHski was referring to might be this:
https://www.youtube.com/watch?v=0QDnUkUaQfk
it's anecdotal, as are my comments...

Originally Posted by Shadco

Just in case you haven’t come to a conclusion that nicer wheels, upgraded tires, and improved air retention system will make a difference it will.

Conti GP5k’s aren’t the only choice in the tire dept. I went from tubeless to tpu’s on these tapeless rims and Turbo Cotton Hell of the Norths in 28c. The tires ride great and are much easier to deal with in the event they need to be mounted or dismounted easily done by hand compared to the wrestling match I had with the Schwalbe tubeless Pro Ones and from what I can see in the shop even the str gp5ks are a *****.

I ditched the Pro ones because because that bike wasn’t getting enough time compared to my other bike at the time and maintaining sealant more often then riding just didn’t make sense. My other ride is on Pirelli P Zero clinchers and tpu’s from the get go and for me I just preferred this combo but to each it’s own.




.

Originally Posted by PeteHski

I was actually referring to the SwissSide analysis, which included a detailed report which I can no longer find (probably because it referred to a competing brand’s lightweight wheel). They modelled aero, rolling resistance, weight and rotational inertia and their relative effects on performance over various road course profiles. From a physics and modelling perspective, mass and inertia are very easy to deal with, so I have no reason to question their model in this regard. If you were being cynical you could question their aero modelling, but it wouldn’t change the individual mass and inertia contributions to the model. The latter in particular was very small which fits in with my own professional experience of vehicle modelling. It’s a third order parameter in most models.

Originally Posted by RChung

Yeah. I think Ballard does pretty good analysis, though I was surprised that, in that video, he said that he was surprised about the result. I thought that was well-understood even if not always well-known. We'd done experimental tests of wheels with different rotational inertia on the track (for team pursuit, where accelerations/decelerations happen all the time). It turns out that humans on bikes don't accelerate very quickly (in an absolute sense) even during a track pursuit -- on the road, or up a hill, or even in a crit, our accelerations are even lower. So the mass of the wheel matters but the contribution to power demanded is *almost* *entirely* described by the additional mass term, and not the moment of inertia term. That's why in my estimation equation for drag, I usually leave it out. There's a new paper in Sports Engineering that models the power demands of track cycling. Their model looked at instantaneous power demand around a track, when your wheels are accelerating as they do in the turns or decelerating as you exit the turn, but I look at net power demand (where you have to look at both the acceleration and deceleration, net) across a lap. My recollection is that, while they do look at a rotational inertia term, its contribution to total power demand when you integrate across a lap is essentially zero.

Light wheels and good tires feel nice, though.

Originally Posted by PeteHski

Sealant is actually optional with some tubeless tyres. I ran my mountain bikes for years tubeless, without any sealant. Of course you then get flats just like you do with tubed tyres, but at least you can repair them in situ much faster with a plug kit. Adding sealant just makes flats a lot less likely and you can still plug any larger holes - which doesn’t work with sealant filled tubes.

Some tyres do require sealant to seal the sidewalls if they are porous, but a lot don’t. When I’m being lazy (often after a winter break) I will often ride my bikes with dried out sealant and they work just fine. Obviously you lose the flat protection, which is the primary advantage of adding sealant. The only reason why sealant is not so popular in tubed tyres is because it is much less effective at sealing a blown out thin tube vs a punctured tyre.

Sealant only really gets potentially messy if you are forced into fitting a tube at the roadside, which I have never had to do with any tubeless setup in 20 years.

Originally Posted by RChung

Yeah. I think Ballard does pretty good analysis, though I was surprised that, in that video, he said that he was surprised about the result. I thought that was well-understood even if not always well-known. We'd done experimental tests of wheels with different rotational inertia on the track (for team pursuit, where accelerations/decelerations happen all the time). It turns out that humans on bikes don't accelerate very quickly (in an absolute sense) even during a track pursuit -- on the road, or up a hill, or even in a crit, our accelerations are even lower. So the mass of the wheel matters but the contribution to power demanded is *almost* *entirely* described by the additional mass term, and not the moment of inertia term. That's why in my estimation equation for drag, I usually leave it out. There's a new paper in Sports Engineering that models the power demands of track cycling. Their model looked at instantaneous power demand around a track, when your wheels are accelerating as they do in the turns or decelerating as you exit the turn, but I look at net power demand (where you have to look at both the acceleration and deceleration, net) across a lap. My recollection is that, while they do look at a rotational inertia term, its contribution to total power demand when you integrate across a lap is essentially zero.

Light wheels and good tires feel nice, though.

[Edited to add:] In 2005, Ondrej Sosenka broke Boardman's "Merckx-style" hour record using a "heavy wheel" that reportedly weighed something like 3kg so the rotational inertia would be high. I'm not sure it worked as he thought it might but he broke and held the record, so there's that.

Originally Posted by PromptCritical

One thing to keep in mind is that heavier factory wheels aren’t just heavier, they are probably not as stiff as a good wheelset. Back in the day, our coach suggested wiring the spokes together at the cross, and it made a noticeable difference in feel. Of course, back then our sundials weren’t precise enough to measure the difference.

Originally Posted by cyclezen

Ok, So not disputing any of what you say is found in accepted 'testing'.
I'd like to see - to be convinced - a more 'real world' test situation... it will have a load of variables, which will preclude any real determination of which elements have the greatest effect - however the ultimate results will provide a more 'real world' conclusion of wheel results for 'lighter wheels are better?"
So, 1 rider of say middling mass - 165-170 lbs rider weight, using one bike, using 2 different wheelsets. One wheelset in the 2200g + wheelset weight with corresponding similar level tires, 2nd set = 1400g ish wheelset with accepted top level tires (GP 5000s or similar?).
running start, in-saddle Acceleration test from 15 mph to 27 mph Why 15 to 27? Because if you're in a crit with corners, and mid or rear pack with a big field, doing that 4x for about 1 mile distance, ongoing for 50+ miles of race pace riding, is common...
What are we measuring? Power / time & Speed / time.
Time on the x axis, and 2 curves - one is the power curve and the other the speed curve. Both curves plotted on the Y on the same chart. Prolly doesn't have to exceed a 15 sec accel segment.
does NOT have to be done in a turn/corner, straight line acceleration is fine and removes technique and cornering skills variables. But same rider, same bike, 2 wheelsets.
Will there be any possible determination of any one of the variables of wheel, tire, weight, aero or crr ? no, but we might/should get a real determination of the overall effect of 'lighter/faster'.
Why Crit 'cornering' simulation? because there will likely be a noticeable difference, and even a solo everyday rider will be able to comprehend the results and make decisions for themselves how much it means to them. I'm willing to wager a case of good bier that there will be a noticeable difference
Ride On
Yuri
EDIT: to create an easily understood chart, use the same color for each curve type - say Bright Blue for Speed and Orange for Power. And use Solid and Dash curves to designate the differing wheelsets (of the color/curve type). So Power curves for 2 wheelsets would both be Orange, one solid, one dashed... etc.
But no 'simulations', actual data/results

Originally Posted by cyclezen

Ok, So not disputing any of what you say is found in accepted 'testing'.
I'd like to see - to be convinced - a more 'real world' test situation... it will have a load of variables, which will preclude any real determination of which elements have the greatest effect - however the ultimate results will provide a more 'real world' conclusion of wheel results for 'lighter wheels are better?"
So, 1 rider of say middling mass - 165-170 lbs rider weight, using one bike, using 2 different wheelsets. One wheelset in the 2200g + wheelset weight with corresponding similar level tires, 2nd set = 1400g ish wheelset with accepted top level tires (GP 5000s or similar?).
running start, in-saddle Acceleration test from 15 mph to 27 mph Why 15 to 27? Because if you're in a crit with corners, and mid or rear pack with a big field, doing that 4x for about 1 mile distance, ongoing for 50+ miles of race pace riding, is common...
What are we measuring? Power / time & Speed / time.
Time on the x axis, and 2 curves - one is the power curve and the other the speed curve. Both curves plotted on the Y on the same chart. Prolly doesn't have to exceed a 15 sec accel segment.
does NOT have to be done in a turn/corner, straight line acceleration is fine and removes technique and cornering skills variables. But same rider, same bike, 2 wheelsets.
Will there be any possible determination of any one of the variables of wheel, tire, weight, aero or crr ? no, but we might/should get a real determination of the overall effect of 'lighter/faster'.
Why Crit 'cornering' simulation? because there will likely be a noticeable difference, and even a solo everyday rider will be able to comprehend the results and make decisions for themselves how much it means to them. I'm willing to wager a case of good bier that there will be a noticeable difference
Ride On
Yuri
EDIT: to create an easily understood chart, use the same color for each curve type - say Bright Blue for Speed and Orange for Power. And use Solid and Dash curves to designate the differing wheelsets (of the color/curve type). So Power curves for 2 wheelsets would both be Orange, one solid, one dashed... etc.
But no 'simulations', actual data/results