The cycling world loves to see itself as clean, green and environmentally friendly but we know that tyres of all kinds are a source of pollution on the planet, so we contacted some of the major cycling tyre brands to find out how they're reducing the impact of their products.
We spoke to Vredestein, Continental, Specialized, Bontrager and Schwalbe about the materials they use, manufacturing processes and how suppliers are supported in the tyre production process. There are also steps we can all take to minimise the environmental impact of our tyre usage, which you can jump to by clicking here…
Although natural rubber from rubber trees is a renewable resource, demand is outstripping supply and rubber trees only grow roughly between 30° north and 30° south of the equator in Asia, Africa and South America. This is often a long way from the factories where the tyres are produced so it's not the most environmentally friendly way of doing things.
Vredestein has looked at replacing the natural rubber in its tyres with a new natural source that can be grown more easily and quickly, as well as locally in Europe to reduce CO2 emissions.
Alexander Mai of Vredestein explains: “Rubber trees only grow in tropical areas and so the extracted natural rubber has to be transported a long way to the tyre production plants.
“It also takes around 30 years for a rubber tree to be fully grown and meet its yielding potential—this is also why many rubber farmers are moving to palm tree farming with its higher yields.”
Vredestein has been working with Wageningen University and Research (WUR) to develop a locally produced natural rubber, which is extracted from the roots of Russian dandelion, called Taraxacum.
While a rubber tree takes around seven years to start supplying rubber suitable for manufacturing, the Russian dandelion produces latex just six months from being planted.
“This crossbreed dandelion plant grows smaller and has more roots than the dandelion plant we all know and see everywhere. In these roots there’s more latex," says Mai.
“Russian dandelion can be grown everywhere since it is very tough. It can also be grown in greenhouses on more storeys than just one plane.
“The plant is harvested five times a year, but the overall production is still at around 20,000 tonnes as it is just getting started.”
Vredestein has used this dandelion rubber, extracted from plants grown and harvested in the Netherlands, in its Fortezza line of high-performance road tyres. What to name this sustainable tyre? Flower Power, of course, and the power part of the name isn’t even too much of a stretch…
“Besides being good for the environment, the dandelion rubber also brings a little advantage to the usability and performance of the tyre,” Mai notes.
“With the higher concentration of natural resin, it has 2% less rolling resistance, while also providing 2% more grip.”
But Vredestein has only been able to make 250 limited edition tyres (125 pairs), and even in these small quantities, there was only enough of the special dandelion rubber material to be included in the shoulder compound.
“The long term plan is to increase the farming of these plants, but currently there is a really short supply,” Mai says. “We are on a list to receive more of the raw material when it becomes available.”
Continental has also been using rubber from Russian dandelions but from a different collaboration with the Fraunhofer Institute for Molecular Biology and Applied Ecology (IME).
The brand launched its first tyre made from this natural rubber with its all-rounder Urban Taraxagum tyre back in May 2019.
Sarah Hohmann-Spohr of Continental says: “The dandelion rubber is produced in Anklam, which is just 600km from our Korbach [Germany] factory.
“This local raw material extraction project was all about improving sustainability by getting the material closer to where it is needed, to reduce transportation emissions.
“What’s even better is that it does not stand back in terms of performance and grip compared to usually sourced natural rubber.”
Like Vredestein, Continental admits that the current output of dandelion rubber is not enough and so this has stalled the process of adding the locally extracted material to other tyres in its range.
“At Continental, we want to add value through innovation, and this is a long term project into more sustainable sourcing,” Hohmann-Spohr of Continental added.
But not all tyre brands are convinced by the feasibility of using dandelion rubber at this time.
Wolf VormWalde of Specialized says: “At this point, it is more of a story than there being industrial application for it. You would need a huge space to grow the dandelion to replace the amounts needed in the tyre industry.”
Natural rubber, from either rubber trees or dandelions, is not the only type of rubber used in bicycle tyre manufacturing. Synthetic rubber, which is a derivative of crude oil, is also used but it is not a renewable resource.
While there are some pushes for replacing synthetic rubber with natural rubbers some of the qualities of synthetic rubber cannot be replicated, VormWalde of Specialized admits.
“I can’t say that natural rubber is always a proper replacement for synthetic rubbers—it depends on the application.
“The synthetic rubbers simply give the tyre the performance riders ask for.”
Synthetic rubber is more reliable in terms of quality and can be tailored for specific performance needs.
On the other hand, VormWalde says: “Natural rubber is very abrasion resistant and slow wearing.”
VormWalde explains that Specialized does use some amounts of natural rubber in the brand’s high-performance road tyres for these qualities and he adds: “The high grades of natural rubber also have a very high density, which is great for low rolling resistance.”
While finding more sustainable sources of raw materials is one way for brands to reduce their environmental impact, another is reusing materials.
Schwalbe’s Sustainability Manager Sebastian Bogdahn explains the process that led to it using recycled materials in its products.
“We teamed up with the EPEA (Environmental Protection Encouragement Agency) environmental institute in 2013 to set up a plan to address the environmental impacts of all our processes throughout our supply chain.”
“As part of this, we set up a materials screening process which rates all the materials we use and we are continuously banning all the x-rated materials—these are found to cause a danger to the environment.
“By setting up a database with all the information on the environmental impacts, this gives us a good decision base for all future sustainability actions.”
Through this system, Schwalbe has discovered that using recycled materials can also save energy as well as reducing the cultivation of raw resources, which can be found in the brand's full report here.
“With our in-house inner tube recycling system that we introduced in 2015, we calculated that it reduces the energy input by 80% compared to production with the virgin material,” Bogdahn says.
Schwalbe’s new inner tubes use 20% recycled materials, while two new green compounds are being added to the brand’s commuting and touring tyre options.
The brand has developed a tread rubber made from renewable rubber trees and recycled rubber materials such as rubber gloves and door seals. This Green Compound also contains no carbon black—produced by the incomplete combustion of heavy petroleum products—and is used on the brand’s urban tyre called the Road Cruiser.
Then there’s the GreenGuard layer which is a 3mm thick puncture protection belt, with one third made from recycled latex products. It has been added to Schwalbe’s Marathon touring tyre, which also features an anti-ageing sidewall that is designed to withstand the cracking that results from overloading when riding with insufficient tyre pressures.
Bogdahn of Schwalbe says: “We plan to equip more products with these new compounds. While the next step would be to add to other tyres in the Active Line range, perhaps in the future we can include it in high-end tyres too.”
Joel DeMeritt, Design Engineer at Trek Bikes, notes that Bontrager are also in the process of developing tyres with reused materials.
“We are focusing our efforts on using reclaimed rubber in our commuter and urban ranges as these are the heavy hitters both in terms of how much rubber they use and how many we sell,” DeMeritt says.
“We are not going to throw the reclaimed materials on our four classic super high-end road tyres immediately because the customers want performance above all.”
In terms of other materials used in the tyres, Mai of Vredestein says: “As a tyre manufacturer there is only so much you can do because there are some crucial ingredients that you cannot replace such as carbon black.”
That said, as well as reclaimed rubber, Trek has been working with reclaimed carbon black. This is a filler product that when added to rubber turns it from being a sticky mess to what you’d expect when you buy a tyre—it increases the stiffness and torsional strength.
DeMeritt of Trek says: “Reclaimed carbon black is actually a product that is less expensive and there’s a huge supply of it.” Studies have shown that the recycling of waste tyres by pyrolysis (heating in the absence of oxygen) can recover carbon black.
In terms of the use of other chemicals in production, Reach regulations in Europe aims to protect human health and the environment from the risks posed by these substances.
VormWalde of Specialized says: “To be REACH compliant [REACH is an EU regulation to improve the protection of human health and the environment from chemical risk] there are tough and tight regulations that roll back to our material suppliers.
“Stearic acid can be used to speed up the vulcanisation process, but we have replaced that with plant oils. Also, non-aromatic oils are now used as they are not as risky in handling.
“We are using these oils in Asia too, even though it costs more and are not mandatory over there. We think if there is a reason to have these rules here we should apply them there too.”
As well as the environmental, Schwalbe’s sustainability efforts extend to the sociological and this is why the brand has partnered with the Fair Rubber Association.
“By paying a premium for each kilogram of natural rubber, we aim to improve the living and working standards of the farmers who are at the start of the supply chain,” Bogdahn of Schwalbe says.
Meanwhile, Continental has collaborated with the German Ministry of Economic Cooperation and Development (BMZ) to make its rubber supply chain digitally traceable for the first time.
The partnership is currently focused on tracing the supply chain from the Indonesian province of West Kalimantan in Borneo to ensure greater transparency and secure the livelihood of the farmer’s working there.
The 450 farmers involved are trained in sustainable cultivation, and along with better technology they have also been trained in how to cut the trees for higher yields, as well as how to make best use of the trees for longer.
Hohmann-Spohr of Continental says: “Here we are working to improve the supply chain by making it more transparent as well as working directly with farmers so we can understand how best to support them.”
The tyre industry, and the factories themselves, are naturally quite proficient in preventing waste during the manufacturing process, VormWalde of Specialized believes, as there are economic benefits to doing so.
But to ensure optimisation, Trek has extended its efforts to support its suppliers with this. DeMeritt explains: “When the factories switch from producing one tyre to another, depending on how complicated the tyre is, usually some parts of the process somewhat mess up and there’s waste in between.
“The factories want to optimise whether they care about sustainability or not as the waste is losing them money. But as some waste is inevitable, we want to support the factories by facilitating a way for those materials still to be used and so we are working directly with vendors who will process that waste into reclaimed materials.”
VormWalde of Specialized notes that the factories it works with also have systems in place. He says: “If there’s excess compound it goes back into the process and with left over casing, you can shred it and use for puncture protection materials.”
But as well as this, VormWalde notes that it is good practice to make only what you can sell to ensure you have little or no waste at the end. He admits: “It is obvious but not easily done. Keeping the product line tight can help with this and that’s what we do at Specialized.”
Troy Jones is the Social and Environmental Responsibility Manager at Specialized and he explains how the brand works with its suppliers to address its environmental impact across the entire supply chain.
He says: “We actively audit all our tier one suppliers and many of our tier two suppliers, which tyre factories come under.
“The ethical treatment of workers is foundational to our work so the audit covers labour rights, health and safety with working conditions, as well as the environmental issues including waste management and chemical handling.
“Under our audit protocol, which was developed with other bike brands as part of the Responsible Sport Initiative that launched in 2012, we ask suppliers if they have an environmental management system. Those that don’t, we work with to develop one. This improves our supply chain and also benefits lots of other brands with who we share suppliers.
“To have greater credibility with our suppliers, we are also making developments internally so we are not asking them to do something that we haven’t asked of ourselves. For example, we are building a solar installation at one of our facilities in Morgan Hill that houses our water bottle manufacturing.”
Not all sustainability drives can be seen as not all are successful. While it is great to acknowledge the significant progress that has been made in recent years, it is also worth understanding the challenges the cycling tyre brands have faced.
Schwalbe has made significant progress, but Bogdahn notes: “Introducing and working with new alternative materials is more expensive than sticking with the currently used materials.
“One of the biggest challenges we are facing is ensuring that the costs don’t explode when making a sustainable product. “
As well as the costs, the time it takes for creative sustainability ideas to be realised can also be extensive. “While our wish is to use more and more sustainable or recycled materials, it is necessary to achieve technical feasibility.
“Before the launch of a new product, there’s a very long and intensive R&D stage, to ensure the quality and safety of the products we produce.”
Alongside Schwalbe’s inner tube recycling scheme, the brand is currently in an R&D stage for a tyre recycling scheme, but Bogdahn notes: “Tubes are very easy to handle because they only contain one polymer, butyl, whereas tyres contain a mix of different chemicals, additives and compounds.
“There’s no proven technology that can handle entire bike tyres and we don’t have a proper solution at the moment.”
While it is challenging, Velorim in the UK has recently set up a scheme that can recycle tyres, alongside researching other methods to produce more useful materials. More on this later, or you can jump to this section by clicking here…
While the tyre brands can take important action in terms of the designing, sourcing of materials and the manufacturing process, there are also steps we can take as consumers to improve the lifespan of cycling tyres.
As much as it is great to do your bit to help the environment, safety is also incredibly important and so you must replace your tyres when worn. Check out our guide which goes through the warning signs you should look out for so you know when your tyres need replacing.
Too low and too high tyre pressures can both wear out your tyres prematurely.
With too little pressure you have a concave contact surface and rubbing off the sides. Mai of Vredestein explains that tyres ridden like this have cracks on the sides. “You’ll wear out your tyre carcass too fast because your contact patch changes accordingly.”
At the other end of the spectrum, Mai says: “The biggest mistake consumers make is thinking that a higher tyre pressure results in a lower rolling resistance. But when you have too much pressure you have to overcome obstacles. Absorbing obstacles is what actually reduces rolling resistance.”
As well as not maximising performance, Mai explains that when you have a high tyre pressure you have a pinpointed contact surface that wears prematurely.
Check your tyre pressure at least once a week is what Mai advises. Recommended pressure ranges are written on the side of the tyre, but these do depend on your own weight and system weight. Check out our guide to choosing the best tyre pressure here.
“If you buy cheap, you buy twice, but if you buy the high-quality product, you only have to buy once,” Wolf VormWalde of Specialized notes.
As well as choosing the high-quality product so it lasts longer, it is also important to choose a tyre that suits your riding needs. For example, taking a lightweight racing tyre on a winter ride along a route that includes narrow country lanes with unavoidable gravel sections, is going to quickly diminish the lifespan of that tyre.
VormWalde adds: “If you make a conscious choice for something that serves the specific purpose you need, then you will more likely use it to its end."
Choose high quality and one suitable for your riding needs, so you can use up the full potential of its lifespan.
Velorim is a UK recycling scheme for inner tubes and tyres, and you can find your local Velorim Centre to dispose of your used rubber here. Over 200 shops and mobile mechanics across the country are supporting the scheme by signing up as collection centres.
Richard Lawrence, the Director of Velorim, has been researching recycling methodologies since 2018 and admits the process for tyres is difficult, which goes some way to explaining why they are the only scheme out there at the moment.
He says: “Currently, we are shredding the tyres down to 15 millimetres and running a magnet over to recover the steel beads. Then the tyre goes through a second shred stage down to 5 millimetres—this material goes into products such as safety floors and kids playgrounds. Fibre is also recovered and this can be used in construction and for insulation.”
But Velorim says this is just an interim recycling process. Alongside these processes, Velorim has two research streams running parallel to reprocess the tyres into viable new raw materials.
“We are looking at the de-vulcanization of the rubber. Vulcanisation is when sulfur is injected into the rubber and it is heated. This transforms the rubber from a gel into a stiff product.
“It has always been possible to chemically break the bonds between the sulfur and the rubber to recreate the rubber. But the methods currently used, which involve injecting acids and chemicals to break the bonds, are quite toxic.
“We are working on a cryogenic system. Essentially you freeze the rubber, then grind it and heat it—this is a purely mechanical process to break these bonds.”
As well as this recycling route, Velorim is looking into pyrolysis. “This is very high-pressure temperature cooking, but not incineration. By using very high temperatures you end up with carbon black, very hard little pellets and an oil which can be used in manufacturing and, with a little refinement, as a replacement for diesel.”
“What we are probably going to end up with is not circular but spiral. We are making products that can be used in manufacturing, but not necessarily for making tyres,” Lawrence says.
While Velorim continues to research new ways to safely reprocess every component of tyres, Lawrence asserts: “Even now, we have made a commitment that no tyres will go to landfill, none will be incinerated and zero waste will be exported.” An independent environmental assessor has been appointed to report on Velorim’s compliance with this.
By taking your used tyres to one of Velorim’s collection centres the tyres can be recycled, as well as used in a research project for better future recycling processes.
Buy products from brands that are putting the effort into producing more sustainable products.
It would help brands justify devoting time and money to developing more sustainable products if there was proof of demand. It would be nice to hear that some brands do care about the environment enough to do something regardless, but let's be honest, the reality is an economic incentive can go a long way to encourage a brand to care.
Show support by engaging on the brand’s social media channels, by liking or commenting positively on a post that details sustainability progress.
Tyres are constantly degrading as the vulcanisation of the tyre does not stop after the cured compound is removed from the mould, Mai of Vredestein notes.
“When it comes out of the mould it is only about 99% ready. The last 1% is a past curing process that happens to the tyre by just sitting on a shelf. It is fully usable in this state, but then once you overcome that curing process, the tyre starts to degrade,” Mai explains.
The shelf life of a tyre is around five years according to Mai, but it does depend on the temperature at which the tyre is stored.
The lifespan of a tyre can vary, regardless of how many miles you put it through when riding.
“UV radiation can cause cracks and degrade the tyre life. You should store tyres out of the sun, and not leave your bike out in the open very often, to avoid this harmful UV,” Mai of Vredestein notes.