A Cyclists Guide To Bike Frame Materials: Carbon Fibre

Carbon fibre-framed Team Sky time trial bike
Carbon fibre-framed Team Sky time trial bike

Welcome to the second in my series of posts on the materials used to make bicycle frames.

**UPDATE: The full list of ‘materials’ posts can be found on my new page dedicated to bike building: How To Build A Bike **

Readers of my previous article (which you can read here) will no doubt have been shocked, intrigued and ultimately delighted by my razor-sharp insights into the world of steel manufacture.

Now it is the turn of the young pretender to the throne: carbon fibre.

Virtually the entire professional road cycling world, and certainly all of the teams at the ProTeam level, use carbon fibre frames for their road race and time trial bikes. This would tend to suggest that, as a material, it has certain performance benefits.

So now, why don’t you join me, as we go … through … the … keyhole investigate the hi-tech carbon fibre industry.

What is carbon fibre?

Or carbon fiber, if your spelling is of a more American persuasion.

Carbon fibre is the shorthand term for carbon-fibre-reinforced polymer. Fibres are used to reinforce a polymer (normally expoxy) in order to create a light but very strong material suitable for making things that need to be, er, light and very strong.

The layout of the carbon fibres, and the proportion of carbon to polymer, allow manfacturers to vary the strength and rigidity of a piece of carbon fibre to suit its particular purpose.

How are carbon fibre frames constructed?

The individual pieces of carbon fibre are molded into their desired shapes. Once a mould has been created, sheets of carbon fibre cloth are layered within it and the epoxy is introduced. The contents of the mould are heated in order to bond the elements together.

As to how the bike frame itself is then constructed, the short answer is, ‘it depends’.

You can get carbon fibre tubes and lugs which are then joined together in much the same way as you would with steel tubing (albeit using glue rather than welding equipment).

Alternatively, you can form an entire section of the bike (for instance, the front triangle) using a single piece of carbon fibre before joining it to the other pieces of the frame.

A carbon buzz word that you often hear thrown around is ‘monocoque’. It sounds cool (very ‘racing car’) but is a bit of a misnomer in the cycling sense. Strictly speaking, monocoque refers to an object that derives its structural strength from its skin, rather than the underlying frame. Since a bike is only a frame, the word is a little nonsensical.

That said, the term is used to describe bikes that are made from a single piece of carbon fibre with no joins, such as the Lotus bike used by Chris Boardman to win gold at the 1992 Barcelona Olympics.

Presumably, to the Spanish, monocoque can also refer to the appendage of a male monkey.

Who makes carbon fibre for bikes?

The main suppliers of carbon fibre used to make bike frames and components are Japanese, and enjoy exciting names such as Toho Tenax, Toray Industrial and Mitsubishi Rayon.

The companies responsible for turning ‘raw’ carbon fibre into individual frames and components are almost entirely based in China and Taiwan. The manufacturers work with bike makers and designers around the world to implement their carbon visions.

Why do people choose carbon fibre for bicycle frames?

The two main arguments in favour of carbon fibre frames, at least from a professional racing perspective, are weight and aerodynamics.

All else being equal (and let’s face it, they rarely are equal), a carbon fibre frame will be lighter than an equivalent quality and strength steel (or titanium) frame.

The process of manufacture allows bike makers to produce frames sculpted to maximise aerodynamics. Using computer simulations and wind tunnel testing, frame (and other component) designers can adjust the shape of the bike to reduce air resistance and ultimately allow it to go faster.

The lightweight nature of carbon fibre means that such aerodynamic augmentations can have minimal impact in terms of increasing bike weight.

What are the limitations of carbon fibre as a frame material?

It is important how we define strength (i.e. in my description of the advantages of carbon fibre above). There are a number of properties that might come under the umbrella term, ‘strength’, in which carbon fibre underperforms other materials.

Carbon fibre is a less durable material than, for instance, steel. It is more likely to crack or shatter when something strikes it (or, more likely, when it, and you, strikes something else).

An important factor, particularly if you’re riding the bike at the time, is the speed at which the material fails. If steel receives a dent or a crack, it will generally continue to perform its function for a time. Carbon fibre, on the other hand, tends to fail ‘catastrophically’, which sounds… er, entertaining…

Fin

As I’ve already mentioned, this post is one of a series looking at all materials that are used to make bicycle frames (well, all sensible ones at least). If you’ve missed it, be sure to take a look at my barely-disguised love letter to steel (here’s the link again).

In future posts I’ll be looking at aluminium, titanium and wood, plus any other materials I discover in the meantime.

I do hope you’re finding the series interesting. Please do share it with your own personal peletons (or just click one of the buttons below).

I look forward to welcoming you back to the Grimpeur Heureux soon. Until then, I hope your road surface remains smooth and the wind is always at your back.

Chapeau!

Andrew

A Cyclist’s Guide To Bike Frame Materials: Steel

Steel framed bike
Simple steel beauty

Most people with any interest in bikes will have at least a passing familiarity with the materials that are used to make them.

The sculpted, wind tunnel-honed lines of pro peleton bikes are unmistakably formed from carbon fibre. The skinny  road bikes of old evoke images of bespectacled engineers in oil-stained overalls, squinting at steel tubes in complex jigs.

But do you know how these materials are used to make bikes that meet the needs of cyclists in the 21st century?

The basic diamond shape of a bicycle frame may not have changed significantly for more than 100 years, but the materials used in their manufacture have progressed considerably.

In this series of posts, I am going to look in detail at what bikes are made from: why those materials were chosen, who makes them, and how they are used to make a bike.

**UPDATE: The full list of ‘materials’ posts can be found on my new page dedicated to bike building: How To Build A Bike **

My first choice of material is steel, a metal whose own development over the past century has been interwoven with that of the bicycle.

So, whether you’re a man of steel or an Iron Lady (or any other superhero/1980s British prime minister), I hope you find something useful in this post.

What is steel?

The question you’ve always wanted to ask!

[quote style=”boxed” float=”right”]Men are like steel. When they lose their temper, they lose their worth – Chuck Norris[/quote]

Steel is an alloy of iron and carbon, amongst other elements. The types of steel used in bike manufacturer vary from lower quality metal (carbon or high-tensile steel), similar to that used in car production, through to specialised steel alloys.

Higher quality steel bikes are generally made from alloys. You might remember the name of one of the more familiar steel alloys, chromium-molybdenum or ‘chromoly’, from the sticker on your first bike. The highest-performing steel alloys these days include even more elements, such as nickel, niobium, titanium and copper.

The aim of the game in the development of newer steel materials is to increase strength, allowing bike manufacturers to use thinner tubing and therefore reduce the weight of the bike.

How are steel bikes constructed?

The frames of production steel bikes tend to be TIG welded together.  The tubes are cut and mitred so that they fit against one another and then a weld is made to join them together. (TIG stands for ‘Tungsten Inert Gas’, chemistry fans)

Higher end and custom-made frames commonly use lugs in the joining of the tubes. Lugs are joining pieces that fit around the ends of tubes, allowing two or more tubes to be joined together. The lugs are then brazed onto the tubes in order to secure them into place. Brazing involves the use of another metal (such as brass or silver), which is melted to form the join, and then cooled to secure it.

I could try to argue that the use of lugs benefits the performance of the bike. The argument goes something like this:

The brazing material melts at a temperature much lower than steel. By brazing on lugs, rather using higher temperature TIG welding to join the tubes directly, you avoid the risk that the tubing is brought close to its melting point, which causes the metal to crystalise and can result in the seperation of its alloys. Hence, lugged joints are stronger (all else being equal).

I could argue that.

But the truth is, steel bike aficionados tend to like lugs for aesthetic reasons. They hide what would otherwise be ‘unsightly’ welds (although there are those that will write poetry about a well-formed visible join) and introduce style and individuality into what can otherwise appear a rather utiliterian object. The use of lugs, and their design, speaks to the framebuilder’s skill – they remind the owner of the bike, and anyone that sees it, that craftsmanship went into its manufacture.

And who doesn’t like to see a little bit of craftsmanship?

Who makes steel tubing for bikes?

The major manufacturers of steel tubing for bikes are Reynolds and Columbus.

Reynolds is based in the UK (who said we’ve lost our industrial base!). The company started life in 1841 as a maker of nails, before turning to bicycle tubing at the end of the nineteenth century. The firm patented the invention of butted tubes (whereby tube walls were made thicker, and therefore stronger, at the ends) in 1898. Their flagship product these days is Reynolds 953, which purports to benefit from being a ‘martensitic-aging stainless steel alloy’ with ‘tensile strength in excess of 2000 MPa’.

I’m guessing that means that it is strong and light.

Columbus has its origins as part of an Italian firm founded in 1919 by Antonio Luigi Columbo. In addition to making tubes for bicycle framebuilders (Edoardo Bianchi was an early customer), A.L. Columbo supplied a diverse customer base, from furniture makers to manufacturers of aircraft. In 1977, a dedicated firm, Columbus, was established to develop and manufacture specialist bike tubing. Being an Italian firm, Columbus has benefited from (and contributed to) the reputation for quality associated with Italian framebuilders.

It’s always difficult to decipher the website of an Italian manufacturer (it is – I used to come across them a lot in my previous career), even when they’ve been translated into English (or maybe because they’ve been translated into English). As far as I can work out, Columbus’s top of the range steel offering is called Niobium, but your guess is as good as mine as to how it is made or why it works…

Why do people choose steel for bicycle frames?

The main argument in favour of a steel-framed bike, particularly over a carbon fibre frame, is strength and durability.

Steel is resilient to the repeated stresses placed on the bike frame when riding (flex, for instance). It is tough, being resistant to cracks and impact. When dents or nicks do occur, with steel, they are less likely to turn into full-blown failures. If there is a failure, it tends to progress slowly rather than catastrophically (unlike carbon fibre).

A steel frame can be repairable. If a tube is broken or corroded, more often than not it can be repaired or swapped out and replaced with a new one.

If you’re planning on cycling around the world (what, you mean you’re not?), and hit an argali somewhere on the Mongolian steppe, you’re more likely to find a workshop in an Ulan Bator backstreet that has the tools to fix a steel-framed bike than a carbon one.

(An argali is the world’s largest wild sheep).

Using steel is probably the most cost-effective way to get a custom-fit bike made to suit your precise requirements and body shape.

Many people (and I include myself within that number) consider steel-framed bikes to be more attractive than those made from other materials (particularly carbon fibre). This is, of course, entirely subjective. The aesthetics will depend on the design of the bike, and who (or which factory production line) made it. There are countless steel-made atrocities; some carbon fibre bikes are attractive (yes, really).

On the whole, when buying a product, people like to know there was a human directly involved in its manufacture. They like to feel there is expertise, craftsmanship and care deeply imbued within its fabric.

In buying a higher-quality, or custom-made, steel frame bike, a cyclist is supporting and celebrating the craft of bicycle-making and doing their own little bit to ensure that it continues into the future.

What are the limitations of steel as a frame material?

The traditional argument against the use of steel in high-performance bicycles is weight. All else being equal (in terms of quality and purpose), a carbon frame will be lighter than an equivalent steel one.

However, we’re not all pro riders looking to save every last gram.

Add on the weight of components (which will be the same in each case), graciously accept that we do not have the hungry whippet physique of Bradley Wiggins and then acknowledge that we would ideally like the frame to survive more than one season on our pot-holed roads, and suddenly the weight differential of the frame material becomes a little less important.

Sign up to the Grimpeur Heureux e-mail list: it’s a steel…

So that concludes my appraisal of the use of steel as a bike-making material. I hope you find it interesting and enjoyable.

The Grimpeur Heureux (that would be me) has been considering purchasing a new road bike. I’ve been looking at a variety of options, including a custom steel framed bike, to be made by a local framebuilder. If you’d like to read more about that, you can find the post here.

Look out for the other posts in this series, as I look at carbon fibre, aluminium, titanium and more unusual materials (at least as far as framebuilding is concerned).

If you liked this post, it would mean a lot to me if you could share it on the social network of your choice. Just click on one of the buttons below.

In the meantime, I wish you happy and safe riding.

Andrew

Which Bike GPS Device: The Ultimate Buyers Guide


In this post I will describe what a bike GPS device is and what it can do for cyclists. I’ll talk about the difference between a dedicated device and using the GPS functionality of your phone.

Finally, I’ll share with you a table that I have compiled, which compares the various characteristics (functions, size, weight, battery life etc) of the bike GPS devices currently on the market.

The purpose of the table was to help me choose which GPS device to buy. It certainly helped clarify my own thoughts (I went for a Garmin Edge 510). If you’re looking to purchase your first bike computer, or looking to upgrade, I do hope it will be useful to you as well.

Read moreWhich Bike GPS Device: The Ultimate Buyers Guide

What road bike should I buy: the Grimpeur considers the options

Which road bike
My bike (in a compromising position)

I have a very warm regard for my bike. As a Yorkshireman, that’s about as close a declaration of undying love you’re going to get. But it’s time to consider an upgrade (it’s always time to consider an upgrade!). My bike has been with me for more than 8 years, since I snap-purchased it whilst my then-girlfriend (now wife) sought a heavy hybrid on which to commute (she still has it, but does not seem to have developed an emotional attachment).

Despite not knowing a thing about bikes (beyond what i had learnt as the proud owner of a Raleigh Mini Burner in the 1980s – red and black, since you ask), I made a wise lucky choice.

There goes my first love

It turned out that my unassuming Dawes Giro 400, with its mishmash of Miche and Campagnolo components, would be a sturdy workhorse, carrying me safely (and sometimes quickly) across London’s potholed and white-van-stained streets. The wheels have had to be be trued countless times. The carbon front fork was replaced after an altercation with a bonnet on the Kilburn High Road. A misguided attempt to replace the rear cassette (which turned out to be a strange Campy/Shimano lovechild) has resulted in the Giro now possessing a proud set of new Campagnolo wheels.

We’ve ridden sportives together. We’ve completed London-to-Brighton. We’ve even done a couple of triathlons (he whispers). It has been a trooper.

You’re more than a number in my little red book

But times change. I am looking for a new amor (and a new bike). At this point I planned to list the reasons why I needed a new road bike. Given that I’m an adherent to the bike ownership formula (B = n +1, where B = bikes required and n = current number of bikes owned), you would think I’d simply rattle them off. But the fact is, I don’t NEED a new bike (sharp intake of breath from cyclists everywhere).

However, being now based in Derbyshire, with the Peak District starting just a couple of kilometers north from where I sit, the image in my mind’s eye of powering up (ha!) the region’s many sharp climbs does not feature the gallant Dawes.

It’s not her/him/it/you, it’s me.

I plan to keep my trusty Dawes. It will continue to do its duty as a winter bike. So my new mistress bike will be my summer and events bike.

Which road bike to buy?

I believe my requirements (which I reserve the right to change, volte-face, disregard as and when the mood takes me) are as follows:

Looks cool

Canyon road bike Rodriguez
The ‘ladies bike’….

Yes, I know, I should be primarily focused on finding the bike that serves my particular needs. But since we have established that I don’t need a new bike at all, one of my particular needs is to satisfy my vanity (and, as we’re on the topic of deadly sins, avarice). But ‘looking cool’ isn’t just visual. Being able to do the job, in my mind, contributes to looking cool.

History and race credibility are also a part of my definition (though why I’m allowing myself to define cool I do not know). For some reason, I deem Canyon (probably due to the association with Purito) and Willier (probably not due to the association with Lampre) to be cool. This might be deemed heresy, but Pinarello don’t do it for me at all.

Steel or carbon

Steel framed bike
Steel looks good – I would probably get one with a few more gears

And possibly in that order. I refer the right honourable member to my earlier comments re: looking cool. A clean, thin-tubed steel frame can just look the business.

Whilst one of the attractions of steel is that you can claim some (moral?) superiority over the carbon brigade, I am not totally against going for a carbon frame. I’m sure I’ll appreciate the reduction in weight and some of the frame designs do look nice.

I would include titanium in the list of potential frame materials but when we move onto budget, it’ll be obvious that doing so would simply not be realistic.

Comfort and performance

The fact is, I’m unlikely ever to enter a formal bike race. For most events in which I participate, the priority will be getting to the finish. I want the bike to feel (and look) fast but the most important factor will be comfort.

Budget

I have not discussed this with my wife. In fact, until I sat down to write this post, I did not know I was in the market for a new bike.

I think we’re talking £1,500 – £2,000. As the owner of a £500 bike for so long, that’s the range that I’ve always thought I would step up to.

How about a curve ball?

As I admitted above, this is the first time in a while that I’ve thought in detail about getting a new bike. In part it was prompted by seeing an attractive Ritchey steel-framed bike in a recent Cycling Weekly. But then I read the comments below the linked article, talking about Mercian Cycles and Brian Rourke frames.

Thunder crack. Thor descends from thick clouds to strike me with his custom steel hammer.

I live almost equidistant between Mercian in Derby and Rourke in Stoke-on-Trent.

Given all that I have written above (steel, credibility, history, comfort), surely I should at least investigate the possibility of having a custom steel bike. Surely I should be supporting British craftsmanship and buying local.

Surely… (echo, tumbleweed, the crushing silence of my wife’s displeasure).

Help me get my feet back on the ground

So dear readers (reader?), I seek your guidance. Can you recommend the perfect new road bike for me?

Or maybe you want to encourage me to pursue the custom route?

Does anyone have a feel for how much a fully-built custom steel frame road bike will cost? Will my stated budget just mean that I’ll have to make too many compromises on the component front?

Any and all advice gratefully received.

As always, if you like it, please retweet and share this post.

Safe cycling!

Andrew

Best cycle app: Strava or MapMyRide?

I like to look at maps. I like to plan routes. I am quite obsessed with knowing where I have been.

Not all who wander are lost – JRR Tolkien

When I first moved to London, I used to walk excessive distances on a weekend, taking delight in piecing together seemingly disjointed sections of the tube map, beginning to understand how it all fitted together.

I also like data (to a degree – nothing against stats nerds, but I’m not one).

One of my first purchases after getting my road bike (to commute on, primarily), after the obligatory lights, locks and helmet, was a cycle computer. I wanted to know how far I’d been and how fast I’d travelled (or not, as the case may be).

When I upgraded to my next cycle computer (a Polar CS200), I fastidiously logged in to the Polar website at the conclusion of each commute, in order to record each data point it had captured during the pothole- and profanity-strewn ride.

I never logged cadence though, since this is a mythical piece of data that no human-built machine is capable of sensing or recording. I digress.

Cycling apps on a smartphone (in my case a labouring iPhone 3GS) were made for me.

Read moreBest cycle app: Strava or MapMyRide?

Grimpeur Heureux goes to the London Bike Show

As the title suggests, this Saturday I went to the London Bike Show.

I had intended to cycle, but the ‘London Death Snow’ (translation for snow-familiar foreigners: a light dusting) put paid to that idea.

I was therefore unable to bask in the smug glow emanating from those attendees I saw dressed in full on commuting gear. I did however get to read a book in peace whilst travelling in on the train and tube – a rare treat.

So how was it?

Read moreGrimpeur Heureux goes to the London Bike Show