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Is steel still real?

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SlantParallelogram said:
Since you couldn't even get the simple unit conversion correct, I didn't even bother to check the math in the rest of your equations, which I am assuming is probably also totally wrong. :D

You are right! My conversions were wrong. I reversed the operation of the conversion factor of 3.6. My mistake and I admit it. Lack of attention = stupid mistake. Here is the correct math...I hope ;)

81kg (~180lbs Bike plus rider) X 0.56m/s/s (2km/h/s this is hard acceleration) = 45.36 Newtons
82kg x 0.56m/s/s = 45.92 N

45.92N - 45.36N = 0.56N and 0.56N/45.92N = 0.0122 X 100% = 1.22% less force to accelerate the 1kg (2.2lb) lighter bike. Of course this ignores wind resistance which increases the total force required, regardless of mass and thus further reduces the positive effect of a lighter bike in terms of acceleration.

So. Does 1.22% really make a noticeable difference? Now do the calculations for a few hundred grams that lighter wheels makes and you are in the range of 0.2%. Oh yea...that is some serious speed.

We since you will not read any of this SlantParallelogram because you have decided what reality is and no amount of evidence will convince you otherwise. And since my making a mistake, that has no effect of the conclusion, obviously proves you right. ;) You did not bother to put up a correction that shows the difference between bike and in stead decided to use a weak 'straw man' argument, can I assume that you are in the middle of some serious cognitive dissonance? Keep substituting your delusion for reality if it helps you win the tour next year. I can admit when I am wrong...:confused:
 
Jun 20, 2009
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Short answer, yep.

Long answer, old steel is good, new carbon is good, old carbon scares me.

I personally prefer the ride of my 2009 carbon (Colnago CX-1 with Fulcrum Racing 1s and sram red) to my lovely late 80s steel (KenEvans custom with old-school campag Ventos and DA) but they are both great.

Unless you are already down to minimal BMI, then losing a few kilos off the waistline will deliver better results than a lighter bike. Obviously low BMI plus lightweight bike is best.
 
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Black Dog said:
So. Does 1.22% really make a noticeable difference? Now do the calculations for a few hundred grams that lighter wheels makes and you are in the range of 0.2%. Oh yea...that is some serious speed.

But 1.22% per kilo does add up no? Especially if you're starting with a heavy bike! How do those numbers convert to hill climbing considerations? Is it a matter of multiplying the anticipated time by 1.22% to get the expected time savings with particular weight reductions?

I'm sceptical that a blind study would show that an experienced rider can't tell the difference between high end wheels/rubber and junk. I'm confident that I really notice a difference in ride quality and acceleration. A blind study with non-obsessive cyclists might demonstrate that they can't tell the difference between wheels, but then we never expected our spouses to understand why 6 hours of spoke research isn't a waste of time.:eek:
 
bc_hills said:
But 1.22% per kilo does add up no? Especially if you're starting with a heavy bike! How do those numbers convert to hill climbing considerations? Is it a matter of multiplying the anticipated time by 1.22% to get the expected time savings with particular weight reductions?

I'm sceptical that a blind study would show that an experienced rider can't tell the difference between high end wheels/rubber and junk. I'm confident that I really notice a difference in ride quality and acceleration. A blind study with non-obsessive cyclists might demonstrate that they can't tell the difference between wheels, but then we never expected our spouses to understand why 6 hours of spoke research isn't a waste of time.:eek:

I think you actually more likely to feel a 1.22% difference in a wheelset, or more accurately in a rear wheel, then in a frame. As long as the frame is built of the same material, and is about the same stiffness, you might not notice the weight difference. However the difference in weight in rear wheels in noticeable right away.
 
Black Dog said:
We since you will not read any of this SlantParallelogram because you have decided what reality is and no amount of evidence will convince you otherwise.

Why would I not read it? I'm hurt that you would think I could be so closed minded. :D

Here is the perfect example. Go put a disc wheel on the rear of your bike. There is NO WAY you can tell me you don't feel the extra weight and that your bike is not way harder to accelerate. However, at the same time, once you are up to speed it is easier to roll that heavy disc wheel along.

Then put the original rear wheel on your bike again and see how much more easily it can be accelerated.

I will look at the math again when I have more time. I think our disagreement lies in whether or not to factor the weight of the rider in to the equation. Of course in real world terms that must be included.

However, as far as how a fast a wheel feels, all you would need would be the weight of the wheel. If you switch to a rear wheel that is 20 percent lighter, then it will take 20 percent less force to accelerate it. That is something you will definitely feel.

I admit that you probably would not feel nearly as much of a difference if you switched to a frame that was 20 percent lighter (assuming everything else like the stiffness was the same). I still think it would be enough to notice.
 
SlantParallelogram said:
Why would I not read it? I'm hurt that you would think I could be so closed minded. :D

Here is the perfect example. Go put a disc wheel on the rear of your bike. There is NO WAY you can tell me you don't feel the extra weight and that your bike is not way harder to accelerate. However, at the same time, once you are up to speed it is easier to roll that heavy disc wheel along.

Then put the original rear wheel on your bike again and see how much more easily it can be accelerated.

I will look at the math again when I have more time. I think our disagreement lies in whether or not to factor the weight of the rider in to the equation. Of course in real world terms that must be included.

However, as far as how a fast a wheel feels, all you would need would be the weight of the wheel. If you switch to a rear wheel that is 20 percent lighter, then it will take 20 percent less force to accelerate it. That is something you will definitely feel.

I admit that you probably would not feel nearly as much of a difference if you switched to a frame that was 20 percent lighter (assuming everything else like the stiffness was the same). I still think it would be enough to notice.

You have to include the rider because bikes do not drive themselves (All conspiracy theories about Cancellera aside :D). Also lighter wheels reflect a 0.1% change in force needed to accelerate the bike+rider. And 20% lighter wheels are easier to accelerate by 20% if there is no bike or rider. Otherwise the difference is very very very small. Like spilling out 1/3 of the contents of a water bottle. Can anyone claim that they can feel the difference in acceleration after sweating for 1/2 hour? This can easily be 200ml of water lost which weighs 200 grams.

No hard feeling Slant. I am not getting my knickers in a knot over all of this...:)
 
Black Dog said:
You have to include the rider because bikes do not drive themselves (All conspiracy theories about Cancellera aside :D). Also lighter wheels reflect a 0.1% change in force needed to accelerate the bike+rider. And 20% lighter wheels are easier to accelerate by 20% if there is no bike or rider. Otherwise the difference is very very very small. Like spilling out 1/3 of the contents of a water bottle. Can anyone claim that they can feel the difference in acceleration after sweating for 1/2 hour? This can easily be 200ml of water lost which weighs 200 grams.

No hard feeling Slant. I am not getting my knickers in a knot over all of this...:)

I agree with everything you said, EXCEPT that you can not feel the difference.

With a disc wheel on your bike it feels like you have a boat anchor on it. Then once you getting rolling, all the inertia seems to keep you rolling along.

Switching from a set of clinchers that you train on to a set of super lightweight tubular race wheels, and your bike feels like a rocket.

Actually during the last laps of a criterium you will see guys emptying their water bottles to save the weight. In the Pro Tour you will see guys throwing out their water bottles before the sprint.
 
SlantParallelogram said:
I agree with everything you said, EXCEPT that you can not feel the difference.

With a disc wheel on your bike it feels like you have a boat anchor on it. Then once you getting rolling, all the inertia seems to keep you rolling along.

Switching from a set of clinchers that you train on to a set of super lightweight tubular race wheels, and your bike feels like a rocket.

Actually during the last laps of a criterium you will see guys emptying their water bottles to save the weight. In the Pro Tour you will see guys throwing out their water bottles before the sprint.

You are right about the disk wheel. They are usually 500 grams heavier than a spoked wheel and there is a lot of rotational mass to overcome. You can feel the slight difference. Tossing the bottles is an odd habit that does very little for acceleration. Just because they do it does not mean that it makes a difference. Pros are just as likely to do something because it has always been that way.
 
Black Dog said:
You are right about the disk wheel. They are usually 500 grams heavier than a spoked wheel and there is a lot of rotational mass to overcome. You can feel the slight difference. Tossing the bottles is an odd habit that does very little for acceleration. Just because they do it does not mean that it makes a difference. Pros are just as likely to do something because it has always been that way.

Water is really heavy. How much does the average water bottle hold? I would bet close to half a liter, so that is a little over a pound.

The average clicher rim seems to be around 440 grams, whereas even 25 years ago Mavic was selling GEL280 tubular rims that only weighed 280 grams each. I know, I had a pair and they were really light, and accelerated so fast. So that is a savings of 320 grams of rotational weight without even considering the weight of the tires. Tell me you won't be able to feel that! :p

A cheap training clincher probably weighs close to 300 grams without a tube. A tube weighs about 100 grams. Compare that to a lightweight sew-up tire that weighs 275 grams including the tube. So that is 250 grams of savings there.

So that is 570 grams of savings in rotational mass for a lightweight set of tubulars compared to a set of training clinchers. That doesn't seem like much weight, however you can definitely feel it in the way the bike accelerates out of the corners.

Even if there really is only a 1 or 2 percent difference in Force required to get the same acceleration, it is still significant. If there is a criterium with 4 corners, that is 8 percent more force per lap. It all adds up. It only takes 12 laps for that to add up to 100 percent, so every 12 laps you would be saving one corner worth of acceleration. You don't think that is worth it?
 
SlantParallelogram said:
Water is really heavy. How much does the average water bottle hold? I would bet close to half a liter, so that is a little over a pound.

The average clicher rim seems to be around 440 grams, whereas even 25 years ago Mavic was selling GEL280 tubular rims that only weighed 280 grams each. I know, I had a pair and they were really light, and accelerated so fast. So that is a savings of 320 grams of rotational weight without even considering the weight of the tires. Tell me you won't be able to feel that! :p

A cheap training clincher probably weighs close to 300 grams without a tube. A tube weighs about 100 grams. Compare that to a lightweight sew-up tire that weighs 275 grams including the tube. So that is 250 grams of savings there.

So that is 570 grams of savings in rotational mass for a lightweight set of tubulars compared to a set of training clinchers. That doesn't seem like much weight, however you can definitely feel it in the way the bike accelerates out of the corners.

Even if there really is only a 1 or 2 percent difference in Force required to get the same acceleration, it is still significant. If there is a criterium with 4 corners, that is 8 percent more force per lap. It all adds up. It only takes 12 laps for that to add up to 100 percent, so every 12 laps you would be saving one corner worth of acceleration. You don't think that is worth it?

I tried to find the article way back in Bike.com, before the dot-bomb bust but they did a study where the measured the energy required to spin a rim to a certain speed. 300 gram rim and 600 gram rim and found the energy increase was something on the order of .1 of 1% more. It's there but small, particularly on rims that rotate relatively slowly.
 
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We've always been told that saving rotational weight is worth more than weight at the core and though some have called that a myth, I've yet to see anything to disprove it. I've also always believed in a kind of leverage effect of weight and because of this saving a pound off of a bicycle has a greater effect than a pound off of the rider's stomach. Weight closer to the "core" is easier to move than weight hanging way out on the end of a bicycle and this influences bike handling (this is why many prefer to carry weight in backpacks as opposed to hanging off the bike in panniers). So changes in component weight should be more perceptible than changes in frame weight or rider body weight!
 
stephens said:
We've always been told that saving rotational weight is worth more than weight at the core and though some have called that a myth, I've yet to see anything to disprove it.

I have also seen that. Although I have not found anything to prove or disprove that either. One thing is for sure. I didn't hear that in physics class. I have however read it in cycling magazines. Anyway, I have no clue whether that is really true or not.

However, it definitely feels true! A light pair of wheels is noticeable right away. A light frame is not as easily detected.
 
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It was in physics, it is called the moment of inertia
Then there is another concept that in cars we call Rotational dynamics. It is basically used on fast moving heavy components like the flywheel to show the effect of lightening in low gear 1 kg off a flywheel (say 300mm diameter) has the effect of taking 30+kg of a chassis for the purpose of acceleration, I have a simplified formula for that. Not sure how relevant it is for a bike wheel, because it is based on a simple disk, where a wheel has weight on the outside and the hub and virtually none in between. The concept is the same though, plus the further the weight is from the centre the greater the effect it has

Moment of Inertia is too long ago for me to remember but it is a reflection of the stored energy.
In summary for two identical diameters the weight increase (with the increase in the same radius from the axis) has a linear effect on energy (ie double the weight and double the energy stored) while to double the speed you 4 fold the energy. (Which is why it is so important to engines @ 7000 rpm, bike wheels are more like 300 rpm)
Now, since the rider has to but that energy in...

Since with a rider we can say the energy supply is a constant in summary light wheels will accelerate faster, while heavy wheels will hold more energy, which means they will roll longer.
 
stephens said:
We've always been told that saving rotational weight is worth more than weight at the core and though some have called that a myth, I've yet to see anything to disprove it. I've also always believed in a kind of leverage effect of weight and because of this saving a pound off of a bicycle has a greater effect than a pound off of the rider's stomach. Weight closer to the "core" is easier to move than weight hanging way out on the end of a bicycle and this influences bike handling (this is why many prefer to carry weight in backpacks as opposed to hanging off the bike in panniers). So changes in component weight should be more perceptible than changes in frame weight or rider body weight!

'Should' but isn't. The energy it takes to accelerate a bike and rider depends on the mass of the bike and rider. It doesn't really matter where the weight is. A 15 pound bike with a 180 pound rider is the same as a 20 pound bike and a 175 pound rider. Where weight is may effect handling but has no effect on acceleration. AND remember these changes are teeny. Saving 200 grams may sound like a lot but when considering the rider/bike 'package' is 85,000 grams plus or minus(mostly plus), those 200 grams mean almost nothing.
 
SlantParallelogram said:
Water is really heavy. How much does the average water bottle hold? I would bet close to half a liter, so that is a little over a pound.

The average clicher rim seems to be around 440 grams, whereas even 25 years ago Mavic was selling GEL280 tubular rims that only weighed 280 grams each. I know, I had a pair and they were really light, and accelerated so fast. So that is a savings of 320 grams of rotational weight without even considering the weight of the tires. Tell me you won't be able to feel that! :p

A cheap training clincher probably weighs close to 300 grams without a tube. A tube weighs about 100 grams. Compare that to a lightweight sew-up tire that weighs 275 grams including the tube. So that is 250 grams of savings there.

So that is 570 grams of savings in rotational mass for a lightweight set of tubulars compared to a set of training clinchers. That doesn't seem like much weight, however you can definitely feel it in the way the bike accelerates out of the corners.

Even if there really is only a 1 or 2 percent difference in Force required to get the same acceleration, it is still significant. If there is a criterium with 4 corners, that is 8 percent more force per lap. It all adds up. It only takes 12 laps for that to add up to 100 percent, so every 12 laps you would be saving one corner worth of acceleration. You don't think that is worth it?

Again, one pound plus or minus to the bike plus rider package is not significant on a flat course in terms of acceleration. Therefore water bottle tossing is an old wives tale.

As for the 1-2 percent thing. You can not add a 2 percent difference for each corner and say that the difference is 8%! Add it up for every corner of a 60 lap race and you will get 480%!!! Oh my! How does a guy who weighs 1 kilo more than the next guy even get his bike off the start line? It does not work that way. It will always be 2%.

How about comparing the light tubular to a light clincher? That would be fair. Comparing the light tubular to a locomotive wheel is not.
 
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Acceleration isn't everything. Lots of other things come into play in regards to how well the bike handles and simply how much fun it is to ride.

And I think this is where the lever comes into play: the farther something is away from my core, the bigger difference its weight makes in my ability to move it around. Very obvious when mountain biking, but not insignificant in the type of real world "road" cycling many of us do.

(for example, on a mountain bike I'd rather carry 15 lbs. in a securely fashioned backpack than have wheels that weigh 5 lbs. more).
 
The difference between steel and C is less than the difference between most people's weight variation during the day. I have a steel Ritchey Breakaway and a carbon Fuji SL/1 and while the Fuji is surely faster uphill by a few %, that hardly affects the ride experience, and I've ridden the Ritchey far more this year. Why? It's far more robust and can be easily repaired if it becomes damaged, while the carbon is prone to fatal cracks.

The Ritchey handles great and with SRAM Rival and regular Al clincher wheels it's a very reasonable 17.5 lb. It sometimes leaves me wondering why I hang on to the Fuji.
 
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djconnel said:
The difference between steel and C is less than the difference between most people's weight variation during the day.

Pace to Bustedknuckle from a couple of posts back, but weight on a bike must affect climbing differently than weight on the ar$e. High end ski touring boots will save a couple of pounds over regular boots, and the difference is like night and day. Isn't it the same with a frame or wheels? 5 pounds of body weight compared to five pounds on the bike must be two different things, no? For me it's completely counter-intuitive to think otherwise, or maybe bike weight is so "marketed" into me that it just seems counter-intuitive.
 
bc_hills said:
Pace to Bustedknuckle from a couple of posts back, but weight on a bike must affect climbing differently than weight on the ar$e. High end ski touring boots will save a couple of pounds over regular boots, and the difference is like night and day. Isn't it the same with a frame or wheels? 5 pounds of body weight compared to five pounds on the bike must be two different things, no? For me it's completely counter-intuitive to think otherwise, or maybe bike weight is so "marketed" into me that it just seems counter-intuitive.

No. It doesn't matter when lifting the bicycle/rider combo up a hill. The idea that 1 pound of frame weight is somehow bigger or smaller than 1 pound of body weight or what's in your pocket is reinventing physics. A bicycle goes slowly, powered by a person. Weight is weight, regardless where it is. Putting 5 pounds in your jersey pocket will have the same effect as riding a 20 pound bike rather than a 15 pound bike, with regards to energy required to move the 'package'.

Marketeers will tell you different, particularly wheel marketeers but lying in advertising is a high art.
 
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Bustedknuckle said:
No. It doesn't matter when lifting the bicycle/rider combo up a hill. The idea that 1 pound of frame weight is somehow bigger or smaller than 1 pound of body weight or what's in your pocket is reinventing physics. A bicycle goes slowly, powered by a person. Weight is weight, regardless where it is. utting 5 pounds in your jersey pocket will have the same effect as riding a 20 pound bike rather than a 15 pound bike, with regards to energy required to move the 'package'.

Marketeers will tell you different, particularly wheel marketeers but lying in advertising is a high art.

Every time a discussion of weight comes up, a few people have to get on here and take the position that they know better than everyone else in the world and that all of our experiences are wrong and our perceptions flawed and if we find riding lighter bicycles to be faster or more enjoyable then we're just falling prey to marketing hype. And that if only we were as smart as they were we'd see that "weight is weight, regardless where it is," and that weight off the bike isn't any different than weight off the riders fat ***.

Oh yeah? Tomorrow carry your things not in a briefcase in your hand or in a backpack on your back, but hanging on the end of a 1-meter stick. Grab the other end of the stick and pick up your stuff. It's the same weight, sure. But how does your arm feel by the time you get to work? And do you still feel that weight is weight, regardless where it is?"

Personally I think the people who argue this way are like the people who insist that all bodies fall to earth (or all bikes roll downhill) at the same speed regardless of their weight because they (think they) learned it in school. It's some sort of simplistic, textbook "in a vacuum" understanding of physics that does not hold in real world conditions. Similarly, if they were to draw up all the vectors involved in riding a bike, they'd see that weight off the bike really does matter more than weight off the riders gut or out of his water bottle, and that weight off of certain parts of the bike matter more than weight off other parts.
 
stephens said:
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Every time a discussion of weight comes up, a few people have to get on here and take the position that they know better than everyone else in the world and that all of our experiences are wrong and our perceptions flawed and if we find riding lighter bicycles to be faster or more enjoyable then we're just falling prey to marketing hype. And that if only we were as smart as they were we'd see that "weight is weight, regardless where it is," and that weight off the bike isn't any different than weight off the riders fat ***.

Oh yeah? Tomorrow carry your things not in a briefcase in your hand or in a backpack on your back, but hanging on the end of a 1-meter stick. Grab the other end of the stick and pick up your stuff. It's the same weight, sure. But how does your arm feel by the time you get to work? And do you still feel that weight is weight, regardless where it is?"

Personally I think the people who argue this way are like the people who insist that all bodies fall to earth (or all bikes roll downhill) at the same speed regardless of their weight because they (think they) learned it in school. It's some sort of simplistic, textbook "in a vacuum" understanding of physics that does not hold in real world conditions. Similarly, if they were to draw up all the vectors involved in riding a bike, they'd see that weight off the bike really does matter more than weight off the riders gut or out of his water bottle, and that weight off of certain parts of the bike matter more than weight off other parts.

Newton is laughing.
 
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I weigh 7 or 8 steel bikes. If I weighed one less, I might worry more about my bike weight. As it is, steel is my frame of choice for lots of hours on the bike. It may be nostalgia, or that I am cheap, but I am about to put 5 times the original price of the complete bike in groupset on an old steel frame that I just happen to like.

Oh, and stephens, for the moving parts (at least rims) there is some truth in what you say, it takes more energy to get more weight up to speed, but the frame weight is just as static as the rider weight.
 
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Bustedknuckle said:
Newton is laughing.

Yes, quite possibly, at you.
Amazing you you conveniently ignore some facts presented to you as it suits.
You always come back to "Take 200 grams of the wheels, then take 200 gram of the rider, it has the same effect."
Except it doesn't for the two reasons out lined, (Moment of Inertia and Rotational Dynamics)THEY are facts
What's more the rider is actually a constant.

Same rider 90 kg on Bike A which weighs 10kg, inc 2 kg wheels (100kg total) and Bike B with 8 kg inc 2 kg wheels. The difference is not just the 2% (for those reasons outlined), and even if it was Bike A would still be faster! (That is the Moment of Inertia)
Quite simply Bike A requires more energy to accelerate, since the constant (the rider) supplies that energy it must be slower

If we compare Bike B, with another Bike C, which is 8kg but with 1.5kg wheels, so the same total weight, then this bike has a further benefit (due to Rotational Dynamics) that requires less energy for the wheel to be accelerated, however, on a perfectly flat course this will be negated because the wheel will roll longer (this is also called a flywheel effect)... if it is perfectly flat, that is...


Now none of this has anything to do with the initial question, but that is a long way gone now