Originally Posted by 3alarmer

Were your statement true in the case of bicycle wheels, someone at R+D would be working on the steel, deep dish, aero rim even as I type this. They would be very fast downhill.

Originally Posted by 3alarmer

Bicycling does not happen under laboratory conditions, there are uphills, and wind, and **** like that, which mean that on any given 112 mile ride, you will be compelled to bring those wheels up to speed more than a few times.

Originally Posted by Lombard

This is very misleading. The rolling weight argument is way overblown. Sure, less rolling weight will make you accelerate faster and therefore make you feel faster. However, once up to speed, weight is weight.

Originally Posted by Koyote

This.

For road riding on flat terrain, weight is no big deal. That's why I'm still happily riding 32h/3x alloy rims on my road bike. But I do a fair bit of gravel racing, which involves hills, changing terrain, etc -- i.e., LOTS of yo-yo'ing in the speed. So, when buying new race wheels for my gravel bike, I chose a 1410g wheelset with cf rims and lower spoke count.

Originally Posted by 3alarmer

...the problem in me discussing this with most of the people here, is that they have never ridden on steel rims. The changes have been incremental, and a lot of the stuff you've read online about it has been comparisons between wheel sets with little tiny differences in weight. Thus it's not unusual at all for me to have people saying stuff like this to me.

Like I don't understand the physics or the numbers. I try not to personalize it, but it's very hurtful. Bicycling does not happen under laboratory conditions, there are uphills, and wind, and **** like that, which mean that on any given 112 mile ride, you will be compelled to bring those wheels up to speed more than a few times. Were your statement true in the case of bicycle wheels, someone at R+D would be working on the steel, deep dish, aero rim even as I type this. They would be very fast downhill.

Originally Posted by Eric F

What wheels did you get? Somewhere on my list of future upgrades for my gravel bike is new wheels.

Originally Posted by 3alarmer

...while the forces we are discussing certainly are less than aerodynamics (probably by a factor of ten), that does not mean this statement you have just made is correct. Here is a long blog post about the subject. I'm not prepared or willing to argue it with you, because you give the impression that you are another true believer. I don't argue on Bike Forms with true believers, but I occasionally throw them a link. This is the same stuff that people argue endlessly, in road, about how wider tires are actually faster (even if they are heavier and run at lower pressures), and I realize that discussion of such topics simply wastes both your time and mine, You have misinterpreted some of the results coming out of the improvements with modern wheel aerodynamics as invalidating the established rotational weight dynamics, simply because they are a greater order of magnituce.

Fortunately, upgrading the wheels on an older bike to make it go faster is still OK advice, because the wheel upgrade will include both aspects. It's not a choice between one or the other.

Originally Posted by Koyote

These. They should be on the way soon, so no feedback for you.

I'm a bit old school, so when I got my gravel race bike, I had the shop build some alloy-rimmed 32h wheels for it, and they've been flawless. But I've thrashed them enough that I decided to get some dedicated race wheels. Still old school enough that I wanted hooked rims, though -- otherwise there are a bunch of great options for hookless rims.

Originally Posted by 3alarmer

...the problem in me discussing this with most of the people here, is that they have never ridden on steel rims. The changes have been incremental, and a lot of the stuff you've read online about it has been comparisons between wheel sets with little tiny differences in weight. Thus it's not unusual at all for me to have people saying stuff like this to me.

Like I don't understand the physics or the numbers. I try not to personalize it, but it's very hurtful. Bicycling does not happen under laboratory conditions, there are uphills, and wind, and **** like that, which mean that on any given 112 mile ride, you will be compelled to bring those wheels up to speed more than a few times. Were your statement true in the case of bicycle wheels, someone at R+D would be working on the steel, deep dish, aero rim even as I type this. They would be very fast downhill.

Originally Posted by Lombard

This is laughable, really. Sounds like you enjoy playing the victim. There is a much bigger weight savings going from an old set of wheels with steel rims to modern alloy wheels in the 1600-1800g range than going from modern alloy wheels in the1600-1800g range to 1400g carbon wheels. I call false equivalency.

Originally Posted by Lombard

And wheels are not pizza. They are deep section rims, not deep dish rims.

Originally Posted by Lombard

Where are you coming up with this "true believers" stuff? My point was that reducing rotating weight only helps you on acceleration. Once up to speed, it doesn't matter where you reduce weight - whether it's the rims, the bike, the group set or the engine (rider).

....

Originally Posted by tomato coupe

Did you actually read the blog that you linked? Some excerpts:

Originally Posted by tomato coupe

It doesn't matter what the wheels are made of. It takes very little extra power to keep a heavier set of wheels rotating at a given speed than a lighter set of wheels. That's physics.

Originally Posted by tomato coupe

Originally Posted by 3alarmer

...of course I read it. That is why I've been telling you stuff like, it really does matter how much your rims and tires weigh.
Aerodynamics is a greater improvement by a factor of maybe ten. But that doesn't mean all the stuff about rotational mass goes away.

Originally Posted by 3alarmer

This statement was in response to a statement that it doesn't matter what wheels are made from. Once you get them up to speed, it's all the same.

Originally Posted by 3alarmer

I don't know where you learned about this stuff, but you can call false equivalence, unfair advantage, or your mom.........

Originally Posted by 3alarmer

...says the guy who uses rolling weight to describe rotational mass. Go away, man.

Originally Posted by 3alarmer

...of course I read it. That is why I've been telling you stuff like, it really does matter how much your rims and tires weigh.
Aerodynamics is a greater improvement by a factor of maybe ten. But that doesn't mean all the stuff about rotational mass goes away.

I'm now faced with you and this Lombard guy (who probably isn't really a resident of Lombardy anyway) going back and forth, telling me that my proposing we go back to making wheels from steel is ridiculous, when that's the very reason I brought it up. It's been so long since you've had to think about rotational mass as something to consider, because this change in materials and weight (both in wheel rims and in tires) has been accomplished to the point where, in your world view, you can make ridiculous statements like:

and not expect any pushback. Because you have a limited experience with bicycle wheels, which has occurred in the modern era when changes were much less drastic. Then I simply state the obvious, that at the extreme, your claim would mean steel rims are fine on bikes, and the two of you have a hissy fit. Spare me. I don't know why I bother, so I'll stop bothering now.

...your arguments here are not based on real world conditions. Nobody rides a bike 112 miles over varied terrain without slowing and accelerating a number of times.

Originally Posted by Lombard

Originally Posted by Atlas Shrugged

The usual mud-slinging fest aside, it would be interesting to see an actual study or accurate mathematical model on the effects of a 500-gram lighter wheelset acceleration from 0 to 30kph. Then run the same test with 500 gram weight placed on the bike. My guess the difference is negligible. This myth that weight at the wheels is somehow much more relevant seems like is bs. That said the gyroscopic forces would be stronger giving the bike a different feel thus the perception it is slower.

Originally Posted by Atlas Shrugged

The usual mud-slinging fest aside, it would be interesting to see an actual study or accurate mathematical model on the effects of a 500-gram lighter wheelset acceleration from 0 to 30kph. Then run the same test with 500 gram weight placed on the bike. My guess the difference is negligible. This myth that weight at the wheels is somehow much more relevant seems like bs. That said the gyroscopic forces would be stronger giving the bike a different feel thus the perception it is slower.

Originally Posted by Atlas Shrugged

The usual mud-slinging fest aside, it would be interesting to see an actual study or accurate mathematical model on the effects of a 500-gram lighter wheelset acceleration from 0 to 30kph. Then run the same test with 500 gram weight placed on the bike. My guess the difference is negligible. This myth that weight at the wheels is somehow much more relevant seems like bs. That said the gyroscopic forces would be stronger giving the bike a different feel thus the perception it is slower.

Originally Posted by Trakhak

Different feel: I had an incredibly light set of aluminum Hi-E wheels (with rims that consisted of sheets of aluminum folded over and riveted) fitted with very light tubular/sewup tires. They accelerated fast, all right, but they always felt as if they were too light to maintain momentum from one pedal stroke to the next. Might have been in my head, but I'd swear that I could feel my cadence was more uneven with those wheels.

Ondrej Sosenka set the human-powered (i.e., Merckx-style) hour record in 2005 using an unusually heavy bike and heavy wheels. Quoting from The UCI Hour Record: Ondrej Sosenka:

"In his attempt, Sosenka was using a 54 x 13 gearing, a 3.2 kg wheel and 190 mm cranks, with his bike weighing a total of 9.8 kg. The reason for the heavy wheel was that although it was harder to get up to speed, it was easy to maintain it."

Originally Posted by Eric F

I would definitely be curious to see some accurate scientific data on that comparison. Lighter wheels/tires certainly feel easier/quicker to accelerate (to me), but I don't really notice a difference between empty and full bottles, or an extra pound on my ass.

Originally Posted by Koyote

There are several calculators like this one that allow you to quantify the effects of weight on speed, rolling time on a given course, etc...though they make no distinction between wheel weight vs static weight.

The posters who are arguing over the relevance of weight (and of different types of weight -- rotating vs static) are probably each correct, to some degree. The effects may be present, but small.

I don't see anyone arguing that bike weight (or wheel weight, more specifically) is more important than fitness and rider weight. But then, those are not mutually exclusive: when I was road racing many years ago, I did some big climbing events. I did have a relatively light set of race wheels, and I also dieted down to the low 160-lb range (lowest was 163 lbs) at 6'2" tall. I can't really say whether the low weight made me faster, because I got to that weight partly by training a lot -- which made me faster.

Originally Posted by 3alarmer

...good example of rolling weight and inertial mass. Kudos.