Are you looking for mountain bike tires that don't need air, here it comes. Examine the pictures below because it is probably what you are waiting for..
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Puncture-proof tires that incorporate a flexible internal matrix instead of air are nothing new, in and of themselves. In the past several years, we’ve seen prototypes from the likes of Michelin, Amerityre, Goodyear and Bridgestone. Colorado-based Britek Tire and Rubber has also been developing something similar, known as the Energy Return Wheel.
According to Britek founder Brian Russell, the stretching of the internal rubber layer allows elastic potential energy to be stored within the wheel. As that layer is compressed by bumps transmitted from the road, the stored energy is supposedly returned (hence the name) and converted into forward momentum. It is also said to press the tread onto the road instead of allowing it to bounce off, as is sometimes the case with pneumatic tires.
The new mountain bike version of the wheels incorporate lightweight 29-inch carbon fiber rims, and (like some of the automotive prototypes) are open on the sides. Russell is wisely considering adding thin sidewalls, to keep mud and trail debris from accumulating within them.
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