The bicycle covers adapt to the rim ring to finish forming the wheel assembly. In general, they are manufactured with rubber and there are several types, for all terrains. We can find smooth covers, with relief, thick or thin and even for different climatic conditions.
There are some covers that have been designed specifically for the triathlon mode. These are made with Graphene, an innovative material stronger than steel but, at the same time, much lighter.
Popular Triathlon Bicycle Tyres brands: