From frames and cranks to wheels and handlebars, two materials dominate the cycling market –carbon fibre and aluminium. Both come with pros and cons, and offer something different for every rider, which we will discuss in detail.

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Aluminium is cheaper

Aluminium as a raw material is simply cheaper than carbon sheets and resin, but that’s only a small part of the story. Manufacturing alloy components is simpler to the point where it can be automated, which lowers the cost of manufacture.

2024 canyon spectral al link2.jpg, by Liam Mercer

For carbon fibre, it’s a different story as the raw materials are pricier, but the process of creating a carbon component is more labour-intensive as layers of carbon sheets and resin are laid into expensive moulds that are specific to that component. 

2025 carbon wasp layup 2.jpg, by Liam Mercer

The lower price of aluminium components and frames makes them more appealing to those who are on a budget. On the other hand, higher-end bikes are built from carbon fibre, but, like alloy, carbon comes in different grades, so the more money you spend, the lighter and stronger that carbon becomes.

Carbon fibre is lighter and can be stronger

Despite all of the videos online of carbon handlebars snapping, carbon fibre can both be stronger and lighter than its all-metal counterparts. At the very start, the material itself is lighter and, because of that, areas of a bike can be reinforced with more carbon layers to be made stronger and still achieve a lighter weight than an aluminium frame.

2024 canyon spectral onfly riding.jpg, by Liam Mercer

Each material fails in distinct ways, however. Carbon will crack or snap suddenly, whereas alloy components will likely dent or show signs of fatigue before failure. A great example of this is in wheel rims. A carbon rim will crack under a serious enough impact, which will write off that rim. An alloy rim will dent or bend, which can both hold a seal and be repaired.

Both materials require specific torque values of whatever’s being bolted to it, so save yourself from self-led component failure by investing in a torque wrench.

Designers of carbon components have a greater ability to tune stiffness and compliance

Thanks to its lighter weight, the carbon fibre manufacturing process and the material’s ability to create more complex shapes, designers can fine-tune the balance between compliance and stiffness of a component. Although this can be done to a point with an alloy frame through butting and hydroforming, carbon fibre presents a greater opportunity for experimentation by taking away or adding layers of material.

2025 oneUp Components V2 Carbon Handlebar riding2.jpg, by Liam Mercer

With this in mind, designers can build components that focus on compliance using carbon fibre as it can be formed into vibration-reducing shapes with layups that won’t fold under pressure. This is often found in mountain bikes too, where seat stays and top tubes are built with less material to encourage vibration damping, whereas downtubes, bottom bracket shells and chainstays are built with stiffness in mind for efficient power transfer.

Again, this can be achieved with aluminium, but the parameters aren’t quite so broad without running into increased weight or lesser strength.

What about the environmental impact?

Unfortunately, carbon fibre frames aren’t as kind to the environment as aluminium. Carbon requires the use of resin, which is derived from oil, and its manufacturing process is fairly energy-intensive as it requires high temperatures. Carbon fibre isn’t easy to recycle. It can be broken down and rebuilt into smaller products that aren’t so reliant on high strength, so it can be reused, but it can't be used more than twice

On the other hand, aluminium is very recyclable. It can be recycled more than once, and doesn’t degrade during the recycling process.

Which material is best?

There’s no set answer for which is the best, as the properties of each vary so much. If you’re focused on saving as much weight as you can, that’s only possible with carbon fibre or titanium. You will need deep pockets, though. If you’re looking to have fun on a budget, you’ll be looking at alloy constructions.

Where alloy frames can be a little less forgiving regarding stiffness, if you are on a budget, you can employ carbon fibre componentry in key areas to reduce harshness. The current crop of compliance-focused carbon handlebars from the likes of Race Face and OneUp Components is a great place to start, and they’ll stave off fatigue by damping vibrations.

As with everything in cycling, it’s a case of doing plenty of research and learning what you want and attempting to invest in the right places.

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