Eric F 

I'm actually not disputing the facts you're trying to push - zero/minimal difference in compliance in the vertical plane. My point is that the forces that contribute to comfort do not only happen when acting on the frame in the vertical plane. Expand your mind, man.

Nope. Cornering/turning happens when pedaling very frequently when riding a bicycle. Not all turns are leaned over enough to require the rider to stop pedaling. An important factor that you might be missing is that even pedaling a bike in a (relatively) straight line exerts lateral and torsional forces on the frame. The force on the pedals is not aligned with the vertical axis of the frame. How the frame reacts to those forces and transmits vibrations back to the rider has an effect the perceived comfort of the ride.

Stop trying to stuff everything into boxes. A human riding a bicycle is a constantly dynamic activity.

Eric F 

As someone who has taken all of the parts from one bike, and put them on another, multiple times, my experiences is that there was definitely a difference I could perceive every time I made a change. How much was related to differences in geometry, and how much was frame material, I'm not able to tell you in a meaningful way. I had aluminum bikes that felt harsh and nervous, aluminum bikes that felt soft and relaxed (comparatively), and CF bikes that felt different ways. While I don't completely agree (based on my personal experiences) that the frame doesn't matter, I would agree that the frame material might matter less to comfort than the marketing folks would have you believe. An uneducated conclusion I've come to is that a frame's lateral stiffness plays a fairly meaningful role in the net result.

79pmooney

I regularly move parts from one frame to another. The ride changes. My ti bikes have nearly the same parts as my steel bikes. Again, different rides. I feel those differences. And I've been told for many years my body is wrong; that I cannot.

I loved the sublime ride of the old tubular rims and sewups. That didn't happen over my 25 years on clinchers with Open Pro rims and the like; all of which were much stiffer than the old shallow tubular rims. The later tubular GP4s are also deeper and aren't quite as sublime a ride on rougher road surfaces. Another place I noticed the difference was on Cycle Oregon when I hit a potholed stretch going quite fast. On those tiny, rock hard tires. I hit a far pothole edge hard. This would have been a real shock with my previous Open Pros unless I was running modern pressures and with those skinny tires (biggest frame allowed) put me very close to pinch flat. Instead, the bike took that hit completely in stride. And it was "oh yeah! I remember this from my racing days."

You can tell me I'm imaging things but my bikes and body tell me otherwise. If the test don't back me up, well maybe they are not looking at what matters.

TC1

First off, if pedaling your bike produces significant vibrations that are sufficient to make your bike uncomfortable to ride, clean or replace your bottom bracket bearings, because there must be gravel or something inside. The pedals on a properly-maintained bicycle turn with no such vibration -- and even if they didn't, are isolated from the frame by grease and bearings. Do you use special, audiophile grease on your bikes to assure that all the vibrations are faithfully reproduced by your bearings?

Second, those lateral and torsional forces still do not matter to the rider's comfort -- so this is not "an important factor" in any way, shape, or form.

Some things belong in boxes. Other things belong in landfills, such as the long-since disproven idea that material selection affects the ride quality of a rigid double-triangle bicycle frame.

You might not like that fact, much like audiophiles famously cannot come to grips with the fact that fancy speaker wires do not have any audible effect, but science does not care what you like.

Eric F 

Thank you for confirming that you don’t understand much about the operation of bicycles in the real world.

TC1

And some people swear they can hear the difference between digital audio sources -- which is also impossible. You could not detect those alleged differences in a double-blind test of your bikes, because they are physically impossible, even if your brain has been completely convinced that your new purchase was miles better than your old one.

The simple fact that you claim there was a significant difference "every time" is evidence enough that you are a victim of confirmation bias -- and there's no shame in that, everyone is susceptible to it, but intelligent people recognize the phenomenon. To quote S Wonder, "When you believe in things / that you don't understand / then you suffer."

TC1

With respect, "No **** Sherlock". That's what science tells us -- the components are responsible for the ride quality.

And those people who have told you that, are correct. Please see my preceding response on the topic of "confirmation bias", from which you are also suffering. ( And I use that term loosely -- if it makes you happy to believe in your titanium religion, great, more power to you, everyone wants to be happy... just don't run around proselytizing that nonsense which has long-since been proven to be false. )

Come on guys, this is not rocket science, nor is it even particularly recent science. We have known the properties of these materials and shapes for many years. You are describing fantasy.

TC1

Hey, big talk from the guy whose pedals apparently grind like a coffee machine.

Ironically, that same "real world" excuse is constantly used by audiophiles to defend their purchase of thousands of dollars of cables that cannot make any audible difference. They almost always fall back on the same story -- "Well I can't explain why all the science says otherwise, but I KNOW I can hear the difference in the real world." It is very difficult, as this thread illustrates, for some people to admit that they've been taken for a ride -- financially and figuratively speaking -- and/or that closely-held beliefs are in-fact nothing but superstition.

Eric F 

You’re not helping your case by extrapolating my use of the word “vibrations” into something that I clearly was not talking about. There might not be a meaningful measurable difference between materials in the vertical deflection of a standard bike frame tested in laboratory conditions (I have not argued against that), but limiting yourself to only the results of only that one data point to determine ride “comfort” shows a lack of understating of the other forces involved with making a bicycle move down the road, and how we interact with it.

As for speaker wire, I’m a 12ga stranded copper guy. I also believe that Bluetooth does a sufficient job transmitting audio data across the room for my needs. I do spin vinyl records, on occasion, but it’s about the nostalgic ritual of it, not some belief in superior audio quality. I am mildly picky about speaker placement and decent stereo imaging, however.

Eric F 

You’re getting so lost in your little box that reading comprehension is leaving you.

He took the parts from one frame and put them on another frame. Same parts, different frame, different feel. The parts/components variable is eliminated. The differences might be measurable, but you have to look beyond just vertical compliance data.

base2 

If ever you wondered: "Oh, wow...How can seemingly sane, rational people/person think irrational preposterous thing (X)?" There is almost always a sure-fire guarentee that somewhere along the way a fundamental, foundational concept or critical piece of information that has been missed.






But since TC1 apparently watched a Youtube video once that makes him the one and only sole authority on the matter... And since no one here is as worthy or credible in adding depth of meaning or nuance to the knowledge given with God level authority bestowed upon TC1 by the Youtubes. Here is another video from the only source that TC1 finds credible.


TC1 Here is a bit of news: Nobody is buying a steel or titanium or carbon, or bamboo, or wood, or whatever frame material because of they thought they were buying "vertical compliance" of the frame. That you seem to think that we think "vertical compliance" is the defining characteristic of comfort in spite of all the posts to the contrary says a lot more about you than it does about the collective.

TC1

So what were you talking about when you claimed that pedaling a bicycle induces vibrations that are sufficient to discomfort the rider? I am not aware of any properly-maintained crankset system for which that would be even close to true.

Forces moving the bicycle down the road are irrelevant to comfort. Forces moving the bicycle up off the road are relevant.

And, for the record, if you believe that your frame is more flexible than your tires even laterally, perform a simple test. Push your thumb into your inflated tire, and see it deflect. Now push secure your frame in a jig, and push your thumb against it -- and see it not deflect.

TC1

Yes, but post-purchase superstition has an amazingly-strong hold on some people, as I just said.

Are you referring to the difference between "vertical" and "lateral"? That's a very "fundamental, foundational" concept and you seem to have missed it.

No one has suggested that bicycle frames do not deflect laterally, as shown in your video. That, however, has nothing whatsoever to do with comfort.

Eric F 

What you aren’t acknowledging - or are refusing to acknowledge - is that some people may be more sensitive to certain sensations than others. Some of it is related to having enough experience to have a frame of reference to recognize the differences. For people without a frame of reference, it’s easy to just deny that differences exist…and then quote some study that confirms their bias.

TC1

That's your assumption, but that's not what he wrote. He wrote: "I regularly move parts from one frame to another. The ride changes."

So, on the one hand, we have the confirmation bias explanation -- a phenomenon well-known to science since Thucydides ( a long time, for the non-scientific readers out there ). And, on the other hand, we have the superstitious belief that under certain unknown, impossible-to-describe circumstances, bicycles frames become more pliable than pneumatic tires -- a phenomenon which has never been observed by science, and is supported by no known hypothesis.

Hmmm... which is likelier to be correct?

TC1

What you are apparently unable to understand is that the "frame of reference" for those people who tell you that the difference does not exist, is science.

Superstition is not a reasonable alternative.

The science remains brutally clear, despite the attempts at superstitious obfuscation. It requires many thousands of Newtons of force to deflect a bicycle frame, and two orders of magnitude less force is required to deflect pneumatic tires to failure. Until and unless your superstition can work its way out of that box, it remains nothing but wishful-thinking. There is no human capable of sensing deflection that cannot happen, despite your hopes, I'm afraid.

Eric F 

Keep going! I can’t wait to see what else you come up with next. You have a fantastic imagination!!

vespasianus

Classic bikeforum thread. God love this site. The most comical thing is the statement that the "science" shows, with the science being single report from a web-site called "Cycling About".

base2 

I said as much in post number 9
I then identified some common trends of behavior
Then, I suggested where more effective efforts could be directed
Then I gave a suggestion of where possibly the misconception originated:
...and followed it up with popular design innovations to support the hypothesis.
The conclusion:
So, you tell me, who exactly that is it that is being the rube here? What, if any, are the points presented that you take issue with? Where is the threads misunderstanding? Educate me. Educate us all.

TC1

I do, in-fact, have a fantastic imagination, but I'm not using it here -- I'm just trying to teach you rather basic physics, and a little psychology.

And you keep resorting to ridiculous posts like that one, filled with ad hominem attacks in lieu of any sort of useful contribution.

Eric F 

”We measured one factor, and found no difference between materials” is scientific, but isn’t necessarily significantly relevant to the real world experience of humans who experience a multitude of different sensations simultaneously, at multiple contact points.

Your belief that a frame cannot bend because of tires (or other components) in the pathway between power and ground is another confirmation that you’ve never ridden a bike hard enough make a frame bend.

base2 

Heh. Yeah. I picked that one on purpose.

TC1

If you were even the slightest bit informed on the topic, and/or had even read that article, you might be aware that the science is vastly more widespread than you suggest -- not that it even needs to be, as one can confirm the findings in their own garage, if need be. But you'll probably insist on clamping your hands over your ears and wailing "I can't hear you", so I'll leave you to your delusions.

TC1

Then you went on to post a video of lateral deformation, and insinuate that it was somehow relevant to the conversation -- along with calling the position that you are now seemingly agreeing with "irrational" and "preposterous". So, to put it mildly, make up your mind.

I have been trying to educate you all -- but with some of you, it might be easier to educate a rock, or a stump. Or, more precisely, to talk a devout believer out of the existence of God, or Bigfoot.

I did not disagree with all your post #9, that you laboriously quoted, and you'll note that I did not respond to it. Some of it didn't make any sense, but it wasn't worth my time to argue points not germane to my position. For example, you wrote:

In that paragraph, you partially support what I've been educating folks on -- which is that components are responsible for ride quality -- but then go on to claim that carbon fiber bikes have poor ride quality, when one of their alleged selling points is exactly the opposite. Now, I could have used this inconsistency to illustrate that all these notions of frame material effecting ride quality are nonsense, because even the believers can't keep their stories straight, but that was not worth my time, so I skipped it. If I called-out every bit of nonsense in this thread, I might burn out the servers that host this site.

TC1

You'd sound much more like you have a clue, if you, ya know, had a clue about the relevant science. That's not an accurate description. An accurate description would be: "We've measured the force required to deflect thousands of different frames, and in every case, the required force is two orders of magnitude greater than the force required to deflect the other components in the system."

I never have, and neither has anyone else since the development of pneumatic tires. Again, I am not offering my opinion here, this has been proven, time and again, over decades.

And by the way, you're again misrepresenting the situation. "Power" has nothing whatsoever to do with this problem.