To follow up on an earlier post, I'd like to elaborate on the various types of puncture protection, and how that relates to tire performance.

Nearly all Schwalbe tires have some type of puncture protection, and not all are created equal.

The current model of the Marathon Supreme has what is known as HD ceramic guard. It works on two principles. The HD part refers to a very densely woven Vectran belt, which is highly resistant to punctures. This belt is then vulcanized into a rubberized coating that has little shards of ceramic that are embedded into the material. The ceramic is supposed to blunt small shards of glass that can "migrate" through a tire over time. I'm not entirely sure what happened in UberIM's case unless the glass shard was fairly substantial, or he happened upon an older (2008) Marathon Supreme without the Ceramic Guard. Could be that UberIM was just unlucky.... it happens. The belt primarily covers the center contact patch of the tire, so it's possible that the piece of glass that Uber picked up was on the cornering shoulder of the tire. The premise behind this system is that it provides an exceptional amount of puncture protection without adding a lot of weight to the tire.




All that said, there is still no substitute for mass. The Marathon Plus tires have what we call "Smart Guard". Smart Guard is a 5mm thick band of "India Rubber". It has some properties that repel penetrating objects, but the primary principle at play here is that most road debris will not pentrate 8-10mm of rubber and puncture protection belt. The biggest downside is the weight.