CB flywheels are precision ground to insure quick, smooth clutch action. All flywheels are drilled for 8 dowel pins. You can increase the life of your engine by cutting down on rotating weight. Lightweight flywheels are recommended for use with all stroker cranks. For street or competition use. NOTE: This picture is of a chromoly lightweight flywheel. The only difference in the cast iron flywheel has a press on ring gear.