Lightweight nylon casing nylon is a robust and durable artificial fibre used by most manufacturers for utility tyre casings traditionally it lacked the flexibility of the polycotton casings preferred by 233lite riders but was lighter in weight than polycotton threads now vittoria has succeeded in engineering nylon yarn into their exclusive nylon plus 220 and 150 tpi weave setting a new standard in each class of clincher tyres weight is cut by 10 over the previous best nylon casings whi