Login/Registered Search
Home / blog / How do rubber compounds make a tire grip? – VeloNews.com
Return to [Mobile]

How do rubber compounds make a tire grip? – VeloNews.com

Views:704 Classification:blog

How do rubber compounds make a tire grip? – VeloNews.com

“], “filter”: { “nextExceptions”: “img, blockquote, div”, “nextContainsExceptions”: “img, blockquote”} }”>

What made stage 1 of the 2020 Tour de France so slippery? Some reviews pin the blame on a publicity caravan car spraying cleaning soap bubbles on the course; others say it was merely the rain, which was the primary main storm Good had seen in fairly some time. Both of these, coupled with highway paint (assume crosswalks) had the potential to make for ice-rink-slick circumstances for riders. In such circumstances, riders depend on the tire rubber compounds to maintain them upright, however even the very best tires can’t meet all circumstances. So how do tire corporations strategy all these variables to create a tire that riders can depend on?

It’s all concerning the compound.


“Grip is outlined by a mechanical half and a chemical half,” says Samuele Bressan, head of product advertising for the bicycle division of Pirelli Tires. “The mechanical grip is coming from the aptitude of the tire (rubber + textile of the casing) to evolve over the touching floor (the footprint) at a given frequency (the upper the pace, the upper the working frequency at macro stage); the chemical grip is coming from the abrasion functionality of the rubber itself with that floor for the only real time of the contact (the upper the load, the upper the working frequency at polymers stage _micro stage).”

Received all that? Let’s break it down.

Mechanical vs Chemical

As Bressan says, two distinct aspects of the rubber are chargeable for grip: the mechanical, and the chemical. The mechanical half means how effectively the tire adheres to the highway based mostly on its footprint. In different phrases, hysteresis (the lag between an influence and the tire’s form change in consequence) elements in right here. The higher a tire can conform round an influence, the higher its mechanical grip shall be. However that’s not the one issue.

“Simplifying it so much,” says Bressan, “air inflation stress, casing flexibility, rubber static flexibility, and the power of the rider to load and push the tire onto the bottom in relation to the asphalt circumstances, are all parameters that closely affect the mechanical grip.”

The opposite half is the chemical make-up of the tire. When a rubber compound is devised, there are a number of parameters that have to be met, not simply grip. Meaning there’s a steadiness between a tire’s grip capabilities (the abrasion functionality Bressan mentions) and different elements like rolling resistance and sturdiness.

Bressan says that “pure chemical know-how of formulation and desired rubber performances at given climate circumstances, in addition to the aptitude to fabricate such a polymer mix right into a type of a bicycle tire tread, is as an alternative the half which is completely as a result of experience of the tire maker, and proving the chemical grip.”

What occurred throughout Stage 1?

To place it merely, a very loopy X-factor occurred. When rubber compounds are developed, engineers merely can’t compute for each issue that may affect a tire’s grip. That’s an not possible process. It could be essential to guage a selected oil or different issue and the way it impacts a rubber compound, then make an adjustment to accommodate. From there, you’d have to do the identical factor for each sort of chemical a rider might encounter on the highway.

Whether or not it was cleaning soap on the highway, motor oil, or simply rain-slicked highway paint, each rider’s tires throughout stage 1 encountered a situation that the mechanical and chemical grip might solely counter up till a sure level. What is probably shocking is that riders met these circumstances so ceaselessly all through the stage, pointing to some type of situation not usually encountered throughout a race (therefore the cleaning soap speculation).

Even variables riders face every single day can’t at all times be factored in. “Totally different tarmac surfaces already differ a lot in abrasion coefficient (which we usually observe and measure as a lot as we are able to, from F1 circuits right down to open roads for Rally Racing — and biking is benefiting from that too) are within the vary of a whole bunch,” says Bressan.

So Pirelli engineers hone a tire’s objective and vary of capabilities.

“We apply sure guidelines when our compounders develop rubber formulations, that are the outcomes of actually 100 years of expertise in actual world utilization,” says Bressan. “For instance, there are proportions amongst some chemical parts and components that you want to keep away from (or protect) if you’d like the crosslinks of the polymers to maintain sudden tire temperature adjustments (like what occurs throughout a skid), or a fast change in point-pressure (akin to once you hit a tiny slippery floor inside a high-load state of affairs). They’re basic standards and guidelines…that are utilized throughout the whole Pirelli merchandise, differentiating them by the utilization of the ultimate software.”

What about tread?

Pirelli Cinturato
Picture: Dan Cavallari | VeloNews.com

Deep treads on mountain bike and gravel tires account for lots of cornering grip. Street tires are a wholly totally different beast, and we’ve even heard from sure tire producers that tread patterns on highway tires don’t actually issue into grip in any respect.

Bressan disagrees; he says that tread design can issue into the mechanical element of grip, and even assist with the tire’s skill to deform on the contact patch to extend grip. He likens a highway tire’s delicate treads to sipes in your automotive’s winter tires and even on many mountain bike tires. “They’re there to permit the rubber to deform, and to both conform to the bottom roughness higher, or enhance the working temperature whereas doing that. Deformation equals a rise in temperature.”

So maybe tread does certainly issue right into a tire’s skill to grip in corners, however that’s a lot additional down the listing of essential parts of a tire’s design, and it clearly didn’t save riders from sliding out throughout stage 1 of the Tour de France.

In layman’s phrases

It positive was slippery on the market.

The most effective rubber compounds on the earth can solely counter so many variables. No matter was inflicting the roads to be as slick as they have been throughout stage 1 actually exists exterior of the X-factors most producers account for of their rubber compounds.


您好!Please sign in

Click Cancel Reply


    frebike.com providing customers with the best electric bicycle, electric mountain bikes, electric fat bike, folding electric bicycle, electric city bicycle, and hot ebike parts,etc. We have a professional R&D team that we can customize electric bikes for you, and we provide VIP DIY service. Our best selling models are in stock and can be shipped quickly.


    Phone: +86 18928076376
    Whatsapp: +86 18928076376
    Skype: +86 18928076376
    Email: service@frebike.com
    Factory Address:No.1,Xingrong Road,Sanzao Town,Jinwan District,Zhuhai City,Guangdong,China.


    AccountAccount Classification Cart May Like足记





    May Like