powerblock s-spec is
one of the lightest tires in the world.
The ultimate BMX racing tire, the PowerBlock is designed to efficiently transfer pedal power and other rider inputs into lateral motion. In short, you'll roll faster with less wasted energy. The S-Spec version utilizes Tioga's thinnest sidewall for maximum suppleness and weight savings. Size for size, the PowerBlock S-Spec are the lightest BMX tires in the world.