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

[vincenz]

Originally Posted by Mark McM

Okay, maybe we need to narrow down what the video means by "comfort." Since it also talks about seat post flex, I'm pretty sure what is being addressed is comfort at the saddle. Frames can vary quite bit in flex to out-of-plane forces. But does applying large out-of-plane forces really affect comfort? I know I that "comfort" has no meaning when I apply large out-of-plane forces.



To make this a closer analogy to a bicycle, say you were wearing either rubber or cotton under a suit of armor. There could be a large difference in comfort between the the cotton or rubber layers between you and the armor, but it wouldn't make a whit of difference whether the armor was made of steel or iron.

He doesn't go over it specifically in the video because he either left it out intentionally or just neglected it, neither of which are correct methodologies for the judgment he was making, but it makes for a good clickbait title.

I can't completely match up your addition to the analogy because we're still talking about the frame material and not other components, but I'll leave it at that. All I know is I can tell a difference between frame materials in comfort and I'm sure many others can also. Many others may not as well, and that's fine.

Originally Posted by spoonrobot

The frame is the fork. Ride long enough and all the conventional wisdom is true.

Is that how you ride bikes? I thought we weren't supposed to use forks or wheels or any other components.

[reuben]

Originally Posted by Mark McM

To make this a closer analogy to a bicycle, say you were wearing either rubber or cotton under a suit of armor.

With all due respect, I don't think that anyone here rides a bicycle while wearing a suit of armor, so I'm not at all sure how that makes it a "closer analogy".

But the image it conjured in my mind did make me chuckle.

[reuben]

Originally Posted by vincenz

Is that how you ride bikes? I thought we weren't supposed to use forks or wheels or any other components.

Clearly the rear fender is the key component. Stiff, yet flexible. Soft, yet rigid.

[Mark McM]

Originally Posted by reuben

With all due respect, I don't think that anyone here rides a bicycle while wearing a suit of armor, so I'm not at all sure how that makes it a "closer analogy".

You kind of do. You ride with a structure made of rigid metal (or carbon fiber - which is also sometimes used for armor) between you and the road. Which, as far as load transfer and shock absorption, is very much like a layer or armor.

[reuben]

Originally Posted by Mark McM

You kind of do. You ride with a structure made of rigid metal (or carbon fiber - which is also sometimes used for armor) between you and the road. Which, as far as load transfer and shock absorption, is very much like a layer or armor.

If I rode wearing a suit of armor, I'd need a COMPLETELY different kind of chamois.

[colker]

Originally Posted by martl

Definitely marketing. A bike frame is 11 tubes connected. If someone sees a whiff of a chance to do something a tiny bit different than the competition which does 99.9% the exact same product, they will. The bull****ters from marketing will explain the customer why "different" has to be better.
Its a common thing ever since the market changed from "lets sell this person a bike and sell him another one in 20 years from now" to "market sesearch says the average consumer is willing to fork out $$$ for a new item on average every 3 years if we give him enough incentive to lie to himself that theres a noticeable improvement (works in other fields of the hobby/consumer market as well, skis, cars, tv sets, etc. etc...)

Can you explain how any of the variations Clancy mentioned should do anything to "brake efficiency"?

Calling Mr. David Kirk at the front desk please...

[slowpoke]

Originally Posted by spoonrobot

The frame is the fork. Ride long enough and all the conventional wisdom is true.

"A fork is the most critical part of the bike. If the fork is absorbing energy and absorbing energy correctly, it's going to give you a big part of the feeling from the ride that you're going to enjoy or value. So because steel has a unique flexing characteristic, it can be designed differently than carbon fiber and aluminum and other materials.

And as a frame builder, one of the most important things in the designing of a bike previous to anyone introducing carbon fiber was designing the fork in a way that when you did have an accident, the fork would bend and the frame would not. And so there's a whole science behind that and so you could straighten a steel fork. You couldn't straighten a steel frame. The frame required a lot more repair and difficulty in repairing it than a fork. A fork a replaceable or it was actually fixable. You could bend it. And the energy that it absorbed as a one-inch steering column was a unique thing. It would absorb more energy than a carbon fork.

A carbon fork, all the testing standards--what people don't know, the dirty little secrets about the carbon fork--is the testing standards have changed by a factor of two. They have to be twice as stiff in the CEN testing standards because if they're not, they break. A steel fork bends. And so you have to do all kinds of other things to the frame in order to keep the frame from breaking or from bending." - Tom Ritchey

https://www.youtube.com/watch?v=V-gGIqfVB2Y&t=1984

[Mark McM]

Originally Posted by spoonrobot

The frame is the fork. Ride long enough and all the conventional wisdom is true.

Hey, that's a really awesome video! It clearly shows that the fork is flexing (and that the rest of the frame really isn't - especially the rear triangle).

This is going off topic a bit, but -

To my eye, the thing that stands out the most is that it sort of looks like the fork is "pivoting" forward and back at the headset/crown, almost as if there was "hinge" there As the fork blades flex forward and back, there is very little change in the actual shape of the blades. This illustrates something that I keep saying - in most cases the majority of the flex in a fork is in the steerer, (plus a smaller bit at the crown and the tops of the legs), but that the curve in the lower part of the fork adds very little to fork flex.

[Dino Suegiù]

Originally Posted by reuben

If I rode wearing a suit of armor, I'd need a COMPLETELY different kind of chamois.

Maybe you are shopping at the wrong armor shops then, because the latest consensus on this thread, if am following, seems to be that steel frames are indeed more comfortable if one wears an untucked shirt, semi-skinny jeans, and Vans shoes aka "modern armor, but super comfy too!"? (The chamois is still an unknown, though, and so you do make a very salient point regarding that.)

But from what I have gathered so far, the only thing separating that fellow from absolute comfort-nirvana, or as close as one can get to that transcendent state, is that his bike is not also yellow. Imagine his dismay when he reads this thread....

[benb]

Didn't watch the whole video but he shows a closeup of the Specialized CG-R seatpost that has the built in spring damper thing.

That kind of seatpost will make a bigger difference than any non-sprung seatpost or rigid diamond frame feature.

Also stuff like the features in a Specialized Roubaix or a Trek with the ISOSpeed beams... those all really break the rules around these kind of frame debates.

Obviously forks flex a lot.

[spoonrobot]

Originally Posted by Mark McM

Hey, that's a really awesome video! It clearly shows that the fork is flexing (and that the rest of the frame really isn't - especially the rear triangle).

This is going off topic a bit, but -

To my eye, the thing that stands out the most is that it sort of looks like the fork is "pivoting" forward and back at the headset/crown, almost as if there was "hinge" there As the fork blades flex forward and back, there is very little change in the actual shape of the blades. This illustrates something that I keep saying - in most cases the majority of the flex in a fork is in the steerer, (plus a smaller bit at the crown and the tops of the legs), but that the curve in the lower part of the fork adds very little to fork flex.

I agree. Most production steel disc forks are going to be very stiff in the legs and only flex at the crown. Rarely, especially now, there are lighter ones that will flex at the legs. This is a soma champs elysses low-trail disc QR disc fork that has very obvious flex at the legs. Probes were mounted 5mm apart at mid-blade eyelet and dropout eyelet. I pushed down on the drops and had the tire compress about 40% with the bike on a bathroom scale that was zinging up and down to about 50 pounds. This is the most compliant fork of any kind I've ridden.

The biggest factor I've found for frame comfort has been the headtube diameter - even a 28.6mm steerer fork in a 1 1/2" headtube is uncomfortable. Same way that 55mm tires cannot fully account for the same large diameter headtube, despite what the marketing and personalities say.

I think most modern steel bikes are terrible because they are designed to meet ISO/CEN testing and nothing else. Velo Orange is a good example of the dark path. What happened to the pass hunter is a shame. The first two iterations were nice, light and responsive bikes that had fair compliance for mass production steel. The current version is heavy and may have the stiffest fork/headtube junction ever produced on a bike meant for pavement. It's an impressive design feat. The ride is, to be charitable, not very good.

[Mark McM]

Originally Posted by reuben

If I rode wearing a suit of armor, I'd need a COMPLETELY different kind of chamois.

Perhaps to understand the suit of armor analogy, you have to understand that for plate armor to work properly, the user actually uses a multi-layer system. Underneath the armor plate is worn a padded suit, which is just as important as the armor. While the armor plate prevent penetration and distributed impacts, the padded suit absorbed the shock and energy of hits. If a user wore only the armor plate and nothing underneath, they'd suffer the concussions from blows nearly as badly as without the armor plate. Imagine being hit on the head while wearing metal helmet with with no padding, and you get the idea.

In a bicycle, the frame is like the armor plate, in that it keeps the bike's shape under hits and blows and distributes the forces. But for the cushioning layer, the bicycle relies on the compliant components like the tires, saddle, handlebar tape, etc. In case you don't believe this, try riding a bike with solid tires, rigid steel saddle and no handlebar tape and see how comfortable it is.

[weisan]

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[martl]

Originally Posted by vincenz

And are there no things that humans can perceive and corroborate that cannot be measured simply with a number? Using a scientific approach to make a subjective judgment is flawed.

It is the purpose of science to find the laws behind the perception. There are many things still not fully researched/understood (ask the brilliant people at CERN or at NASA) but somehow I don't think strain of a comparably simple structure like a bicycle on a bumpy road is one of them.
The physics behind that are rather well known and proven.

Maybe you just are not as discerning then if you cannot tell a difference between frame materials. In that case, you can ride whatever and have it all feel the same. Kudos to that.

I owned and rode bikes made of oversized aluminum, lugged and tig welded steel, and a Moots over the years, even a battered Alan, but let's keep that one out . Some I liked better than others. All rode differently. None was more or less comfortable than the others due to the properties of the material used. I'm pretty sure I could tell a nice Veloflex tubular from a Vittoria Rally by the quality of the ride, though.

[Mark McM]

Originally Posted by benb

Also stuff like the features in a Specialized Roubaix or a Trek with the ISOSpeed beams... those all really break the rules around these kind of frame debates.

Absolutely. Specialized used to have their Zertz elastomer inserts imbedded in frames, but these mostly a joke. In order for the Zertz to absorb shock, the frame would have to flex enough to squish the Zertz. But the frame is so rigid that the Zertz inserts could never be compressed enough to absorb anything. Image a car suspension with a coil spring and a shock absorber in parallel. Now replace the spring with a solid rigid cylinder. Do you think that the shock absorber would be absorber much shock, now that it could no longer be compressed? That's kind of like how the Zertz inserts were.

Some bike manufacturers are finally now giving up on the charade that standard diamond frames provide any meaningful compliance and comfort, and when compliance is desired, are now building in pivots and "spring" members to provide meaningful deflections.