22 mm inside diameter exhaust gasket for gas scooters, typically 50cc engine size but may be compatible with some models of 125cc-150cc engines Compatible with a variety of machines, including ATVs, dirt bikes, go-karts, and gas scooters. Description 22 mm inside diameter exhaust gasket for gas scooters, typically 50cc engine size but may be compatible with some models of 125cc-150cc engines. Compatible with a variety of machines, including ATVs, dirt bikes, go-karts, and gas scooters.