Me too. I have two steel bikes but no titanium. I have a Firefly frame on order but it will take another 13 months to get it (unbelievable!). Then I'll know.

I think you missed my point, which is that given the same frame geometry, dimensions, and tubing chosen to make the frame equally stiff, a frame made of either 3Al-2.5V or 6Al-4V titanium and a similar frame made of Reynolds 953 stainless steel will weigh essentially the same. It doesn't matter what the geometry and frame style are, if they're the same they'll weigh pretty much the same.

Most all of you materials engineers here already know this stuff, but let's take a minute to review it.

Titanium alloys and steel alloys differ greatly in physical properties.

Ti 3Al-2.5V has a density of 4.48 grams per cubic centimeter
Ti 6Al-4V has a density of 4.43 grams per cubic centimeter
Reynolds 953 has a density of 7.8 grams per centimeter, or a little less than twice that of titanium

Ti 3Al-2.5V has a Young's modulus, or stiffness (E) of 100 GPa
Ti 6Al-4V has a Young's modulus, or stiffness (E) of 113.8 GPa
Reynolds 953 has a Young's modulus, or stiffness (E) of 207 GPa, or about twice that of titanium

Ti 3Al-2.5V has an Ultimate Tensile Strength (UTS) of 620 MPa
Ti 6Al-4V has an Ultimate Tensile Strength (UTS) of 950 MPa
Reynolds 953 has an Ultimate Tensile Strength (UTS) of 2,000 MPa, or more than twice the UTS of titanium

Ti 3Al-2.5V has a Yield Strength (YS) of 500 MPa
Ti 6Al-4V has a Yield Strength (YS) of 880 MPa
Reynolds 953 a Yield Strength (YS) of 1,800 MPa, or three times the YS of 3Al-2.5V and more than twice the YS of 6Al-4V

Ti 3Al-2.5V has a Rockwell Hardness of 24 HRc
Ti 6Al-4V has a Rockwell Hardness of 36 HRc
Reynolds 953 has a Rockwell Hardness of 44 HRc, significantly higher than titanium

Ti 3Al-2.5V has an elongation (measure of brittleness/ductility) of 15%
Ti 6Al-4V has an elongation (measure of brittleness/ductility) of 14%
Reynolds 953 has an elongation (measure of brittleness/ductility) of 14%, so Ti and 953 all are relatively ductile (they bend rather than break when the yield strength is exceeded). In comparison, carbon fiber composites have elongation in the 2% - 5% range and are more brittle.

So what does all of this mean?

Density: Steel, with almost twice the density of titanium, is clearly density challenged. Density is steel's Achilles heel.

Young's Modulus: Reynolds 953 steel is about twice as stiff as titanium.

Ultimate Tensile Strength and Yield Strength: Reynolds 953 steel is more than twice as strong as titanium.

Hardness: gouge and dent resistance for Reynolds 953 steel is significantly greater than titanium for a given tube wall thickness.

Brittleness/Ductility: Titanium and Reynolds 953 are similarly ductile.

Even though a given volume of titanium material weighs about half of what steel weighs (all steels have virtually the same density), its greater strength means that Reynolds 953 steel tubing can be drawn with thinner walls (as low as 0.3mm in the top tube, for example). The thinner walls mean less weight; titanium, because of its lower strength and Young's Modulus has to have thicker walled tubing which means added material and weight. But wait, thinner walls mean flexier, right? Yes, but because the Young's Modulus (stiffness) is twice titanium's and the tubing diameter can be increased to make it even stiffer with only minimal added weight, the net result is that frames made of Reynolds 953 (or other new high strength steel alloys) are very competitive with titanium frames similar in size, geometry, and stiffness.

http://i32.photobucket.com/albums/d7...onChartxsm.jpg

There's a great series of articles called Metallurgy for Cyclists by Scot Nicol, president of Ibis, that's an excellent read, even though it was originally circa 1994 (long before 953 was introduced). It's a great way to gain a fundamental understanding of materials used to make bicycle frames.

Never mind once you start varying tires (20 tubulars, 25 clinchers, 28 clinchers tubeless...)

After 30 years of riding primarily one steel bike, I have rust everywhere. I found a cheap Litespeed 26" MTB frame that I built as a 700c Road bike. Probably a bit stiffer than the equivalent road frame.

The two bikes are very different in fit, but I wouldn't say the "ride" is that different from one to the other with the exception of the lower bars on the Litespeed build.

However, the Titanium bike does make a nice "rain bike" for the winter. Just wipe off and no rust. Hopefully in the next month or two, I'll do a second budget Litespeed build, this time with a road frame for the base.

Your material property comparison of Ti and Reynolds 953 was informative.

To put a finer point on what you wrote above, Ti has a lower modulus of elasticity...its more flexible than steel. Ti is also lighter based upon volume of material. This proportionality allows a frame designer to use a greater volume of Ti compared to steel for comparable weight and by adjustment to tube cross section and wall thickness, the same level of stiffness can be achieved compared to steel at close to the same weight. I believe in general depending on frame geometry that a Ti bike may in fact end up marginally lighter than a Steel bike for the same level of stiffness but I do believe what you wrote is pretty accurate and what I wrote explains why.

And there is a corollary with Aluminum. Many that ride Al bikes...not so much any more....notice immediately how stiff they are. This has changed with hydroforming and more asymmetric Al tube sections. This is Aluminum's ace in the hole compared to Steel and Ti and why for me, Aluminum has moved to the front of the class for metal bikes...and of course the big brands agree with this. Almost no Ti or Steel bikes produced by top brand makers. But in the case of Al, its material properties belie how the bike ends up feeling. As it turns out, Al by a fair margin is the most flexible metal for bikes. And yet Al bikes are considered among the stiffness...so why? The reason is Al has a lower density compared to Ti and Steel as well. So a greater volume and larger tubing cross section can be utilized to gain the overall same strength as Ti and Steel. To make Al behave with the equivalent strength of Ti and Steel since Al is a relatively weak material, a greater volume of Al has to be used. This greater volume of Al is what gives an Al bike its stiffness. The reason why more Al can be used to gain stiffness and strength as Al is low on both metrics...is because Aluminum is so light weight.

The thing that has moved Al to the front of the class isn't its material properties. The Ti versus Steel comparison proves that each material can be made close to the same performance level...stiffness and weight for a bike frame and yet their material properties are notably different. Same thing with Aluminum as it turns out...again very different material properties...but with one major difference...because Al is so natively flexible and relatively weak, it can be made to perform well because its tube sections can be formed with greater asymmetry than either Steel or Ti which can't be molded as effectively. Al bikes can me made to look similar to carbon bikes which are molded of course whereas Ti and and Steel can not. A the end of the day...yes material properties matter but there are some relatively extreme differences. It is the forming difference that makes Al stand out...Aluminum can by hydroformed because of its lower yield strength compared to Ti and Steel.

I hear you and understand what you said. Let's agree that strength isn't the issue that affects bike feel. It is stiffness. And stiffness is available in spades for any of the materials we are talking about by utilizing the cubic relationship to tube radius, i.e. making the tube bigger around. But to keep the weight down, the extra circumference has to come out of the wall thickness. Isn't the limiting factor the tubing gauge, the dentability factor? And for lighter, more flexible materials, doesn't the greater wall thickness work to prevent denting better than in steel, so that bigger radius can be used to overcome the stiffness difference between Ti and steel and yet the Ti can still be lighter, because the walls can be thicker but still lighter. Steel can't be made as thin as needed to overcome the weight handicap due to dentability.

Ti is easier than steel to shape as well, and the best Ti bikes generally have more tube shaping than steel ones do. The shaping also provides disproportionate stiffness and can give Ti a weight advantage. The lone exception these days would seem to be the Breezer Venturi which is hydroformed steel, but I don't see it winning the weight war either.

Everything I said above is even more applicable to Al as Campag4life stated.

Let me know if my rudimentary understanding is incorrect.

Color bar graphs for the win.

Thanks for all of the input so far.

I understand that titanium and steel can be made to give any ride quality you want. My dilemma is that I have Reynolds 853 steel bike that gives me the ride quality I want. I'm just not sure how to convey that to a builder.

I have a size size 61 Jamis Eclipse where the frame looks like this:

http://www.roadbikereview.com/review...9_eclipsee.jpg

I'm trying to figure what size of Titanium tubing would equate to this bike's Reynolds 853 ride quality, but give the lighter weight and long lasting qualities of Ti.

Is there a way to calculate, if my Reynolds 853 tubing is this big around, then that means I need this size of equivalent tubing in Ti to build something similar?

These kind of material comparison threads are sooo repetitious and really a manifestation of how mind numbingly backward the bike industry has been in it's adoption of state-of-the-art engineering practices. Had bike makers known how to use aluminum like the folks that designed P-51's in the 1940's, Apollo in 1960's, Tomcats, Falcons, and Eagles in the 1970's-80's, and practically every high performance automobile across the same time span, today's misconceptions about aluminum as a bike frame material would have never happened. Only composites beat aluminum as a frame material when the performance criteria are low weight and structure dynamics. In biking, steel and titanium are plenty good enough though because of course "it's the motor" that matters most by a huge margin.

The questions you are asking are fair, but unrealistic and way outside your purview. You can't determine an equivalence between the materials on paper and expect a builder to translate it to the bike you want. There are just too many variables and that is not how custom bike building works. Your best bet, if you insist on custom, would be to let the builder ride your bike and then do his best to recreate in Ti what he felt.

As I have said many times on the 41, your predicament is exactly why stock bikes have an advantage over custom. You can ride stock samples until you find what you want. With even the best of custom builders it is a crap shoot. He may understand your wants and needs, but he may not. He may know how to translate what you say (or what he feels in your bike), but then again, he may not. He may get close if not perfect, but is that good enough? Then when you get the final product, you are stuck with it for better or worse.

If I were you, I would find a dealer that actually stocks a reputable Ti bike line like Seven, Litespeed, or Lynskey. Drive a good distance if you need to get to such a dealer. Test ride your ass off until you find the bike you like best, and then buy it. The custom route is a recipe for disappointment at least as likely as it is for satisfaction.

I wish I could offer more but this is all I've got.....I had a TI LeMond and it was fine. I currently have a newer Guru Sidero, steel size 55. It weighs 16 Lbs. 12 Oz w/o pedals or anything else. Oh, it has Ksyrium Elite wheels and (mostly) SRAM Red group. I love this bike but I can't really tell you why or if it rides better than any other material. I do think a custom steel bike or off the shelf for that matter will cost less than TI. I'd just try whatever I could get my hands on and see if it makes a difference to you. My guess is you will go with whatever fits you better. And, that's as good as anything.

What dealer carries numerous, built Ti bikes? I've never even seen one in all of the stores I've been to.

An experienced framebuilder should be able to build a bike for you in any material that will essentially duplicate the ride quality of your Jamis, and also provide a reasonably accurate estimate of what it will weigh.

The tubing diameter, wall thickness and butting profile chosen to duplicate the ride of your Jamis in whichever material you decide to use will depend on your height, weight, and power output. It's these tubing parameters that will, to a great extent, determine the weight of the frame.

The main reason early aluminum frames were overly stiff is because they were overbuilt to compensate for aluminum's lack of Fatigue Limit | Wikipedia. The stiffness limited the amplitude of stress cycles.

When it's painted, I prefer the classic look of steel tubing. All the Ti bikes I've seen have slightly fat tubes, and I don't like that.

Also I don't personally like the brushed Ti look. What I'm saying is, "prettier" is really subjective. Of course. :)

Ti bikes are harder to find today but I did exactly that several years ago. I live in a metro area where there are many dealers so my experience might be different. But if you are thinking about spending a lot of money, it's worth the trip.

You're trying too hard. A good frame builder will ask you lots of questions in order to determine what you're looking for. If you have a frame you like, they'll look at the geometry and construction. Someone with enough design experience will be able to look at a frame design and have a pretty good intuitive feel for how it rides.

Waste of time. Even if you knew how to calculate this, tubes are not available in infinite varieties. Builders have certain types and sizes to choose from and work within those constraints mixing and matching tubes and tweaking geometry to achieve their design goals. Builders who are good at this (either by science or craft or both) succeed and build reputation. Builders who aren't don't remain builders for long.

If you want to do custom, forget about materials, tube sizes, weight, etc. and focus on choosing your frame builder. Let the builder explain how he/she will design the frame to meet your goals. Let the builder explain the difference between steel and Ti for their frames. Get reviews from past customers (either through referrals or seek them out on the web). Most builders have decades of experience and are way more knowledgeable than even the most savvy customer. The more freedom you give the builder (i.e. the more you trust them to make decisions for you) the better chance you have of getting something you'll be happy with.

,

If you formulate your precise requirements, budget and timeline and communicate them to a reputable framebuilder they will do the materials planning to meet your requirements.
It's what they do for a living, some are better at it than others: Caveat Emptor.

If you plan on telling a builder what tube diameters and wall thickness to use for your custom frameset you will be replacing expert experience w/ amateur guesswork: Caveat Abecedarian.

-Bandera

fify

unless you have some odd body proportion, there is no economic reasons for going the custom frame building route for either steel or ti.

Thanks guys. I'm just going to look into Lynskey's and Litespeed's stock size models. The custom build thing seems too much for me at this point. Maybe some time down the road.

Your coming to the right conclusion even though there is no reason to spend the jack for a Litespeed when a Specialized Allez or CAAD 12 is out there..either will likely provide as good if not better ride...I say better...greater stiffness and close to the same weight as a Litespped or Lynskey. To me Ti is becoming more passé because designers can't form the tubes like Al.

As to geometry, good that you smelled the coffee. Unless you are 4 standard deviations to left or right of height median and only 1% of the population is, you don't need a custom geometry. It is almost impossible to get a custom geometry frame to have equivalent ride and performance qualities of a more mainstream common size. This is because custom builders don't have a computer program that can crush best tubing sections and thickness. Doesn't exist. Big brand guys can computer model more mainstream geometries but they then follow up with prototyping of each size with lots of road load data acquisition and further tweaking. Computer modeling isn't perfect...a facsimile. No boutique builder has this technology or data base. They do it with smoke and mirrors and as a result, that is what you end up with.

Yeah... I know everyone has experiences and opinions on frame material. I've developed my own as well. I'll just say that after owning a hydroformed aluminum Specialized Secteur, I couldn't get rid of it fast enough once I started riding on rough country roads. My carbon Specialized Roubaix was definitely a step up in feel from the aluminum Secteur and one that I was fine with... until I rode a steel bike. Now the Roubaix is for sale as I don't want anything but steel.

That said, when I talk to builders they unanimously say that if I like steel, I'll love titanium. So I'm starting to look down that road to see if I agree with them or not. The idea of shaving a couple of pounds off the bike and never having to worry about paint or rust is very interesting to me. I'm also finding that getting into a entry level titanium bike isn't much more expensive that buying a mid level steel bike, if at all.

IMHO you can't go wrong with either Lynskey or Litespeed. I'd try to stick with threaded British (1.370" x 24 tpi) BB shells though.

You and I do so agree on this. I am continually amazed by the nearly unanimous belief that a custom builder is going to get a bike just right by guess and by golly.

Thanks. That's something I was wondering about. What's the upside to the threaded British BB? Are there downsides?