For comment: "Why It's Impossible For Steel Frames To Be More Comfortable..."

[colker]

Originally Posted by reuben

No fair, no fair! It's not a diamond, parallelogram, tetrahedron, or rhombus!

(Y'all done gone hog crazy! Love it.)

It helps that JOnes himself has great handling skills.

[Gummee]

Having read through the whole thread: I seriously doubt that any of us ride a bike completely vertically. I'm willing to bet that we're slightly off to one side or the other when we're pedaling.

Which would lead to flex in planes other than completely vertical

...but that's a guess because I had a bike that was super comfy and a bike that was just OK from the same manufacturer. TIGed SL and lugged SLX if you're wondering

Back to your regular discussion

M

[martl]

Originally Posted by NHAero

It seems that the engineers in this thread seem to all agree:
- that the frame is not a factor in comfort because it deflects so little
- that other components with much lower spring rates comprise the bulk of the deflection
- that different damping characteristics are irrelevant if deflection is de minimis

Do we also agree that a frame can be designed from any of the common materials with similar vertical stiffness, such that built up with the same wheels, tires, saddle, seatpost, bar tape, etc., and with the same fork, the deflection at the contact points will be the same?

We can agree that at least the second item in your list is something that Physics agrees on, not only engineers

As for the second paragaraph, in the height of the "comfort bike" hype, i offered many times that with my choice of of-the-shelf components i could take *any* rigid diamond-shape frame and build both, a very comfortable bike and a very uncomfortable one. No one ever took the challenge.

Originally Posted by vincenz

Well there’s the thing about science also— it doesn’t know what it doesn’t know until it’s known. I would agree bicycle minutiae is pretty worthless to study in the larger scheme of things, so.. maybe someone else can come along sometime and contribute with an acceptable scientific approach for this that’s not a front for begging for donations. In any case, there being a slight deflection in the frame means it is still measurable and what’s measurable is still a place to start to describe the differences that some people feel.

The bike industry has learned that something that looks scientific or hi-techy enough can help sell bikes. My notion is that very rarely actual research goes into it. Some of the bike brands on the front of this seem to struggle drilling holes that are both *concentric* and *round* for a press-fit BB (or think holding some calipers against a ball bearing tells anything about its quality), so how much confidence you have in those claims is up to you...
Funnily, most bikes still ride reasonably well which tells us a lot about the necessity of the whole thing.

Maybe, Mr Hambini of the notorious youtube channel does the honors some time. He'd be a good, yet merciless judge

Originally Posted by Gummee

Having read through the whole thread: I seriously doubt that any of us ride a bike completely vertically. I'm willing to bet that we're slightly off to one side or the other when we're pedaling.

Which would lead to flex in planes other than completely vertical

...but that's a guess because I had a bike that was super comfy and a bike that was just OK from the same manufacturer. TIGed SL and lugged SLX if you're wondering

Back to your regular discussion

M

my most uncomfortable bike is a Mike Appel made from SL, no rear chainstay braze-in and hence rather soft in the BB area. But then, it has a Brooks New Swallow and i suspect a solid oak log would be an improvement...

[Black Dog]

Originally Posted by vincenz

Well there’s the thing about science also— it doesn’t know what it doesn’t know until it’s known. I would agree bicycle minutiae is pretty worthless to study in the larger scheme of things, so.. maybe someone else can come along sometime and contribute with an acceptable scientific approach for this that’s not a front for begging for donations. In any case, there being a slight deflection in the frame means it is still measurable and what’s measurable is still a place to start to describe the differences that some people feel.

Science often knows what it does not know, in so much it is aware of the gaps in its knowledge. It is spurious to suggest that measurability is always within percievibility. Many good scientific studies that are fully independent have demonstrated the effects and non effects of the minutiae. Fortunately your skepticism has been resolved though not in line with your intuition.

[vincenz]

Originally Posted by Black Dog

Science often knows what it does not know, in so much it is aware of the gaps in its knowledge. It is spurious to suggest that measurability is always within percievibility. Many good scientific studies that are fully independent have demonstrated the effects and non effects of the minutiae. Fortunately your skepticism has been resolved though not in line with your intuition.

So go ahead and measure and define with numbers the differences between different frame materials I and others can feel, because it certainly isn't ONE number a la "vertical deflection." Create the formula to describe this ride quality/comfort and present it.

Didn't think so...

[rain dogs]

I'm not sure what is so difficult to understand about the video. It's certainly not "clickbait". The point is that the bicycle is system of parts, and that vertical deflection is the single measure that MOST contributes to/is associated with feelings of "comfort" (ie shock absorption) provided you were comparing bicycles with exactly the same components and fit characteristics. Case in point, full suspension bicycles having, wait for it.... full suspension.

In a bicycle system without full suspension, the vast majority of any shock absorption (and vertical compliance) is happening in other places, with far greater influence, than it is happening at the frame. Those being: in no particular order tires, wheels, saddle, seatpost etc.

The premise of the video is that when talking about bicycles, people/marketing often speak FIRST about frame material when it comes to comfort/vertical compliance whereas they should understand that it is likely the last place you are actually getting vertical compliance in the system and as such (any comfort associated with that compliance). And the true key point in the video is that you would need forces that are greater than the deflection of all the other component parts to start significantly flexing the frame. Put a tennis ball on top of jello and push down.... the ball certainly isn't rigid, but vs the jello it won't compress.

Furthermore, by extension, most people who aren't pros are comparatively 'slow' and do not have the same necessity for elite pro performance, so they should perhaps (if they care about comfort) direct their resources to areas of big gain (tires, wheels, saddles, seatposts etc) vs the relatively small or non existent gain in pro level, higher grade frames that claim/market huge comfort gains.

Although likely important, for Pros the last concern is comfort.... or one of the lesser concerns. They certainly don't prioritize comfort over speed, reliability, sponsor demands or safety. For normal people comfort is a bigger deal, so, don't start with the frame.... start with the tires and wheels.

[cinema]

Originally Posted by rain dogs

I'm not sure what is so difficult to understand about the video. It's certainly not "clickbait". The point is that the bicycle is system of parts, and that vertical deflection is the single measure that MOST contributes to/is associated with feelings of "comfort" (ie shock absorption) provided you were comparing bicycles with exactly the same components and fit characteristics. Case in point, full suspension bicycles having, wait for it.... full suspension.

In a bicycle system without full suspension, the vast majority of any shock absorption (and vertical compliance) is happening in other places, with far greater influence, than it is happening at the frame. Those being: in no particular order tires, wheels, saddle, seatpost etc.

The premise of the video is that when talking about bicycles, people/marketing often speak FIRST about frame material when it comes to comfort/vertical compliance whereas they should understand that it is likely the last place you are actually getting vertical compliance in the system and as such (any comfort associated with that compliance).

and, by extension, most people who aren't pros are comparatively 'slow' and do not have the same necessity for elite pro performance, so they should perhaps (if they care about comfort) direct their resources to areas of big gain (tires, wheels, saddles, seatposts etc) vs the relatively small or non existent gain in frames.

Although likely important, for Pros the last concern is comfort.... or one of the lesser concerns. They certainly don't prioritize comfort over speed, reliability, sponsor demands or safety. For normal people comfort is a bigger deal, so, don't start with the frame.... start with the tires and wheels.

That's what I got from it too. good distillation of the major points here. it's made me reconsider a lot of things I knew about the set up of a lot of my rides but was too stubborn to change.

[vespasianus]

This is timely as I have just moved from an old steel bike to a new carbon bike but because I am cheap, I reused my seatpost, seat, tires and handlebars (even the bar tape!). Granted the geometry is different but the difference in ride is noticeable. The thing that shocked me the most was that the old, dated steel fork outperforms the new carbon thing when it comes to road buzz. I thought it would have been 100% the other way around.

In terms of aluminum, anybody old enough to remember when we went from riding rigid steel mountain bikes to rigid aluminum mountain bikes? Granted those early days featured some extremes - people trying to make 2.8 lb steel mountain bike frames that were as light as possible and people making 3.1 lb aluminum frames that were as stiff as possible. And even with the same stem, handlebar, seat post, seats, wheels and tires, you could feel it easily.

[vincenz]

Originally Posted by rain dogs

I'm not sure what is so difficult to understand about the video. It's certainly not "clickbait". The point is that the bicycle is system of parts, and that vertical deflection is the single measure that MOST contributes to/is associated with feelings of "comfort" (ie shock absorption) provided you were comparing bicycles with exactly the same components and fit characteristics. Case in point, full suspension bicycles having, wait for it.... full suspension.

In a bicycle system without full suspension, the vast majority of any shock absorption (and vertical compliance) is happening in other places, with far greater influence, than it is happening at the frame. Those being: in no particular order tires, wheels, saddle, seatpost etc.

The premise of the video is that when talking about bicycles, people/marketing often speak FIRST about frame material when it comes to comfort/vertical compliance whereas they should understand that it is likely the last place you are actually getting vertical compliance in the system and as such (any comfort associated with that compliance). And the true key point in the video is that you would need forces that are greater than the deflection of all the other component parts to start significantly flexing the frame. Put a tennis ball on top of jello and push down.... the ball certainly isn't rigid, but vs the jello it won't compress.

Furthermore, by extension, most people who aren't pros are comparatively 'slow' and do not have the same necessity for elite pro performance, so they should perhaps (if they care about comfort) direct their resources to areas of big gain (tires, wheels, saddles, seatposts etc) vs the relatively small or non existent gain in frames.

Although likely important, for Pros the last concern is comfort.... or one of the lesser concerns. They certainly don't prioritize comfort over speed, reliability, sponsor demands or safety. For normal people comfort is a bigger deal, so, don't start with the frame.... start with the tires and wheels.

You're missing the point of the counter-argument. No one said his point was difficult to understand. His point was simple to the point that it is oversimplified and lacks the context to make fully the judgment in the clickbait title. Comfort cannot be solely defined using vertical deflection because that number alone cannot capture the nuance of different materials and other dynamic forces present in real riding. There's more to how a material reacts to forces other than just bending and you don't ride bicycles in a perfectly vertical plane.

When marketers speak of comfort, they do mention vertical compliance, but not in the context of different materials. Major manufacturers use carbon these days and talk about vertical compliance in different carbon layups. In any case, no one is saying those marketers aren't missing the point either, but for their context, it is appropriate as they are speaking of one material. If you, like some others, cannot feel or care about the different ride characteristics of different frame materials, then you might as well ride the lightest material as weight should be the only performant parameter when determining frame choice.

[Bob Ross]

Originally Posted by rain dogs

vertical deflection is the single measure that MOST contributes to/is associated with feelings of "comfort" (ie shock absorption)

I think if the word "comfort" had never been used and the OP and/or video producers had simply used "shock absorption" from the get-go, this thread would be one, maybe two pages long, with very little disagreement.

[rain dogs]

Originally Posted by vincenz

You're missing the point of the counter-argument.

The counter argument misses the point.

Suspension, like that on a full suspension bicycle travels in a linear plane, up and down, making the bike extremely vertically compliant, but that doesn't mean full suspension only works in that perfectly vertical linear plane or when the bicycle is perfectly vertical.

Tires for example compress when the bicycle is at a variety of angles. The forces of hitting a bump or several small bumps are happening "vertically".... they aren't coming "horizontally" (like wind for example, or a car)

When a full suspension bicycle hits an bump, all of the suspension parts compress long before the frame flexes. The low pressure tires and the suspension first and foremost as those are the most compliant pieces of the system. It compresses as well if the bike is on a steep angle, turning for example.

The same is true on a road bike, it just doesn't have the active suspension system. And vertical compliance/shock absorption/vertical deflection would be the characteristic in a frame that would be most associated with/influential on "comfort". And again, the point is that the other elements in the system are more active and influential than the frame, so any small tiny differences between frame materials, if any, are likely immeasurable, non-existent or minuscule compared to tires etc.

The point is, the "softer" elements (tires, wheels, saddle, seapost etc.) 'deflect' long before the more rigid elements like the rear triangle and have a much, much greater influence on "comfort"/shock absorption

[vincenz]

Originally Posted by rain dogs

The counter argument misses the point.

Suspension, like that on a full suspension bicycle travels in a linear plane, up and down, making the bike extremely vertically compliant, but that doesn't mean full suspension only works in that perfectly vertical linear plane or when the bicycle is perfectly vertical.

Tires for example compress when the bicycle is at a variety of angles.

When a full suspension bicycle hits an bump, all of the suspension parts compress long before the frame flexes. The low pressure tires and the suspension first and foremost as those are the most compliant pieces of the system. It compresses as well if the bike is on a steep angle, turning for example.

The same is true on a road bike, it just doesn't have the active suspension system.

The point is, the "softer" elements compress long before the more rigid elements.

First of all, MOST is not ALL. Just because a frame may flex the least vertically, doesn't mean it doesn't, and that the differences aren't noticeable between different materials. Your point misses the counter-argument point, which you chose to ignore, that it is not only this measurement that should determine "comfort." Like I said, his point was not missed. But it is oversimplified and shouldn't be used to make a human-determined value such as comfort while neglecting context within other cycling disciplines.

Originally Posted by Bob Ross

I think if the word "comfort" had never been used and the OP and/or video producers had simply used "shock absorption" from the get-go, this thread would be one, maybe two pages long, with very little disagreement.

Thank you for that, agreed. That descriptor better gets across what the number actually describes.

"Why It's Impossible For Steel Frames To Be More Shock Absorptive Than Aluminium"

"Why It's Impossible For Steel Frames To Be More Vertically Deflective Than Aluminium"

They aren't as clickbaity though.

[rain dogs]

Originally Posted by vincenz

First of all, MOST is not ALL. Just because a frame may flex the least vertically, doesn't mean it doesn't, and that the differences aren't noticeable between different materials. Your point misses the counter-argument point, which you chose to ignore, that it is not only this measurement that should determine "comfort." Like I said, his point was not missed. But it is oversimplified and shouldn't be used to make a human-determined value such as comfort while neglecting context within other cycling disciplines.

You insist that I, and a bunch of others are ignoring a point, but maybe we don't read a well articulated, valid point. What I read is an issue with semantics (also highlighted by Bob Ross), but I'm not interested in a back and forth about semantics.

Most everyone seems to have distilled the important factors out and aren't viewing this as an over-simplification as you do. The video outlines why other component parts have a much, much larger influence on the otherwise tiny, or non existent influence of the frame (if forces are even large enough to flex it)

Now, you seem to believe there are a series of other significant factors at play in a bicycle frame only*, beyond vertical compliance/shock absorption/vertical forces that influence "the human-determined value of comfort" then make your counter point. Where are they? What are they? What are these significant factors? Help me understand them.

*Assuming all the other parts of the system (components are the exact same, same wheels, same tires, same fork, same geometry, same weight, same profile, same everything just a different frames and frame material)

I'll happily read your reply, but I'm likely done trying to add to explaining this...

[slowpoke]

What's everyone's favorite Tom Waits album?

[rain dogs]

Originally Posted by slowpoke

What's everyone's favorite Tom Waits album?

Ha! What's everyone else's favorite Tom Waits album, no?