You may be surprised to discover that rubber plays no role in the structure of your tire – that’s the job of the beads and the fabric. Instead, rubber serves to protect the fabric. It’s other job is to function as the contact point between your bike and the road, serving up just the right amount of traction to keep you upright, without slowing you down with too much rolling resistance.

Traction and durability can be enhanced by combining different types of additives with the rubber. These additives are transparent to the consumer, save one. The addition of carbon black turns naturally tan-colored rubber black. Carbon black provides durability and also traction when used as tread. You may have seen tires with grey tread, which indicates the manufacturer has used a silicon compound instead of carbon black. So which is better for tread traction, carbon black or silicon? You’ll hear different opinions depending on which manufacturer you ask. There has yet to be conclusive, independent evidence presented that shows one to be superior to the other. While the trend is toward silicon, due to the common thought that it sheds water and mud better than carbon black, while still maintaining it’s stickiness (traction), the Paris Roubaix has been won on both types in recent years.

Additives that are transparent are the ones that matter most. These formulations look to improve durability (puncture resistance), traction (gripping ability), and provide less rolling resistance. Exact formulations and specific additives (silica, polymers, carbon black, “microcarbon” black) are proprietary information and often protected by the manufacturer by copyright or patent. Generally speaking, the balancing game that manufacturers play with additives is that a softer rubber compound will grip the road more, but at the expense of durability.

One solution has been to create dual compound tires, where the sturdier, harder rubber runs right down the middle, and a softer rubber is used on the sides for extra grip when cornering. Kenda and Vittoria both use this approach. Another solution is to use a soft rubber compound, but run a hard rubber compound directly behind it for reinforcement. So the soft, grippy compound is the one in contact with the ground, with the hard rubber between it and the tire casing. Michelin uses this technique with their off-road tires, and claims they’ve been able to do it without adding any weight.

Maxxis was the first to introduce triple compounds – essentially using three different rubber compounds in their tire treads. They partnered with silica manufacturer Degussa, running a silica-reinforced hard rubber compound down the center, with two progressively softer silica-based rubber compounds on the sides. The exact placement of each type of compound was determined by studying different lean angles while cornering, with particular attention given to transition areas. Maxxis uses its “3C Triple Compound Technology” in over half its high-end road race tires.

Keep in mind that this level of technology isn’t appropriate for everyone. Unless you’re racing criteriums, where high-speed cornering is of utmost importance, or racing distances where punctures would present a big problem, or riding in inclement weather conditions where grip is critical, you don’t necessarily need to invest in dual or triple compound rubber technology. With that said, if you’re a true technology aficionado, by all means, indulge in the latest and greatest. Just remember, you get what you pay for, and in this case, you’re looking at about $100 - $150 a pair, which will need to be replaced at least once during the year.

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