Hacker News Reader

Comment by ctrw | Hacker News Reader

Yes imagine how well a cast iron bike would handle. Or a wooden one. There is a reason why even steel is not used any more in bike frames.

View on HN

Steel is literally the most common used material in bike frames.

In the US aluminum is more common than steel for new frames now.

Same in Europe. Steel has increasingly been phased out starting sometime around 2010, so almost 15 yrs ago now. Even budget bikes (~200-300€ new) are generally aluminum now.

Not in Holland, everyday bikes are still steel because they're just that much stronger. Especially women's bikes because they support the frame only from the bottom.

Cheap bikes in Canada are still steel-framed.

Source on that? Most bikes I've seen are made with aluminum these days.

That mostly says something about the socio-economic status of the people commenting in here, going to any big Walmart-like store in the Western world most of the bikes for sale there are still made of steel, not of aluminium or other light materials. I'm talking about basic bicycles like this one [1] (I had one from the same bike manufactured), they're made out of steel.

[1] https://www.emag.ro/bicicleta-oras-dhs-citadinne-2812-28-inc...

How certain are you that bike is made of steel? That sort of flat and fat tubing is typical of aluminium, since it is a weaker material than steel in terms of cross-sectional area.

They have been shaping cheap steel bikes like that for years to make them look like aluminum. Some of the buyers aren't even looking for an aluminum bike, they just want a 'bicycle' that looks modern. It's a pity because it means the bike is much heavier than it would be if it had nice slim steel tubes.

Oh, wow. I did not expect that but it makes sense. Thanks!

The datasheet says it is made of steel.

Material cadru Otel Material furca Otel Material spite Inox

Any discount store bicycles in Australia are made in China and all have aluminium alloy frames from what I have seen. (Most are of a mountain bike or BMX style)

I went to Big W website and the first bike I clicked on with the default sorting order has a steel frame.

https://www.bigw.com.au/product/repco-blade-26-mens-mountain...

If you walk into a high end bike shop you won't see many steel bikes, you'll see them mostly with higher end materials like aluminum, titanium, or carbon fiber.

Most people aren't getting their bikes from a high end bike shop though, most are getting their bikes from discount shops like Walmart, which sells mostly steel bikes.

First result on Google is steel:

https://www.walmart.com/ip/Kent-Bicycles-27-5-in-Male-Sea-Ch...

here is an up to date list of steel framed bikes with eye watering pricetags

https://www.theproscloset.com/blogs/news/steel-is-real-12-st...

Steel is a great material for bike frames. Cheap, strong, fairly light when in tubular form.

Now if you’re trying to save every last ounce and someone else is paying for the bike, sure go carbon, but the vast majority of people are not even at the fitness level to really “need” a carbon bike.

Agree! My current racing bike uses chromoly steel, which is somewhat stiffer and stronger than regular steel, so they can make the tubes thinner. I can attest it’s very light as a result. Maybe not as light as a modern Aluminum frame, but still, very very light, and I guess more durable.

>not even at the fitness level to really “need” a carbon bike

just want to point out that a high fitness level allows you to get more out of heavy bicycles. Any couch potato prefers carbon.

It's my understanding that steel is one of the more repairable metals? Aluminium and carbon fibre can't be welded as easily (in the case of aluminium) or at all (in the case of carbon fibre).

Steel framed bicycles are good enough for the vast majority. I fear bike manufacturers are switching to less repairable materials and proprietary parts to increase profits.

Steel has a better failure story than carbon fiber. Many impacts that would shatter a carbon fiber frame, dangerous to the rider, will only bend a steel one. Carbon fiber makes sense for a racing bike, but for street riding I'll stick with steel.

A friend of mine was nearly killed on a carbon fibre frame that just tore itself apart while going up a hill and threw him into the road, unconscious. I would never touch one for street riding.

Was the frame damaged before? I have ridden 4k miles on my carbon road bike and I've never felt like it was going to fall apart.

I ride road/street almost exclusively, and the Bay Area roads don't do my bike any favors

Carbon fiber frames can be challenging to see the cracks and damages to it before it spectacularly fails. There's a good chance you won't know it is about to break until it shatters.

Any material under stress gets fatigued. The problem with carbon fiber specifically is that there are practically no visible signs of it reaching the threshold.

Some materials (steel and titanium being the most common) have infinite fatigue limits. They can be designed to not get fatigued.

Nope. As far as he knew it was in complete working order with no suggestion it was about to fail catastrophically until he woke up on the floor.

This is incredibly uncommon.

While horrifying for your friend, it's very low on the list of the risks that come with bikes.

It might be less uncommon than you think. https://www.outsideonline.com/outdoor-gear/bikes-and-biking/...

I don’t know how common it is, but why would you take that risk on the road for a couple kg of weight savings? If you’re racing competitively that’s one thing, but is it worth it on the commute?

> I fear bike manufacturers are switching to less repairable

Is the frame really an issue though? I don't aluminum frames break that often, I'd bet that's probably one of the least common problem for modern bikes (gears, brakes, suspension etc. are way more fragile). Most bikes are likely to be discarded way before the frame would need to be repaired. It seems totally like a red herring to me..

> Steel framed bicycles are good enough for the vast majority

Well most people don't seem to agree. There are still plenty of steel bikes available, even relatively high-end ones, they are just not that popular.

Yes, steel, especially non heat treated 4130 crhomoly is repairable at just about any metal working shop. That's why it's the choice of bicycle tourers and custom frame builders. Also a steel frame is very dependable, bicycle enthusiasts usually rebuild thier steel frame a couple of times during its lifetime. Last year I bought a lugged steel road bike frame that has the same age as myself and build up with a mix of vintage and contemporary components with vintage looks.

Alloy, titanium and carbon fiber are lighter and that's what most consumers want, having watched Tour de France and bicycle industry marketing materials. Big brands facing increased competition from Asia started to put carbon frames of questionable quality on the market, so if you want an okay bike you are best served by alloy, because they're mass produced and the process is quite optimized and well understood. Titanium is basically unrepairable without special tooling and know how and it feels basically the same as alloy. It's stronger and more corrosion resistant.

The bike industry also puts a lot of new or proprietary standards on the market, especially when it comes to bottom backets. Other new standards include different fork spacing, head tube diameters, rear suspension couplers, proprietary frame integrated suspension and more recently integrated e-bike batteries. The worst offensers are Cannondale, Specialized, Trek and Cervelo.

If you want a bike with sensible standards you want a BSA threaded bottom bracket if it's a metal frame or BB86/92 press fit if it's a carbon frame, a fork with a 1 1/8" steerer or tappered from 1 1/8" to 1 1/2" steerer if it's a mountain bike or a high end road bike, a 34 mm or a 44 mm head tube, 135 mm O.L.D. rear and 100 mm front fork spacing for quick release skewers or 148 mm/110 mm boost spacing if it's a newer mountain bike or 142 mm/100 mm spacing if it's a newer road bike with thru axles, a seat post diameter of 27.2 if it's a road bike or 31.6 mm if it's a newer mountian bike. For brake mounts I prefer IS brake mounts because they're robust, don't have threads to cross thread and misalignment issues are not common, but modern road bikes come with the flat mount (FM) standard and newer alloy MTBs come with post mount (PM). What you probably don't want is a mountain bike with flat mount brakes, funny axle standards, direct derailleur mounts, integrated seat posts, integrated cockpits, full internal routing, lefty forks, integrated frame suspension and so on.

Carbon fibre frames can actually be repaired and there are quite a few companies that do it. In fact I'd go as far as saying that the damage that would write off an aluminium frame can be repaired with a carbon one in 9/10 cases. The problem is that you really need specialist equipment and know-how to do it, which drives the prices up, a steel frame can be welded by almost anyone with some basic knowledge and tools.

>> I fear bike manufacturers are switching to less repairable materials and proprietary parts to increase profits.

So I kinda disagree, there is greater interoperability in bikes now than there ever was(imho). Many SRAM parts can be used with Shimano parts and vice versa, nearly everything is still easily disassemblable and repairable by someone with a work stand and a set of tools.

The biggest "threat" to bike repairability is unfortunately electrification - motors and batteries are essentially black boxes that while repairable(nearly all ebike motors are right now) the skill level to do so is significantly higher. And batteries are of course disposable, no one repairs them as far as I know. Which is a shame because buying an ebike has been completely transformative for me with MTB as a hobby - it removed some mental barriers for going out on my bike out of fear I'll get too tired to continue, with an ebike I go much more often and ride for longer and further. But while I can do 90% of the maintenance on it myself(and I think anyone can with a bit of spare time), if the motor goes I'll have to rely on a third party to fix it.

Steel bikes are more typically extremely cheap bikes nowadays. Too cheap to bother repairing in any way that the material choice would matter.

Carbon can be easily glued and recooked to be as new.

Steel is very common, and there are many bicycles made mostly of wood (while not particularly common today).

Bamboo too !

There’s a bamboo bike building workshop in San Francisco. You see people on these bikes now and then.

Steel is less common, but not really for performance reasons. There are plenty of lovely steel bikes, and they are more durable and just as light. Feel is also nicer (although this slightly more subjective). Ali is just cheaper to manufacture.

There are plenty of lovely steel bikes but steel is definitely less common for performance reasons.

It's neither more durable or lighter than frames made of aluminium, titanium or carbon fibre.

For example, a typical frame made of steel will generally be about 1kg heavier than one made of carbon. The forks will 500g heavier. If you scratch or chip the paint steel will corrode.

The claims that steel (or titanium) "feels" better than aluminium or carbon fibre have been thoroughly debunked.

The Young's Modulus of steel tubes used in bike frames ends up almost exactly the same as aluminium or titanium and steel has no "magic" vibration absorbing qualities.

Carbon fibre is the only frame material with any real vibration damping and even that is massively over-hyped compared to an actual shock absorber or even bigger tyres.

If you want to choose a steel frame then it should be because you like the look, it's easy to weld, uses less energy to make or it's cheaper.

> "The claims that steel (or titanium) "feels" better than aluminium or carbon fibre have been thoroughly debunked."

Have they? Do you have support for that statement?

Why is it so implausible that different materials might feel different? I did a (non-blind) comparison of steel versus carbon fiber, and they felt very different to me. They also certainly sound wildly different if you just tap your finger on steel frame versus a carbon fiber frame, so a different "feel" that corresponds to higher frequency vibrations seems plausible.

Yeah there’s loads of research into it for both bikes and wheelchairs.

Here’s a video from Cycling About that gives a good overview:

https://m.youtube.com/watch?v=Lb4ktAbmr_4

I do not see any relation between effectively static strain gauge versus force measurements and the "feel" of riding a bike in terms of high frequency vibrations. The rest of the video is just the confidently stated opinions of a random person.

OK what do you think contributes to good "feel" of a bike frame, with regard to high frequency vibration, then?

I mean what frequency would you class as road buzz? With that we could start to analyse what's going on.

When I look at the damping ratio of steel[1] I see something around 0.01 - 0.05 which is under-damped.

Carbon fibre can be somewhat better at between around 0.1-0.3 i.e. an order of magnitude better but still not what I'd consider a shock absorber.

I'd be surprised if much high frequency vibration that's made it through the tyres is actually damped by the frame.

With regard to non-blind, anecdotal comparisons I own and regularly ride bikes made from steel, aluminium and carbon fibre. I'm in the camp that thinks a long flexible seat post will do much more for comfort than frame material.

If you know of a study showing otherwise though, I'd be really interested to see it.

1. Sorry I can't find exact figures for 4140 CroMo but I don't think it's outside of this range.

It was a long time ago that I compared bikes, but I remember really feeling the texture of all the little pebbles that makes up road pavement on a carbon fiber bike. Then with an old steel bike, it felt as if the road had been polished into smooth glass surface. This difference was especially noticeable in the feet.

At the time, I assumed the difference was the frame material, but I really do not know the cause. I do believe there is something that could be quantified as opposed to just a psychological effect, but it could be something non-obvious like the typical curved shape of old steel forks; or the frame geometry or tube diameters; or even something else that just correlates with frame material like the tendency of old steel frames to have hand-built wheels with lots of spokes as opposed to the newer (seemingly) rigid factory wheels with fewer spokes.

Your anecdote is exactly the same as all others claiming to be able to tell the difference - there's not enough information in it for anyone to be able to make a judgement either way.

I would expect that a person conscientious enough to know how shocks, wheel size, tyre type and pressure, saddle type, and speed affect ride comfort would also include that information in their post.

Therefore, these anecdotes amount to "I rode on two different bikes which happened to have different frame materials and I could tell a difference in the amount of vibration." Meaningless, even if we don't consider human biases, after all these aren't blind tests.

I would be curious to know if there is a difference that can be felt, but in the end it's of no practical use. I bet even slightly adjusting your tyre pressure will have 10x the impact of any possible difference in frame material.

My basic argument is just that it is plausible that the perceived different feel of different frame materials is real, and that there is no support for the claim of another comment that a different feel is impossible. I am surprised that no one seems to have done any convincing experiments.

I could have left out my anecdote because it is subjective and prone to bias and error, but it is how I believe I can rule out (some of) the commonly cited reasons of different bike feel -- seat posts, because that would not affect vibrations coming through the feet; and tire pressure, because different tire types and pressure have their own different and recognizable feel (e.g. responsive and jittery with high pressure, squishy and sluggish but not silky smooth with low pressure).

> I did a (non-blind) comparison of steel versus carbon fiber, and they felt very different to me.

Meaning, you switched out the frame on a bike from steel to carbon, keeping everything else, and felt a difference?

I did not mean to imply that I had, but with the billions spent by the fitness cycling industry pushing out "cheap" aluminium and carbon fiber frames against the popular "myth" that steel feels smoother, you would expect that someone would make the effort to do a reliable test, assuming it really is a myth.

>If you scratch or chip the paint steel will corrode

this isn't really true.

yes, exposed steel will show rust, but that's not what "corrodes" iron to the point of weakness. to corrode in a way that weakens iron, it needs to be kept wet over an extended period of time. If you've seen an old car with holes rusted through, that has occurred "from the inside" in places where water can collect and sit. The outside of objects will dry after rain, and such corrosion will never be a problem beyond aesthetics.

>steel has no "magic" vibration absorbing qualities.

Steel does have an infinite fatigue life while aluminum does not. From that standpoint, it is a more durable material.

All my bikes are steel because I've cracked & snapped numerous frames over the years from riding them too hard. During my racing years (2005-2015) at least one rider would crack their frame at each race weekend!

My grandma had a wooden bike that she rode to school, that was back in the 1950s Poland.

Reply on news.ycombinator.com