|Why is steel not 'popular'||Rob11966|
Sep 26, 2003 3:28 PM
|I have a custom built stell frame (lugless). It's light, the bike is 8.6kg all up and that's without any special attempts to feather it up. The frame is beautifully finished, will last forever, the ride is great and it was cheaper (slightly) than a good quality alloy frame. So why are most of the commercially available frames aluminium and why do almost all of the pro's ride aluminium or titanium. Is aluminium so popular because of marketing, cost of production or the percieved weight savings? To ask the question another way, why is steel unpopular? I know people worry about rust but really this is not a problem with a bit of fish oil on the inside. We all know someone who has been riding some old steel clunker for 25 years without any rust issue. Overall I chose steel because of the advantages that I percieved, great ride, wide choice of tubes, long fatigue life and a weight penalty of only a couple of hundred grams. Cost was not my issue. BTW, I understand that there are several high end steel frames around but not many. What gives?|
|Two reasons - price and weight||Kerry Irons|
Sep 26, 2003 4:40 PM
|Aluminum makes a cheap and light frame compared to steel. We can talk about whether it makes a better frame, but cheap and light are all that you need to gain market share. Many cyclists, including freqent visitors to this board, seem to think that all frames are pretty much the same except that some weigh more and some cost more. You'll hear comments like "I can get an XXX frame for $$$, so why pay more?" All the points you raise are correct, but with a "new bike every 3-5 years" mindset among many riders and people willing to accept that materials have inherent properties ("Al makes a stiff frame, steel and Ti are flexy"), it's not too surprising that steel has lost its once-dominant place.|
|Higher profits with Aluminum||MR_GRUMPY|
Sep 26, 2003 5:12 PM
|Cheaper to make, not cheaper to sell.
With silly light Aluminum frames at 2 1/2 pounds and silly light steel frames at 3 pounds, there isn't much difference unless you are at the top of your game, along with 150 other riders. 99% of off the shelf bikes sold in shops are Aluminum, because of the profit thing. When you start talking about frameset-kit sales, Aluminum sales are still tops, but steel and Ti do take a good share.
|Longer life for your kidneys...||lyleseven|
Sep 26, 2003 6:45 PM
|Steel can be built (custom builders) to match, or very closely approach the stiffness of aluminum, but with slightly more weight. As Mr. Grumpy said, unless you are at the top of your game, you probably won't notice any significant difference. If you want longevity for your kidneys, stick with steel or Ti!|
|Longer life for your kidneys...||Woof the dog|
Sep 26, 2003 10:28 PM
|What do you mean longevity of your kidneys. surely you are not saying that steel rides nicer than al. Cause if you are, i think you may be not completely correct. I hear and agree that these days al. frames ride just as nice as steel frames. Its all design and wall thickness/diamter anyway, right?
Woof the cock, i mean dog.
|Longer life for your kidneys...||lyleseven|
Sep 27, 2003 8:18 AM
|I am saying that aluminum has a harsher ride. The tests performed to compare steel and aluminum bare this out. Sure, you can add carbon fiber seat stays and forks and it helps a lot to dampen the harshness of aluminum. If you start getting thicker walled aluminum you somewhat defeat the purpose of the weight difference. Steel is definitely a more comfortable frame, all other things being equal.|
|Well, that's just completely wrong||Kerry Irons|
Sep 27, 2003 3:47 PM
|25 years ago, everyone would have said to get an aluminum bike to smooth out the rough stuff. They had a reputation as being soft and compliant. Did somebody mess with the periodic table in the mean time to make Al a "harsh" metal? No, as the other poster said, it's all about design. Within the desirable parameters of a bike frame, you can design the same ride with steel, Al, or Ti (can't get that metal feel with CF, and can't get that damp feel with metal). The market has gone to stiff Al bikes, but only because of large tube diameters. Al is a cheap way to make a light bike, and since people will pay more to save 100 gm, Al will beat steel at that game. It is COMPLETELY WRONG to state that Al has a harsher ride.|
|It's not wrong, its simple metallurgical science...||lyleseven|
Sep 27, 2003 8:45 PM
|You obviously haven't read the metallurgic studies that have been out for years on the difference between Al and Steel. There is what is known as a trampoline factor in aluminum which is much higher than in steel. Basically, it has to do with the metal and the porosity. I am not saying that much of that can't be dampened by frame design. I am simply saying that other things being equal, Aluminum is inherently harsher. Design two identical bikes, one out of Aluminum and one out of steel and you will notice the difference, assuming the tubes are of the same thickness, etc.|
Sep 28, 2003 4:11 PM
|True: different alloys of the same material have different damping factors. Just do a search for grey & white cast iron. They both have different damping factors.
It has **nothing** to do with porosity! Metals have extremely little or zero porosity. Unless it is a casting, and then it only has "voids", not porosity.
I HAVE SPOKEN!!
|You completely miss the point||Kerry Irons|
Sep 28, 2003 5:14 PM
|No one in their right mind would ever "design two identical bikes, one out of aluminum and one out of steel. . ." Either the steel bike would have preposterously thick tube walls, rendering it extremely heavy and VERY harsh, or the aluminum bike would be a noodle with tube walls too thin to withstand the slightest impact. Your orginal claim was that Al frames were harsh by definition. WRONG, WRONG, WRONG! It is how you design the frame, not the material. Full stop. Of course Al, Ti, and steel have different properties, and any decent designer takes that into account. The trampoline factor is just another physical property to consider in proper design. You say that "I am not saying that much of that can't be dampened by frame design" but that is exactly what you claimed originally - Al frames are harsh. Which is it?|
|You completely miss the point||lyleseven|
Sep 29, 2003 6:51 PM
|You can dampen some of the harshness out of the aluminum by the frame design. It's trampoline effect is greater than steel i.e. it bounces more with same impact. This is because it is a lighter material and the nature of its metallurgical makeup.|
|Well, that's just completely wrong||MShaw|
Sep 29, 2003 10:06 AM
|25 years ago there were about three guys making AL frames: Cannondale, Klein, and Vitus. I owned a C-dale Crit frame. It was harsh. The Vitus was always a noodle.
American cyclists didn't have too much knowledge of the Vitus frames, so all AL rode harshly.
The Euros didn't know what a C-dale was, so all the AL frames rode like noodles.
Now that we're 25 years down the road, generalizations like "all AL frames ride harsh" isn't true any more than "all Frenchmen are cowards."
If you haven't ridden al AL frame in a lot of years, you'll be pleasantly surprised.
|My S-Works rides softer than my Bontrager Road Lite.||MShaw|
Sep 29, 2003 10:00 AM
|And the Bontrager is a steel bike. They've come a loooooong way in Al frameset design over the years!
|My S-Works rides softer than my Bontrager Road Lite.||lyleseven|
Sep 29, 2003 6:54 PM
|No question about the advances in aluminum by the way they design them and also mate them to carbon fiber. But an all aluminum bike will ride harsher than one with carbon forks, seatstays, etc. I own an aluminum bike made within past 5 years. it is stiff and fast, but not the one I chose to ride all day long, like a Ti or steel bike, which I also own.|
|Longer life for your kidneys? Quality construction is the key!||10speedfiend|
Sep 28, 2003 2:29 AM
|My Specialized S-Works Columbus AL rides way smoother than My custom Reynolds 835 frame does with the same wheels. Steel Does not guarantee a great ride! Construction and proper tube selection whatever the material,is what makes a great ride. I dont care for the radical butting of lightweight steel tubing. The stuff dents way too easy!A rock kicked up to the middle of the down tube = dent. Handelbars to the TT = dent. Chip the paint = rust. Want a better ride? go to 700X25cc tires.
|Marketing and the Trend Factor, IMO||Cory|
Sep 26, 2003 7:33 PM
|I have three steel frames, from a relatively new Atlantis to a 20-year-old Trek that's a singlespeed now, and I don't have any complaints about any of them. They're light enough, comfortable and (if the Trek's any indication) should last forever.
They ARE a pound or so heavier than friends' aluminum and titanium bikes (to be fair, mine are 64s and they ride 56-58cm), and that scares some people off. Manufacturers hammer that weight issue so hard that not many people really think about it. A pound may be 30 percent of the weight of a FRAME, but it's only 0.5 percent of the bike/rider package, so it's not significant for everyday riding. And I'm long past the point of needing a new bike every few years just to keep up. I plan to ride the Atlantis, friction barcons and all, as long as I can get a leg over it.
|shaped & o/s tubing||powergyoza|
Sep 26, 2003 11:40 PM
|With all the bikes that use shaped & oversized tubesets, I'd imagine that it wouldn't make sense to use steel. You'd prolly wouldn't be able to make the wall thickness narrow enough to make up for all the extra material being used.|
|Two points to consider:||Spunout|
Sep 27, 2003 3:24 AM
|Shaped Tubes: Pinarello Opera. Custom drawn 16.5. Shaping tubes is thought to customize the compliance and stiffness. Which begs the question, why are you using the wrong tubing material then? See next item for a completely round tubed (even the stays) bike. If you use the right materials in the right specs, a round tube is stronger than an octular/lobular/clubular whatever.
OS Tubes: Pegoretti Marcelo in EOM 16.5. Still much tougher than anything in aluminum, plus steel just bends where AL will crack.
|Steel bends and AL cracks? You are incorrect!||10speedfiend|
Sep 28, 2003 2:58 AM
|Steel used in frame construction is not re-bar quality, just as the Al used in frames is not beer can quality. Align the molecules and shape the tubes of either material and you have a great riding bike. But to say an Al bike breaks and steel bends is wrong.
Here is the test results.
|Round tubes work perfectly......||Rusty Coggs|
Sep 27, 2003 5:17 AM
|Alot of shaping is just more marketing. Steel can be manipulated too without weight penalty.|
|marketplace is weight obsessed||DaveG|
Sep 27, 2003 10:58 AM
|Marketing has convinced most of us that our bikes have to be as light as possible. Cheapest way to do that is with Al. I have 3 steel bikes now. I likely will continue to stick with steel. However, the number of reasonably priced steel frames is drying up fast.|
|"Steel" = "Old"||dgangi|
Sep 27, 2003 11:30 AM
|The demise of steel as a build material for bike frames is very simple -- it is perceived by the buying public as "old fashioned" technology. Yesteryear. Stuck in the past. Therefore, not "fashionable".
My mom's 3 speed bike from the 1950's was steel. My first Schwinn Fastback with the banana seat was steel. My old Schwinn Varsity from 1980 was steel. My first BMX bike from the early 80's was steel. Huffy's at Wal-Mart are made of steel.
See anything in common here? And so does the rest of the world. Steel is what you rode as a kid; what your mom or dad rode; what your grandparents rode; what cheap bikes are made out of today. Therefore, steel is passe...plain and simple.
That doesn't mean a steel bike is not a good bike. Many bike enthusiasts know that nothing out there beats the ride of a steel bike. But perception is everything in the marketplace, and that's why steel is doomed.
|"Steel" = holding its own!||lyleseven|
Sep 27, 2003 8:52 PM
|I think your prognosis is wrong. Steel is still a very strong percentage of the market and most custom builders use it (and titanium), not aluminum. Aluminum grabbed a big share for several years and then tapered off to some degree. It has the edge on weight and that propelled its popularity along with its stiffness for climbing,etc.|
|"Steel" = dying breed||dgangi|
Sep 27, 2003 10:03 PM
|Strong percentage of what market? Wal-Mart bikes? Or bike-shop quality bikes?
I've been through at leat 10 bike shops over the past month. Of all the bikes that I saw in the stores, I would say that <5% were steel. In fact, more bikes were carbon than steel.
Maybe steel is still a decent percentage of the "custom build" market, but that market percentage is dinky compared to the bigger boys.
Trek, Specialized, K2, Giant, Cannondale (Felt, Fuji, on and on) - none of these companies make bikes from steel. I will bet that 10 years ago many of these companies made steel bikes. And since these "big boys" make up at least 80% of the "LBS-quality" segment (not counting Huffy, Wal-Mart bikes), what percentage is left for steel bikes? Very little.
Again, I am not knocking steel as a reputable and worthy build material. I fully understand the benefits of steel - especially when it comes to ride quality. But now that aluminum frames are coming with carbon seat stays to smooth out the ride -- it's only a matter of time before steel is a total rarity. It's already vanished from the mountain bike world (unless you consider Huffy's).
|where have you been?||moschika|
Sep 27, 2003 10:40 PM
|most target, walmart bikes, etc are aluminum that i've seen. other then the kids bmx types bike everything else on the shelf is Al.
Trek's other half, Lemond come in steel still. as does specialized. c'dales never came in anything other then Al. don't know about the others.
my mtb isn't a huffy or any other off the shelf brand and it's steel. most, if not all custom american builders offer steel frames and bikes for either road or mtb. bianchi still makes steel bikes.
there is still plenty of a market for steel.
|where have you been?||dgangi|
Sep 28, 2003 7:59 AM
|I did not realize that steel was not being used on Huffy's anymore (it's not like I shop in the bike section at the local Target or sporting goods warehouse). That means steel's market share overall is even less than I thought.
So what's left? I still claim it is a shrinking part of the road bike market. And with advances in technology, steel will be gone at some point (or a pure rarity). Trek, Specialized, and all of the other "big boys" are pouring their R&D into aluminum and carbon, not steel. There will always be boutique brands that build steel bikes, but that market segment is so tiny.
BTW - what mountain bike are you riding that is made from steel? Nothing from the last decade, unless it is a hand-made hardtail from Salsa or one of the very small boutique brands.
|where have you been?||moschika|
Sep 29, 2003 9:12 PM
|my steel hardtail mtb is from a small custom builder. so i am part of that small market segment. btw, these small builders don't seem to be hurting too much either. there are still plenty of wait times to get your bike after everyone in line ahead of you gets theirs.
until recently bianchi was making a good steel mtb. but i see that they aren't any more. but i would hardly say that steel bikes will disappear any more then any other material. there are still advances in steel tubing. lighter, stronger, blah, blah, blah. it seems to be cyclical in what's popular. the advantages and disadvantages in one material over another for most people is negligable.
|disagree, not many steel bikes||laffeaux|
Sep 29, 2003 2:06 PM
|A couple of examples that you use...
Lemond - check out their 2004 line up. There's steel there, but most of the highend bikes now came as 1/2 steel and 1/2 carbon fiber.
mountian bikes - when was the last time you tried to buy a steel MTB? Unless you go custom your choices are VERY limited. There are a few manufactures that still use steel, but I'd guess it's sifnificantly less that 5% of the bikes sold.
I own mostly steel bikes (although I do have two AL MTBs). I prefer steel, although it has anything to do with ride quality (the AL bikes that I have ride as well as a steel bike). It has more to do with tradition. Even though I'm a fan of steel, to think that it's more than an "also ran" at this point is ignoring the sales figures.
|"Steel" = dying breed||al0|
Sep 28, 2003 3:59 AM
|Your statement is wrong, for example, Specialized still to produce steel bikes, all bikes in Allez series for 2004have Cr-Mo counterparts. Cneck on their site|
|"Steel" = dying breed||lyleseven|
Sep 28, 2003 8:40 AM
|Steel and Ti make up more than 80% of custom market. You just don't see custom aluminum being built. it is all prefab. I have had aluminum (good quaiity, carbon forks, etc), Ti and steel. The manufacturers you mention are all of the mass producers, many of which have those aluminum bikes stamped out in Taiwan. The insignificant weight difference didn't make up for the ride deficits. I'm not saying there are not good aluminum bikes, but 90% of them don't ride as well as steel or Ti.|
|"Steel" = dying breed||weatherx|
Sep 28, 2003 12:22 PM
|check specialized and fuji websites. there're also marin, jamis, etc.|
|Sounds more like a case of perception=reality in your case||Lone Gunman|
Sep 28, 2003 3:42 PM
|If you want a steel frame these days all you have to do is look around, what is disappearing in the steel frame market is lugged steel frames, need to look harder for them. There are sooo many choices in frames these days that the perception that steel is fading away is not reality, a consumer has more choices. You want steel (example) go to GVHbikes.com website and look at his offerings in steel. Viner, Landshark, Cinelli lugged, Basso, Pegoretti.|
|Sounds more like a case of perception=reality in your case||dgangi|
Sep 28, 2003 6:53 PM
|Those brands you mention are all very high-end, custom brands. The "average" rider has never heard of them. And their market share is dinky compared to the mass-produced aluminum bikes out there (probably <5%).
I am not saying steel is dead. All I am saying is this -- go to any bike shop in the USA and look at what they have in stock: $500 - $3000 bikes in aluminum. They might have a few steel bikes. Maybe. They also might have some carbon bikes (especially the Trek dealers).
I just shopped around for a new road bike and went through a dozen dealers in Phoenix (mostly the usual stuff - Trek, Specialized, Giant, Felt, etc). I asked them all about frame material and they carried primarily aluminum. I asked about steel and carbon and the majority of them said "yeah, we can *get* those but we don't usually carry them" (Trek guys being an exception because their high end bikes are all carbon). Only a few stores had a Salsa or other steel frame.
And if you look at where the majority of the R&D is going -- it's aluminum and carbon (some titanium). Check the website of any major brand and they all brag about "matrix this" and "matrix that" (for aluminum) and "carbon processes that make theirs better" (for carbon).
Steel is a great material. I like steel. It has such a comliant ride. But it's biggest downfall is weight, and once they can make an aluminum or carbon bike feel like steel at half the weight, then what would be the reason for keeping steel around?
|Sounds more like a case of perception=reality in your case||koala|
Sep 29, 2003 2:09 AM
|Steels biggest downfall is weight? My new compact foco frame is 3.25 lbs with paint and bottle bolts in a 55. My friends 54 straight guage ti frame is 2 ounces heavier. Butted ti is a little lighter but we are talking about less than your average body weight fluctuation day to day. Sure carbon is lighter but once again its not a big percentage of total bike and rider weight. I bought yet another steel frame due to road feel and price point in custom. Someday I will own something more exotic but for the money, custom steel from American builders kicks tail. I raced on aluminum years ago and it was fine, too, I just think a well designed foco has a great combo of ride, price and tunability thats hard to beat for the money. Carl Strong tunes his ti frames to ride like steel, in fact.|
|Sounds more like a case of perception=reality in your case||lyleseven|
Sep 29, 2003 6:58 PM
|I agree. I have two Mikkelsen custom frames ($800 each) and they ride like silk. They weigh almost 3/4 pound more than my Aluminum bike, but I hardly ride the Al anymore due to difference in comfort on long rides.|
|maybe shop owners have the same biases about steel.||rufus|
Sep 29, 2003 7:59 AM
|their primary goal is to sell stuff. so they only order in stuff that they can sell. either they, or their customers, have the same biases about steel that you do: that's it's a vanishing material, outdated, old technology, heavy, will rust, that they have to push the latest and greatest, etc. rather than take the time to educate their customers about the good points of steel, or double their inventory to carry both steel and aluminum models, they stick to the tried and true aluminum when making out their orders for the season. they know they can sell these with little effort.
so then people like you go to bike shops and see only aluminum models, and get the impression that that's all that's available these days, that steel is dead. it's a self-perpetuating cycle, when the reality is a bit different. specialized, for example, re-introduced steel allez models for 2003 after several years offering only aluminum models. the only difference was that their past steel bikes had been lugged, and these new models were tig welded. whether their dealers choose to stock the steel models, or stick to aluminum probably has a lot to do with the dealer size and free cash available to spend. if few dealers stock the steel models, then they'll sell less, as customers will only buy what's available. if steel bikes were there on the sales floor to be ridden, their sales would probably be better.
there is also the factor of the sales agreements dealers have with the manufacturers. the maker tells the dealer that they have to buy a certain amount of product from them. maybe if a dealer wants to buy some steel bikes, like 10 or 15, but the maker requires that he buy a certain number, like 50, and the dealer isn't sure if he'll be able to sell them all, he decides not to buy any instead, and allocates his resources elsewhere, like into more aluminum bikes.
|maybe shop owners have the same biases about steel.||lyleseven|
Sep 29, 2003 7:02 PM
|It really depends on the kind of bike shop you are talking about. If you go to a custom shop that builds from a number of custom manufacturers, you see a ton of steel bikes and titanium bikes and very few aluminum bikes. If you go to a more generic shop that carries the big names like Cannondale, Trek, Specialized, your choices are really limited and the novice customer will listen to the sales pitch of these shops that have to sell what they can carry. The custom shops give you a wide variety of choices in materials. I don't know any custom aluminum bikes where you can spec the tubes, angles, etc., like in steel. Are there any?|
|I wish I could agree but||DaveG|
Sep 28, 2003 4:06 AM
|Steel is certainly still available at the elite/custom end of the cost scale but is becoming increasingly rare on mid-price production bikes. If you are in the $1K-$2K price range your options are pretty limited. As a percent of the market, I imagine steel is pretty low.|
|My friend Chris has an AL Huffy and it is STILL heavy! nm||MShaw|
Sep 29, 2003 10:09 AM
|re: Why is steel not 'popular'||al0|
Sep 28, 2003 3:52 AM
|It was a link posted in "general discussion" few days ago to article that compares fatigue life of different light bike frames on stress test machine under cyclic load. IT appears that steel frames crack first! The best result of steel frame was worse than the worst result for aluminium one. The scale was as follow (from worst to best) steel|
|Porches are steel||peter in NVA|
Sep 28, 2003 4:05 PM
|I think its interesting that someone who buys a Carbon bike because steel seems low tech wouldn't worry that their dream car was a steel Porsche. Corrision warranties imply steel rusts, and people just accept that for cars.
I love my steel cyclo-cross bike, but admit its high maintenance. The paint chips all the time down to bare metal and I have to touch it up weekly. It will rust in no time if I don't.
Sep 28, 2003 4:59 PM
|Saturday's road bike club ride stats: 9 riders, 2 aluminum, one carbon fiber, 2 titanium, 4 steel. All bikes purchased within 5 years, most within past 3 years, price range paid for bikes: $1,000-$5,000. Do the math. As Mark Twain said, "Reports of my death are premature!"|
Sep 28, 2003 7:00 PM
|Those stats sound like a politician picking a skewed audience to prove his point! :)
The attendees at your club ride are more than likely "enthusiasts", a slim segment of the population that does not typically share the interests of the general population.
Now try the same head count at any "normal" bike store. You will get 50 aluminum, a few carbon, a few steel, and maybe a titanium.
Sep 28, 2003 8:17 PM
|If I sound like a politician, your comments sound like an aluminum bike rep!
The bike stores I shop carry the better steel bikes (Italian and U.S. made) and Titanium as well as carbon fiber. True, they carry some aluminum, but all with carbon fiber seat stays, forks, etc.and it is a small percentage of the inventory. The more generic shops which carry the mass produced bikes do carry more aluminum. So, it just depends on where you shop. I don't know of many, if any, custom measured and built aluminum bikes, but there may be some.
Sep 30, 2003 8:34 PM
|Then you must be the pitch man for steel!! :)
Soon we are going to all be riding carbon bikes anyway (oh wait, I don't want to start another big debate)...
|Buy a Delorean. (nm)||TFerguson|
Sep 29, 2003 5:14 AM
|re: Why is steel not 'popular'||flybyvine|
Sep 28, 2003 9:33 PM
|When you look at the global market you will see that most of the world's bikes are made out of steel. In the USA you just don't see representatives of 90% of world production coming out of China and Taiwan - just the top end (how many Flying Pidgeon singlespeeds are there in the US ?? - (probably makes a nice collectors item with a funky double top tube - just needs a funky deign name).
It is strange that Steel exists in the market sectors where people know what they want & are informed. In the low end work horse market in Asia, steel is used because its cheap, takes very heavy loads well and can be easily repaired by any guy with a blow torch. At the high end (eg the US) its the material of choice for custom builders where informed buyers understand its properties.
One could argue (although its not that simple) that Alu is the material of choice for the marketing and finance departments.
BTW, the author has interests in bikes spanning from lugged Steel to full Carbon & probably does most miles (commuting) on an aluminium bike that displays the stereotyped Alu harsh ride.
|sidebar on frame material and stiffness||charlieboy|
Sep 29, 2003 5:20 AM
|here's an intersting note on frame stiffness, tube profiles and tube materials... (This from Bebop pedal site, but info still applies to frames)
Engineers have a buzzword for stiffness: modulus. It is a convenient, quantifiable way of comparing the rigidity of different materials. In terms of modulus, the differences between steel, titanium and aluminum are not very interesting. Titanium is half as stiff as steel, and half the density. Aluminum is one-third as stiff, and one third the density. (The buzzword for stiffness as a function of a material's density is "specific modulus." All three materials have essentially the same specific modulus.) So a titanium spindle that is the same size as a steel spindle will weigh half as much, but will bend twice as much. Even if that bending doesn't eventually cause the spindle to break, the constant bending will cause rapid bearing failure (just ask SRP, which recalled all its Ti spindles a few years ago for that reason).
If titanium is so flexible, why does it work so well in other places, like frames?
OK, here is the part you don't hear so much about. You may have read about the modulus of materials before, but even more important is the inherent stiffness of different shapes and structures, sometimes called "section modulus." This is probably the most important (and misunderstood) concept in bicycle frame design. A lot of folks have been talking lately about the "typically stiff aluminum frame ride." This is hooey. Aluminum is only 1/3 as stiff as steel, and anybody over six feet tall who ever tried to ride an early Vitus frame knows it. Folks like Klein and Cannondale make mondo stiff frames by taking advantage of the section modulus of a cylindrical tube. Here's the basic deal: when you double the diameter of a tube, its stiffness increases by roughly eight times. So the stiffness of the basic structure of Cannondale's 2 1/2" down tube is about 8x stiffer than a normal 1 1/8" down tube. Aluminum is only 1/3 as stiff as steel, but because of the vastly increased section modulus, you still end up with an aluminum tube that is more than twice as stiff as the smaller steel tube. So by trading off section against material you can end up with any degree of stiffness you want -- with almost any material. So talk about the "typically stiff big-tube frame ride" and you can impress your friends even if they have plastic pen pockets.
If you've read this far you deserve a medal and should also probably consider getting a life, but I think this answers some of the questions re stiff alu frames;)!
Sep 29, 2003 7:42 AM
Great input on aluminum v. steel. I have time to read this stuff convalescing from a wreck!
|sidebar on frame material and stiffness||dgangi|
Sep 29, 2003 4:00 PM
|That is very interesting information. I heard that most of the rigidity in aluminum frames was designed into the frame on purpose because of tube shape and diameter -- it is not a feature of the metal itself. Just look at any bomb-proof aluminum free-ride mountain bike -- the primary downtube is sometimes >4" in diameter. Now that's how you build a rigid tube from aluminum that can take such large stresses.
What I did not know was that aluminum and titanum were so much less rigid than steel. I always thought it was a much closer ratio.
|Steel is popular at my house.||Leroy|
Sep 29, 2003 7:11 AM
|So is aluminum.|
|Steel is popular at my house.||MShaw|
Sep 29, 2003 10:20 AM
|In my garage right now, I have two steel bikes and three AL bikes. I had a carbon bike up until a few years ago, but sold it to get somethind different (and with a 1.125" HT).
All 5 bikes ride differently. It isn't much, but there are differences.
I'd like to try one of the carbon rear triangle bikes just to see how it rides, but I don't wanna go buy one. Ditto with a new Ti frame. The last one I owned (mid-90s PBS Ti) was a noodle.
|Where in the world are all the steel frames, and who really cares?||Synchronicity|
Sep 29, 2003 9:54 PM
|At first I liked this debate. The first few replies were good. Steel rusts, it's dense, and all K-mart bikes are steel. Simple.
But who smegg'n cares whether most bikes in shops are alloy/ti/cf/steel?
Ride what you wanna ride - buy what you wanna buy. No one can (or should) change your mind about what you prefer.
*If you really like high tech, you'll opt for CF.
*If you value your money, you'll go with Al.
*If you're a retro, you'll like steel.
*If you like metal, and want to spend a bit more, or you don't fall into the other categories, Ti is for you.
Personally, I own: 1 steel MTB, 1 CF bike and soon 1 Al bike.
But there will ALWAYS be a few bikes made from these materials, if there is the demand for them. True, the demand for high-end steel bikes is dropping. Sure, Al is becoming ubiquitous - I even sore it in a BigW store here in Aus!
Simple as that.
WHO CARES WHAT EVERYONE ELSE IS RIDING???
Sep 30, 2003 8:12 PM
|I like how you categorized the frame types. Very nicely done. Of course, the steel riders on this board won't like being called "retro". That phrase comes with all sorts of baggage...
|That's funny.....||Mike Prince|
Oct 1, 2003 6:01 AM
|To many being called retro is a compliment when it comes to bicycles.
Personally, I ride a steel bike with a steel fork and a steel stem all made by a guy named Steelman. Now that's funny...
Oct 1, 2003 10:19 PM
|More power to you! The only baggage that comes with aluminum is the cost of the kidney transplants!!!!!!|
|now THAT'S a good question||Mink|
Oct 4, 2003 6:05 AM
|WHO CARES WHAT EVERYONE ELSE IS RIDING????
I think the short answer is - we all do. Would anyone have read or replied to this forum if they didn't? Would anyone buy Trek if Lance wasn't riding it?
|aero tubing in steel: yes||powergyoza|
Oct 1, 2003 6:03 PM