Cometic, cylinder base gasket. .020" copper 3-13/16" bore

84-99 Evo B.T. with 3-13/16" big bore cylinders (NU)

Type A' gasket. 3-13/16" big bore copper gasket. Type A gasket explained: The 'Type A' gasket is the early type introduced on the 1984 Evolution Big Twin models, and can be used on all of the 84-99 Evo Big Twin models and will follow the contoures of the cylinder base perfectly. They will fit 86-22 Evo XL, but stick out at the cylinder base. Both type 'A' and type 'B' have identical inner bore diameter, oil hole and stud hole locations. Gaskets for front & rear cylinder are identical. Only difference between the 'A' & 'B' gaskets is the outside perimeter.