You say that aluminum is at the bottom of the heap when it comes to bicycle quiality and longevity. But the industry says otherwise. Look at mountain bikes, the frames undergo more stress than any other kind of riding and the vast majority of them are aluminum. There are very few steel mountain bikes in the catalogs of major producers. That's a trend that has been around since the mid90s. And, if steel is the 'premium source' as a bicycle material, why don't more large producers make more of them especially for applications like mountain biking? Up until just a few years ago (less than than 5?) bicycle catalogs were filled with aluminum bikes even at the highest price points.

Any bike been around since 1936, has a legitimate claim to longevity. Sure there are more, and older, steel frames out there but they were made in far greater numbers than were aluminum bikes of the '30s.

Finally, I'll ask the question I always ask in the 'steel vs aluminum' debate: If you are so concerned about longevity and strength, why aren't you riding on steel wheels with steel stems and steel seatposts and steel handlebars and steel crank sets? You are the one who said that "aluminum is an inferior metal when it comes to fatigue life, stress thresholds, and flexibilty as compared to steel"

This is a really good point. It also puts the issue of denting in perspective. I've got an aluminum cyclocross bike that I've crashed more times in races than I'd care to admit and it doesn't have a dent on it.

Aluminum is cheap and more easily accessible as a material resource due to it high potential for recyclability. It's much cheaper to recycle aluminum than steel. It's also cheaper and faster to produce bicycles from aluminum, than steel.



That's only because, it's a cheaper material that is easier to reproduce, as previously stated. Steel is heavier and costs more to transport. It also costs more to recycle steel than it does, aluminum. Producing bicycle frames from aluminum is faster than producing frames from steel. Also, since its easier to damage aluminum than steel, when aluminum is damage, the cyclist is forced to return to the bicycle market to replenish himself with yet, another bicycle $$$.

As already stated, the reasons for the industry preferring aluminum over steel, is more related to industry economics$$$, than cyclist's riding comfort and performance satisfaction.

I have personally witnessed larger numbers of failed aluminum frames, than steel frames. Aluminum has a very small yield capacity, causing it to break rather than bend. This weakness is the primary culprit in the demise of the failed aluminum bicycle.

I personally, don't see too may older aluminum bicycles...Where are they all?

Since aluminum is a cheap material to work with, it is the preferred workhorse material of the bicycle industry. It also does not succumb to oxidation as easily as steel. Due to these most salient properties in addition to the fact that aluminum is light in mass, bicycle manufacturers find it most profitable to supplant the superior metal, steel with this most excellent economical substitute.

Also, whereas the wheels are concerned, the aluminum rim legitimately deserves a higher status than steel, due to its higher coefficient of friction when coupled with composite braking materials.

However, overall aluminum is a fair substitute for steel, when time is not a factor. It will provide a cyclist with an acceptable degree of service for a limited time period.

In time, it really doesn't serve the cyclist well, since it's such a transient recycling product.

- Slim

So here's the pivotal question: what is the service life of an aluminum bike frame?

I'll grant that a steel frame will last longer. Properly cared for and not damaged in a crash, I wouldn't be surprised to see a well made steel bike last 100 years. Of course, that isn't much of a benefit to me personally since I won't last that long.

Will my aluminum bike last 20 years? I'm hopeful I'll still be cycling then, although I may have to go to the retro-grouch LBS to find a 1-1/8" headset and an English threaded bottom bracket.

Honestly, I'm not sure this question is answerable, because I think the life of a well-built aluminum frame is longer than the time since the bicycle industry started producing well-built aluminum frames.

Again, too simplistic. If you start with raw ores, steel is far cheaper to make than aluminum. Both are as easily recyclable and recycling costs about the same. Aluminum just happens to be cheaper to make from recycled materials than from raw ore. A mountain bike Columbus frame set in 7005 aluminum cost $125. A similar frame set in Columbus steel cost roughly the same. If you are making bicycles in a factory, the production costs are about the same but the aluminum has to undergo annealment after welding. For a small shop manufacturer, the annealment process is expensive enough that most just use steel because it's easier to deal with.


Steel is heavier but the extra costs of transportation is minimal. From a rider perspective, steel is much heavier. A steel frame with all the manipulation required by dual suspension would weigh 15 lbs instead of the 5 lbs an aluminum frame weighs. Mountain bikes are already heavy, adding another 10 lb wouldn't make them better.

As for the cost of production, the $100 bikes at HelMart are generally steel because they can be produced in large quantities for very little money. Kids bikes are steel because they can be produced cheap and quick. Aluminum bikes, when they first hit the bicycling market in mass (around 1985), were the most expensive bikes to purchase. Klein and Cannondales weren't cheap. All the other companies selling steel bikes sold much less expensive models.

Nope. It's related to the market. Most cyclists don't want a bike that weighs 3 times more. They want a light weight bike. That's why carbon is beating the pants off aluminum which beat the pants off steel before it. Steel has a higher density than aluminum which has a higher density than carbon. Simple chemistry. Yes, you have to use more aluminum to make a bike that is as strong as the steel one (as well as using more carbon to accomplish the same thing) but the amount of extra aluminum isn't 3 times as much so the aluminum bike is lighter.

I've had 4 frames fail on me. Two steel and two aluminum. The aluminum didn't 'break', it cracked and tore as I'd expect aluminum to do. It isn't brittle. The steel frames did 'break' as in fracture. They didn't bend, they didn't warn of impending failure, they just broke. I'd expect that out of steel because steel is a brittle material. I've broken aluminum parts and steel parts, the same mechanism held in each case. Aluminum tears and is more of a slow failure. Steel (axles mostly) goes 'snap' and is in two pieces.

I see lots and lots of them. At the co-op I work at the number of failed aluminum frames is about equivalent to the number of failed steel frames. We don't see a lot of very old (pre 1990) aluminum bikes because the majority of bikes made before 1990 were steel. From 1990 to around 2000, the ratio is closer to 1:1 and the number of aluminum bikes we see reflects that. It also reflects advances in the technology to produce aluminum frames and the market demand for a lighter bike.

Yep, since 1997 or so, steel hardtails are either non-existent or only bottom rung in major companies' MTB lineups. I'm glad this trend is showing signs of reversing.

In a perfect world any decent major bike company would offer equal choices of XC hardtails in Steel, Carbon and Aluminum.

Don't have an informed opinion on this subject--for no particular reason, I've only owned steel bikes--but I just bought a 1993 Bianchi Ibex hardtail mountain bike with a lugged steel frame to use as my winter commuter. I like it very much.

I've seen that too, on a LeMond.

Regarding whether to pick steel or aluminum for my commuter, I was using an aluminum Gary Fisher Ziggurat for a while as my main commuter, then got a Surly Troll (butted chromoly). Now I've switched back to the Zig; the Troll is so heavy it's actually tough to get up/down a flight of stairs, which is something I do four times a day when commuting. Anyone who thinks it's worth that much extra weight will have a chance to bid on a 22" Troll at Ebay very, very soon

Not to mention flying on steel aircraft I see the aluminum Boeing B-52 strategic bombers will be in service for about 90 years before ultimate retirement. I do still have one steel bike (Soma Smoothie ES) but wouldn't hesitate to knock a few pounds off that one with an aluminum frame upgrade either.



What I find amusing is that someone is criticizing aluminum for durability, while his signature has links praising bikes with some of the worst track records anywhere for breakage. If I had a dollar for every broken Madone I've dealt with, I could have pizza for a week

Don't know, but my aluminum Cannondale is 22 years old and has 112,000 miles on it without any problems other than the usual wear items (tires, chains, cassettes, cables, brake pads, one chainring, front rim - worn out brake track). I've had two steel bikes break that had much less mileage - so far the Cannondale is my only aluminum bike.

Cyccommute says:

This statement is so inaccurate, it's almost hilarious. The bayer process, is a much more expensive process. Extracting aluminum from bauxite is a more expensive process than the extraction of iron from its ore to make steel. This expense is further exacerbated by the Hall-Heroult aluminum refinement process, where aluminum ions are reduced at the cathode (pots) to become the aluminum metal. Alternatively, recycling aluminum is cheaper and less complexed than recycling steel. Since iron (Fe) has a melting point of 1535 C and aluminum has a meting point of 660 C. It becomes painfully obvious to us all as to the actual reason that industrialists would prefer to use aluminum as a bicycle frame and not steel. It takes a lot more energy to get to 1535 C than 660 C . Therefore, simply put. It's cheaper!

Poppycock!

Steel is much heavier than Aluminum. Raw materials and their products ship by weight. Therefore, it costs more to ship steel than aluminum. Industrial profiteers understand this fact, and make modifications, accordingly. Even if the savings were just a a few pennies on the dollar, the bicycle industry would stand to save billions over the years, simply by making the transition from steel to aluminum. That's the real reason that we're all riding aluminum bikes. It's because of industrial profiteering, it's not due to bicyclists' taste in frames changing. It most certainly is not due to the bicycle industry wanting to provide cyclists with a better and more efficient bicycles.

I remember when most bicyclists initially suspected that aluminum frames had their misgivings and they had grave doubts about the future of aluminum bicycle frames. As it turns out, they're suspicions were valid, but the bicycle industry thwarted their predictions, with cosmetic engineering and technology.

In most instances, there's only two to four pounds difference between a racing road bike made of carbon and a racing road bike made of aluminum or steel. I don't know where you got your information. No modern-day bike has ever weighed three times more than another!
If the industry made more chromoly steel bicycles available, instead of saturating the market with aluminum bikes, you would see many more chromoly steel bikes on the road today.


I don't know what planet your steel comes from, but steel almost always tears or bends, before it breaks. That's not something we can say about aluminum. Aluminum has a very low yield capacity, making it more susceptible to breaking or snapping. To that extent, you have the properties of the two metals, reversed.

Thus far I've owned about about a dozen bicycles in my entire life. I've never had one to fail on me. All of my bikes have been made of steel. I currently own a Trek 7.5FX. It's frame is aluminum and it's doing quite fine.


Well that hasn't ever been my experience. I've always seen many more failed aluminum frames than steel frames. I've also always heard more rumors about associates aluminum frames failing. Haven't heard much about steel frames failing. The only type of frame failure steel bikes seem to have is derived from the result of accidents.

- Slim

I only own steel boats. They aren't like aluminum, but if you keep them dry they won't rust and they will last forever. You should all buy a Jamis Boata Sport.

You must be bored. That's the corniest you've ever posted!

The Surly Troll isn't heavy because it's steel. It's heavy because it's heavy. LHT's are pretty heavy for touring bikes too.

This bike is 24.5 pounds as pictured. Just over 23 pounds without barends and with slick tires installed. And it's just a mid-range hardtail.




This Aluminum hardtail was just over 28 lbs:



This steel touring bike is over 26 lbs with its original front wheel and without lights and Big Gulp.

Do we want to travel down this path again ?

Aluminium has proven itself as a sound material for bicycles and accounts for most of the bicycle sales on the planet.

On the other hand... steel is real.

Maybe one of the best bicycles I have ever owned was Aluminium... on road, off road, summer, winter, touring, towing... you name it... it could do it.









My friend now has the Trek because she wanted a really great bike and I have spares.

The Bayer process isn't the expensive, energy intensive part of aluminum production - the subsequent Hall-Heroult process, by which the alumina obtained from the Bayer process is electrolyzed in molten cryolite at over 1000 degrees Celsius is the expensive part.

As far as recycling goes, I see nothing inherent to steel that would make it more complex to recycle than aluminum. It's the same basic process - clean, melt down, re-cast - whether you're talking steel or aluminum. And if nothing else, the magnetic nature of steel would make it easier to separate from other materials, which would aid in the recycling process.

The Chemist says:


While it is true that the Hall-Heroult process substantially adds to the expense of the production and refinement of the aluminum metal, the Bayer process remains an expensive component of the separation process. It is most certainly more cost intensive than the extraction of iron from its oxides. Therefore, the original statement remains true, factual, and intact. However, you're absolutely correct in your assertion that the Hall-Heroult process drastically attenuates the overall cost of aluminum refinement.


Since the melting point of Iron (Fe) is 1535 C and the melting point of aluminum is 660 C. It becomes quite obvious as to the reason that aluminum is the much preferred recycling material. It takes much more energy to reach 1535 C, than 660 C. Refining aluminum therefore, becomes a much less energy intensive process. Subsequently, reduction of required energy, translates into less cost!

- Slim

You may want to go back and reread what I posted. I said exactly the same thing you just did.

Yep. Costs more to ship raw steel than raw aluminum. But, as finished products, the weight differential isn't enough to have much of an impact on shipping costs for bicycles.

But if you have to power the machine with a weak power plant, i.e. a human with ~1/4 of a horse power, the weight of the machine becomes very important. Why do you think we are so obsessed with weight?

Two to four pounds is huge! And I get my information from the densities of the materials. Steel weighs 3 times as much as an equivalent volume of aluminum. The volume of material to make a bike of the same size and geometry are almost equivalent. You can shave some volume from steel, or conversely, add some volume for aluminum to account for the strength of the materials. But if you melt the bike down and measure the volume, you'll only differ by a few percent.



Seriously? "Steel almost always tears or bends before it breaks"? Ever broken a pedal spindle? They don't bend. They just break. Ever broken a spoke? Again, they go 'ping' and are broken. I've broken frames and the steel ones never tore nor bent before they broke. They snapped. The aluminum ones cracked and creaked and tore apart but they didn't 'snap'. Even an aluminum that was made to be very stiff (Specialized M2) didn't just snap. Cracks propagated from stress risers but they 'snap'.

Now how is it that you have "personally witnessed larger numbers of failed aluminum frames than steel frames" and you've never broken a frame?

You need to get out more. Steel frames can fail through more modes than "derived from...accidents". From my personal...and I mean 'it happened to me'...experience, I've had steel failures at the dropout, at the steer tube on the fork and at the bottom bracket bridge, twice. Even after repair, the bottom bracket bridge broke again outside the weld area. I've also had axle failures, pedal spindle failures, spoke failures, bolt failures, etc. all of which, including the frame failures, were rapid failures.

I've also experienced aluminum part failures such as rims and cranks. I've had rims crack down the middle of the rim and I've had the sidewalls break as well as cracks around the spokes and mild spoke pullouts. The cracks down the middle of the rim are perfect examples of the failure mode of aluminum. The tire pressure...these were all narrow mountain bike rims running wide mountain bike tires...bows the rim outward and pulls the middle of the rim apart. The aluminum 'tears' from spoke hole to spoke hole exactly like these rims. Picture borrowed from here



If you look closely at the picture, you can see crack propagating from one spoke hole to the next. But you can also see cracks propagating past spoke holes. If the failure mode was sudden, the large spoke hole should have stopped the crack but it didn't. The cracks are the result of the aluminum tearing due to the outward force placed on it by the tire's air pressure.

You don't get any style points for aluminum. Some for steel and carbon, and the most for titanium.

My mid-range aluminum XC hardtail is slightly under 19 pounds with a rigid fork and tires that small, which is the config I use for the Midnight Century. Oh, and it's an XL 21.5" frame In proper XC trim (big light tires and a suspension fork), it's 21-22.5 pounds depending on which wheelset I use. And that's not that special these days, just competitive.

I just bought a 2001 LeMond Nevada City -- steel frame and fork. It looks like with the newer components I'm using to rebuild it it is going to come in around 19 pounds. Of course, by road bike standards these days that's a boat anchor.

If you want to lighten it up a bit, a Ritchey Comp carbon fork in 1" threadless would help. That's what I did with my Paramount, which I later sold off the frame/forks and stuck the parts on an aluminum Trek (the Precious was too fancy, I couldn't stand to actually let it get dirty). The Comp model has an aluminum steertube and dropouts, so it's not as light as an all-carbon fork, but pretty worry-free. They're about $200 and 440 grams.

While I have to admit that I am a bit of a weight weenie, I only paid $300 for the bike and it's lighter than anything else in my garage except maybe my scandium Major Jake. Still, with that fork and some Ksyrium Elite wheels I might be able to get it below 18 pounds.... Hmmm....

The threadless stem will help too.

Yeow! That's light. We might have different definitions of the term midrange. For the 1996 'goose it's MSRP $760, weight of bike in completely stock trim.

The goose is a couple pounds lighter than the other poster's Aluminum Gary Fisher and since he was complaining of the weight of his Troll build probably lighter than that as well. It stacks up nicely against the 25.9 lb GF Marlin of the day, which cost over a grand but had a Quadra fork. Replace Quadra with a $100 rigid fork and you won't shave much weight cuz Quadras were pretty light already.

Probably have to break out the big guns to compete against this bike you're talking about in the weight arena. I reckon a Ritchey P-20 could stack up.

I'm trying to think who had really light midrange Al. Cannondale's rigid M900 was 23 lbs/$1250, so more highend than mid range. Klein Adroits were nice and light, but big sticker @ $2200.

Probably true, because today's mid-range bikes include tech that was non-existent in '96. For a hardtail, high-end today is carbon bikes starting in the $5000ish range, e.g. a Trek Elite 9.9SSL or Specialized S-Works, low 19 pounds out of the box without pedals.

My mid-range XC bike is currently an aluminum Trek 8500 frame I bought off Ebay for $168, with my old XC parts kit from my (cracked) carbon Trek Elite 9.9. Basically the parts kit off this bike, installed on an aluminum frame: