Scooters and go-karts alike both will use this complete gasket set for 150cc 157QMJ GY6 long case engines This gasket set was made specifically for a long case GY6 engine, as found on scooters with 12″ and 13″ rims, and as mentioned GY6 based go-karts and dune buggiesDescription Scooters and go-karts alike both will use this complete gasket set for 150cc 157QMJ GY6 long case engines.This gasket set was made specifically for a long case GY6 engine, as found on scooters with 12″ and 13″ rims, and as mentioned GY6 based go-karts and dune buggies. Several parts will not work on scooters designed to use the short case engine or 10″ wheels.If you are unsure whether your 150 GY6 is a long or a short case, just look at the clutch cover gasket. That will be the longest and largest gasket in the set. A short case clutch cover uses eight bolt holes; the long case (as shown above) will have ten.