rpenmanparker 

Yes, but is that due to material or design, i.e. where the weight is placed on the fame?

In a very basic sense the specific stiffness (stiffness per unit density) of Al, Ti and steel are essentially equivalent, about 0.26 for the common engineering units. In other words steel is stiffer than titanium for the same part design, but if you make the weights the same, the stiffness equalizes. So if you had the identical bicycle design in terms of tubing diameters but just with different wall thicknesses, bikes from the three materials that weighed exactly the same would have very similar stiffness attributes.

But when you place materials in order of their ability to provide stiffness in the lightest weight embodiments you have Al>Ti>steel. The reason for this is that stiffness comes more from tube radius than from material. Stiffness is a cubic function of radius but only a direct function of weight. So large radius (diameter) tubes with thin walls will always provide the best weight-stiffness balance. However the tendency for denting is a direct function of the diameter/thickness ratio. Since Al is so light, its walls can be thicker than Ti, which can be thicker than steel all at the same weight. Hence you can make lighter aluminum frames that aren't at a high risk of denting. Ti is in between, and steel is the worst in this regard.

In short your contention is false. The a priori ability of the three popular bicycle metals to produce an optimally light and stiff frame as limited by tube strength and resistance to denting decreases in the order Al>Ti>steel. Any departure from that order that is anecdotally observed is due to a design fault, not the fundamental properties of the materials.

Jarrett2

That's fun on paper, but I'm talking about practical application. You are maintaining that Lynskey chose to make it that way? Meaning, they could have made a lighter, but stiffer frame but chose to make a heavier but more flexible frame? No offense, but I think Lynskey knows how to make a better titanium frame than you do.

rpenmanparker 

Meaning that light vs. stiff was not Lynskey's only consideration. As a bike designer he has his own ideas about how a bike should ride and feel. Those considerations are apparent in the history of aluminum frames. They went from noodles to brick outhouses and now back to very fine riding, very light designs. If Lynskey's bike rode in a way that you found too soft, it is because that is what he wanted it to do. On the other hand the tales of flexy steel bikes are legion. Any of us who have been doing this a long time have ridden one...or more. It isn't the material, it is the design when talking about these three metals.

If you want uber-stiff Ti, buy a very reasonably priced Everti Falcon. I had to sell mine, because it was just too damn stiff while only weighing 3.25 lb. I bet that is lighter than your Gunnar.

rpenmanparker 

No doubt, but did it ever occur to you that the better frame that Lynskey does indeed know how to make it not the one you prefer? I am not talking about good and bad when I say what is possible to do. I am talking about what are the limits within which each builder has the opportunity to work. What they come up with is their business...literally.

adrien

Wasn't your briefly owned Lynskey a Sportive? If so, um, yes. Sportive bikes tend to be built for comport over long distances, not outright stiffness. Something like a Helix is much more optimized to what you describe.

Jarrett2

Yeah, but it was probably a size 48 though

That question didn't make enough sense to decipher it.

I had the R240, which they say is their most popular frame. The Helix is stiffer and also considerably heavier. Light, flexy. Stiff, heavy. That sort of correlation was what I was talking about earlier.

rpenmanparker 

Size 54. Sure my question made sense. If I am not as good a bike designer as Lynskey is, what makes you think that you are? In other words, what makes you believe the bike you think is best is the same one he thinks is best? If you really believed that he is such a good bike designer and builder, shouldn't you just ride the 240 and be happy with it? After all he must know best, right? Uh, no, not quite, huh?

Also the 240 is not his most expensive frame. Why would he build it with the ultimate combination of stiffness and lightness. Doesn't he reserve that for something pricier? Isn't that how business works: the more features you want, the more you have to pay?

So how much does your steel frame weigh?

Jarrett2

lol, I hope you aren't getting upset, its just a discussion. You're starting to sound a little miffed with the nonsensical questions.

rpenmanparker 

Not at all. I am just trying to get you to recognize that not every bike was intended to be ideal for you. A Ti bike at a given weight that rides softer than you like doesn't mean that a stiffer one couldn't have been built at the same weight. And I am not saying that the guy who built it didn't know how to do better. I'm saying he built what he wanted to build according to his idea of what's right. The problem is it was just not what you wanted to buy. But that's fair. None of that says anything about ultimate relative stiffness and weight of the metals and bikes made from them.

rpenmanparker 

Oh, and you still haven't said how much your steel frame weighs.

Jarrett2

Thanks for clearing that up for me

rpenmanparker 

So Jarrett2, just asking, you aren't going to tell us what the Gunnar frame weighs?

Jarrett2

Gunnar can answer that one.

rpenmanparker 

Apparently he can't or won't. Correct me if I'm wrong. Is your frame the Sport. If so, I see the 54 cm size listed by a reviewer at 3.6 lb and also by another user at 1.65 kg which is just about exactly the same. Just a smidgen heavier than the R240. Different placement of the weight could easily make the difference in BB stiffness and road feel.

dr_lha

This is a constant source of frustration to me. Why do frame manufacturers act like weights of their products are such a top secret detail? When I asked earlier about the weight of typical Ti frames, I was not trying to make any point, it's because I literally have no idea how much a typical Ti frame weighs.

rpenmanparker 

Well, I have had two Ti road frames in size 54. One weighed 1475 g and the other is 1207. The lighter one is a much better ride.

Jarrett2

Likely because they are not that far off from each other as many like to think. If you are comparing to Reynolds 520, then titanium is going to be super light. But start comparing it to OX Platinum, S3, 953, etc. and all of the sudden the massive weight savings goes out the window.

For example, I suspect your Ritchey is similar in weight to a Lynskey R240 with the same groupset. But I bet if you rode both of them, you'd prefer the ride of the Ritchey.

dr_lha

OK, so lighter than steel generally, at least the two you owned. IIRC the lightest of lightweight steel frames are around 3lbs (1400g) with 3.5-4lbs (1600 to 1800g) being more typical for a high quality modern steel road bike (i.e. not touring) frame.

I'd certainly hope that'd be the case.

rpenmanparker 

You have no basis for that suspicion.

rpenmanparker 

My 1,207 g Ti frame is still a pound lighter than your Gunnar. ONE POUND! OX Platinum and all. Best riding bike I have ever been on. Go figure.

adrien

Seems to be getting a little snippy here. Jarret posted a photo of his built up Gunnar on a scale at the LBS. IIRC, it was about 18 pounds for a 56, which actually runs a little small and it's a compact frame. Perfectly respectable, and to his point, really nice for a good steel frame. Most of the custom frames I see run 17-20 fully build, depending on build kit, and especially the fork. I have a lugged steel bike with a lugged fork that comes in around 21 for the equivalent to a production 62.

I also have a ti bike that sits right around 17.5, ready to roll. It's notably stiffer than the steel bike. 58.5 TT, 57 ST, and that's with heavy pedals, garmin mount, bottle cages...

But also note -- this is a data set of one. This steel bike is heavier, and more flexible (and smoother and more comfortable and more versatile) than this ti bike (which is stiffer, faster, lighter). Pretty sure that's the case because they were built that way based on what I asked for. And I got it and am happy. Jarret thread below:

https://www.bikeforums.net/clydesdale...die-today.html

Jarrett2

k

adrie, it's actually a 58, but close enough. The $5800, full carbon Roubaix that was also 18 lbs in the pictures was the 56.

I'm sure if I would have spent the money on light components like those on the Roubaix, I could have gotten my steel 58 into the 17's.

When I was getting fitted for the bike, another guy walked up and told me he had bought a Gunnar Roadie as well in 54, but he went full Red and all the light goodies and his was 16 lbs. But like every other claim in this thread aside from mine, its not verified. We can throw around numbers on the Internet without evidence all day.

rpenmanparker 

There is no reason to doubt that claim. A good rule of thumb for a reasonably light build kit based on Red is about 10.5 lb in showroom condition or 11.3 lb they way I ride a bike (my pedals, cages, computer stuff). So assuming a carbon fork on the Roadie weighing 335 cut, that would be about 2000 g for the frame and fork or 4.4 lb. A quick sum gives you 15.8 lb for a road ready Gunnar outfitted that way.

My Romic steelie frame made from Reynolds 531 SL weighs 2550 g 5.6 lb with carbon fork and makes up into a 17.05 lb road-ready bike with Rival derailleurs and shifters. 16 lb for the Gunnar would be a snap. Even a pound less is not out of easy reach.

It isn't even hard enough to elicit doubt, much less a suggestion of mendacity.

Jarrett2

Hell, in that case, my bike weighs 15 lbs and my average speed on the MUP is 23mph

Jarrett2

Some things only have anecdotal evidence and that's fine, you take it with a grain of salt.

But when people state things that could be backed up with statistical evidence and don't... it makes one wonder.

And your attachments aren't working at this point. "Invalid Attachment specified."