14-18 YAMAHA YZ250F: Cycra Powerflow Radiator Shrouds (Shrouds Only) (Blue) The Cycra Powerflow Intake Shrouds are the next performance leap in technology. These intake shrouds improve the airflow to the airbox by a whooping 40%. This eliminates the throttle lag off the bottom and allows the motor to run freer. This is done by increasing the volume and using Cycra's patented venturi effect scoops that pump air into the airbox. Features: Patented By-Pass Airflow Technology.