Schwalbe marathon plus 26 bike tyre smartguardride like a pro never before have so many cyclists lined up at the start of the worlds leading cycle races using schwalbe tubes and tyres featurespunctures are a memorythe smartguard layer made from a flexible special rubber offers particular resistance to shards of glass and flints even a thumbtack cannot penetrate this protective layerthe smartguard belt does not increase rolling resistance the marathon plus rolls as easily as a tire withou